Network Working Group                                           M. Ahmed
Request for Comments: 1695                                     K. Tesink
Category: Standards Track                                        Editors
                                            Bell Communications Research
                                                             August 1994


                     Definitions of Managed Objects
                     for ATM Management Version 8.0
                              using SMIv2

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Table of Contents

   1. Introduction .............................................    2
   2. The SNMPv2 Network Management Framework ..................    2
   3. Object Definitions .......................................    2
   4. ATM Terminology ..........................................    3
   4.1 VCL/VPL and VCC/VPC .....................................    3
   4.2 PVC and SVC .............................................    5
   4.3 Traffic Management Parameters ...........................    5
   4.3.1 Traffic Policing and Traffic Shaping  Parameters ......    5
   4.3.2 Cell Loss Priority ....................................    6
   4.3.3 QoS Class .............................................    6
   5. Overview .................................................    7
   5.1 Background ..............................................    7
   5.2 Structure of the MIB ....................................    7
   5.3 ATM Interface Configuration Group .......................    7
   5.4 ATM Interface DS3 PLCP and TC Layer Groups ..............    8
   5.5 ATM Virtual Link and Cross-Connect Groups ...............    8
   6. Application of MIB II to ATM .............................    8
   6.1 The System Group ........................................    8
   6.2 The Interface Group .....................................    8
   6.2.1 Support of the ATM Cell Layer by ifTable ..............    9
   7. Support of the AAL3/4 Based Interfaces ...................   10
   8. Support of the AAL5 Managed Objects ......................   10
   8.1 Managing AAL5 in a Switch ...............................   11
   8.2 Managing AAL5 in a Host .................................   12
   8.3 Support of AAL5 by ifTable ..............................   13
   8.4 Support of Proprietary Virtual Interface  by  ifT-able ..   14
   8.5 AAL5 Connection Performance Statistics Group ............   15



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   9. ILMI MIB and the ATM Managed Objects .....................   15
   10. Definitions .............................................   18
   11. Acknowledgments .........................................   72
   12. References ..............................................   72
   13. Security Considerations .................................   73
   14. Authors' Addresses ......................................   73

1.  Introduction

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in the Internet community.
   In particular, it describes objects used for managing ATM-based
   interfaces, devices, networks and services.

   This memo specifies a MIB module in a manner that is both compliant
   to the SNMPv2 SMI, and semantically identical to the peer SNMPv1
   definitions.

2.  The SNMPv2 Network Management Framework

   The SNMPv2 Network Management Framework consists of four major
   components.  They are:

      0    RFC 1442 [1] which defines the SMI, the mechanisms used
           for describing and naming objects for the purpose of
           management.

      0    STD 17, RFC 1213 [2] defines MIB-II, the core set of
           managed objects for the Internet suite of protocols.

      0    RFC 1445 [3] which defines the administrative and other
           architectural aspects of the framework.

      0    RFC 1448 [4] which defines the protocol used for network
           access to managed objects.

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

3.  Object Definitions

   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 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



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   often use a textual string, termed the descriptor, to also refer to
   the object type.

4.  ATM Terminology

   Some basic ATM terminologies are described in this section to
   facilitate defining the ATM managed objects.

4.1.  VCL/VPL and VCC/VPC

   There are two distinct types of ATM virtual connections: Virtual
   Channel Connections (VCCs) and Virtual Path Connection (VPCs).  As
   shown in Figures 1 and 2, ATM virtual connections consist of
   concatenated series of virtual links which forms a path between two
   end points, with each concatenation occurring at an ATM switch.
   Virtual links of VCCs are called Virtual Channel Links (VCLs).
   Virtual links of VPCs are called Virtual Path Links (VPLs). The VCI
   and VPI fields in the ATM cell header associate each cell of a VCC
   with a particular VCL over a given physical link.  The VPI field in
   the ATM cell header associates each cell of a VPC with a particular
   VPL over a given physical link.  Switches route cells between VCLs
   (or VPLs) via a cross-connect function according to the cells'
   VCI/VPI (or VPI) values.

            <-----------------------VCC-------------------------->
                      ------------             -----------
                      |ATM       |             |ATM       |
                      |X-Connect |             |X-Connect |
               VCL1   |Point     |    VCL2     |Point     |  VCL3
            O---------|----X-----|-------|-----|----X-----|-------O
                      |          |             |          |
                      ------------             ------------
                       ATM Switch               ATM Switch


            Figure 1: Virtual Channel Links and
                      Virtual Channel Connection














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            <-----------------------VPC-------------------------->
                      ------------             -----------
                      |ATM       |             |ATM       |
                      |X-Connect |             |X-Connect |
               VPL1   |Point     |    VPL2     |Point     |  VPL3
            O---------|----X-----|-------|-----|----X-----|-------O
                      |          |             |          |
                      ------------             ------------
                       ATM Switch               ATM Switch


            Figure 2: Virtual Path Links and
                      Virtual Path Connection

   A single ATM end-system or switch does not support the whole end-to-
   end span of a VCC (or VPC).  Rather, multiple ATM end- systems and/or
   switches each support one piece of the VCC (or VPC).   That is, each
   ATM end-system at one end of the VCC/VPC supports its end of the
   VCC/VPC  plus the VCLs or VPLs on its external interfaces, and each
   switch through which the VCC/VPC passes, supports the multiple
   VCLs/VPLs on that switch's external interfaces and the cross-
   connection of those VCLs/VPLs through that switch.  Thus, the end-
   to-end management of a VCC or VPC is achieved only by appropriate
   management of its individual pieces in combination.

   Note that for management purposes, an ATM network may be viewed as a
   large distributed switch by hiding all the network's internal
   connectivity as being internal to the distributed switch (as shown in
   Figure 2a).  This model may for example be used for Customer Network
   Management (CNM) purposes.





















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            <---------------------VCC--------------------------->
                    --------------------------------------
                    |                                    |
                    | ----------              ---------- |
                    | | ATM    |              | ATM    | |
               VCL1 | | Switch |              | Switch | | VCL3
            O-------|-|--------|------/-------|--------|-|------O
                    | |        |              |        | |
                    | ----------              ---------- |
                    |                                    |
                    |             ATM Network            |
                    --------------------------------------



            Figure 2a: ATM Network modeled as a large distributed
                       switch

   A VCC has a set of traffic characteristics (i.e., bandwidth
   parameters, QoS Class parameters, etc.).  VCLs inherit their traffic
   characteristics from the VCC of which they are a part.  VCCs are bi-
   directional by definition.  However, the traffic parameters in the
   two directions of a connection can be symmetric or asymmetric, i.e.,
   the two directions can have the same or different traffic flows.  A
   uni-directional traffic flow across a VCC is achieved by assigning a
   zero bandwidth in one direction.  Note that in addition to the
   bandwidth required by the user traffic flow, bandwidth is also
   required for OAM cell flows, even for the zero-bandwidth direction of
   a uni-directional connection.  These same principles apply to VPCs.

4.2.  PVC and SVC

   A Permanent Virtual Connection (PVC) is a provisioned VCC or VPC.  A
   Switched Virtual Connection (SVC) is a switched VCC or VPC that is
   set up in real-time via call set-up signaling procedures.  A PVC (or
   an SVC) can be a point-to-point, point-to-multipoint, or multipoint-
   to-multipoint VCC or VPC.

4.3.  Traffic Management Parameters

4.3.1.  Traffic Policing and Traffic Shaping Parameters

   In order to allocate resources fairly among different users, some
   networks police traffic at resource access points.  The traffic
   enforcement or policing taken at a UNI is called Usage Parameter
   Control (UPC) and is activated on an incoming VCL or VPL as shown in
   Figure 3.  The use of the traffic enforcer at the ingress of the
   connection is to make sure that the user traffic does not exceed the



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   negotiated traffic parameters such as the peak cell rate associated
   with a specific traffic descriptor type.


                     ----------             ----------
              UNI    |  ATM   |    NNI      |  ATM   |     UNI
               |     | switch |     |       | switch |      |
          O<---|---->X(UPC)   |<----|------>|   (UPC)X<-----|--->O
               | VCL |        |     | VCL   |        |  VCL |
                     ----------             ----------


                         Figure 3: An Example of a UPC

   In addition, traffic shaping may be performed on an outgoing VPL or
   VCL at a given ATM interface.  The function of the ATM traffic shaper
   either at the source or an egress point of the connection is to
   smooth the outgoing cell traffic inter-arrival time.  If policing or
   shaping is not performed then the policing or shaping algorithm is
   not activated.  ATM Forum has specified seven traffic descriptor
   types including one for the best effort traffic [9].

4.3.2.  Cell Loss Priority

   To prioritize traffic during resource congestion, ATM cells are
   assigned one of the two types of Cell Loss Priority (CLP), CLP=0 and
   CLP=1.  ATM cells with CLP=0 have a higher priority in regard to cell
   loss than ATM cells with CLP=1.  Therefore, during resource
   congestions, CLP=1 cells are dropped before any CLP=0 cell is
   dropped.

4.3.3.  QoS Class

   A VCC or VPC is associated with one of a number of Quality of Service
   (QoS) classes.  The following service classes have been specified:

      Service Class A: Constant bit rate video and Circuit
                       emulation
      Service Class B: Variable bit rate video/audio
      Service Class C: Connection-oriented data
      Service Class D: Connectionless data

   Four QoS classes numbered 1, 2, 3, and 4 have been specified with the
   aim of supporting service classes A, B, C, and D respectively.  The
   VCLs (or VPLs) concatenated to form a VCC (or VPC) will all have the
   same QoS class as that of the VCC (or VPC).  The Cell Loss Ratio
   (CLR), Cell Delay Variation (CDV), and end-to-end Cell Delay (CD)
   parameters are defined as part of QoS Class definition.  In addition,



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   an unspecified QoS Class numbered 0 is specified for best effort
   traffic.

5.  Overview

   ATM management objects are used to manage ATM interfaces, ATM virtual
   links,  ATM cross-connects, AAL5 entities and AAL5 connections
   supported by ATM hosts, ATM switches and ATM networks.  This section
   provides an overview and background of how to use this MIB and other
   potential MIBs for this purpose.

   The purpose of this memo is primarily to manage ATM PVCs.  ATM SVCs
   are also represented by the management information in this MIB.
   However, full management of SVCs may require additional capabilities
   which are beyond the scope of this memo.

5.1.  Background

   In addition to the MIB module defined in this memo, other MIB modules
   are necessary to manage ATM interfaces, links and cross-connects.
   Examples include MIB II for general system and interface management
   (RFC 1213 and RFC 1573), the DS3 or SONET MIBs for management of
   physical interfaces, and, as appropriate, MIB modules for
   applications that make use of ATM, such as SMDS.  These MIB modules
   are outside the scope of this specification.

   The current specification of this ATM MIB is based on SNMPv2.

5.2.  Structure of the MIB

   The managed ATM objects are arranged into the following groups:

                (1) ATM interface configuration group
                (2) ATM interface DS3 PLCP group
                (3) ATM interface TC Sublayer group
                (4) ATM interface virtual link (VPL/VCL) configuration
                    groups
                (5) ATM VP/VC cross-connect groups
                (6) AAL5 connection performance statistics group

   Note that, managed objects for activation/deactivation of OAM cell
   flows and ATM traps notifying virtual connection or virtual link
   failures are outside the scope of this memo.

5.3.  ATM Interface Configuration Group

   This group contains information on ATM cell layer configuration of
   local ATM interfaces on an ATM device in addition to the information



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   on such interfaces contained in the ifTable.

5.4.  ATM Interface DS3 PLCP and TC Layer Groups

   These groups provide performance statistics of the DS3 PLCP and TC
   sublayer of local ATM interfaces on a managed ATM device.  DS3 PLCP
   and TC sublayer are currently used to carry ATM cells respectively
   over DS3 and SONET transmission paths.

5.5.  ATM Virtual Link and Cross-Connect Groups

   ATM virtual link and cross-connect groups model bi-directional ATM
   virtual links and ATM cross-connects.  The ATM VP/VC link groups are
   implemented in an ATM host, ATM switch and ATM network.  The ATM
   switch and ATM network also implement the ATM VP/VC cross-connect
   groups.  Both link and cross-connect groups are implemented in a
   carrier's network for Customer Network Management (CNM) purposes.

   The ATM virtual link groups are used to create, delete or modify ATM
   virtual links in an ATM host, ATM switch and ATM network.  ATM
   virtual link groups along with the cross-connect groups are used to
   create, delete or modify ATM cross-connects in an ATM switch or ATM
   network (e.g., for CNM purposes).

6.  Application of MIB II to ATM

6.1.  The System Group

   For the purposes of the sysServices object in the System Group of MIB
   II [2], ATM is a data link layer protocol.  Thus, for ATM switches
   and ATM networks, sysServices will have the value "2".

6.2.  The Interface Group

   The Interfaces Group of MIB II defines generic managed objects for
   managing interfaces.  This memo contains the media-specific
   extensions to the Interfaces Group for managing ATM interfaces.

   This memo assumes the interpretation of the Interfaces Group to be in
   accordance with [5] which states that the interfaces table (ifTable)
   contains information on the managed resource's interfaces and that
   each sub-layer below the internetwork layer of a network interface is
   considered an interface.  Thus, the ATM cell layer interface is
   represented as an entry in the ifTable.  This entry is concerned with
   the ATM cell layer as a whole, and not with individual virtual
   connections which are managed via the ATM-specific managed objects
   specified in this memo.  The inter-relation of entries in the ifTable
   is defined by Interfaces Stack Group defined in [5].



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6.2.1.  Support of the ATM Cell Layer by ifTable

   Some specific interpretations of ifTable for the ATM cell layer
   follow.

          Object     Use for the generic ATM layer
          ======     =============================

          ifIndex    Each ATM port is represented by an ifEntry.

          ifDescr    Description of the ATM interface.

          ifType     The value that is allocated for ATM is 37.

          ifSpeed    The total bandwidth in bits per second
                     for use by the ATM layer.

          ifPhysAddress  The interface's address at the ATM protocol
                     sublayer; the ATM address which would be used
                     as the value of the Called Party Address
                     Information Element (IE) of a signalling
                     message for a connection which either:
                     - would terminate at this interface, or
                     - for which the Called Party Address IE
                       would need to be replaced by the Called
                       Party SubAddress IE before the message
                       was forwarded to any other interface.
                     For an interface on which signalling is
                     not supported, then the interface does not
                     necessarily have an address, but if it
                     does, then ifPhysAddress is the address which
                     would be used as above in the event that
                     signalling were supported.  If the interface
                     has multiple such addresses, then ifPhysAddress
                     is its primary address. If the interface has
                     no addresses, then ifPhysAddress is an octet
                     string of zero length.  Address encoding is as
                     per [9].  Note that addresses assigned for
                     purposes other than those listed above (e.g.,
                     an address associated with the service provider
                     side of a public network UNI) may be represented
                     through atmInterfaceAdminAddress.

          ifAdminStatus  See [5].

          ifOperStatus   Assumes the value down(2) if the ATM cell
                     layer or any layer below that layer is down.




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          ifLastChange   See [5].

          ifInOctets     The number of received octets over the
                     interface, i.e., the number of received,
                     assigned cells multiplied by 53.

          ifOutOctets    The number of transmitted octets over the
                     interface, i.e., the number of transmitted,
                     assigned cells multiplied by 53.

          ifInErrors     The number of cells dropped due to
                     uncorrectable HEC errors.

          ifInUnknownProtos The number of received cells discarded
                     during cell header validation, including
                     cells with unrecognized VPI/VCI values,
                     and cells with invalid cell header patterns.
                     If cells with undefined PTI values are discarded,
                     they are also counted here.

          ifOutErrors    See [5].

          ifName     Textual name (unique on this system) of the
                     interface or an octet string of zero length.

          ifLinkUpDownTrapEnable  Default is disabled (2).

          ifConnectorPresent      Set to false (2).

          ifPromiscuousMode       Set to false(2).

          ifHighSpeed    See [5].

          ifHCInOctets   The 64-bit version of ifInOctets; supported
                     if required by the compliance statements in [5].

          ifHCOutOctets  The 64-bit version of ifOutOctets; supported
                     if required by the compliance statements in [5].

7.  Support of the AAL3/4 Based Interfaces

   For the management of AAL3/4 CPCS layer, see [6].

8.  Support of the AAL5 Managed Objects

   Support of AAL5 managed objects in an ATM switch and ATM host are
   described below.




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8.1.  Managing AAL5 in a Switch

   Managing AAL5 in a switch involves:

      (1) performance management of an AAL5 entity as
          an internal resource in a switch

      (2) performance management of AAL5 per virtual connection

   AAL5 in a switch is modeled as shown in Figures 4 and 5.  AAL5 will
   be managed in a switch for only those virtual connections that carry
   AAL5 and are terminated at the AAL5 entity in the switch.  Note that,
   the virtual channels within the ATM UNIs carrying AAL5 will be
   switched by the ATM switching fabric (termed as ATM Entity in the
   figure) to the virtual channels on a proprietary internal interface
   associated with the AAL5 process (termed as AAL5 Entity in the
   figure). Therefore, performance management of the AAL5 resource in
   the switch will be modeled using the ifTable through an internal
   (pseudo-ATM) virtual interface and the AAL5 performance management
   per virtual connection will be supported using an additional AAL5
   connection table in the ATM MIB.  The association between the AAL5
   virtual link at the proprietary virtual, internal interface and the
   ATM virtual link at the ATM interface will be derived from the
   virtual channel cross-connect table and the virtual channel link
   table in the ATM MIB.

                        ___________________________
                        |                         |
                        |     =============       |
                        |     |    AAL5   |       |
                        |     |   Entity  |       |
                        |     =============       |
                        |           |             |
                        |         -----Prop. Virtual Interface
                        |           |             |
                        |     =============       |
                        |     |   ATM     |       |
                        |     |  Entity   |       |
                        |     =============       |
                        |_____|__|__|__|__|_______|
                              |  |  |  |  |
                             ---------------- ATM UNIs
                              |  |  |  |  |
                              |  |  |  |  |
                              v  v  v  v  v

                Figure 4 : Model of an AAL5 Entity in a Switch




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                            __________________
                            |                |
                            |   AAL5         |
                            |________________|
                            |                |
                            | Prop. Virtual  |
                            |  Interface     |
                            |________________|

               Figure 5 : AAL5 Entity's Interface Stack in a Switch

8.2.  Managing AAL5 in a Host

   Managing AAL5 in a host involves managing the AAL5 sublayer interface
   as shown in Figures 6 and 7.  The AAL5 sublayer is stacked directly
   over the ATM sublayer.  The ifTable is applied to the AAL5 sublayer
   as defined in Section 8.3.

                        ___________________________
                        |                         |
                        |     =============       |
                        |     |    AAL5   |       |
                        |     |   Entity  |       |
                        |     =============       |
                        |     |   ATM     |       |
                        |     |  Entity   |       |
                        |     =============       |
                        |___________|_____________|
                                    |
                                  __|__ ATM UNI
                                    |
                                    |
                                    v

                Figure 6 : Model of an AAL5 Entity in a Host


                            __________________
                            |                |
                            |   AAL5         |
                            |________________|
                            |                |
                            |   ATM Layer    |
                            |________________|
                            |                |
                            |  Physical Layer|
                            |________________|




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                 Figure 7 : AAL5 Entity's Interface Stack in a Host

8.3.  Support of AAL5 by ifTable

   The AAL5 entity in an ATM device (e.g., switch or host) is managed
   using the ifTable.  There are additional counters specified for AAL5
   than those specified in the ATM B-ICI document [10].  Specific
   interpretations of ifTable for the AAL5 CPCS layer are as follows.

          Object   Use for AAL5 CPCS layer entity
          ======   ==============================

          ifIndex  Each AAL5 entity is represented by an ifEntry.

          ifDescr  Description of the AAL5 entity.

          ifType   The value that is allocated for AAL5 is 49.

          ifMtu    Set to the largest PDU size for the
                   AAL5 CPCS layer that can be processed
                   by the AAL5 entity.

          ifSpeed  Set to 0.

          ifPhysAddress   An octet string of zero length.

          ifAdminStatus   See [5].

          ifOperStatus    Assumes the value down(2) if the AAL5 or
                   any layer below that layer is down.

          ifLastChange    See [5].

          ifInOctets      The number of received AAL5 CPCS PDU octets.

          ifOutOctets     The number of AAL5 CPCS PDU octets
                   transmitted.

          ifInUcastPkts   The number of received AAL5 CPCS PDUs passed
                   to a higher-layer.

          ifOutUcastPkts  The number of AAL5 CPCS PDUs received from a
                   higher-layer for transmission.
                   [Note:  The number of AAL5 PDUs actually
                   transmitted is the number received from a
                   higher-layer for transmission minus any which
                   are counted by ifOutErrors and ifOutDiscards.]




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          ifInErrors      Number of errored AAL5 CPCS PDUs received.
                   The types of errors counted include  CRC-32 errors,
                   SAR time-out errors, and oversized SDU errors.

          ifInUnknownProtos Set to 0.

          ifInDiscards    Number of received AAL5 CPCS PDUs discarded.
                   Possible reason may be input buffer overflow.

          ifOutErrors     Number of AAL5 CPCS PDUs that could not
                   be transmitted due to errors.

          ifOutDiscards   Number of AAL5 CPCS PDUs received for
                   transmission that are discarded.
                   Possible reason may be output buffer
                   overflow.

          ifInMulticastPkts  Set to 0.

          ifInBroadcastPkts  Set to 0.

          ifOutMulticastPkts Set to 0.

          ifOutBroadcastPkts Set to 0.

          ifName   Textual name (unique on this system) of the
                   AAL5 entity or an octet string of zero length.

          ifHighSpeed       Set to 0.

          ifConnectorPresent Set to false (2).

          ifPromiscuousMode Set to false(2).

          ifLinkUpDownTrapEnable     Default is disabled (2).

8.4.  Support of Proprietary Virtual Interface by ifTable

   Specific interpretations of ifTable for the proprietary virtual,
   internal interface associated with an AAL5 entity in an ATM switch
   are as follows.

          Object   Use for proprietary virtual, internal interface
                   associated with AAL entities
          ======   ===============================================

          ifIndex  Each proprietary virtual, internal interface
                   associated with AAL entities is represented by an



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                   ifEntry.

          ifDescr  Description of the proprietary virtual, internal
                   interface associated with AAL entities.

          ifType   The value that is allocated for proprietary
                   virtual, internal interface is 53.

          ifSpeed  See [5].  Set to 0 if the speed is not
                   known.

          ifPhysAddress   See [5]. An octet string of zero length
                   if no address is used for this interface.

          ifAdminStatus   See [5].

          ifOperStatus    See [5].

          ifLastChange    See [5].

          ifName   Textual name (unique on this system) of the
                   interface or an octet string of zero length.

          ifHighSpeed     See [5]. Set to 0 if the speed is not known.

          ifConnectorPresent  Set to false (2).

          ifLinkUpDownTrapEnable     Default is disabled (2).

8.5.  AAL5 Connection Performance Statistics Group

   An AAL5 connection table is used to provide AAL5 performance
   information for each AAL5 virtual connection that is terminated at
   the AAL5 entity contained within an ATM switch or host.

9.  ILMI MIB and the ATM Managed Objects

   The ILMI MIB is specified by the ATM Forum in UNI specification [9],
   to manage local ATM UNIs.  The support of the ATM management
   functions by the ILMI MIB and those contained in this memo are
   compared in Table 1.  In this table, "yes" in the "ILMI MIB"  column
   indicates that the management functions are supported by the ILMI
   MIB.  The MIB groups in the "This memo" column are the groups listed
   in Section 5.2.

   For that subset of management information which the ILMI MIB and this
   memo have in common, every effort has been made to retain identical
   semantics and syntax, even though the MIB objects are identified



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   using different OBJECT IDENTIFIERs.

                       Table 1 - Structuring of ATM Managed Objects

          ______________________________________________________________
                        |                                 |This   |ILMI|
          ATM Mgmt.Inf. |ATM Managed Objects              |memo   |MIB |
          ______________|_________________________________|_______|____|

          Local Interface Information:
          _____________________________________________________________
          ATM interface:| (1) port identifier             |ATM MIB|    |
          physical layer| (2) physical transmission types |  gr.1*|yes*|
          configuration | (3) operational status          |MIB II |    |
                        | (4) administrative status       |       |    |
                        | (5) last change status          |       |    |
          _____________________________________________________________
          ATM interface:| (1) active VPI/VCI fields       |ATM MIB|    |
          cell layer    | (2) maximum number of VPCs/VCCs |  gr.1 |yes |
          configuration | (3) configured VPCs/VCCs        |       | ** |
                        | (4) ILMI VPI/VCI values         |       |    |
                        | (5) ATM address type            |       |    |
                        | (6) ATM administrative address  |       |    |
          _____________________________________________________________
          ATM interface:|(1) received/transmitted cells   |       |    |
          cell layer    |(2) cells with HEC error         |MIB II |yes |
          performance   |(3) cell header validation errors|       |    |
          _____________________________________________________________
          ATM interface:|(1)DS3 PLCP severely errored     |ATM MIB|    |
          PLCP & TC     |   framing seconds               | gr.2,3|    |
          layer         |(2)DS3 PLCP unavailable seconds  |       |no  |
          performance   |(3)DS3 PLCP alarm state          |       |    |
                        |(4)out of cell delineation events|       |    |
                        |(5)TC alarm state                |       |    |
          _____________________________________________________________
          VP/VC link:   |(1)VPI or VPI/VCI value          |ATM MIB|    |
          configuration |(2)VCL or VPL operational status |  gr. 4|yes |
                        |(3)VCL/VPL administrative status |       |*** |
                        |(4)VCL/VPL last change status    |       |    |
                        |(5)transmit/receive traffic/QoS  |       |    |
                        |   parameters                    |       |    |
                        |(6)AAL type                      |       |    |
                        |(7)transmit/receive AAL5 SDU size|       |    |
                        |(8)AAL5 encapsulation type       |       |    |
          _____________________________________________________________






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          _____________________________________________________________
          VP/VC         |(1)cross-connect identifier      |       |    |
          Cross-connect:|(2)port identifier of one        |       |    |
          configuration |   end                           |       |    |
                        |(3)port identifier of the other  |ATM MIB|    |
                        |   end                           |  gr. 5|no  |
                        |(4)VPI or VPI/VCI value          |       |    |
                        |   of one end                    |       |    |
                        |(5)VPI or VPI/VCI value of       |       |    |
                        |   the other end                 |       |    |
                        |(6)VC/VP cross-connect           |       |    |
                        |   operational status            |       |    |
                        |(7)VC/VP cross-connect           |       |    |
                        |   administrative status         |       |    |
                        |(8)VC/VP last change status      |       |    |
          _____________________________________________________________
          VCC AAL5 CPCS |(1)PDUs discarded for CRC errors |ATM MIB|    |
          layer:        |(2)PDUs discarded due to         |  gr.6 |    |
          performance   |   reassembly time out           |       |no  |
                        |(3)PDUs discarded due to large   |       |    |
                        |   SDUs                          |       |    |
          _____________________________________________________________
          AAL5 entity:  |(1)received/transmitted PDUs     |       |    |
                        |(2)PDUs discarded due to         |       |    |
                        |   protocol errors               |MIB II |no  |
                        |(3)a set of configuration/state  |       |    |
                        |   parameters                    |       |    |
          _____________________________________________________________

          *The operational, administrative, and last change status of
          the ATM interface and the physical transmission type shall be
          supported by the interface table in MIB II (RFC 1213, RFC
          1573).  ILMI does not contain the administrative and last
          change status of the ATM interface.

          ** The ILMI MIB does not contain information on the ATM
          address type and the ATM administrative address assigned at
          the ATM interface.

          ***The ILMI MIB contains local and end-to-end operational
          status of the VPC/VCC segment.  However, it does not contain
          the VPC/VCC administrative and last change status and the VCC
          AAL information.








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10.  Definitions

               ATM-MIB DEFINITIONS ::= BEGIN

               IMPORTS
                  MODULE-IDENTITY, OBJECT-TYPE, OBJECT-IDENTITY,
                  Counter32, Integer32, IpAddress
                      FROM SNMPv2-SMI
                  TEXTUAL-CONVENTION, DisplayString,
                  TimeStamp, RowStatus
                      FROM SNMPv2-TC
                  MODULE-COMPLIANCE, OBJECT-GROUP
                      FROM SNMPv2-CONF
                  ifIndex, mib-2
                      FROM RFC1213-MIB;


               atmMIB MODULE-IDENTITY
                    LAST-UPDATED "9406072245Z"
                    ORGANIZATION "IETF AToM MIB Working Group"
                    CONTACT-INFO
                     "          Masuma Ahmed
                        Postal:  Bellcore
                                 331 Newman Springs Road
                                 Red Bank, NJ 07701
                                 US
                        Tel:     +1 908 758 2515
                        Fax:     +1 908 758 4131
                        E-mail:  mxa@mail.bellcore.com

                                 Kaj Tesink
                        Postal:  Bellcore
                                 331 Newman Springs Road
                                 Red Bank, NJ 07701
                                 US
                        Tel:     +1 908 758 5254
                        Fax:     +1 908 758 4196
                        E-mail:  kaj@cc.bellcore.com"
                    DESCRIPTION
                     "This is the MIB Module for ATM and AAL5-related
                      objects for managing ATM interfaces, ATM virtual
                      links, ATM cross-connects, AAL5 entities, and
                      and AAL5 connections."
                    ::= { mib-2 37 }

               atmMIBObjects  OBJECT IDENTIFIER ::= {atmMIB 1}

               -- This ATM MIB Module consists of the following groups:



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               -- (1) ATM Interface configuration group
               -- (2) ATM Interface DS3 PLCP group
               -- (3) ATM Interface TC Sublayer group
               -- (4) ATM Interface VPL configuration group
               -- (5) ATM Interface VCL configuration group
               -- (6) ATM VP Cross Connect group
               -- (7) ATM VC Cross Connect group
               -- (8) ATM Interface AAL5 VCC performance statistics
               --     group


               IfIndex ::= TEXTUAL-CONVENTION
                    STATUS     current
                    DESCRIPTION
                      "The value of this object identifies the interface
                       for which the entry contains management
                       information. The value of this object for a
                       particular interface has the same value as the
                       ifIndex object, defined in RFC 1213, for the same
                       interface."
                    SYNTAX     Integer32


               AtmTrafficDescrParamIndex ::= TEXTUAL-CONVENTION
                    STATUS     current
                    DESCRIPTION
                      "The value of this object identifies the row
                       in the atmTrafficDescrParamTable."
                    SYNTAX     Integer32

               atmTrafficDescriptorTypes  OBJECT IDENTIFIER ::=
                                                    {atmMIBObjects 1}

               -- The following values are defined for use as
               -- possible values of the ATM traffic descriptor type.
               -- ATM Forum specified seven types of ATM traffic
               -- descriptors.

               atmNoTrafficDescriptor  OBJECT-IDENTITY
                    STATUS     current
                    DESCRIPTION
                      "This identifies the no ATM traffic descriptor
                       type. Parameters 1, 2, 3, 4, and 5 are not used.
                       This traffic descriptor type can be used for
                       best effort traffic."
                    ::= { atmTrafficDescriptorTypes 1}

               atmNoClpNoScr  OBJECT-IDENTITY



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                    STATUS     current
                    DESCRIPTION
                     "This traffic descriptor is for no CLP and
                      no Sustained Cell Rate.  The use of the
                      parameter vector for this type:
                      Parameter 1: CLP=0+1 peak cell rate in
                                   cells per second
                      Parameter 2: not used
                      Parameter 3: not used
                      Parameter 4: not used
                      Parameter 5: not used.
                      This traffic descriptor type can be used
                      for best effort traffic."
                  ::= { atmTrafficDescriptorTypes 2}

               atmClpNoTaggingNoScr OBJECT-IDENTITY
                    STATUS     current
                    DESCRIPTION
                     "This traffic descriptor is for no CLP without
                      tagging and no Sustained Cell Rate.  The use
                      of the parameter vector for this type:
                      Parameter 1: CLP=0+1 peak cell rate in
                                   cells per second
                      Parameter 2: CLP=0 peak cell rate in
                                   cells per second
                      Parameter 3: not used
                      Parameter 4: not used
                      Parameter 5: not used."
                    ::= { atmTrafficDescriptorTypes 3}

               atmClpTaggingNoScr OBJECT-IDENTITY
                   STATUS     current
                   DESCRIPTION
                     "This traffic descriptor is for CLP with
                      tagging and no Sustained Cell Rate.  The
                      use of the parameter vector for this type:
                      Parameter 1: CLP=0+1 peak cell rate in
                                   cells per second
                      Parameter 2: CLP=0 peak cell rate in
                                   cells per second with excess
                                   traffic tagged as CLP=1
                      Parameter 3: not used
                      Parameter 4: not used
                      Parameter 5: not used."
                   ::= { atmTrafficDescriptorTypes 4}

               atmNoClpScr OBJECT-IDENTITY
                    STATUS     current



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                    DESCRIPTION
                     "This traffic descriptor is for no CLP
                      with Sustained Cell Rate.  The
                      use of the parameter vector for this type:
                      Parameter 1: CLP=0+1 peak cell rate in
                                   cells per second
                      Parameter 2: CLP=0+1 sustained cell rate in
                                   cells per second
                      Parameter 3: CLP=0+1 maximum burst size
                                   in cells
                      Parameter 4: not used
                      Parameter 5: not used."
                   ::= { atmTrafficDescriptorTypes 5}

               atmClpNoTaggingScr OBJECT-IDENTITY
                    STATUS     current
                    DESCRIPTION
                     "This traffic descriptor is for CLP
                      with Sustained Cell Rate and no tagging.
                      The use of the parameter vector for this type:
                      Parameter 1: CLP=0+1 peak cell rate in
                                   cells per second
                      Parameter 2: CLP=0 sustained cell rate in
                                   cells per second
                      Parameter 3: CLP=0 maximum burst size in cells
                      Parameter 4: not used
                      Parameter 5: not used."
                   ::= { atmTrafficDescriptorTypes 6}

               atmClpTaggingScr OBJECT-IDENTITY
                    STATUS     current
                    DESCRIPTION
                     "This traffic descriptor is for CLP
                      with tagging and Sustained Cell Rate.
                      The use of the parameter vector for this type:
                      Parameter 1: CLP=0+1 peak cell rate in
                                   cells per second
                      Parameter 2: CLP=0 sustained cell rate in
                                   cells per second with excess
                                   traffic tagged as CLP=1
                      Parameter 3: CLP=0 maximum burst size in cells
                      Parameter 4: not used
                      Parameter 5: not used."
                    ::= { atmTrafficDescriptorTypes 7}


               --    ATM Interface Configuration Parameters Group




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               -- This group contains ATM specific
               -- configuration information associated with
               -- an ATM interface beyond those
               -- supported using the ifTable.


               atmInterfaceConfTable    OBJECT-TYPE
                    SYNTAX      SEQUENCE OF AtmInterfaceConfEntry
                    MAX-ACCESS   not-accessible
                    STATUS       current
                    DESCRIPTION
                     "This table contains ATM local interface
                      configuration parameters, one entry per ATM
                      interface port."
                    ::= { atmMIBObjects 2 }

               atmInterfaceConfEntry    OBJECT-TYPE
                    SYNTAX         AtmInterfaceConfEntry
                    MAX-ACCESS     not-accessible
                    STATUS         current
                    DESCRIPTION
                     "This list contains ATM interface configuration
                      parameters and state variables."
                    INDEX { ifIndex }
                    ::= { atmInterfaceConfTable  1}

               AtmInterfaceConfEntry    ::= SEQUENCE  {
                    atmInterfaceMaxVpcs             INTEGER,
                    atmInterfaceMaxVccs             INTEGER,
                    atmInterfaceConfVpcs            INTEGER,
                    atmInterfaceConfVccs            INTEGER,
                    atmInterfaceMaxActiveVpiBits    INTEGER,
                    atmInterfaceMaxActiveVciBits    INTEGER,
                    atmInterfaceIlmiVpi             INTEGER,
                    atmInterfaceIlmiVci             INTEGER,
                    atmInterfaceAddressType         INTEGER,
                    atmInterfaceAdminAddress        OCTET STRING,
                    atmInterfaceMyNeighborIpAddress IpAddress,
                    atmInterfaceMyNeighborIfName    DisplayString
                         }

               atmInterfaceMaxVpcs    OBJECT-TYPE
                    SYNTAX       INTEGER  (0..4096)
                    MAX-ACCESS    read-write
                    STATUS         current
                    DESCRIPTION
                     "The maximum number of VPCs (PVCs and SVCs)
                      supported at this ATM interface.  At the ATM UNI,



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                      the maximum number of VPCs (PVCs and SVCs)
                      ranges from 0 to 256 only."
                    ::= { atmInterfaceConfEntry 1}

               atmInterfaceMaxVccs    OBJECT-TYPE
                    SYNTAX       INTEGER  (0..65536)
                    MAX-ACCESS     read-write
                    STATUS         current
                    DESCRIPTION
                     "The maximum number of VCCs (PVCs and SVCs)
                      supported at this ATM interface."
                    ::= { atmInterfaceConfEntry 2}

               atmInterfaceConfVpcs    OBJECT-TYPE
                    SYNTAX       INTEGER  (0..4096)
                    MAX-ACCESS     read-only
                    STATUS         current
                    DESCRIPTION
                     "The number of VPCs (PVCs and SVCs)
                      configured for use at this ATM interface.
                      At the ATM UNI, the configured number of
                      VPCs (PVCs and SVCs) can range from
                      0 to 256 only."
                    ::= { atmInterfaceConfEntry 3}

               atmInterfaceConfVccs    OBJECT-TYPE
                    SYNTAX       INTEGER  (0..65536)
                    MAX-ACCESS    read-only
                    STATUS        current
                    DESCRIPTION
                     "The number of VCCs (PVCs and SVCs)
                      configured for use at the ATM interface."
                    ::= { atmInterfaceConfEntry 4}

               atmInterfaceMaxActiveVpiBits    OBJECT-TYPE
                    SYNTAX           INTEGER  (0..12)
                    MAX-ACCESS         read-write
                    STATUS             current
                    DESCRIPTION
                     "The  maximum number of active VPI bits
                      configured for use at the ATM interface.
                      At the ATM UNI, the maximum number of active
                      VPI bits configured for use ranges from
                      0 to 8 only."
                    ::= { atmInterfaceConfEntry 5}

               atmInterfaceMaxActiveVciBits    OBJECT-TYPE
                    SYNTAX             INTEGER  (0..16)



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                    MAX-ACCESS         read-write
                    STATUS             current
                    DESCRIPTION
                     "The maximum number of active VCI bits
                      configured for use at this ATM interface."
                    ::= { atmInterfaceConfEntry 6}

               atmInterfaceIlmiVpi         OBJECT-TYPE
                    SYNTAX          INTEGER (0..255)
                    MAX-ACCESS       read-write
                    STATUS           current
                    DESCRIPTION
                     "The VPI value of the VCC supporting
                      the ILMI at this ATM interface.  If the values of
                      atmInterfaceIlmiVpi and atmInterfaceIlmiVci are
                      both equal to zero then the ILMI is not
                      supported at this ATM interface."
                    DEFVAL { 0 }
                    ::= { atmInterfaceConfEntry 7}

               atmInterfaceIlmiVci         OBJECT-TYPE
                    SYNTAX          INTEGER (0..65535)
                    MAX-ACCESS       read-write
                    STATUS           current
                    DESCRIPTION
                     "The VCI value of the VCC supporting
                      the ILMI at this ATM interface.  If the values of
                      atmInterfaceIlmiVpi and atmInterfaceIlmiVci are
                      both equal to zero then the ILMI is not
                      supported at this ATM interface."
                    DEFVAL { 16 }
                    ::= { atmInterfaceConfEntry 8}

               atmInterfaceAddressType    OBJECT-TYPE
                    SYNTAX      INTEGER {
                                         private(1),
                                         nsapE164(2),
                                         nativeE164(3),
                                         other(4)
                                        }
                    MAX-ACCESS    read-only
                    STATUS        current
                    DESCRIPTION
                     "The type of primary ATM address configured
                      for use at this ATM interface."
                    ::= { atmInterfaceConfEntry 9 }

               atmInterfaceAdminAddress    OBJECT-TYPE



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                    SYNTAX      OCTET STRING (SIZE(0..255))
                    MAX-ACCESS    read-only
                    STATUS        current
                    DESCRIPTION
                     "An address assigned for administrative purposes,
                      for example, an address associated with the
                      service provider side of a public network UNI.
                      If this interface has no assigned administrative
                      address, or when the address used for
                      administrative  purposes is the same as that used
                      for ifPhysAddress, then this is an octet string of
                      zero length."
                    ::= { atmInterfaceConfEntry 10 }

               atmInterfaceMyNeighborIpAddress OBJECT-TYPE
                    SYNTAX       IpAddress
                    MAX-ACCESS   read-write
                    STATUS       current
                    DESCRIPTION
                     "The IP address of the neighbor system connected to
                      the  far end of this interface, to which a Network
                      Management Station can send SNMP messages, as IP
                      datagrams sent to UDP port 161, in order to access
                      network management information concerning the
                      operation of that system.  Note that the value
                      of this object may be obtained in different ways,
                      e.g., by manual configuration, or through ILMI
                      interaction with the neighbor system."
                    ::= { atmInterfaceConfEntry 11 }

               atmInterfaceMyNeighborIfName    OBJECT-TYPE
                    SYNTAX       DisplayString
                    MAX-ACCESS   read-write
                    STATUS       current
                    DESCRIPTION
                     "The textual name of the interface on the neighbor
                      system on the far end of this interface, and to
                      which this interface connects.  If the neighbor
                      system is manageable through SNMP and supports
                      the object ifName, the value of this object must
                      be identical with that of ifName for the ifEntry
                      of the lowest level physical interface
                      for this port.  If this interface does not have a
                      textual name, the value of this object is a zero
                      length string.  Note that the value of this object
                      may be obtained in different ways, e.g., by manual
                      configuration, or through ILMI interaction with
                      the neighbor system."



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RFC 1695                 ATM Management Objects              August 1994


                    ::= { atmInterfaceConfEntry 12 }


               -- The ATM Interface DS3 PLCP Group

               -- This group contains the DS3 PLCP configuration and
               -- state parameters of those ATM interfaces
               -- which use DS3 PLCP for carrying ATM cells over DS3.

               atmInterfaceDs3PlcpTable    OBJECT-TYPE
                    SYNTAX      SEQUENCE OF AtmInterfaceDs3PlcpEntry
                    MAX-ACCESS   not-accessible
                    STATUS       current
                    DESCRIPTION
                     "This table contains ATM interface DS3 PLCP
                      parameters and state variables, one entry per
                      ATM interface port."
                    ::= { atmMIBObjects 3}

               atmInterfaceDs3PlcpEntry    OBJECT-TYPE
                    SYNTAX       AtmInterfaceDs3PlcpEntry
                    MAX-ACCESS   not-accessible
                    STATUS       current
                    DESCRIPTION
                     "This list contains DS3 PLCP parameters and
                      state variables at the ATM interface."
                    INDEX    {ifIndex }
                    ::= { atmInterfaceDs3PlcpTable 1}

               AtmInterfaceDs3PlcpEntry    ::= SEQUENCE  {
                    atmInterfaceDs3PlcpSEFSs         Counter32,
                    atmInterfaceDs3PlcpAlarmState    INTEGER,
                    atmInterfaceDs3PlcpUASs          Counter32
                      }


               atmInterfaceDs3PlcpSEFSs    OBJECT-TYPE
                    SYNTAX       Counter32
                    MAX-ACCESS   read-only
                    STATUS       current
                    DESCRIPTION
                     "The number of DS3 PLCP Severely Errored Framing
                      Second (SEFS).  Each SEFS represents a
                      one-second interval which contains
                      one or more SEF event."
                    ::= { atmInterfaceDs3PlcpEntry 1}

               atmInterfaceDs3PlcpAlarmState    OBJECT-TYPE



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                    SYNTAX       INTEGER {
                                          noAlarm(1),
                                          receivedFarEndAlarm(2),
                                          incomingLOF(3)
                                                }
                    MAX-ACCESS     read-only
                    STATUS         current
                    DESCRIPTION
                     "This variable indicates if there is an
                      alarm present for the DS3 PLCP.  The value
                      receivedFarEndAlarm means that the DS3 PLCP
                      has received an incoming Yellow
                      Signal, the value incomingLOF means that
                      the DS3 PLCP has declared a loss of frame (LOF)
                      failure condition, and the value noAlarm
                      means that there are no alarms present.
                      Transition from the failure to the no alarm state
                      occurs when no defects (e.g., LOF) are received
                      for more than 10 seconds."
                    ::= { atmInterfaceDs3PlcpEntry 2}

               atmInterfaceDs3PlcpUASs    OBJECT-TYPE
                    SYNTAX       Counter32
                    MAX-ACCESS   read-only
                    STATUS       current
                    DESCRIPTION
                     "The counter associated with the number of
                      Unavailable Seconds encountered by the PLCP."
                    ::= { atmInterfaceDs3PlcpEntry 3}


               -- The ATM Interface TC Sublayer Group

               -- This group contains TC sublayer configuration and
               -- state parameters of those ATM interfaces
               -- which use TC sublayer for carrying ATM cells over
               -- SONET or DS3.


               atmInterfaceTCTable    OBJECT-TYPE
                    SYNTAX      SEQUENCE OF AtmInterfaceTCEntry
                    MAX-ACCESS   not-accessible
                    STATUS       current
                    DESCRIPTION
                     "This table contains ATM interface TC
                      Sublayer parameters and state variables,
                      one entry per ATM interface port."
                    ::= { atmMIBObjects 4}



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               atmInterfaceTCEntry    OBJECT-TYPE
                    SYNTAX          AtmInterfaceTCEntry
                    MAX-ACCESS      not-accessible
                    STATUS          current
                    DESCRIPTION
                     "This list contains TC Sublayer parameters
                      and state variables at the ATM interface."
                    INDEX  {ifIndex }
                    ::= { atmInterfaceTCTable 1}

               AtmInterfaceTCEntry    ::= SEQUENCE  {
                    atmInterfaceOCDEvents      Counter32,
                    atmInterfaceTCAlarmState   INTEGER
                      }

               atmInterfaceOCDEvents    OBJECT-TYPE
                    SYNTAX        Counter32
                    MAX-ACCESS    read-only
                    STATUS        current
                    DESCRIPTION
                     "The number of times the Out of Cell
                      Delineation (OCD) events occur.  If seven
                      consecutive ATM cells have Header Error
                      Control (HEC) violations, an OCD event occurs.
                      A high number of OCD events may indicate a
                      problem with the TC Sublayer."
                    ::= { atmInterfaceTCEntry 1}

               atmInterfaceTCAlarmState    OBJECT-TYPE
                    SYNTAX        INTEGER {
                                           noAlarm(1),
                                           lcdFailure(2)
                                            }
                    MAX-ACCESS    read-only
                    STATUS        current
                    DESCRIPTION
                     "This variable indicates if there is an
                      alarm present for the TC Sublayer.  The value
                      lcdFailure indicates that a Loss of
                      Cell Delineation (LCD) failure state has been
                      declared for the TC Sublayer.  Transition from
                      failure to the no alarm state occurs
                      when 6 consecutive ATM cells
                      are received with valid HEC, followed by
                      about 10 seconds of acceptable working signal."
                     ::= { atmInterfaceTCEntry 2}





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RFC 1695                 ATM Management Objects              August 1994


               --  ATM Traffic Descriptor Parameter Group

               -- This group contains a set of self-consistent
               -- ATM traffic parameters including the
               -- ATM traffic QoS Class.

               -- The ATM virtual link tables (i.e., VPL and VCL tables)
               -- will use this ATM Traffic Descriptor table
               -- to assign traffic parameters and QoS Class
               -- to the receive and transmit directions of
               -- the ATM virtual links (i.e., VPLs and VCLs).
               -- The ATM VPL or VCL table will indicate a row
               -- in the atmTrafficDescrParamTable
               -- using its atmTrafficDescrParamIndex value.
               -- The management application can then compare a set of
               -- ATM traffic parameters with a single value.

               -- If no suitable row(s) in the atmTrafficDescrParamTable
               -- exists, the manager must create a new row(s) in this
               -- table. If such a row is created, agent checks the
               -- sanity of that set of ATM traffic parameter values.

               -- When creating a new row, the parameter values
               -- will be checked for self-consistency.
               -- Predefined/template rows may be supported.

               -- A row in the atmTrafficDescrParamTable is deleted
               -- by setting the atmTrafficDescrRowStatus to destroy(6).
               -- The agent will check whether this row is still in use
               -- by any entry of the atmVplTable or atmVclTable.
               -- The agent denies the request if the row is still in
               -- use.

               --  The ATM Traffic Descriptor Parameter Table


               atmTrafficDescrParamTable    OBJECT-TYPE
                    SYNTAX      SEQUENCE OF AtmTrafficDescrParamEntry
                    MAX-ACCESS   not-accessible
                    STATUS       current
                    DESCRIPTION
                     "This table contains information on ATM traffic
                      descriptor type and the associated parameters."
                    ::= { atmMIBObjects 5}

               atmTrafficDescrParamEntry    OBJECT-TYPE
                    SYNTAX           AtmTrafficDescrParamEntry
                    MAX-ACCESS       not-accessible



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                    STATUS           current
                    DESCRIPTION
                     "This list contains ATM traffic descriptor
                      type and the associated parameters."
                    INDEX  {atmTrafficDescrParamIndex}
                    ::= { atmTrafficDescrParamTable  1}

               AtmTrafficDescrParamEntry    ::= SEQUENCE  {
                 atmTrafficDescrParamIndex   AtmTrafficDescrParamIndex,
                 atmTrafficDescrType         OBJECT IDENTIFIER,
                 atmTrafficDescrParam1       Integer32,
                 atmTrafficDescrParam2       Integer32,
                 atmTrafficDescrParam3       Integer32,
                 atmTrafficDescrParam4       Integer32,
                 atmTrafficDescrParam5       Integer32,
                 atmTrafficQoSClass          INTEGER,
                 atmTrafficDescrRowStatus    RowStatus
                              }

               atmTrafficDescrParamIndex    OBJECT-TYPE
                    SYNTAX           AtmTrafficDescrParamIndex
                    MAX-ACCESS       not-accessible
                    STATUS        current
                    DESCRIPTION
                     "This object is used by the virtual link
                      table (i.e., VPL or VCL table)
                      to identify the row of this table."
                    ::= { atmTrafficDescrParamEntry  1}

               atmTrafficDescrType    OBJECT-TYPE
                    SYNTAX             OBJECT IDENTIFIER
                    MAX-ACCESS         read-create
                    STATUS             current
                    DESCRIPTION
                     "The value of this object identifies the type
                      of ATM traffic descriptor.
                      The type may indicate no traffic descriptor or
                      traffic descriptor with one or more parameters.
                      These parameters are specified as a parameter
                      vector, in the corresponding instances of the
                      objects:
                          atmTrafficDescrParam1
                          atmTrafficDescrParam2
                          atmTrafficDescrParam3
                          atmTrafficDescrParam4
                          atmTrafficDescrParam5."
                     DEFVAL  { atmNoTrafficDescriptor }
                     ::= { atmTrafficDescrParamEntry 2}



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               atmTrafficDescrParam1    OBJECT-TYPE
                    SYNTAX             Integer32
                    MAX-ACCESS          read-create
                    STATUS              current
                    DESCRIPTION
                     "The first parameter of the ATM traffic descriptor
                      used according to the value of
                      atmTrafficDescrType."
                    DEFVAL  { 0 }
                    ::= { atmTrafficDescrParamEntry 3}

               atmTrafficDescrParam2    OBJECT-TYPE
                    SYNTAX             Integer32
                    MAX-ACCESS          read-create
                    STATUS              current
                    DESCRIPTION
                     "The second parameter of the ATM traffic descriptor
                      used according to the value of
                      atmTrafficDescrType."
                    DEFVAL  { 0 }
                    ::= { atmTrafficDescrParamEntry 4}

               atmTrafficDescrParam3    OBJECT-TYPE
                    SYNTAX             Integer32
                    MAX-ACCESS          read-create
                    STATUS              current
                    DESCRIPTION
                     "The third parameter of the ATM traffic descriptor
                      used according to the value of
                      atmTrafficDescrType."
                    DEFVAL  { 0 }
                    ::= { atmTrafficDescrParamEntry 5}

               atmTrafficDescrParam4    OBJECT-TYPE
                    SYNTAX             Integer32
                    MAX-ACCESS          read-create
                    STATUS              current
                    DESCRIPTION
                     "The fourth parameter of the ATM traffic descriptor
                      used according to the value of
                      atmTrafficDescrType."
                    DEFVAL  { 0 }
                    ::= { atmTrafficDescrParamEntry 6}

               atmTrafficDescrParam5    OBJECT-TYPE
                    SYNTAX             Integer32
                    MAX-ACCESS          read-create
                    STATUS              current



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RFC 1695                 ATM Management Objects              August 1994


                    DESCRIPTION
                     "The fifth parameter of the ATM traffic descriptor
                      used according to the value of
                      atmTrafficDescrType."
                    DEFVAL  { 0 }
                    ::= { atmTrafficDescrParamEntry 7}

               atmTrafficQoSClass   OBJECT-TYPE
                    SYNTAX         INTEGER (0..255)
                    MAX-ACCESS      read-create
                    STATUS          current
                    DESCRIPTION
                     "The value of this object identifies the QoS Class.
                      Four Service classes have been
                      specified in the ATM Forum UNI Specification:
                      Service Class A: Constant bit rate video and
                                       Circuit emulation
                      Service Class B: Variable bit rate video/audio
                      Service Class C: Connection-oriented data
                      Service Class D: Connectionless data
                      Four QoS classes numbered 1, 2, 3, and 4 have
                      been specified with the aim to support service
                      classes A, B, C, and D respectively.
                      An unspecified QoS Class numbered `0' is used
                      for best effort traffic."
                    DEFVAL  { 0 }
                    ::= { atmTrafficDescrParamEntry 8}


               atmTrafficDescrRowStatus       OBJECT-TYPE
                    SYNTAX    RowStatus
                    MAX-ACCESS   read-create
                    STATUS          current
                    DESCRIPTION
                     "This object is used to create
                      a new row or modify or delete an
                      existing row in this table."
                    DEFVAL  { active }
                    ::= {atmTrafficDescrParamEntry 9}


               --  ATM Interface Virtual Path Link (VPL) Group

               -- This group contains configuration and state
               -- information of a bi-directional Virtual Path Link
               -- (VPL)

               -- This table can be used to create, delete or modify



Ahmed & Tesink                                                 [Page 32]


RFC 1695                 ATM Management Objects              August 1994


               -- a VPL that is terminated in an ATM host or switch.
               -- This table can also be used to create, delete or
               -- modify a VPL which is cross-connected to another
               -- VPL.

               -- In the example below, the traffic flows on the receive
               -- and transmit directions of the VPLs are characterized
               -- by atmVplReceiveTrafficDescrIndex and
               -- atmVplTransmitTrafficDescrIndex respectively.
               -- The cross-connected VPLs are identified by
               -- atmVplCrossConnectIdentifier.



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