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              Common Spectrum Management Interface MIB     June 13,1996



                          Definitions of Managed Objects
                          for HFC RF Spectrum Management

                                  June 13,1996

                           draft-ahmed-csmimib-mib-00.txt

                                   Masuma Ahmed
                                mxa@cablelabs.com
                                 Mario P. Vecchi
                             mario.vecchi@twcable.com




          1.  Status of this Memo
          This document is an Internet-Draft. Internet-Drafts are
          working documents of the Internet Engineering Task Force
          (IETF), its areas, and its working groups. Note that other
          groups may also distribute working documents as
          Internet-Drafts.

          Internet-Drafts are draft documents valid for a maximum of
          six months and may be updated, replaced, or obsoleted by
          other documents at any time. It is inappropriate to use
          Internet-Drafts as reference material or to cite them other
          than as "work in progress."

          To learn the current status of any Internet-Draft, please
          check the "lid-abstracts.txt" listing contained in the
          Internet-Drafts Shadow Directories on ds.internic.net
          (US East Coast), nic.nordu.net (Europe), ftp.isi.edu (US
          West Coast), or munnari.oz.au (Pacific Rim).

          2. Abstract

          This document was issued by Time Warner Cable to the
          industry on December 24, 1995 as a private extension
          to the SNMPv1 MIB.  As issued by Time Warner, this
          memo defined a private portion of
          the Management Information Base (MIB) for use
          with network management protocols
          in the Internet community. It described objects used
          for managing Radio Frequency (RF) spectrum and the
          related configuration parameters allocated to
          different vendors' products in Hybrid Fiber Coax (HFC)
          networks.

          This document is submitted as it is for information
          purposes only and the authors plan to update the
          document consistent with the guidelines and structure
          of the Internet Drafts as specified in RFC 1543.
          The authors also plan to specify this MIB module
          in a manner that is both compliant to the SNMPv2
          SMI, and semantically identical to the existing
          SNMPv1-based definitions.

          This memo does not specify a standard for the Internet
          community.  It is presented for discussion purposes
          only.



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              Common Spectrum Management Interface MIB     June 13,1996



          3.  The Network Management Framework

          The Internet-standard Network Management Framework consists of
 three
          components.  They are:

              RFC 1155 which defines the SMI, the mechanisms used for
              describing and naming objects for the purpose of management.
              RFC 1212 defines a more concise description mechanism,
              which is wholly consistent with the SMI.

              RFC 1156 which defines MIB-I, the core set of managed objects
              for the Internet suite of protocols.  RFC 1213, defines
              MIB-II, an evolution of MIB-I based on implementation
              experience and new operational requirements.

              RFC 1157 which defines the SNMP, the protocol used for
              network access to managed objects.

          The Framework permits new objects to be defined for the purpose of
          experimentation and evaluation.


          4.  Conventions

          The following conventions are used in this document with the
          exception of Section 10.

          o Requirement - A feature or function that is required to be
             necessary to support the RF Spectrum Management. A
             Requirement contains the word "Shall" and is identified
             by the word "Requirement" in the left margin.

          o  Objective - A feature or function that is desirable and may
             be required to support the RF Spectrum Management.  An
             Objective contains the word "Should" and is identified by the
             word "Objective" in the left margin.



          5.  Objects

          Managed objects are accessed via a virtual information store,
          termed the Management Information Base or MIB.  Objects in the
          MIB are defined using the subset of Abstract Syntax Notation
          One (ASN.1) defined in the SMI.  In particular, each object






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          type is named by an OBJECT IDENTIFIER, an administratively
          assigned name.  The object type together with an object
          instance serves to uniquely identify a specific instantiation
          of the object.  For human convenience, we often use a textual
          string, termed the descriptor, to also refer to the object
          type.

          5.1.  Format of Definitions

          Section 10 contains the specification of all object types
          contained in this MIB module.  The object types are defined
          using the conventions defined in the SMI, as amended by the
          extension specified in RFC 1212 and RFC 1215.






































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          6.  RF Access Network Architecture Overview

          The Radio Frequency (RF) reference access network architecture
          consisting of Distribution Hub (DH) or Head End (HE), Fiber
          Node (FN), and fiber optics and coaxial distribution plants is
          shown in Figure 1.



  To other<---//----|
  DH or   ---//--->||                          ________    |<--------->
  HE               ||                          |      |    |Co-axial     500
                   ||                   |------|Fiber |----|Distribution=
 homes
             ______||______ Fiber Optics| |--->|Node  |    |<--------->
 passed
             |            |<-----//-----| |    |______|
             |Distribution|------//-------|
             |Hub (DH)    |                            |<---------->
             |or          |                 ________   |
             |Head End    |   Fiber Optics  |      |---|<-----Co-axial
 500
             |(HE)        |<-------//-------|Fiber |        Distribution
 homes
             |____________|------//-------->|Node  |---|<---------->
 passed
                   ||  Up to                |______|   |<---------->
                   || 20,000
  To other  <--//--|| homes passed          Up to 40
  DH or     --//--->|                       Fiber Nodes
  HE


       Figure 1: RF Reference Access Architecture, HFC Distribution Plant


          The backbone of a typical large metropolitan network
          interconnects the Primary HE with the DHs using multiple fiber
          optic links, in most cases completing bi-directional rings.
          This fiber optic backbone network is not of interest as far as
          the management of RF spectrum allocation is concerned.

          From each DH ( or the HE), the Hybrid Fiber Coax (HFC)
          subnetworks provide connectivity to the subscriber premises.
          This document addresses the allocation of RF spectrum in these
          HFC subnetworks.

          An HFC subnetwork consists of optical fibers from the DH to
          each Fiber Node (FN), and then a coaxial distribution plant







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          from each FN to the subscriber premises.  Two separate optical
          fibers between the DH and each of the FNs carry the downstream
          RF spectrum (typically, 50 to 550 or 750 MHz) and the upstream RF
          spectrum (typically, 5 to 40 MHz).  At the FNs, electrical to
          optical conversion occurs, and the electrical RF spectrum of
          the downstream and upstream signals are combined onto a single
          coaxial cable distribution plant.  Diplex filters and bi-
          directional RF amplifiers allow a single coaxial cable to
          carry bi-directional traffic separated in the frequency
          domain.  It is the limited RF spectrum available in the
          coaxial distribution plant that motivates spectrum management
          across the HFC subnetworks.

          The RF spectrum allocation in the coaxial distribution network
          typically places the downstream traffic in the 50-750 MHz
          region, and the upstream traffic in the 5-40 MHz region.
          Other options are possible, such as planning the return
          spectrum in the high frequency range, 900-1000 MHz, for
          instance.  The downstream traffic represents the RF signal
          going towards the subscribers premises and consists of
          multiple analog channels of NTSC entertainment video, each 6
          MHz wide, as well as digital traffic modulated over RF
          carriers.  The upstream traffic represents the return signals
          from the subscribers, digitally-modulated RF carriers for bi-
          directional services such as pay-per-view (ppv) activation,
          telephony, and high-speed data services.

          It should be noted that in many implementations the downstream
          signals from several Fiber Nodes (typically 3 to 5) are
          obtained from an optical splitter that feeds from a single
          modulated laser.  This implies that the same physical signals
          could be sent downstream to 3-5 nodes, even though in the
          upstream direction all the Fiber Nodes are independent.  It is
          important, therefore, to recognize the inherent asymmetry of
          Hybrid Fiber Coax networks, not only in the total bandwidth,
          but also in the physical aggregation of signals to (and from)
          the different Fiber Nodes.  If two or more Fiber Nodes are
          supported by a single optical transmitter (or receiver) at the
          DH (or HE) then for RF spectrum management purposes they are
          considered as one HFC subnetwork.  This is because the same
          physical signal occupying the same RF spectrum is sent to
          multiple Fiber Nodes.

          In some HFC subnetwork designs, to provide greater upstream
          frequency bandwidth, the service area of a Fiber Node is split






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          into smaller areas (e.g., a 500 home neighborhood may be split
          into four 125 home areas), each of which is served by a
          separate co-axial trunk, and hence, has independent upstream
          channel spectrum.  To support this method, known as block
          conversion, the upstream channel received over the coax trunks
          are frequency shifted (as shown in Figure 2) and combined at
          the FN before transmission back to the Distribution Hub (or
          HE).  For the purpose of RF spectrum management, each block
          convertor is considered as a separate HFC subnetwork in the
          upstream direction.



                                 Co-axial
                               Distribution
                __________                       _____
                |        |<------25 MHZ----------|BC |-<--25 MHz------    |
                |        |                       |___|                    |
                | Fiber  |                       _____                    |
                | Node   |<------50 MHz----------|BC |-<--25 MHz------   500
                |        |                       |___|
 homes
                |        |                       _____
 passed
                |        |<------75 MHz----------|BC |-<--25 MHz------    |
                |        |                       |___|                    |
                |        |                       _____                    |
                |________|<------100 MHz---------|BC |-<--25 MHz------    |
                                                 |___|

         BC - Block Converter


               Figure 2:  Block Conversion of Upstream Frequency Spectrum



          The goal of the spectrum management functions is to control
          the RF spectrum in both upstream and downstream directions
          allocated to different vendors' products to provide digital
          services.  The assignment of non-overlapping RF spectra in the
          HFC broadband network enables the co-existence of many
          different vendors' products supporting digital services in a
          single physical HFC subnetwork.  Different vendors' products
          may support different modulation techniques.  By managing the
          RF spectrum (and the related parameters) of each physical HFC







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          subnetwork, one can create many independent logical HFC
          subnetworks each of which supports a number of products.
          Thus, RF spectrum management allows co-existence of different
          vendor technologies in a single physical HFC subnetwork.
          Therefore, logical HFC subnetwork is conceptually a portion of
          the shared physical HFC subnetwork resources that is dedicated
          to a single vendor equipments supporting a number of products
          to provide digital services to subscribers.  Each vendor
          technology can operate independently of all other vendors'
          technologies as long as it remains within its assigned range
          of the RF spectrum and the related configuration parameters
          such as signal power levels.  The equipments to be installed
          will require the capability to stay within the spectrum (and
          the other related parameters) boundary in response to the
          request received from the spectrum management application, in
          a manner consistent with the RF spectrum management MIB
          structure described in the following sections.


          7.  RF Spectrum Management Architecture

          The network management architecture supporting RF Spectrum
          Management consists of the following components:

            - Spectrum Management Application (SMA)
            - Spectrum Management Proxy Agents (SMPAs)
            - Logical RF access networks
            - Logical HFC subnetworks


          As mentioned earlier, several logical RF access networks can
          be supported in a single physical RF access network, each
          supported by a different vendor.  Vendors' logical RF access
          networks are used for supporting different products to provide
          digital services such as digital telephony service, high speed
          data service, and interactive multi-media service in the same
          physical Hybrid Fiber Coax (HFC) subnetwork.  A logical RF
          access network will use the physical HFC subnetwork subtended
          on a given DH, including multiple FNs (typically 40) and their
          respective multiple co-axial plants.

          A logical HFC access subnetwork will use the physical HFC
          subnetwork associated with a single FN (or multiple FNs
          depending on the architecture lay-out), including the fiber
          links (from the DH to the FN), and the co-axial plant.  The






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          products supporting digital services in logical HFC
          subnetworks overlaid over a single physical HFC subnetwork
          will all share the same RF spectrum range associated with that
          physical HFC subnetwork.

          The network management architecture supporting SMA, SMPAs and
          logical RF access networks is shown in Figure 3.  Each logical
          RF access network is required to support an SMPA and the
          common spectrum management interface (csmi) to the SMA.

          o Requirement(1) - The logical RF access network provided by a
                             vendor shall support a Spectrum Management=
 Proxy
                             Agent (SMPA) and the common spectrum management
                             (csmi) interface to the Spectrum Management
                             Application (SMA).












































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                                    _____________
                                    |           |
                                    |Spectrum   |
                                    |Management |
                                    |Application|
                                    | (SMA)     |
                                    |___________|
                                      |       |
                               csmi --|--  ---|--- csmi (SNMPv1)
                             |--------|       |
              /--------------|----------/=
 /---|---------------------------------/
              /         _____|_________ / / __|____________         ________=
   /
              /         |(SMPA)       | / / |  (SMPA)     |        /Logical=
 /  /
              /Logical  |Distribution | / / |Distribution |       /HFC sub/
  /
              / RF      |Hub          | / / |Hub          |------/network/
  /
             / Access   |Equipment    | / / |Equipment    |     /_3_____/
  /
             / Network1 |(DHE)        | / / |(DHE)        |
  /
             /          |_____________| / / |_____________|
 /
             /            |       |     / /    |         |        Logical
 /
             /        ____|       |     / /    |         |           RF
  /
             /      __|_____   ___|____ / /   _|______   |----|     Access
  /
             /     /Logical / /Logical/ / /  /Logical/     ___|____ Network2=
  /
            /     /HFC sub / /HFC sub/  / / /HFC sub/     /Logical/
  /
            /    /network / /network/   / //network/     /HFC sub/
  /
            /   /_1______/ /__2____/    / /__1____/     /network/
 /
           /--------------------------- / /            /_2_____/
 /

 /----------------------------------/


          csmi - common spectrum management interface
          HFC - Hybrid Fiber Coax
          SMPA - Spectrum Management Proxy Agent


                  Figure 3: RF Spectrum Management Reference Architecture
















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          As shown in Figure 3, the vendor's logical RF access network
          consists of a Distribution Hub Equipment (DHE) and multiple
          logical HFC subnetworks.  As shown, the vendor's DHE will
          support more than one logical HFC subnetworks in a star
          configuration.  Also, the logical HFC subnetworks such as HFC
          subnetworks 1 and 2 may be supported over a common physical
          plant even though these two logical HFC subnetworks may be
          provided and managed independently by two different vendors'
          network equipments.

          An example physical RF access network supporting three logical
          RF access networks (DHE 1, DHE 2, and DHE 3), each provided by
          a different vendor is shown in Figure 4.  In this simplified
          example, there is only one physical HFC subnetwork subtended
          by the DH, and hence there are three logical HFC subnetworks
          which share the RF spectrum range across the same physical HFC
          subnetwork.


































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              Common Spectrum Management Interface MIB     June 13,1996






     Distribution Hub (DH)
   --------------------------
   | ________               |
   | |DHE 1 |450MHz         |
   | |______|--------->|    |
   |                   |    |
   | ________       ___|____RF Combiner
   | |DHE 2 |500MHz |  |-> ||
   | |______|-----> |----->|---->
   |                |  |-->||   |
   | ________       |__|___||   |
   | |DHE 3 |550MHz    |    |   |
   | |______|--------->|    |   |        /-----------------------=
 --------------/
   |                        |   |        /
    /
   |                      ______|________/_ Forward Spectrum______
 /-----/  /
   |                      |  HF/Optical Tx|____//________>=
 /Fiber/----/Co-axial//
   |                      |_______________|               /Node /-----/Plant=
  //
   |                      |  LF/Optical Rx|<______//_____/_____/----- /
 / /
   |                      |_______________|
 /------/  /
   |                            |       /  Reverse Spectrum
    /
   | ________               |   |
 /--------------------------------------/
   | |DHE 1 |20MHz          |   |                Physical HFC Subnetwork
   | |______|<---------|    |   |
   |               ____|___ |   |
   |               |   |  | |   |
   | _______ 25MHz |   |<-| |   |
   | |DHE 2|<------|<-----|-<---|
   | |_____|       |   |<-| |
   |               |___|__|RF Splitter
   | ________          |    |
   | |DHE 3 |30MHz     |    |
   | |______|<---------|    |
   |------------------------|

   DHE - Distribution Hub Equipment               ------------ Electrical
   HF - High Pass Filter                          ____________ Optical
   LF - Low Pass Filter
   Optical Tx - Optical Transmitter
   Optical Rx - Optical Receiver


  Figure 4: Three Logical RF Access Networks in a Physical RF Access Network






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          7.1.  Spectrum Management Application (SMA)

          The SMA co-ordinates and manages the RF spectrum (and the
          related configuration parameters) across several different
          logical HFC access subnetworks overlaid over a single physical
          HFC access subnetwork.

          o Requirement(2) - The Spectrum Management Application (SMA)
                             shall co-ordinate and manage the RF spectrum
                             and the related configuration parameters
                             across several different logical HFC
                             subnetworks provided by different vendors'
                             equipments and supported over a single physical
                             HFC access subnetwork.

          Each logical RF access network that belongs to a specific
          vendor's network equipments may support more than one products
          to provide digital services such as digital telephony service,
          high speed data service, and digital video service.  It is
          also possible that more than one logical RF access network in
          the same physical RF access network will support products to
          provide the same digital service such as digital telephony
          service.  All products that are supported by the logical HFC
          subnetworks share the RF spectrum (and the related
          configuration parameters) associated with the underlying
          physical HFC subnetwork.

          As mentioned, the SMA allocates and manages via a common
          spectrum management interface (csmi), the RF spectrum (and the
          related configuration parameters) to different vendors'
          products that are used to support digital services such as
          high speed data service, digital telephony service,
          Asynchronous Transfer Mode (ATM) service, and interactive
          multimedia service in the same physical HFC access subnetwork.
          In the context of RF spectrum management, products supporting
          services are primarily distinguished by the underlying
          technology used.  For example, products supporting POTS and
          products supporting ATM service are distinguished by the
          transport technology used even though both POTS and the ATM
          products may both support voice service.

          csmi provides an SNMPv1 interface between the SMA and SMPA.

          o Requirement(3) - The common spectrum management interface (csmi)
                             shall support an SNMPv1 interface between the






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                             Spectrum Management Application (SMA) and the
                             Spectrum Management Proxy Agent (SMPA) to=
 manage
                             the RF spectrum and the related parameters
                             of the HFC access subnetworks.


          o Requirement(4) - The SMPA shall support an RF spectrum=
 management
                             MIB containing objects on vendor's different
                             product classes that shall be supported in the
                             logical HFC subnetworks in order for the SMA
                             to manage the RF spectrum and the related
                             configuration parameters of the logical
                             HFC subnetworks.


          o Objective(1) - The common spectrum management interface (csmi)
                           between the SMA and SMPA should be able to evolve
                           to SNMPv2 in the future.


          The SMA provides and maintains the global view of the RF
          spectrum (and the related configuration parameters) allocation
          across all logical HFC subnetworks in the same physical HFC
          subnetwork.  The SMA therefore has the ability to coordinate,
          manage and allocate RF spectrum and the related parameters
          associated with the physical HFC subnetwork to all products
          providing services that are supported using multiple logical
          HFC subnetworks in the same physical HFC subnetwork.  In
          addition, the SMA retrieves the performance and utilization
          data on each logical HFC subnetwork from the appropriate
          performance and traffic management systems. Based on the
          performance and utilization data, the SMA may allocate, de-
          allocate, or reconfigure the RF spectrum channels.

          In addition, as a backup spectrum, the SMA may allocate
          additional RF spectrum to a vendor's product supporting
          digital services in a logical HFC subnetwork.  Backup spectrum
          may be needed to accommodate service performance objectives of
          some vendor's products in a logical HFC subnetwork.  The
          backup spectrum may be used to maintain the service quality
          for situations when allocated RF channels exceed their
          capacity or degrade in performance. The SMA may also allocate
          additional spectrum on an needed basis, e.g., upon receiving a
          request from a logical HFC subnetwork.  Such requests may be
          generated by the SMPA using SNMP traps.







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          The SMA does not perform call processing, dynamic bandwidth
          management, connection management, or even protection
          switching.  These capabilities require real-time control,
          management and allocation of network resources and are
          therefore supported using call processing or dynamic bandwidth
          management entities in the vendor's network equipments.

          As mentioned in Section 6, a single optical transmitter or
          receiver at the DH (or HE) could be used to support multiple
          Fiber Nodes and thus multiple HFC subnetworks.  For RF
          spectrum management purposes, the physical HFC subnetworks
          supported by a single optical transmitter (or receiver) at the
          DH (or HE) is considered as one physical HFC subnetwork (and
          thus one logical HFC subnetwork) in the downstream (or
          upstream) direction.  Similarly, for an HFC subnetwork
          supporting block conversion, each block convertor is
          considered as a separate HFC subnetwork.  It is assumed that
          the appropriate configuration management system will contain
          detailed information on the network lay-out including the
          number of HFC subnetworks supported per optical transmitter or
          receiver at the DH (or HE). To allocate and manage RF spectrum
          efficiently, the SMA will retrieve the HFC physical network
          configuration information for both upstream and downstream
          directions from the configuration management system.

          Because of the inherent HFC asymmetry in the upstream and
          downstream directions, the upstream and downstream HFC
          subnetworks are treated as separate networks in the RF
          spectrum management MIB.  The SMA maintains the correlation
          between the upstream and downstream RF channels and their
          relationship to the specific product class.

          As mentioned, to manage and co-ordinate the RF spectrum across
          different logical HFC subnetworks, SMA communicates with the
          appropriate network management systems such as configuration
          management system, performance and traffic management system,
          and fault management system of the cable network.  Since these
          management systems belong to and operated by a single cable
          network provider, the SMA may communicate with these
          management systems using a proprietary network management
          protocol.  Wherever these management systems are not
          available, the SMA may manually obtain the required management
          data to manage RF spectrum across different logical HFC
          subnetworks.  Also to manage the RF spectrum, the SMA needs to
          retrieve information on the physical lay-out (e.g., the number
          of active amplifiers, taps, homes passed in the network,
          number of Fiber Nodes supported by a single transmitter or
          receiver at the distribution hub) and physical characteristics
          (e.g., distortion ratios, forward and return path loss ratios,


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              Common Spectrum Management Interface MIB     June 13,1996


          signal level variation, and attenuation ratios) of the HFC
          subnetworks from the appropriate management systems (see
          reference 12).

          This MIB increases the exposure of the network to unauthorized
          SNMP managers in that units could be reconfigured to use
          frequencies which impact other services. A standard solution will=

          become possible by extending to the use of SNMPv2. It is possible
          in the first deployments to provide ad-hoc standard security
          approaches.  For instance, key parameters are read only to SNMP.
          One could require a reset to change these at which time the units
          read a parameter file from a server. In any event, the interaction
          between the SMA and the SMPA will be secured physically and any
          exchanges between the SMPA and the end devices needs to be=
 secured.

          In summary, the SMA performs the following functions:

           - maintains a map of those logical HFC subnetworks
             (belonging to different logical RF access networks,
             each supported by a different vendor) that belong
             to the same physical HFC subnetwork.  For example,
             the SMA maintains the association between the logical
             HFC subnetworks (numbered as 1) in the logical
             RF access networks 1 and 2 in Figure 3 and the physical
             HFC subnetwork to which they belong.

           - co-ordinates, manages and allocates RF spectrum (and the
             related configuration parameters) of the physical HFC
             subnetwork to multiple vendors' products supporting digital
             services.  These products are supported using multiple logical
             HFC subnetworks in the same physical HFC subnetwork.
             The logical HFC=CAsubnetwork map is used by the SMA to manage
             and allocate RF spectrum of the physical HFC subnetwork to
             the products supported in the logical HFC subnetworks
             (e.g., logical HFC subnetworks numbered as 1 in logical
             RF access networks 1 and 2).

           - maintains the correlation between the upstream and downstream
             RF channels and their relationship to a specific product class.

           - communicates with network management systems such as
             configuration management system, performance and traffic
             management system, and fault management system to determine
             the configuration and performance of the physical HFC
             subnetwork and the logical HFC subnetworks in order to
             manage and co-ordinate the RF spectrum allocation.

          From the above discussion, it is clear that the SMA is the
          management entity that possesses the intelligence and the
          ability to manage RF spectrum (and the related configuration


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              Common Spectrum Management Interface MIB     June 13,1996



          parameters) of several logical HFC subnetworks that belong to
          the same physical HFC subnetwork via the csmi.

          7.2.  Spectrum Management Proxy Agent (SMPA)

          The SMPA supported by each logical RF access network acts as a
          proxy agent and supports the RF spectrum management MIB to
          manage the RF spectrum (and the related configuration
          parameters) in the SMPA's logical HFC subnetworks.  Initially,
          the management interface between the SMPA and the logical HFC
          subnetworks may be a vendor proprietary interface.  However,
          in the future, it is possible that the interface may support a
          standard management protocol such as SNMP.  Note that the SMPA
          has knowledge of the allocation of RF spectrum to the products
          providing digital services in its own logical RF access
          network only.  The SMPA does not have any information on RF
          spectrum allocated to other logical RF access networks even
          though these logical networks may also be supported in the
          same physical RF access network.

          As noted above, the SMPA has a local view of the RF spectrum
          (and the related configuration parameters) that is allocated
          to products providing services in its own logical subnetworks
          only.  In order for the SMA to manage RF spectrum (and the
          related configuration parameters) across several logical HFC
          subnetworks, the spectrum management MIB supported by each
          SMPA must provide local RF configuration information of its
          logical HFC subnetworks such as RF modulation techniques, RF
          spectrum frequency agility, and the RF power levels.


          8.  RF Spectrum Terminology

          Some basic RF spectrum terminologies are described in this
          section to facilitate defining the RF spectrum management
          managed objects.


          8.1.  Forward and Reverse RF Spectrum

          Forward RF spectrum refers to the bandwidth (in Hz) allocated
          in the network to subscriber direction for transmitting
          information from the network to the subscriber. Similarly, the
          reverse RF spectrum refers to the bandwidth (in Hz) allocated







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              Common Spectrum Management Interface MIB     June 13,1996



          in the subscriber to network direction for transmitting
          information from the subscriber to the network.  The forward
          and reverse spectrum are also referred to as downstream and
          upstream spectrum respectively.  An example forward and
          reverse RF spectrum allocation across an HFC subnetwork is
          shown in Figure 5.  Most of the existing HFC subnetworks use
          sub-split system which uses 5 to 40 MHz for the reverse RF
          spectrum.  Upgraded HFC subnetworks typically support forward
          RF spectrum in the 50 to 750 MHz range.  A transition band
          between upstream and downstream spectra is unused due to the
          roll-off behavior of the diplex filters.



                                    |forward spectrum
                                    |----------------->
                                    |
                     _____________  |______________________________
                     |           |  |                             |

 <------|-----------|--|-----------------------------|---------->
                     5           40 50                            750
                                 |  |     Frequency [MHz]
                 <---------------|  |
                 reverse spectrum|  |



         Figure 5: An Example Forward and Reverse RF Spectrum Allocation



          8.2.  RF Modulation Techniques

          Digital modulation is the process by which digital symbols are
          transformed into sinusoidal waveforms that are compatible with
          the characteristics of the RF channel.  Modulation allows the
          amplitude, frequency, or phase of an RF carrier wave (or a
          combination of them) to be varied in accordance with the
          information to be transmitted on that carrier.

          Different modulation techniques are used to achieve different
          spectral efficiency and to minimize interference effects.  The
          spectral efficiency is measured in terms of bits per second
          per Hz of transmission.  The commonly used modulation
          techniques are Quaternary Phase Shift Keying (QPSK),
          Quadrature Amplitude Modulation (QAM), Frequency Shift Keying
          (FSK), and Vestigial Side Band (VSB) modulation.  The primary





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          objective of spectrally efficient modulation technique is to
          maximize the bandwidth efficiency, i.e., to maximize the bits
          per second per Hz transmission.  Higher spectral efficiency
          can be achieved using higher order modulation techniques but
          there is a trade-off with the error performance.  For example,
          256 QAM may be used instead of 32QAM to obtain higher spectral
          efficiency (e.g., providing 6.4 bits per second per Hz
          compared to 3.2 bits per second per Hz spectral efficiency)
          with a different trade-off between bit error rate,
          transmission power and cost.  Sometimes, spectral efficiency
          is reduced (e.g., to transmit information in a hostile RF
          environment such as the reverse RF spectrum) to form a
          compromise between bit error rate, power and cost.  In those
          cases, lower order modulation technique such as QPSK
          modulation technique may be used. Also, depending on the
          reverse plant requirements, robust modulation techniques
          such as spread spectrum modulation technique may be used.

          In order to support different modulation techniques in the
          same physical HFC subnetwork, the different modulation
          techniques must use non-overlapping RF frequency spectrum with
          the exception of the non-synchronous spread spectrum modulation
          techniques such as non-synchronous Direct Sequence Spread
          Spectrum (DSSS) modulation techniques.  If non-synchronous
          spread spectrum modulation technique is used, it is important
          that the power level setting for spread spectrum
          modulation technique is low compared to the other modulation
          techniques.  Note that the synchronous spread spectrum
          technology does not have this issue associated with it.
          For detailed discussions on modulation techniques,
          see reference [11].


          8.3.  RF Channel

          Radio Frequency (RF) Channel is defined as the minimum radio
          frequency band that is used by a given modulation technique to
          support a given product class.  For example, a specific
          modulation technique may use a 6 MHz channel.  For the purpose
          of the present document, it should be noted that the
          definition of channel bandwidth includes both usable and guard
          bandwidths.  The position of an RF channel is defined as the
          center of the RF carrier frequency.  Example RF channels and
          the respective carrier frequencies are shown in Figure 6.  RF
          channels can be frequency agile or fixed.  In case of a fixed
          frequency RF channel, the position of the RF channel cannot be
          changed to another RF carrier.  On the other hand, the
          position of a frequency agile RF channel can be moved to a
          different RF carrier.  For a given modulation technique, the
          RF channel width is independent of the modulation order if the
          same symbol rate is supported for all modulation orders.






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                              | |                |   |
                              | |                |   |
                              | |                |   |
                     ---------|-|----------------|---|--------------
                              2 MHz channel      6 MHz channel
                               ^                   ^
                               |                   |
                            at 32 MHz           at 260 MHz


                     Figure 6: Example Radio Frequency Spectrum Channels


          8.4.  RF Spectrum Slice

          For the purpose of RF spectrum management, RF Spectrum Slice
          is defined as the RF spectrum interval associated with a group
          of fine-grained modulators.  An RF spectrum slice supports one
          or more RF spectrum channels of the same type allocated to a
          given product class to provide digital services (e.g.,
          multiple telephony voice channels in a POTS service).  The
          position of the RF spectrum slice is defined by two
          parameters:  upper frequency and lower frequency.  The upper
          and lower frequencies are defined as the upper and the lower
          frequency limits of the RF spectrum slice.  The RF spectrum
          slice can be frequency agile or fixed depending on the
          behavior of the RF channels that make up the RF spectrum
          slice.





















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                         (lower frequency)        (upper frequency)

                            20MHz                   30MHz
                             |  |  |  |  |  |  |  |  |
                             |  |  |  |  |  |  |  |  |
                             |  |  |  |  |  |  |  |  |
                      -------|--|--|--|--|--|--|--|--|---------
                             |      RF channels      |

                             <------10 MHz Slice----->


                   Figure 7: An Example Radio Frequency Spectrum Slice



          8.4.1.  RF Spectrum Slice Edge Characterization

          In order to efficiently stack RF spectrum slices in the same
          physical HFC subnetwork belonging to different product
          classes, the SMA needs to know the spectral roll-off
          characteristics of the typical RF spectrum slice supported by
          each product class.  Vendors may support different product
          classes using different modulation techniques and hence
          different RF channel types.  Since RF spectrum slices
          belonging to different product classes may be stacked at
          different points in the RF spectrum and may have different
          frequency widths, it is important that the spectral roll-off
          characteristics provided for a typical spectrum slice of each
          product class take into considerations of these parameters.
          Also, the slice spectral roll-off characterization should be
          closely related to the spectral roll-off characteristics of
          the RF channels composing the slice.  Figure 8 shows the
          spectral characteristics of a typical RF channel.















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                                     central channel
                                 Pc ________________
                                    |      |       |
                                    |      |       |
                                    |<-RF Channel->|
                                    |      |       |
                          Pc-Ab - -_| - - -|       |_
                                  / |      |       | \
                                 /  |      |       |  \
                                /   |      |       |   \
                               /    |      |       |    \skirt
                              /     |      |       |     \
                             /      |      |       |      \
                      Pc-Af /       |      |       |       \ floor
                      ---------------------------------------------
                                    |      |       |
                                    |      |       |
                 -------------------|------|-------|----------------------
                                 Fc-B/2    Fc      Fc+B/2


                         Figure 8: An Example RF Channel Spectral Envelope



          In Figure 8, Fc is the carrier frequency of the RF channel and
          B is the nominal bandwidth of the central channel (or the pass
          band).  The central channel is the region which has flat gain
          and is characterized by three parameters; the signal power
          level Pc, carrier frequency Fc, and the channel bandwidth B.
          Beyond the central channel, is the "skirt" (also referred to
          as transition band) of the channel's spectral characteristic.
          The skirt details the spectral roll-off characteristics
          between the central channel and the "floor" (also referred to
          as stop band).  The skirt is typically convex in shape.  Ab is
          the spectral attenuation at the band of the central channel's
          band edge.  It is measured relative to the power level of the
          central channel. Note that all attenuations and power levels
          refer to the power measured in a small band, typically less
          than 10 kHz and whose center frequency is placed at the
          frequency of interest.  For instance, the power measured in a
          5 kHz band centered at the Fc+B/2 will be Ab dB below Pc, the
          power measured in the same 5 kHz band centered at the carrier
          frequency.  Af is the attenuation of the "floor" relative to
          the power measured in the central or pass band.




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          The RF spectrum slice edge characterization is based on the
          typical RF channel spectral envelope.  The RF slice spectral
          envelope is approximated by three points; one in the skirt
          region to provide a better spectral fit to a typical RF
          spectral roll-off characteristics and the other two points to
          approximate the spectral envelope from the slice edge to the
          floor.  The parameters used to specify this spectral envelope
          are shown in Figure 9 and are described in Table 1.



                                   P_______//________
                                    |               |
                                    |               |
                                    |<-RF Spectrum->|
                                    |    Slice      |
                                    |               |
                                    |               |
                          P-Ae ---->-----------------
                                   /|               |\
                                  / |               | \
                                 |  |               |  |
                       P-Am ---> -----------------------
                                /|  |               |  |\
                               / |  |               |  | \
                              /  |  |               |  |  \
                             /   |  |               |  |   \
                            /    |  |               |  |    \
                           |     |  |               |  |     |
                  P-Af ---> ----------------------------------
                           |     |  |               |  |     |
                           |     |  |               |  |     |
                 ----------------------------------------------------
                       Fl-Ff  Fl-Fm Fl              Fu Fu+Fm Fu+Ff


                         Figure 9: RF Spectrum Slice Edge Envelope



          It is assumed that the shape of the spectral slice envelope
          does not change with the position of the slice in the RF
          spectrum and the slice bandwidth.  It is also assumed that all
          possible skirt widths will be taken into considerations when
          defining the edge envelope parameters for the reference
          spectrum slice.





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                 Table 1 - RF Spectrum Slice Edge Envelope Parameters

            _____________________________________________________________
            |             |                                    |        |
            | Parameter   | Description                        |Units   |
            |_____________|____________________________________|________|
            |_____________|____________________________________|________|
            |             |                                    |        |
            |    Ae       |The relative attenuation measured at| dB     |
            |             |the RF spectrum slice pass band     |        |
            |             |edge*.                              |        |
            |___________________________________________________________|
            |             |                                    |        |
            |    Am       |The relative attenuation measured at| dB     |
            |             |the midpoint of the spectral skirt*.|        |
            |___________________________________________________________|
            |             |                                    |        |
            |    Fm       |The skirt midwidth.  The absolute   | Hz     |
            |             |frequency difference from the slice |        |
            |             |edge frequency to the skirt's       |        |
            |             |midpoint.                           |        |
            |___________________________________________________________|
            |             |                                    |        |
            |    Af       |The relative attenuation measured at|        |
            |             |the RF spectrum slice skirt's edge*.| dB     |
            |___________________________________________________________|
            |             |                                    |        |
            |    Ff       |The skirt width.  The absolute      | Hz     |
            |             |frequency difference from the slice |        |
            |             |edge frequency to the beginning of  |        |
            |             |the spectral floor.                 |        |
            |___________________________________________________________|

            *All spectral powers are measured in a band no wider than
             10 kHz whose center frequency is at the frequency of interest.


          The attenuations at the slice spectral edge are measured
          relative to the signal power level P of the pass band of the
          typical spectral slice.  The slice pass band is assumed to
          operate in the region that has flat gain.  The SMA will
          allocate the transmit power level P to different vendors'
          products based on the power budget of each physical HFC
          subnetwork and the technical specifications provided by each
          vendor.  In addition, the SMA will use the slice spectral






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          roll-off characteristics information provided in the MIB
          (e.g., via the parameters in Table 1) to efficiently stack
          different spectral slices (belonging to different product
          classes) in the HFC subnetworks.  Note that the relative power
          tolerance of neighboring slices will depend on the parameters
          listed in Table 1 as well as the absolute power levels at
          which the vendor's products will be operating.

          Please note that this document or the csmi MIB definition does
          not specify the test procedures and the product acceptance
          policies that will be required from the vendors.  If needed,
          this information may be provided in a separate document.


          8.5.  Product Classes

          A physical HFC subnetwork supports both analog and digital
          services.  Different vendors' products are used to provide
          analog and digital services over HFC subnetworks.  A vendor
          product used to provide digital services is referred to as
          digital product class.  Digital product classes may support
          broadcast one-way, and switched (Connectionless (CNLS) and
          Connection-Oriented (CON)) two-way symmetric and asymmetric,
          digital services in the HFC subnetwork. SMA allocates RF
          spectrum to different digital product classes in a physical
          HFC subnetwork via the csmi.  Examples of product classes
          supporting digital services include digital telephony product,
          High Speed Cable Data Service (HSCDS) product, switched
          digital service (e.g., Integrated Services Digital Network
          (ISDN) services) product, and interactive multimedia service
          product.  As mentioned earlier, in the context of RF spectrum
          management, product classes are distinguished by the transport
          technology used.  For example, even though both POTS and the
          ATM service products may support voice service, product
          supporting POTS is distinguished from the ATM service product
          by the transport technology used.

          Each digital product class supported by a logical HFC
          subnetwork may be allocated either an RF spectrum slice or an
          RF channel depending on the modulation techniques or the RF
          channel types used for that product class.  Different RF
          spectrum slices (or RF channels) are allocated in the forward
          and reverse directions.  Therefore, different types of RF
          spectrum slices (or RF channels) may be allocated to a given
          product class in the forward and reverse directions of a






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          logical HFC subnetwork (i.e., RF channels and the modulation
          techniques may be different in the two directions).  As an
          example, digital telephony product may be supported using the
          64 QAM modulation technique in the forward RF channels and the
          QPSK modulation technique in the reverse RF channels.

          As mentioned above, depending on product class requirements,
          different digital product classes may be supported using
          different modulation techniques.  Also, different vendors'
          logical RF access networks may use different modulation
          techniques for their product classes to provide the same
          digital service, such as digital video service.  An example
          network access architecture supporting multiple products using
          different modulation techniques is shown in Figure 10.











































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      |
      |UPSTREAM  |/|            DOWNSTREAM (Forward)
      |(Reverse) |/|
      |          |/|
      |          |/|                     64 QAM
      |          |/| AM-VSB              Digital  64 QAM        QPSK
      |          |/| Analog Video        Data     Digital Video Telephony
      |          |/| Product             Product  Product       Product
      |          |/|-----------------------|-----|-------------|---------|
      |          |/|                       |     |             |         |
      |          |/|                       |     |             |         |
      |          |/|                       |     |             |         |
      |          |/|                       |     |             |         |
      |          |/|                       |     |             |         |

 ----|----------|/|-----------------------|-----|-------------|---------|---=
---->
      0           50                      550   560           700       750
 MHz
      |          |
      |          |
      |          |
      |          |                                      |
      |          |--------------------------------------|
                                                        |
                                                        |
      |       16 QAM            QPSK         QPSK       |
      |       Digital           Data         Telephony  |
      |    Video Product        Product       Product   |
      |       |---|            |----------|-------------|
      |       |   |            |          |             |
      |       |   |            |          |             |
      |       |   |            |          |             |
  ----|-------|---|------------|----------|-------------|-------->
      0       6   8            10        25            40   MHz


          AM-VSB - Amplitude Modulated Vestigial Side Band
          QAM - Quadrature Amplitude Modulated
          QPSK - Quaternary Phase Shift Keying


Figure 10 : An Example of RF Frequency Assignment Over a Physical HFC=
 Subnetwork









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          9.  RF Spectrum Management MIB Overview

          RF spectrum management objects are used to manage RF spectrum
          allocation to different product classes in the logical HFC
          subnetworks via the csmi.  This section provides an overview
          and background of how to use this MIB and other potential MIBs
          for this purpose.  This section also describes the RF spectrum
          management architecture hierarchy that is used to structure
          the MIB.

          In addition to the MIB module defined in this memo, MIB II
          (RFC 1213) is also used for RF spectrum management.

          9.1.  RF Spectrum Management Architecture Hierarchy

          The RF spectrum management architecture hierarchy shown in
          Figure 11 is used to structure the RF spectrum management MIB.



                           Logical RF Access Network (provided by a vendor)
                                                |
                                                |
                                                |
                                  ----------------------------------
                                   |               |              |
                                   |               |              |
                               logical HFC       logical HFC     logical HFC
                               subnetwork        subnetwork      subnetwork
                       (forward or reverse) (forward or reverse) (forward or=
 reverse)
                                      |
                                      |
                             -----------------------
                             |         |           |
                             |         |           |
                           product    product     product
                           class      class       class
                             |
                             |
                        -------------------
                        |                 |
                        |                 |
                    RF spectrum      RF spectrum
                    slice            slice


         Figure 11: RF Spectrum Management Architecture Hierarchy




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          As shown in Figure 11, the RF spectrum management architecture
          consists of the following hierarchy:


             - a logical RF access network supported by a specific vendor's
               equipments

             - logical HFC subnetworks supported by the logical RF access
               network overlaid over a physical HFC subnetwork. Logical
               HFC subnetworks in the forward and reverse directions are
               considered as separate networks.

             - product classes supported by a logical HFC subnetwork to=
 provide
               digital services

             - RF spectrum slices supported for each product class



          9.2.  Application of MIB II to Spectrum Management

          9.2.1.  The System Group

          Use the System Group to apply to the SNMP proxy-agent, SMPA.
          Each logical RF access network implements an SMPA to support
          RF spectrum allocation to services in its logical HFC
          subnetworks.  System Group applies to only one system.  This
          group is not instantiated.


          o Requirement(5) - The System Group from MIB II (RFC 1213) shall
                             apply to the Spectrum Management Proxy Agent
                             (SMPA).


          Object          Descriptions
         3D=3D=3D=3D=3D=3D         3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D

          sysDescr:     ASCII string describing the SNMP proxy-agent
                        (i.e., the SMPA).
                        Can be up to 255 characters long. This field is
                        generally used to indicate the full name and version
                        identification of the system supported. In addition,
                        the description may include information on the
                        vendor's RF access network including the vendor's
                        name.






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          sysObjectID:  Unique OBJECT IDENTIFIER (OID) for the SNMP=
 proxy-agent.

          sysUpTime:    Clock in the SNMP proxy-agent; TimeTicks in 1/100s
                        of a second.  Elapsed type since the proxy-agent
                        came on line.

          sysContact:   Contact for the SNMP proxy-agent.  ASCII string of
                        up to 255 characters.

          sysName:      Domain name of the SNMP proxy-agent, for example,
                        acme.com

          sysLocation:  Location of the SNMP proxy-agent.  ASCII string of
                        up to 255 characters.

          sysServices:  Services supported by the RF access networks.
                        Since the RF access networks may simultaneously
                        support a number of services at different protocol
                        layers of the Open Systems Interconnection (OSI)
                        protocol stack (e.g., POTS, cable data service,
                        digital broadcast video), the value "0" is used
                        for RF spectrum management purposes.

          In addition, the SMPA must support coldStart and
          authenticationFailure traps from RFC1157 to indicate
          respectively the SMPA restart after a failure and the SNMP
          message received by the SMPA that did not pass authentication
          verification.

          o Requirement(6) - The Spectrum Management Proxy Agent (SMPA)=
 shall
                             support coldStart and authenticationFailure=
 traps
                             from RFC 1157 to indicate respectively the SMPA
                             restart (e.g., after a failure), and that the=
 SNMP
                             messages did not pass the authentication
                             verification.


          9.3.  Structure of the RF Spectrum Management MIB

          The managed objects are arranged into the following SNMP
          tables:


               (1) Logical HFC subnetwork table
               (2) Product class table
               (3) RF spectrum slice configuration table





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          There is a one-to-one map between the logical HFC subnetworks
          in a logical RF access network and the physical HFC
          subnetworks. Therefore, the logical HFC subnetworks in a
          logical RF access network managed by the SMPA may be indexed
          the same way as the physical HFC subnetworks.  The SMA
          maintains the relationship between the logical RF access
          networks provided by different vendors' network equipments and
          the physical HFC subnetworks. For RF spectrum management
          purposes, the HFC subnetworks supported by a single optical
          transmitter (or receiver) at the DH (or HE) are considered as
          a single physical HFC subnetwork in the forward (or reverse
          direction).  The logical HFC subnetworks may be supported in
          the future using the ifTable in MIB II (RFC 1213).

          The logical HFC subnetwork table and the product class table
          contain respectively the descriptions of the logical HFC
          subnetworks and the product classes that are supported in the
          logical HFC subnetworks. The logical HFC subnetwork table also
          contains descriptions of the physical HFC subnetworks to which
          a vendor's logical HFC subnetworks belong.  The product class
          table also contains description of the RF technology supported
          by a vendor for each type of product class.

          The SMA can use the RF spectrum slice configuration table to
          create, delete, or modify RF spectrum slices containing single
          or multiple RF channels depending on the vendor's RF
          technology.  To configure or reconfigure an RF spectrum slice,
          the SMA uses the RF information template provided in the
          product class table for each product class.

          As mentioned earlier, frequency block conversion method is
          used for efficiently utilizing the reverse RF spectrum.  In
          the future, frequency block conversion may also be used in the
          forward direction.  Each block converter is modeled as a
          separate physical HFC subnetwork (and therefore as a separate
          logical HFC subnetwork).

          Some vendor technologies may support RF channels as dynamic
          resources and assign an RF channel to a subscriber on a
          dynamic basis via session establishments.  For example, some
          vendor technologies may use RF channels of very narrow band
          such as 50 kHz, using Frequency Division Multiplexing (FDM)
          technique.  In contrast, other vendor technologies may support
          allocation of a portion of the RF channel bandwidth (e.g.,
          DS0s within a 6 MHz RF channel) to a subscriber on a session






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          by session basis (e.g., by using Time Division Multiplexing
          (TDM) technique and subchannel configurations).  Therefore,
          the RF spectrum slice table can be used to configure an RF
          spectrum slice containing either a single or multiple RF
          channels depending on the RF technology supported for a
          specific product class.  Therefore, an RF spectrum slice may
          contain a single RF carrier or multiple RF carriers.

          Therefore, SMA can allocate RF spectrum to a product in the
          following fashions:

            - single or multiple non-contiguous RF channels (each
              RF channel containing a single RF carrier)

            - single or multiple non-contiguous RF spectrum slices (each=
 slice
              containing multiple RF channels, i.e., multiple RF carriers)


          For example, SMA may allocate RF frequency spectrum to a
          product class in two different RF spectrum slices (e.g., one
          from 10-14 MHz and the other from 26-30 MHz) using four RF
          channels of each 1 MHz size (allocated to each RF spectrum
          slice), as shown in Figure 12.  Note that RF channels can be
          moved to a different carrier frequency within the slice if a
          portion of the slice becomes unusable.




                             4 RF Channels            4 RF Channels
                             ^   ^   ^   ^            ^   ^   ^   ^
                           | |   |   |   | |        | |   |   |   | |
                           | |   |   |   | |        | |   |   |   | |

 ---------|-|-|-|-|-|-|-|-|--------|-|-|-|-|-|-|-|-|--------
                           |               |        |               |
                         10MHz<--------->14MHz    26MHz<---------->30MHz
                                Slice 1                   Slice 2


                 Figure 12: An Example of RF Spectrum Slice Allocation



          Table 2 lists the objects that are relevant for RF spectrum
          management.  The table also shows the RF spectrum
          configuration parameters that are configurable via the csmi.





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                        Table 2 - RF Spectrum Management Objects


 _________________________________________________________________________
       |                   |                                 |
   |
       | Management        | Managed Objects                 |Note
   |
       | Information       |                                 |
   |

 |___________________|_________________________________|_________________|

 |___________________|_________________________________|_________________|
       |Logical HFC        |(1)logical subnetwork address    |
   |
       |subnetwork         |(2)logical subnetwork description|
   |
       |information        |(3)physical network description  |
   |
       |                   |(4)block conversion support      |
   |

 |_______________________________________________________________________|
       |Product class/RF   |(1)product class type            |
   |
       |channel information|(2)product class description     |
   |
       |                   |(3)RF modulation technique       |
   |
       |                   |(5)RF channel data rate          |
   |
       |                   |(6) minimum modulation order     |
   |
       |                   |(7) maximum modulation order     |
   |
       |                   |(8) modulation order step size   |
   |
       |                   |(9)RF channel minimum frequency  |
   |
       |                   |(10)RF channel maximum frequency |
   |
       |                   |(11)RF channel frequency step    |
   |
       |                   |    size                         |
   |
       |                   |(12)RF channel minimum power     |
   |
       |                   |    level                        |
   |
       |                   |(13)RF channel maximum power     |
   |
       |                   |    level                        |
   |
       |                   |(14)RF channel power level step  |
   |
       |                   |    size                         |
   |
       |                   |(15)RF channel desired modulation|
   |
       |                   |    order                        |
   |
       |                   |(16)RF slice skirt transmit      |
   |
       |                   |    attenuation                  |
   |
       |                   |(17)RF slice skirt edge transmit |
   |
       |                   |    attenuation                  |
   |
       |                   |(18)RF slice skirt bandwidth     |
   |
       |                   |(19)RF slice skirt midbandwidth  |
   |

 |_____________________________________________________|_________________|











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                        Table 2 - RF Spectrum Management Objects (cont.)


 _________________________________________________________________________
       |                   |                                 |
   |
       | Management        | Managed Objects                 |Note
   |
       | Information       |                                 |
   |

 |___________________|_________________________________|_________________|

 |___________________|_________________________________|_________________|
       |                   |(20)RF slice envelope edge       |
   |
       |                   |    transmit attenuation         |
   |
       |                   |(21)RF slice received sensitivity|
   |
       |                   |    level from adjacent slices'  |
   |
       |                   |    skirts                       |
   |
       |                   |(22)RF slice edge received       |
   |
       |                   |    sensitivity level            |
   |
       |                   |                                 |
   |

 |_____________________________________________________|_________________|
       |RF spectrum slice  |(1)RF spectrum slice identifier  |The parameters=
 5,|
       |(or RF channel)    |(2)Operational status            |6,7, & 8 are
   |
       |configurable       |(3)Administrative status         |configurable=
 per |
       |parameters         |(4)Last change status            |RF slice or RF=
   |
       |                   |(5)Slice modulation order        |channel=
 depending|
       |                   |(6)Slice upper frequency         |on the RF=
 techno-|
       |                   |(7)Slice lower frequency         |logy used for=
 a  |
       |                   |(8)Slice transmit power level    |specific=
 product |
       |                   |                                 |class.
   |

 |___________________|_________________________________|_________________|
























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          10.  Definitions

               COMMON-SPECTRUM-MANAGEMENT-INTERFACE-MIB DEFINITIONS ::=3D=
 BEGIN

               IMPORTS
                  OBJECT-TYPE
                            FROM RFC-1212
                  enterprises, TimeTicks
                            FROM RFC1155-SMI
                  DisplayString
                            FROM RFC1213-MIB
                  EntryStatus
                            FROM RFC1271-MIB
                  TRAP-TYPE
                            FROM RFC-1215;

               -- This MIB module uses the extended OBJECT-TYPE macro as
               -- defined in RFC1212 and the TRAP-TYPE macro as defined
               -- in RFC 1215.

         -- This is the MIB module to manage Radio Frequency (RF) spectrum
         -- of the logical Hybrid Fiber Coax (HFC) subnetworks via the
         -- common spectrum management interface (csmi).

               twcable      OBJECT IDENTIFIER ::=3D {enterprises 1174}

               requirements OBJECT IDENTIFIER ::=3D {twcable 1 }

               csmirequirements OBJECT IDENTIFIER ::=3D {requirements 1 }


               csmiMIB  OBJECT IDENTIFIER ::=3D {csmirequirements 1}

               csmiMIBObjects  OBJECT IDENTIFIER ::=3D {csmiMIB 1}




       -- This MIB module contains logical Hybrid Fiber Coax (HFC)=
 subnetwork
       -- group, product class group, and the RF spectrum slice group.
       -- The logical HFC subnetwork group contains descriptions of
       -- the logical HFC subnetworks and the associated physical HFC
       -- subnetworks.
       -- The product class group contains descriptions of different
       -- vendors' products supporting digital services and the
       -- associated RF channel types.






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               -- The RF spectrum slice group consists of the RF spectrum=
 slice
               -- configuration table which is used for creating, deleting,
               -- and modifying RF spectrum slices containing a single or
               -- multiple RF channels.












































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               csmiProductClassTypes  OBJECT IDENTIFIER ::=3D=
 {csmiMIBObjects 1}

               -- The following values are defined for use as
               -- possible values of the digital product class types that=
 will
               -- be supported in the hybrid fiber coax systems.  Examples
               -- of digital product classes include telephony service
               -- product, high speed data service product, and
               -- interactive multi-media service product.
               -- In the context of RF spectrum management, the product
               -- classes are distinguished by the technology used
               -- and not by the services supported by these product=
 classes.
               -- For example, POTS product class is distinguished
               -- from the ATM product class by the transport technology=
 used
               -- even though both POTS and the ATM product classes
               -- may support voice service.


               csmiNoProduct  OBJECT IDENTIFIER ::=3D {=
 csmiProductClassTypes 1}
               -- No product class.

              csmiUnknownProduct  OBJECT IDENTIFIER ::=3D
                                  { csmiProductClassTypes 2}
               -- An unknown product class.

               csmiPOTSProduct  OBJECT IDENTIFIER ::=3D {=
 csmiProductClassTypes 3}
               -- Plain Old Telephone Service Product.

               csmiHighSpeedCableDataServiceProduct  OBJECT IDENTIFIER ::=3D
                                                   { csmiProductClassTypes=
 4}
               -- High speed cable data service product class.

               csmiSwitchedDigitalServiceProduct  OBJECT IDENTIFIER ::=3D
                                                  { csmiProductClassTypes 5}
               -- Switched digitial service product class may include
               -- Integrated Digital Service Network (ISDN) service
               -- products and other voice service products.

               csmiUtilityCommunicationsServiceProduct  OBJECT IDENTIFIER=
 ::=3D
                                                   { csmiProductClassTypes=
 6}
               -- Utility communications service product
               -- supporting services such as telemetry service.

               csmiConverterStatusMonitoringProduct  OBJECT IDENTIFIER ::=3D
                                                 { csmiProductClassTypes 7}
               -- Network Interface Unit (NIU) status monitoring
               -- product class.

               csmiInteractiveMultimediaServiceProduct  OBJECT IDENTIFIER=
 ::=3D
                                                    { csmiProductClassTypes=
 8}
               -- Interactive multimedia service product class
               -- supporting services such as interactive

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               -- game/shopping/education service.

               csmiVideoOnDemandServiceProduct  OBJECT IDENTIFIER ::=3D
                                            { csmiProductClassTypes 9}
               -- Video on demand service product class.

               csmiTransponderCommunicationsProduct OBJECT IDENTIFIER ::=3D
                                                  { csmiProductClassTypes=
 10}
               -- Transponder communications product class
               -- supporting services such as satellite digital
               -- broadcast service.

            csmiIEEE80214Product OBJECT IDENTIFIER ::=3D
                                       { csmiProductClassTypes 11}
               -- An IEEE 802.14 based product class
               -- which supports a number of services
               -- such as voice, video and data based on IEEE 802.14=
 standards.

               csmiATMProduct OBJECT IDENTIFIER ::=3D {=
 csmiProductClassTypes 12}
               -- ATM product class.


               csmiVendorSpecificProduct OBJECT IDENTIFIER ::=3D
                                                  { csmiProductClassTypes=
 13}
               -- A vendor specific product class which supports
               -- vendor specific services.


























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               csmiModulationTypes  OBJECT IDENTIFIER ::=3D {csmiMIBObjects=
 2}

               -- The following values are defined for use as
               -- possible values of the modulation techniques that may be
               -- supported in the hybrid fiber coax systems.  Examples
               -- of different modulation techniques include QAM, PSK,
               -- QPR, spread spectrum, and VSB.


               csmiNoModulation      OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 1}
               -- No modulation technique.

               csmiUnknownmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 2}
               -- Modulation technique that is not known.

               csmiQAMmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 3}
               -- Quadrature amplitude modulation (QAM) technique

               csmiVSBmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 4}
               -- Vestigial Side Band (VSB) modulation technique

               csmiPSKmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 5}
               -- Phase shift key (PSK) modulation technique

               csmiDPSKmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 6}
               -- Differential phase shift key (DPSK) modulation technique

               csmiOFDMmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 7}
               -- Orthogonal frequency division modulation (OFDM) technique

               csmiQPRmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 8}
               -- Quadrature partial response (QPR) modulation technique

               csmiQPSKmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 9}
               --  Quaternary phase shift key (QPSK) modulation technique

               csmiDQPSKmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 10}
               -- Differential quaternary phase shift key (DQPSK)
               -- modulation technique

               csmiFSKmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 11}
               -- Frequency shift key (FSK) modulation technique

               csmiASKmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 12}
               -- Amplitude shift key (ASK) modulation technique







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               csmiOPSKmodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 13}
               -- Offset phase shift key (OPSK) modulation technique

               csmiNonSynSpreadSpectrummodulation OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 14}
               -- Non-synchronous spread spectrum modulation technique

               csmiSynchSpreadSpectrummodulation  OBJECT IDENTIFIER ::=3D
                                        { csmiModulationTypes 15}
               -- Synchronous spread spectrum modulation technique
















































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               --    Logical HFC Subnetwork Configuration Table

               -- This table contains descriptions of the logical
               -- Hybrid Fiber Coax (HFC) subnetworks that are supported
               -- by the RF Spectrum Management Proxy Agent (SMPA).
               -- Note that the address and description=CAfields for a
               -- subnetwork will be set by the SMA, but the direction
               -- and block converter shift fields are read only.
               -- The SMPA should communicate if the direction is forward
               -- or reverse, as well determine the block conversion
               -- frequencies (if any) by interactions with the network
               -- and the terminal devices of each product.

               -- Implementation of this group is mandatory if
               -- providing RF spectrum management.

               logicalHfcSubnetworkTable    OBJECT-TYPE
                         SYNTAX      SEQUENCE OF LogicalHfcSubnetworkEntry
                         ACCESS      not-accessible
                         STATUS       mandatory
                         DESCRIPTION
                          "This table contains information on the logical
                           HFC subnetworks that are supported by the SMPA.
                           Logical HFC subnetworks in the forward direction,
                           i.e., in the network-to-subscriber direction and
                           in the reverse direction, i.e., in the
                           subscriber-to-network direction are modeled as
                           two separate HFC sub networks."
                         ::=3D { csmiMIBObjects 3 }

               logicalHfcSubnetworkEntry    OBJECT-TYPE
                         SYNTAX         LogicalHfcSubnetworkEntry
                         ACCESS         not-accessible
                         STATUS         mandatory
                         DESCRIPTION
                          "This list contains logical HFC subnetwork=
 information."
                         INDEX { logicalHfcSubnetworkIndex }
                         ::=3D { logicalHfcSubnetworkTable 1}

               LogicalHfcSubnetworkEntry    ::=3D SEQUENCE  {
                         logicalHfcSubnetworkIndex
                            INTEGER,
                         logicalHfcSubnetworkDirection
                            INTEGER,
                         logicalHfcSubnetworkAddress
                            OCTET STRING,
                         logicalHfcSubnetworkDescription
                            DisplayString,
                         physicalHfcSubnetworkDescription


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                            DisplayString,
                         hfcBlockConversionFrequencyShift
                            INTEGER
                              }

               logicalHfcSubnetworkIndex    OBJECT-TYPE
                           SYNTAX       INTEGER (1..65535)
                           ACCESS       read-only
                           STATUS       mandatory
                           DESCRIPTION
                            "The value of this object identifies the logical
                             HFC subnetwork for which this entry contains=
 the
                             HFC subnetwork information."
                           ::=3D { logicalHfcSubnetworkEntry 1}


               logicalHfcSubnetworkDirection   OBJECT-TYPE
                           SYNTAX       INTEGER {
                                                 forward(1),
                                                 reverse(2)
                                                 }
                           ACCESS       read-only
                           STATUS       mandatory
                           DESCRIPTION
                            "The value of this object indicates whether the
                             RF spectrum supported by this logical HFC
                             subnetwork apply to the forward or reverse
                             direction. The
                             forward(1) refers to the RF spectrum apply to
                             the subscriber-to-network direction and the=
 value
                             reverse(2) refers to the RF spectrum apply to=
 the
                             network-to-subscriber direction."
                           ::=3D { logicalHfcSubnetworkEntry 2}

               logicalHfcSubnetworkAddress    OBJECT-TYPE
                           SYNTAX            OCTET STRING (SIZE(0..255))
                           ACCESS     read-write
                           STATUS     mandatory
                           DESCRIPTION
                            "An address assigned to the logical HFC=
 subnetwork
                             for administrative purposes.  If no address is
                             assigned, then this is an octet string of zero
                             length."
                           ::=3D { logicalHfcSubnetworkEntry 3}

               logicalHfcSubnetworkDescription    OBJECT-TYPE






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                           SYNTAX     DisplayString (SIZE (0..255))
                           ACCESS     read-write
                           STATUS     mandatory
                           DESCRIPTION
                            "Description of the logical HFC subnetwork.
                             The description may include vendor's name, the
                             Distribution Hub Equipment (DHE) name, and the
                             version identification."
                           ::=3D { logicalHfcSubnetworkEntry 4}

               physicalHfcSubnetworkDescription    OBJECT-TYPE
                           SYNTAX     DisplayString (SIZE (0..255))
                           ACCESS     read-write
                           STATUS     mandatory
                           DESCRIPTION
                            "Description of the physical HFC subnetwork
                             to which this logical HFC subnetwork
                             belongs.  The description may include
                             full name, number of fiber nodes supported
                             per optical receiver or transmitter at the
                             Distribution Hub (DH) or Head End (HE), and
                             geographic locations of the fiber nodes or
                             the HFC subnetworks."
                           ::=3D { logicalHfcSubnetworkEntry 5}

               hfcBlockConversionFrequencyShift    OBJECT-TYPE
                           SYNTAX      INTEGER
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "This object identifies the amount of frequency
                             shift supported by the block conversion method
                             from the frequency supported on the co-axial=
 part.
                             The value can be 0, positive or negative.
                             The value 0 indicates that either block
                             conversion is not supported in the
                             HFC subnetwork or block conversion supports
                             fixed frequency shift only (current HFC
                             implementations).  The positive value
                             indicates that the frequency is shifted upward
                             from the one supported in the co-axial part of=

                             the HFC subnetwork and the value negative
                             indicates that the
                             frequency is shifted downward (possibly future
                             HFC implementations using broadband receiver
                             at the Distribution Hub).  The value is=
 expressed






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                             in units of kHz."
                           ::=3D { logicalHfcSubnetworkEntry 6}

















































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               --    Product Class Table

               -- This table contains descriptions and configuration
               -- parameters of the digital product classes and the
               -- associated Radio Frequency (RF) channel types
               -- that are supported in logical Hybrid Fiber
               -- Coax (HFC) subnetworks.

               -- This table also provides information on the
               -- RF channel types (forward or reverse)
               -- supported for the given digital product class.
               -- The digital product classes are modeled as one-way
               -- products using either forward or reverse RF channels.

               -- An RF channel associated with a given digital product
               -- class in a logical HFC subnetwork is defined
               -- as the minimum radio frequency used in a
               -- given modulation technique.

               -- The SMA uses the rfSpectrumSliceConfigTable
               -- to create, delete or modify an RF spectrum
               -- slice (containing a single or multiple RF
               -- channels) and the related configurable
               -- parameters using the RF channel information
               -- provided for a given digital product class
               -- in this table.

               -- It is possible that different digital product classes
               -- may be supported using the same RF channel type.

               -- Implementation of this group is mandatory if
               -- providing RF spectrum management.


               productClassTable    OBJECT-TYPE
                         SYNTAX      SEQUENCE OF ProductClassEntry
                         ACCESS      not-accessible
                         STATUS       mandatory
                         DESCRIPTION
                          "This table contains information on the digital
                           product classes and the associated RF channels
                           that are supported in the logical
                           HFC subnetworks."
                         ::=3D { csmiMIBObjects 4 }

               productClassEntry    OBJECT-TYPE






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                         SYNTAX     ProductClassEntry
                         ACCESS     not-accessible
                         STATUS      mandatory
                         DESCRIPTION
                          "This list contains digital product class and the
                           associated RF channel parameters and=
 descriptions."
                         INDEX { productHfcNetworkIndex, productClassIndex }
                         ::=3D { productClassTable  1}


               ProductClassEntry    ::=3D SEQUENCE  {
                         productHfcNetworkIndex
                            INTEGER,
                         productClassIndex
                            INTEGER,
                         productClassType
                            OBJECT IDENTIFIER,
                         productClassDescription
                            DisplayString,
                         rfChannelSize
                            INTEGER,
                         rfChannelDataRate
                            INTEGER,
                         rfChannelModulationType
                            OBJECT IDENTIFIER,
                         rfChannelDesiredModulationOrder
                            INTEGER,
                         rfChannelModulationMinOrder
                            INTEGER,
                         rfChannelModulationMaxOrder
                            INTEGER,
                         rfChannelModulationOrderStepSize
                            INTEGER,
                         rfChannelMinFrequency
                            INTEGER,
                         rfChannelMaxFrequency
                            INTEGER,
                         rfChannelFrequencySpectrumStepSize
                            INTEGER,
                         rfChannelMinimumPowerLevel
                            INTEGER,
                         rfChannelMaximumPowerLevel
                            INTEGER,
                         rfChannelPowerLevelStepSize
                            INTEGER,






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                         rfSliceBandEdgeAttenuation
                            INTEGER,
                         rfSliceSkirtAttenuation
                            INTEGER,
                         rfSliceEnvelopeEdgeAttenuation
                            INTEGER,
                         rfSliceSkirtMidBandwidth
                            INTEGER,
                         rfSliceSkirtBandwidth
                            INTEGER,
                         rfSliceSkirtSensitivity
                            INTEGER,
                         rfSliceEdgeSensitivity
                            INTEGER
                              }


               productHfcNetworkIndex    OBJECT-TYPE
                           SYNTAX       INTEGER (1..65535)
                           ACCESS       read-only
                           STATUS       mandatory
                           DESCRIPTION
                            "The value of this object identifies the logical
                             HFC subnetwork for which this entry contains=
 the
                             digital product class information.  The value
                             of this object for a specific logical HFC
                             subnetwork has the
                             same value as the logicalHfcSubnetworkIndex=
 defined
                             in logicalHfcSubnetworkTable for the same=
 logical
                             HFC subnetwork."
                           ::=3D { productClassEntry 1}

               productClassIndex    OBJECT-TYPE
                           SYNTAX       INTEGER (1..65535)
                           ACCESS       read-only
                           STATUS       mandatory
                           DESCRIPTION
                            "The value of this object identifies the
                             digital product class entries for this logical=
 HFC
                             subnetwork."
                           ::=3D { productClassEntry 2}

               productClassType    OBJECT-TYPE
                           SYNTAX     OBJECT IDENTIFIER
                           ACCESS     read-only
                           STATUS     mandatory






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                           DESCRIPTION
                            "The value of this object identifies the type of
                             digital product class being supported for this=

                             logical HFC subnetwork.  For example, for
                             telephony service product, the digital
                             product class type may indicate
                             'csmiPOTSProduct' for this entry."
                           ::=3D { productClassEntry 3}

               productClassDescription    OBJECT-TYPE
                           SYNTAX     DisplayString (SIZE (0..255))
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "Description of the digital product being=
 provided
                             for this logical HFC subnetwork.  The=
 description
                             may include full name, the protocol layer and=
 the
                             transport technology used, and version
                             identification
                             of the digital product class."
                           ::=3D { productClassEntry 4}


               rfChannelSize    OBJECT-TYPE
                           SYNTAX         INTEGER (1..4294967295)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object identifies the RF=
 channel
                             size supported for this product class. The=
 value is
                             expressed in kHz. An RF channel size is defined=
 as
                             the occupied RF bandwidth plus guard RF=
 bandwidth
                             for a single modulated carrier. For example,
                             the RF channel size may be 6,000 kHz.
                             The RF channel size is fixed for a given
                             modulation technique and digital product=
 class."
                           ::=3D { productClassEntry 5 }

               rfChannelDataRate    OBJECT-TYPE
                           SYNTAX      INTEGER (0..4294967295)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object provides the computed=
 data
                             rate of the RF channel supported for this=
 product
                             class based on the modulation technique and
                             the modulation order used for the RF channel=
 type.
                             The value is specified in bits per second which





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                             is computed from the spectral efficiency
                             defined in bits per second per Hz and the=
 channel
                             size defined in Hz. For example,
                             the 64QAM modulation
                             technique may support approximately 27 Mbps
                             channel data rate for a 6,000 kHz RF channel.
                             The value of this object is fixed for a given=
 order
                             of the modulation technique."
                            ::=3D { productClassEntry 6}

               rfChannelModulationType    OBJECT-TYPE
                           SYNTAX         OBJECT IDENTIFIER
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object identifies the type
                             of RF channel modulation technique used for=
 this
                             digital product class.  For example, the
                             RF modulation technique supported for this=
 product
                             class is QPSK.  The value of this object is
                             fixed for a given
                             RF channel type associated with a given
                             digital product class."
                           ::=3D { productClassEntry 7 }


               rfChannelDesiredModulationOrder    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object identifies the desired
                             modulation order for the RF channel supported=
 for
                             this product class.  The value is expressed
                             as the exponent of a power of two.  For=
 example,
                             the desired modulation order for the RF channel
                             may be 8 (e.g. 64QAM)."
                           ::=3D { productClassEntry 8}


               rfChannelModulationMinOrder    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object identifies the minimum
                             modulation order supported for the RF channel
                             associated with the digital product class.
                             For example, the minimum Quadrature Amplitude




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                             Modulation (QAM) order that may be supported=
 for
                             this RF channel is 16QAM.  The
                             rfChannelModulationMinOrder
                             and the rfChannelModulationMaxOrder have the=
 same
                             values when the modulation order cannot changed
                             for this RF channel type.  The value of this
                             object is fixed for a given RF channel type
                             associated with a digital product class."
                           ::=3D { productClassEntry 9 }

               rfChannelModulationMaxOrder    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object identifies the maximum
                             modulation order supported for the RF channel
                             associated with the digital product class.
                             For example, the maximum Quadrature Amplitude
                             Modulation (QAM) order that may be supported=
 for
                             this RF channel is 256QAM.  The=
 rfChannelModulationMinOrder
                             and the rfChannelModulationMaxOrder have the=
 same
                             values when the modulation order cannot be=
 changed
                             for this RF channel type.  The value of this
                             object is fixed for a given RF channel type
                             associated with a digital product class."
                           ::=3D { productClassEntry 10 }


               rfChannelModulationOrderStepSize    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object identifies the minimum
                             step size supported for modifying the RF
                             modulation order.  The value is expressed
                             as the exponent of a power of two.  For=
 example,
                             the minimum step size that may be used to=
 change an
                             existing modulation order (e.g., 32QAM) is 4.
                             Thus, in this case, the modulation order may be=
 changed
                             to 16QAM, 64QAM or 256QAM."
                           ::=3D { productClassEntry 11 }








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               rfChannelMinFrequency    OBJECT-TYPE
                           SYNTAX         INTEGER (0..4294967295)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object identifies the minimum
                             radio carrier frequency supported for the RF
                             spectrum channel associated with the digital
                             product class.
                             The value of this object is specified in kHz.
                             For example, the minimum RF carrier frequency
                             that may be supported for the RF spectrum=
 channel
                             is 54,000 kHz.  The rfChannelMaxFrequency and=
 the
                             rfChannelMinFrequency have the same values when
                             the carrier frequency cannot be changed for=
 this RF
                             channel type. The value of this object is fixed=
 for
                             a given RF channel type associated with a=
 digital
                             product class."
                           ::=3D { productClassEntry 12 }

               rfChannelMaxFrequency    OBJECT-TYPE
                           SYNTAX         INTEGER (0..4294967295)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object identifies the maximum
                             radio carrier frequency supported for the RF
                             spectrum channel associated with the digital
                             product class.
                             The value of this object is specified in kHz.
                             For example, the maximum RF carrier frequency
                             that may be supported for the RF spectrum=
 channel
                             is 750,000 kHz.  The rfChannelMaxFrequency and=
 the
                             rfChannelMinFrequency have the same values when=
 the
                             carrier frequency cannot be changed for this RF
                             channel type. The value of this object is fixed
                             for a given RF channel type associated
                             with a digital product class."
                           ::=3D { productClassEntry 13 }


               rfChannelFrequencySpectrumStepSize    OBJECT-TYPE
                           SYNTAX         INTEGER (0..4294967295)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object identifies the minimum
                             step size that can be used to change the
                             carrier frequency





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                             of the RF channel associated with the digital
                             product class.  The value is expressed in kHz.
                             Typically, the step size is less than 250 kHz
                             in the forward direction, i.e., in the
                             network-to-subscriber direction and less
                             than 100 kHz in the reverse direction,
                             i.e., in the subscriber-to-network
                             direction."
                           ::=3D { productClassEntry 14 }


               rfChannelMinimumPowerLevel    OBJECT-TYPE
                           SYNTAX         INTEGER
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the minimum
                             transmit power level setting allowed for the RF
                             channel associated with the digital product
                             class.  The power level is expressed in dBmV.
                             For example, the minimum power level that may
                             be supported for the RF channel is 20 dBmV.
                             If the rfChannelMinimumPowerLevel and
                             rfChannelMaximumPowerLevel have the same
                             values then the power level is fixed for this=
 RF
                             channel and cannot be changed by the SMA. For=
 the
                             forward RF spectrum direction, the value of=
 this
                             object indicates the minimum transmit power=
 level
                             measured at the Distribution Hub Equipment in=
 the HFC
                             subnetwork.  For the reverse RF spectrum=
 direction,
                             the value of this object indicates the minimum
                             transmit power level measured at the cable=
 modem at
                             the subscriber's premises. The value of this=
 object
                             is fixed for a given RF channel associated with=
 a
                             digital product class."
                           ::=3D { productClassEntry 15}

               rfChannelMaximumPowerLevel    OBJECT-TYPE
                           SYNTAX         INTEGER
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the maximum
                             transmit power level setting allowed for the RF
                             channel associated with a given digital product
                             class. The power level is expressed in dBmV.






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                             For example, the maximum power level that may
                             be supported for this RF channel is 20 dBmV.
                             If the rfChannelMinimumPowerLevel and
                             rfChannelMaximumPowerLevel have the same
                             values then the power level is fixed and
                             cannot be adjusted for this RF channel. For the
                             forward RF spectrum direction, the value of=
 this
                             object indicates the maximum transmit power=
 level
                             measured at the Distribution Hub Equipment in=
 the
                             HFC subnetwork.  For the reverse
                             RF spectrum direction,
                             the value of this object indicates the maximum
                             transmit power level measured at the cable=
 modem at
                             the subscriber's premises. The value of this=
 object
                             is fixed for a given RF channel associated with=
 a
                             digital product class."
                           ::=3D { productClassEntry 16 }

               rfChannelPowerLevelStepSize    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the minimum
                             step size (in absolute value) supported for the
                             power level setting.  The value is
                             expressed in dBmV. For example, the step size
                             may be 1 dBmV by which the power level may be
                             changed."
                           ::=3D { productClassEntry 17 }

               rfSliceBandEdgeAttenuation    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the relative=

                             power at the edge of the RF spectrum slice pass
                             bandwidth.  The power level is measured=
 relative
                            to the transmit power level of the slice pass=
 band.
                            The value is expressed in dB.  The value of this
                            object is assumed to be independent of the pass=

                            band of the typical RF spectrum slice supported
                            for this digital product class. The value of
                            this object should be measured in
                            a 10 kHz band whose center frequency is at the=

                            frequency of interest.  For example, the power
                            measured in a 10 kHz band centered at the 30 MHz





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                             is 20 dB below transmit the power measured in=
 the
                             same 10 kHz band centered at the slice pass=
 band
                             center frequency of 27 MHz."
                           ::=3D { productClassEntry 18 }

               rfSliceSkirtAttenuation    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the power
                             level at the midpoint in the RF spectrum slice
                             skirt or transition band relative to the=
 transmit
                             power level at the slice pass band.  The skirt=

                             details the roll-off characteristics between=
 the
                             central portion of the RF spectrum slice and=
 the
                             edge of the slice. The value is expressed in=
 dB.
                             The value of this object is assumed to be
                             independent of the position of the RF spectrum
                             slice in the RF spectrum. The value of this
                             object should be measured in a 10
                             kHz band whose center frequency is at
                             the frequency of interest.  For example,
                             the power measured in a 10 kHz band centered
                             at thefrequency such as 32 MHz is 40 dB below
                             the transmit power measured in the same
                             10 kHz band centered at the slice pass
                             band center frequency of 27 MHz."
                           ::=3D { productClassEntry 19 }

               rfSliceEnvelopeEdgeAttenuation    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the power
                             level at the edge of the RF spectrum slice
                             envelope relative to the transmit power level
                             at the slice pass band.  The value is expressed=
 in
                             dB. The value of the object is assumed to be
                             independent of the position of the RF spectrum
                             slice on the RF spectrum.  The value of this
                             object should be measured in a 10 kHz band=
 center
                             frequency is at the frequency of interest.
                             For example, the power measured in a 10 kHz
                             band centered at the frequency
                             such as 35 MHz is 60 dB below the transmit=
 power
                             measured in the same 10 kHz band centered at=
 the
                             slice pass band center frequency of 27 MHz."





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                           ::=3D { productClassEntry 20 }


               rfSliceSkirtMidBandwidth    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the=
 bandwidth
                             of the mid point of the RF spectrum slice skirt
                             (also referred to as transition band).  It is=
 the
                             absolute frequency difference between the slice
                             edge frequency and the skirt's midpoint=
 frequency.
                             The skirt details the roll-off characteristics
                             between the central portion of the RF spectrum=

                             slice and the edge of the slice.  The value
                             is expressed in kHz.  For example,
                             the value may be 2,000 kHz."
                           ::=3D { productClassEntry 21 }


               rfSliceSkirtBandwidth    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the=
 bandwidth
                             of the skirt at the edge of the RF spectrum=
 slice
                             envelope.  It is the absolute frequency=
 difference
                             between the slice edge frequency and the=
 beginning
                             of the spectrum slice floor (also referred to=
 as
                             stop band).  The value is expressed in kHz.
                             For example, the value may be 5,000 kHz."
                           ::=3D { productClassEntry 22 }

               rfSliceSkirtSensitivity    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the relative
                             power level sensitivity of the typical RF=
 spectrum
                             slice associated with the digital product=
 class.
                             It provides the tolerance of the slice to the=
 power
                             received from all interfering signals from the=

                             skirts of the adjacent spectrum slices
                             associated with






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                             different product classes measured relative to=
 the
                             receive power level of the slice pass band.
 The
                             value is expressed in dB. The value of this=
 object
                             is assumed to be independent of the position
                             of the RF slice in the RF spectrum.
                             The value of this object
                             should be measured in a 10 kHz band whose=
 center
                             frequency is at the frequency of interest.  For=

                             example, the power measured in a 10 kHz
                             band centered at 32 MHz is 30 dB below the
                             receive power measured in the same 10 kHz
                             band centered at the slice pass
                             band frequency at 27 MHz."
                           ::=3D { productClassEntry 23 }


               rfSliceEdgeSensitivity    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the relative
                             power level sensitivity of the RF spectrum=
 slice
                             associated with this digital product class.
                             It provides the tolerance level of the slice=
 from
                             the power received from all interfering signals
                             from the adjacent spectrum slices associated=
 with
                             different product classes measured relative
                             to the receive signal power level of the slice=
 pass
                             band.  The value is expressed in dB. The value=
 of
                             this object is assumed to be independent of the
                             position of the RF spectrum slice in the RF
                             spectrum.  The value of this object should be
                             measured in a 10 kHz band whose center=
 frequency
                             is at the frequency of interest.  For example,
                             the power measured in a 10 kHz band centered
                             at 35 MHz is 60 dB below the receive power
                             measured in the same 10 kHz band
                             centered at the slice pass band
                             frequency at 27 MHz."
                           ::=3D { productClassEntry 24 }














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               --    RF Spectrum Slice Configuration Table

               -- This table contains the configuration and state
               -- information of a Radio Frequency (RF) spectrum slice
               -- associated with a given digital product class supported
               -- in the logical Hybrid Fiber Coax (HFC) subnetwork.

               -- For the purpose of RF spectrum management, RF spectrum
               -- slice is defined as the RF frequency spectrum interval
               -- associated with a group of fine-grained modulators.
               -- An RF spectrum slice contains a single or multiple
               -- RF channels of the same type allocated to a given product
               -- class such as multiple voice telephony channels in a
               -- POTS product class.

               -- This table can be used to create, delete or modify
               -- a uni-directional RF spectrum slice
               -- and the related configurable parameters for a given
               -- digital product class supported in a logical
               -- HFC subnetwork. In order to create, delete or modify
               -- an RF spectrum slice, this table uses the RF channel
               -- configuration information associated with a given digital
               -- product class provided in the productClassTable to=
 determine
               -- the configuration parameter consistency and the
               -- allowed ranges of RF channel configuration parameters.

               -- This table can be used to configure an RF spectrum
               -- slice containing a single RF channel (i.e., a
               -- single RF carrier) or multiple RF channels (i.e.,
               -- multiple RF carriers) depending on the RF technology
               -- supported for a given digital product class.

               -- Implementation of this group is mandatory
               -- if providing RF spectrum management.



               rfSpectrumSliceConfigTable    OBJECT-TYPE
                         SYNTAX      SEQUENCE OF RfSpectrumSliceConfigEntry
                         ACCESS      not-accessible
                         STATUS       mandatory
                         DESCRIPTION
                          "This table contains configuration and state
                           information of the RF spectrum slice or RF=
 channel
                           depending on the RF technology supported for a=
 given






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                           digital product class in the logical HFC=
 subnetwork."
                         ::=3D { csmiMIBObjects 7 }

               rfSpectrumSliceConfigEntry    OBJECT-TYPE
                         SYNTAX         RfSpectrumSliceConfigEntry
                         ACCESS         not-accessible
                         STATUS         mandatory
                         DESCRIPTION
                          "An entry in the RF spectrum slice configuration
                           table. This entry is used to model a=
 uni-directional
                           RF spectrum slice containing a single or multiple
                           RF channels.  To create, delete or modify an RF
                           spectrum slice associated with a given digital
                           product class in a logical HFC subnetwork,
                           the following procedures are used:

                          RF spectrum slice establishment

                          (1)The Spectrum Management Application (SMA)=
 creates
                             an RF spectrum slice entry in the
                             rfSpectrumSliceConfigTable
                             by initially setting rfSpectrumSliceEntryStatus=
 to
                             createRequest.  The requested entry is checked
                             for consistency against the RF channel=
 parameters
                             defined in the productClassTable for a given
                             digital
                             product class.  The create request may fail for
                             the following reasons:
                             - The requested RF spectrum slice is already
                               in use.
                             - The frequency spectrum of the requested RF
                               spectrum slice overlaps with or very close
                               to an existing RF spectrum slice.
                             - The requested RF spectrum is unavailable.
                             - The requested RF spectrum slice configuration
                               is not supported by the Spectrum
                               Management Proxy Agent (SMPA).
                             Otherwise, the SMPA creates a row and reserves
                             the RF spectrum slice for a given digital=
 product
                             class on the specific logical HFC subnetwork.
                             The SMA may use the RF channel configuration
                             parameter values such as the desired modulation=

                             order, carrier frequency, and power level=
 values
                             defined in the productClassTable for a given
                             digital product.
                           (2)The SMA activates the RF spectrum slice by=
 setting
                              the rfSpectrumSliceEntrystatus to valid(1).
 If
                              this set is successful, the SMPA has reserved=
 the
                              resources to satisfy the requested RF spectrum
                              slice configuration parameters.


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                           (3)The SMA turns on the=
 rfSpectrumSliceAdminStatus
                              to up(1) enabling the RF spectrum slice
                              associated with a given digital product class
                              for use.

                          RF spectrum slice retirement

                          An RF spectrum slice is released by setting the
                          rfSpectrumSliceEntrysStatus to invalid(4), and the
                          SMPA may release all associated resources=
 associated
                          with that RF spectrum slice in the logical HFC
                          subnetwork.

                          RF spectrum slice reconfiguration

                          (1)The SMA modifies an RF spectrum slice=
 configuration
                             parameter(s) by initially setting the
                             rfSpectrumSliceAdminStatus to down(2) and then=

                             setting the configuration parameter(s) such as=
 the
                             rfSpectrumSliceUpperFrequency to the desired
                             value(s).  The configuration change request may=

                             fail for the following reasons:
                             - The requested RF spectrum slice configuration=
 is
                               not supported by the SMPA.
                             - The requested configuration change interferes
                               with an existing RF spectrum slice=
 configuration
                               (e.g., the requested upper frequency overlaps
                               with an existing RF spectrum slice or RF=
 channel
                            position). Otherwise, the SMPA makes the desired=

                            configuration changes.
                          (2)The SMA then sets the=
 rfSpectrumSliceAdminStatus to
                             up(1) enabling the modified RF spectrum slice=

                             associated with a given digital product class=
 for
                             use."
                         INDEX {rfSpectrumSliceHfcNetworkIndex,
                                rfSpectrumSliceProductClassIndex,
                                rfSpectrumSliceConfigIndex }
                         ::=3D { rfSpectrumSliceConfigTable  1}

               RfSpectrumSliceConfigEntry    ::=3D SEQUENCE  {
                         rfSpectrumSliceHfcNetworkIndex
                            INTEGER,
                         rfSpectrumSliceProductClassIndex
                            INTEGER,
                         rfSpectrumSliceConfigIndex
                            INTEGER,
                         rfSpectrumSliceOperStatus




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                            INTEGER,
                         rfSpectrumSliceAdminStatus
                            INTEGER,
                         rfSpectrumSliceLastChange
                            TimeTicks,
                         rfSpectrumSliceModulationOrder
                            INTEGER,
                         rfSpectrumSliceUpperFrequency
                            INTEGER,
                         rfSpectrumSliceLowerFrequency
                            INTEGER,
                         rfSpectrumSlicePowerLevel
                            INTEGER,
                         rfSpectrumSliceEntryStatus
                            EntryStatus
                              }

               rfSpectrumSliceHfcNetworkIndex    OBJECT-TYPE
                           SYNTAX       INTEGER (1..65535)
                           ACCESS       read-only
                           STATUS       mandatory
                           DESCRIPTION
                            "The value of this object identifies the logical
                             HFC subnetwork for which this entry contains
                             RF spectrum slice information.  The value of=
 this
                             object for a specific logical HFC subnetwork
                             has the same value as the=
 logicalHfcSubnetworkIndex
                             defined in logicalHfcSubnetworkTable for
                             the same logical HFC subnetwork."
                           ::=3D { rfSpectrumSliceConfigEntry 1}

               rfSpectrumSliceProductClassIndex    OBJECT-TYPE
                           SYNTAX       INTEGER (1..65535)
                           ACCESS       read-only
                           STATUS       mandatory
                           DESCRIPTION
                            "The value of this object identifies the product
                             class type supported in a specific logical HFC
                             subnetwork for which this entry contains
                             RF spectrum slice information.  The value of=
 this
                             object for a specific product class type has=
 the
                             same value as the productClassIndex defined in=

                             productClassTable for the same product class=
 type
                             supported in the logical HFC subnetwork."
                           ::=3D { rfSpectrumSliceConfigEntry 2}






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               rfSpectrumSliceConfigIndex    OBJECT-TYPE
                           SYNTAX       INTEGER (1..4294967295)
                           ACCESS       read-only
                           STATUS       mandatory
                           DESCRIPTION
                            "The value of this object identifies the RF
                             spectrum slice used for the digital product=
 class
                             supported in the logical HFC subnetwork.
                             The RF spectrum slice is configured as a uni-
                             directional slice."
                           ::=3D { rfSpectrumSliceConfigEntry 3}


               rfSpectrumSliceOperStatus    OBJECT-TYPE
                           SYNTAX     INTEGER {
                                              up(1),
                                              down(2),
                                              unknown(3)
                                               }
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the current
                             operational status of this RF spectrum slice.
                             The value up(1) indicates that the portion or=
 all
                             of the RF spectrum slice is currently=
 operational.
                             The value down(2) indicates all of the RF=
 spectrum
                             slice is not operational.  Therefore, for the
                             RF spectrum slice containing multiple
                             RF channels, the value down(2) indicates that=
 all
                             RF channels contained in the RF spectrum slice
                             are not operational and the value up(1)=
 indicates
                             that either all or at least one of the RF=
 channels
                             are operational.  The unknown state indicates
                             that the status of this RF spectrum slice=
 cannot
                             be determined."
                           ::=3D { rfSpectrumSliceConfigEntry 4}

               rfSpectrumSliceAdminStatus    OBJECT-TYPE
                           SYNTAX                INTEGER {
                                                   up(1),
                                                   down(2),
                                                   testing(3)
                                               }
                           ACCESS     read-write






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                           STATUS     mandatory
                           DESCRIPTION
                            "The value of this object indicates the
                             desired administrative status of this
                             RF spectrum slice.  The value up(1) indicates
                             that this RF spectrum slice is enabled and the
                             value down(2) indicates that it is disabled.
                             Therefore, for the RF spectrum slice containing=

                             multiple RF channels, the value down(2)=
 indicates
                             that all RF channels contained in the RF=
 spectrum
                             slice are disabled. The value up(1) indicates
                             that either all or at least one of the RF=
 channels
                             are made operational.  The value
                             testing(3) indicates that one or few of the RF=

                             channels contained in this RF spectrum slice is
                             undergoing testing."
                           DEFVAL { down }
                           ::=3D { rfSpectrumSliceConfigEntry 5}

               rfSpectrumSliceLastChange    OBJECT-TYPE
                           SYNTAX     TimeTicks
                           ACCESS     read-only
                           STATUS     mandatory
                           DESCRIPTION
                            "The value of MIB II's sysUpTime object
                             at the time this RF spectrum slice entered its
                             current operational state.  If the current
                             state was entered prior to the last
                             re-initialization of the Spectrum Management
                             Proxy Agent (SMPA), then this object contains
                             a zero value."
                           ::=3D { rfSpectrumSliceConfigEntry 6}

               rfSpectrumSliceModulationOrder    OBJECT-TYPE
                           SYNTAX         INTEGER (0..65535)
                           ACCESS     read-write
                           STATUS     mandatory
                           DESCRIPTION
                            "This object is used to configure the modulation
                             order for the RF channels in the RF spectrum=
 slice.
                             The modulation order may be the same as the
                             rfChannelDesiredModulationOrder in the
                             productClassTable.  The value of the
                             rfSpectrumSliceModulationOrder must lie between
                             the values of the rfChannelModulationMinOrder
                             and the rfChannelModulationMaxOrder defined in





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                             productClassTable for the RF channel supported=
 for
                             the same digital product class in the same=
 logical
                             HFC subnetwork.  When the agent configures the=

                             modulation order, it recomputes the RF channel
                             data rate and modifies the rfChannelDataRate
                             value in the productClassTable."
                          ::=3D { rfSpectrumSliceConfigEntry 7 }


                rfSpectrumSliceUpperFrequency    OBJECT-TYPE
                           SYNTAX         INTEGER (0..4294967295)
                           ACCESS     read-write
                           STATUS     mandatory
                           DESCRIPTION
                            "This object is used to configure the upper
                             frequency bound of the RF spectrum slice.
                             The value of the rfSpectrumSliceUpperFrequency=

                             must lie between the values of the
                             rfChannelMinFrequency and the
                             rfChannelMaxFrequency defined in=
 productClassTable
                             for the RF channel supported for the same=
 digital
                             product class in the same logical HFC=
 subnetwork.
                             The difference between the value of this object=
 and
                             the value of rfSpectrumSliceLowerFrequency must=
 be
                             equal to or greater than the value of=
 rfChannelSize
                             defined in productClassTable for the RF channel=

                             supported for the same digital product class in=
 the
                             same logical HFC subnetwork."
                           ::=3D { rfSpectrumSliceConfigEntry 8}


                rfSpectrumSliceLowerFrequency    OBJECT-TYPE
                           SYNTAX         INTEGER (0..4294967295)
                           ACCESS     read-write
                           STATUS     mandatory
                           DESCRIPTION
                            "This object is used to configure the lower
                             frequency bound of the RF spectrum slice.
                             The value of the
                             rfSpectrumSliceLowerFrequency must lie between
                             the values of the rfChannelMinFrequency and
                             the rfChannelMaxFrequency defined in
                             productClassTable for the RF channel
                             supported for the same digital product class in=
 the
                             same logical HFC subnetwork.
                             The difference between the value of this object=
 and
                             the value of rfSpectrumSliceUpperFrequency must=
 be






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                             equal to or greater than the value of=
 rfChannelSize
                             defined in productClassTable for the RF channel=

                             supported for the same digital product class in=
 the
                             same logical HFC subnetwork."
                           ::=3D { rfSpectrumSliceConfigEntry 9}


                rfSpectrumSlicePowerLevel    OBJECT-TYPE
                           SYNTAX         INTEGER
                           ACCESS     read-write
                           STATUS     mandatory
                           DESCRIPTION
                            "This object is used to configure the absolute=
 RF
                             power level of the RF channels contained within=
 the
                             RF spectrum slice.  The value is expressed
                             in units of dBmV. This object is used for=
 coarse
                             adjustment of the RF power level, and it is
                             not intended to override the finetuning of
                             the automatic power level adjustments of
                             the equipment.
                             The value of the rfSpectrumSlicePowerLevel must
                             lie between the values of the
                             rfChannelMinimumPowerLevel
                             and the rfChannelMaximumPowerLevel defined in
                             the productClassTable for the RF channel
                             type supported for the same digital product=
 class
                             in the same logical HFC subnetwork. For the
                             forward RF
                             spectrum slice, this object is used to=
 configure
                             the power level of the transmitter at the
                             Distribution Hub Equipment and for the reverse=

                             RF spectrum slice, this object is used to
                             configure the power level of the transmitter
                             at the subscriber's premises."
                           ::=3D { rfSpectrumSliceConfigEntry 10}

               rfSpectrumSliceEntryStatus   OBJECT-TYPE
                           SYNTAX     EntryStatus
                           ACCESS     read-write
                           STATUS     mandatory
                           DESCRIPTION
                            "This object is used to create, delete or
                             modify a row in this table.  To create a
                             a new RF spectrum slice, this object is=
 initially
                             set to 'createRequest'.  After completion of=
 the
                             configuration of the new entry, the spectrum
                             manager must set the appropriate instance
                             of this object to the value valid(1) or
                             aborts, setting this object to invalid(4).
                             This object must not be set to
                             'active' unless the following columnar objects



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                             exist in this row:
                             rfSpectrumSliceAdminStatus,
                             rfSpectrumSliceModulationOrder,
                             rfSpectrumSliceUpperFrequency,
                             rfSpectrumSliceLowerFrequency
                             rfSpectrumSlicePowerLevel.
                             To enable an RF spectrum slice for use, the
                             rfSpectrumSliceAdminStatus is set to 'up'.
                             To delete an existing entry in this table,
                             the manager must set the appropriate
                             instance of this object to the value=
 invalid(4).
                             Creation of an instance of this object has the
                             effect of creating the supplemental object
                             instances to complete the conceptual row.
                             An existing instance of this entry cannot
                             be created.  If circumstances occur which
                             cause an entry to become invalid, the agent
                             modifies the value of the appropriate instance=

                             of this object to invalid(4).  Whenever,
                             the value of this object for a particular
                             entry becomes invalid(4), the conceptual
                             row for that instance may be removed from
                             the table at any time, either
                             immediately or subsequently."
                            DEFVAL { valid }
                            ::=3D { rfSpectrumSliceConfigEntry 11}



























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              Common Spectrum Management Interface MIB     June 13,1996



               -- The RF Spectrum Management MIB Trap Module

               -- Enterprise-specific traps for use with the
               -- RF spectrum management.

               -- Trap definitions that follow are specified compliant with
               -- the SMI RFC1155, as amended by the extensions specified
               -- for concise MIB specifications RFC1212 and
               -- using the conventions
               -- for defining event notifications RFC1215.

               -- Implementation of these traps are mandatory
               -- if providing RF spectrum management.



               rfSpectrumChannelStatusChange   TRAP-TYPE
                        ENTERPRISE     twcable
                        VARIABLES      {rfSpectrumSliceHfcNetworkIndex,
                                        rfSpectrumSliceProductClassIndex,
                                        rfSpectrumSliceConfigIndex,
                                        rfSpectrumSliceOperStatus,
                                        rfSpectrumSliceAdminStatus }
                        DESCRIPTION
                         "An rfSpectrumChannelStatusChange trap indicates=
 the
                          change in the operational status of the RF=
 spectrum
                          channel associated with a given product class in a=

                          logical HFC subnetwork. This trap is used for=
 those RF
                          spectrum slices containing a single RF channel=
 only.
                          Therefore, this trap indicates the status of an RF=

                          channel only.  The trap may indicate an RF channel
                          failure."
                        ::=3D 1


               rfSpectrumSliceConfigTableEntryStatus   TRAP-TYPE
                        ENTERPRISE           twcable
                        VARIABLES
 {rfSpectrumSliceHfcNetworkIndex,

 rfSpectrumSliceProductClassIndex,
                                              rfSpectrumSliceConfigIndex,
                                              rfSpectrumSliceUpperFrequency,
                                              rfSpectrumSliceLowerFrequency,

 rfSpectrumSliceModulationOrder,
                                              rfSpectrumSlicePowerLevel,
                                              rfSpectrumSliceOperStatus,
                                              rfSpectrumSliceAdminStatus,
                                              rfSpectrumSliceEntryStatus





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                                                  }
                        DESCRIPTION
                         "An rfSpectrumSliceConfigTableEntryStatus trap
                          indicates that an RF spectrum slice is created,
                          deleted, or modified for a given product class
                          at this logical HFC subnetwork.  The variables
                          included in the trap identify the new, deleted,
                          or modified RF spectrum slice and the associated
                          configuration parameters for a given digital
                          service class in a logical HFC subnetwork."
                        ::=3D 2

               rfSpectrumSliceBandwidthRequest   TRAP-TYPE
                        ENTERPRISE           twcable
                        VARIABLES
 {rfSpectrumSliceHfcNetworkIndex,

 rfSpectrumSliceProductClassIndex,
                                              rfSpectrumSliceConfigIndex,
                                              rfSpectrumSliceUpperFrequency,
                                              rfSpectrumSliceLowerFrequency,

 rfSpectrumSliceModulationOrder,
                                              rfSpectrumSlicePowerLevel,
                                              rfSpectrumSliceOperStatus,
                                              rfSpectrumSliceAdminStatus,
                                              rfSpectrumSliceEntryStatus
                                                  }
                        DESCRIPTION
                         "An rfSpectrumSliceBandwidthRequest trap indicates=
 that
                          more bandwidth is needed to support the given=
 product
                          class at this logical HFC subnetwork.  The=
 variables
                          included in the trap identify the RF spectrum=
 slice
                          which needs more bandwidth. It is up to the=
 discretion
                          of the SMA to allocate more bandwidth to a given
                          product class supported in the logical
                          HFC subnetwork."
                         ::=3D 3


               rfSpectrumSliceShiftToUpperFrequency   TRAP-TYPE
                        ENTERPRISE           twcable
                        VARIABLES
 {rfSpectrumSliceHfcNetworkIndex,

 rfSpectrumSliceProductClassIndex,
                                              rfSpectrumSliceConfigIndex,
                                              rfSpectrumSliceUpperFrequency,
                                              rfSpectrumSliceLowerFrequency,

 rfSpectrumSliceModulationOrder,
                                              rfSpectrumSlicePowerLevel,
                                              rfSpectrumSliceOperStatus,
                                              rfSpectrumSliceAdminStatus,
                                              rfSpectrumSliceEntryStatus
                                                  }



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              Common Spectrum Management Interface MIB     June 13,1996



                        DESCRIPTION
                         "An rfSpectrumSliceShiftToUpperFrequency trap=
 indicates
                          that the RF spectrum slice upper frequency needs=
 to be
                          shifted to a higher frequency. This may be because=
 of
                          the performance degradation experienced by
                          existing RF spectrum slice. The variables included=
 in
                          the trap identify the RF spectrum slice whose=
 upper
                          frequency needs to be shifted.  It is up to the
                          discretion of the SMA to reconfigure the RF=
 spectrum
                          slice for a given product class supported in the
                          logical HFC subnetwork."
                         ::=3D 4

               rfSpectrumSliceShiftToLowerFrequency   TRAP-TYPE
                        ENTERPRISE           twcable
                        VARIABLES
 {rfSpectrumSliceHfcNetworkIndex,

 rfSpectrumSliceProductClassIndex,
                                              rfSpectrumSliceConfigIndex,
                                              rfSpectrumSliceUpperFrequency,
                                              rfSpectrumSliceLowerFrequency,

 rfSpectrumSliceModulationOrder,
                                              rfSpectrumSlicePowerLevel,
                                              rfSpectrumSliceOperStatus,
                                              rfSpectrumSliceAdminStatus,
                                              rfSpectrumSliceEntryStatus
                                                  }
                        DESCRIPTION
                         "An rfSpectrumSliceShiftTo=C2owerFrequency trap=
 indicates
                          that the RF spectrum slice lower frequency needs=
 to be
                          shifted to a lower frequency. This may be because=
 of
                          the performance degradation experienced by
                          existing RF spectrum slice. The variables included=
 in
                          the trap identify the RF spectrum slice whose=
 lower
                          frequency needs to be shifted.  It is up to the
                          discretion of the SMA to reconfigure the RF=
 spectrum
                          slice for a given product class supported in the
                          logical HFC subnetwork."
                         ::=3D 5






               END






          Masuma Ahmed and Mario Vecchi (editors)              [Page 67]


              Common Spectrum Management Interface MIB     June 13,1996



          11.  Acknowledgments

          This document follows Time Warner Cable's "Spectrum Management
          Agent, Request for Information", sent out to vendors last
          September 14, 1994. The final draft (v 4.00) was completed on
          June 15, 1995, and it has been available for review and comments
          leading to the current version.

          It was produced by the HFC Spectrum Management Team from
          Cablelabs, Time Warner Cable, and Time Warner Communications:

          Masuma Ahmed, Chris Barnhouse, Gregory Haberl, Jay Vaughan,
          and Mario Vecchi.

          Special thanks to Gerry White of LANCity for the review of the
          final manuscript and many valuable comments, to Tom Williams of
          CableLabs for helpful discussions on RF issues especially on RF
          modulation techniques; to David Bartlett of Time Warner
          Communications for helpful review of the early draft; and to
          Gordon Bechtel of AT&T, Bill Corley of LANCity, Ken Craft of
          Tellabs, and Hal Roberts and Rob Cooper of ADC Telecommunications
          for their valuable contributions to the RF spectrum slice envelope
          characterization.

          Special thanks to the following individuals for their valuable
          technical input in the process to define this interface,
          including comments on the earlier drafts of this document.

          ADC Telecom: Rob Cooper, Hal Roberts, Greg Machler, Greg Anderson

          Anderson Consulting: Thomas Lotocki

          Antec: Michael Pritz

          AT&T: Gordon Bechtel, Mark Klerer, Jeff Fishburn,
                Mike Kaus, Paul Bezdek

          Com21: Mark Laubach, Randy Miyazaki

          Convergence Systems Incorporated: Terry Wright

          General Instruments: Geoff Woods, Pete Cona

          Hewlett Packard (HP): Ilja Bedner

          Integrated Network Corporation: Idris Vasiz

          LANCity: Gerry White, Bill Corley




          Masuma Ahmed and Mario Vecchi (editors)              [Page 68]


              Common Spectrum Management Interface MIB     June 13,1996



          Motorola: Eva Labowicz, Larry Lloyd, Mort Stern

          Northern Telecom/Bell Northern Research: Wade Carter, Colleen=
 Reichert

          Objective Systems Integrator: Andrew Lee, Terry Poindexter

          Phillips Broadband: Al Kernes, Goyo Strkic

          Scientific Atlanta: Andrew Meyer, Scott Hardin

          Toshiba: Steve Rasmussen, Steve Hori

          Tellabs: Larry Goldman, Ken Craft

          Time Warner: Ray Buckner, Paul Gemme, Louis Williamson

          Zenith Electronics: David Lin


































          Masuma Ahmed and Mario Vecchi (editors)              [Page 69]


              Common Spectrum Management Interface MIB     June 13,1996



          12.  References

          [1]  V. Cerf,"IAB Recommendations for the Development of
               Internet Network Management Standards.  Internet Working
               Group Request for Comments 1052".  Network Information
               Center, SRI International, Menlo Park, California, April
               1988.

          [2]  V. Cerf,"Report of the Second Ad Hoc Network Management
               Review Group, Internet Working Group Request for Comments
               1052".  Network Information Center, SRI International,
               Menlo Park, California, August 1989.

          [3]  McCloghrie, K., and M. Rose, Editors, "Structure and
               Identification of Management Information for TCP/IP-based
               internets, Internet Working Group Request for Comments
               1155".  Network Information Center, SRI International,
               Menlo Park, California, May 1990.

          [4]  McCloghrie, K., and M. Rose, Editors, "Management
               Information Base for TCP/IP-based internets, Internet
               Working Group Request for Comments 1156".  Network
               Information Center, SRI International, Menlo Park,
               California, May 1990.

          [5]  J. Case, F. Fedor, M. Schoffstall, and J.  Davin,
               Editors, "Simple Network Management Protocol, Internet
               Working Group Request for Comments 1157".  Network
               Information Center, SRI International, Menlo Park,
               California, May 1990.

          [6]  McCloghrie, K., and M. Rose, Editors, "Management
               Information Base for Network Management of TCP/IP-based
               internets: MIB-II", STD 17, RFC 1213, Hughes LAN Systems,
               Performance Systems International, March 1991.

          [7]  Information Processing Systems - Open Systems
               Interconnection - Specification of Abstract Syntax
               Notation One (ASN.1), International Organization for
               Standardization.  International Standard 8824, December
               1987.

          [8]  Information Processing Systems - Open Systems
               Interconnection - Specification of Basic Encoding Rules
               for Abstract Syntax Notation One (ASN.1), International






          Masuma Ahmed and Mario Vecchi (editors)              [Page 70]


              Common Spectrum Management Interface MIB     June 13,1996



               Organization for Standardization.  International Standard
               8825, December 1987.

          [9]  McCloghrie, K., and M. Rose, Editors, "concise MIB
               Definitions, Internet Working Group Request for Comments
               1212".  Network Information Center, SRI International,
               Menlo Park, California, March 1991.

          [10] M. Rose, Editors, "A Convention for Defining Traps for
               use with SNMP, Internet Working Group Request for
               Comments 1215".  Network Information Center, SRI
               International, Menlo Park, California, March 1991.

          [11] B. Sklar, "Digital Communications Fundamentals and
               Applications". Prentice Hall, New Jersey, 1988.

          [12] Vecchi, M., and M. Fahim, "Architectural Model: The
               Spectrum Management Application (SMA) and the Common
               Spectrum Management Interface (csmi)".  White Paper, Time
               Warner Cable, May 30, 1995.

          [13] Postel, J., "Instructions to RFC Authors, Internet
               Working Group Request For Comments 1543", October 1993.





























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              Common Spectrum Management Interface MIB     June 13,1996



          13.  Security Considerations

          Security issues are not discussed in this memo.


          14.  Authors' Addresses

                            Mario P. Vecchi
                            Time Warner Cable
                            168 Inverness Drive West
                            Englewood, CO, 80112
                            Phone: (303) 799-5540
                            Fax: (303) 661-5651
                            EMail: mario.vecchi@twcable.com




                            Masuma Ahmed(*)
                            Cable Television Laboratories, Inc.
                            400 Centennial Parkway
                            Louisville, CO 80027
                            Phone: (303) 661-3782
                            Fax: (303) 661-9199
                            EMail: mxa@cablelabs.com

                            (*)new address at:
                            Terayon Corporation
                            2952 Bunker Hill Lane
                            Santa Clara, CA 95054
                            Phone: (408) 486-5207
                            EMail: mxa@terayon.com



















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              Common Spectrum Management Interface MIB     June 13,1996


          Table of Contents


          1 Status of this Memo ...................................    1
          2 Abstract ..............................................    1
          3 The Network Management Framework ......................    2
          4 Conventions ...........................................    2
          5 Objects ...............................................    2
          5.1 Format of Definitions ...............................    3
          6 RF Access Network Architecture Overview ...............    4
          7 RF Spectrum Management Architecture ...................    7
          7.1 Spectrum Management Application (SMA) ...............   12
          7.2 Spectrum Management Proxy Agent (SMPA) ..............   16
          8 RF Spectrum Terminology ...............................   16
          8.1 Forward and Reverse RF Spectrum .....................   16
          8.2 RF Modulation Techniques ............................   17
          8.3 RF Channel ..........................................   18
          8.4 RF Spectrum Slice ...................................   19
          8.4.1 RF Spectrum Slice Edge Characterization ...........   20
          8.5 Product Classes .....................................   24
          9 RF Spectrum Management MIB Overview ...................   27
          9.1 RF Spectrum Management Architecture Hierarchy .......   27
          9.2 Application of MIB II to Spectrum Management ........   28
          9.2.1 The System Group ..................................   28
          9.3 Structure of the RF Spectrum Management MIB .........   29
          10 Definitions ..........................................   34
          11 Acknowledgments ......................................   68
          12 References ...........................................   70
          13 Security Considerations ..............................   72
          14 Authors' Addresses ...................................   72





















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