





Network Working Group                                           T. Brown
Request for Comments: 1595                                     K. Tesink
Category: Standards Track                                        Editors
                                            Bell Communications Research
                                                              March 1994


                     Definitions of Managed Objects
                    for the SONET/SDH Interface Type

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.

Abstract

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in TCP/IP-based internets.
   In particular, it defines objects for managing Synchronous Optical
   Network/Synchronous Digital Hierarchy (SONET/SDH) objects.  This
   document is a companion document with Definitions of Managed Objects
   for the DS1/E1 and DS3/E3 Interface Types, RFC1406 [14] and RFC1407
   [13].

   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.

Table of Contents

   1. The SNMPv2 Network Management Framework ...............    2
   2. Objects ...............................................    3
   2.1 Format of Definitions ................................    3
   3. Overview ..............................................    4
   3.1 Use of the ifTable ...................................    4
   3.2 Use of ifTable for  SONET/SDH  Medium/Section/Line
       Layer ................................................    6
   3.3 Use of ifTable for SONET/SDH Paths. ..................    7
   3.4 Use of ifTable for SONET/SDH VTs/VCs .................    8
   3.5 SONET/SDH Terminology ................................    9
   3.6 Values for x for the Section, Line, Path,  and  VT
       Layers ...............................................   16
   4. Object Definitions ....................................   17
   4.1 The SONET/SDH Medium Group ...........................   18



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   4.2 The SONET/SDH Section Group ..........................   21
   4.2.1 The SONET/SDH Section Current Group ................   21
   4.2.2 The SONET/SDH Section Interval Group ...............   23
   4.3 The SONET/SDH Line Group .............................   25
   4.3.1 The SONET/SDH Line Current Group ...................   25
   4.3.2 The SONET/SDH Line Interval Group ..................   27
   4.4 The SONET/SDH Far End Line Group .....................   30
   4.4.1 The SONET/SDH Far End Line Current Group ...........   30
   4.4.2 The SONET/SDH Far End Line Interval Group ..........   32
   4.5 The SONET/SDH Path Group .............................   34
   4.5.1 The SONET/SDH Path Current Group ...................   34
   4.5.2 The SONET/SDH Path Interval Group ..................   37
   4.6 The SONET/SDH Far End Path Group .....................   39
   4.6.1 The SONET/SDH Far End Path Current Group ...........   39
   4.6.2 The SONET/SDH Far End Path Interval Group ..........   41
   4.7 The SONET/SDH Virtual Tributary Group ................   43
   4.7.1 The SONET/SDH VT Current Group .....................   43
   4.7.2 The SONET/SDH VT Interval Group ....................   46
   4.8 The SONET/SDH Far End VT Group .......................   48
   4.8.1 The SONET/SDH Far End VT Current Group .............   48
   4.8.2 The SONET/SDH Far End VT Interval Group ............   50
   4.9 Conformance Information ..............................   52
   4.10 Compliance Statements ...............................   52
   5. Acknowledgments .......................................   56
   6. References ............................................   57
   7. Security Considerations ...............................   59
   8. Authors' Addresses ....................................   59

1.  The SNMPv2 Network Management Framework

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

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

      STD 17, RFC 1213 [6] defines MIB-II, the core set of managed
      objects for the Internet suite of protocols. Reference [12]
      defines the evolution of the Interfaces Group of MIB II in terms
      of extensions and precise applications of the objects.

      RFC 1445 [4] which defines the administrative and other
      architectural aspects of the framework.

      RFC 1448 [5] which defines the protocol used for network access to
      managed objects.





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

   This specification makes also use of:

      RFC 1443 [2] which defines textual conventions for the
      specification of managed objects.

      RFC 1444 [3] which defines conformance statements for the
      specification of managed objects.

2.  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) [7]
   defined in the SMI.  In particular, each object has a name, a syntax,
   and an encoding.  The name is an object identifier, an
   administratively assigned name, which specifies an object type.  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 OBJECT
   DESCRIPTOR, to also refer to the object type.

   The syntax of an object type defines the abstract data structure
   corresponding to that object type.  The ASN.1 language is used for
   this purpose.  However, the SMI RFC 1442 purposely restricts the
   ASN.1 constructs which may be used.  These restrictions are
   explicitly made for simplicity.

   The encoding of an object type is simply how that object type is
   represented using the object type's syntax.  Implicitly tied to the
   notion of an object type's syntax and encoding is how the object type
   is represented when being transmitted on the network.  The SMI
   specifies the use of the basic encoding rules of ASN.1 [8], subject
   to the additional requirements imposed by the SNMP.

2.1.  Format of Definitions

   Section 4 contains 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 extensions
   specified in the SNMPv2 SMI.








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3.  Overview

   These objects are used when the particular media being used to
   realize an interface is a SONET/SDH interface.  At present, this
   applies to these values of the ifType variable in the Internet-
   standard MIB:

               sonet (39), sonetPath (50), sonetVT (51)

   The definitions contained herein are based on the SONET/SDH
   specifications in ANSI T1.105 and T1.106-1988 [9, 9a, 10] and CCITT
   G.707, 708, 709, and G.783 [15-18].

3.1.  Use of the ifTable

   This section specifies how the MIB II interfaces group, as defined in
   [12], is used for SONET/SDH interfaces.  The SONET/SDH layers support
   several multiplexing possibilities.

   For example in SONET, an Synchronous Transport Signal 3 (STS-3) has 3
   SONET Paths, and a STS-3c has 1 SONET Path. Another example could be
   a STS-12 having 4 SONET STS-3c Paths.  Similarly, a SONET Synchronous
   Payload Envelope (SPE) can carry many Virtual Tributaries (VTs), for
   example, one SONET SPE can carry 28 VT1.5s.  It is important to note
   that an SPE and a VT in SONET is collectively referred to as a
   Virtual Container (VC) in SDH.  Also, an STS is called Synchronous
   Transport Module (STM) in SDH.

   Not all SONET/SDH equipment terminate all SONET/SDH layers.  For
   example, an SONET/SDH STE regenerator terminates SONET/SDH Sections
   only, and is transparent for all layers above that.  SONET/SDH Add-
   Drop multiplexers and Digital Cross Connect Systems terminate
   SONET/SDH Lines. SONET/SDH Terminal Multiplexers may also terminate
   SONET/SDH Paths and VTs/VCs.

   MIB II [6], as extended by [12], accommodates these cases by
   appropriate use of the MIB II system group, and the interfaces group.
   The system group can name and describe the type of managed resource.
   The interfaces group defines which SONET/SDH layers apply, how these
   layers are configured and multiplexed.  This is achieved by proper
   representation of SONET/SDH Layers by ifEntries as defined in [12],
   as follows:









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                        _____________________________
                       |             |          |    |  >
                       |             |          |    |  |
                       |    VT 1     |..........|VT K|   > K ifEntries
                       |             |          |    |  |
                       |_____________|__________|____|  >
                       |               |      |      |  >
                       |               |      |      |  |
                       |    Path 1     |......|Path L|   > L ifEntries
                       |               |      |      |  |
                       |_______________|______|______|  >
                       |                             |  >
                       |                             |  |
                       |    Line                     |  |
                       |                             |  |
                       |_____________________________|  |
                       |                             |  |
                       |                             |  |
                       |    Section Layer            |   > 1 ifEntry
                       |                             |  |
                       |_____________________________|  |
                       |                             |  |
                       |                             |  |
                       |    Physical Medium Layer    |  |
                       |                             |  |
                       |_____________________________|  >

                       Use of ifTable for a SONET/SDH port

   The exact configuration and multiplexing of the layers is maintained
   in the ifStackTable [12].




















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3.2.  Use of ifTable for SONET/SDH Medium/Section/Line Layer

   Only the ifGeneralGroup needs to be supported.

ifTable Object    Use for combined SONET/SDH Medium/Section/Line Layer
======================================================================
           ifIndex           Interface index.

           ifDescr           SONET/SDH Medium/Section/Line

           ifType            sonet(39)

           ifSpeed           Speed of line rate for SONET/SDH,
                             (e.g., 155520000 bps).

           ifPhysAddress     The value of the Circuit Identifier.
                             If no Circuit Identifier has been assigned
                             this object should have an octet string with
                             zero length.

           ifAdminStatus     Supports read-only access.
                             The desired administrative status of the
                             interface.

           ifOperStatus      The value testing(3) is not used.
                             This object assumes the value down(2),
                             if the objects sonetSectionCurrentStatus
                             and sonetLineCurrentStatus have
                             any other value than sonetSectionNoDefect(1)
                             and sonetLineNoDefect(1), respectively.

           ifLastChange      sysUpTime at the last change in
                             ifOperStatus.

           ifName            Textual name of the interface or an
                             OCTET STRING of zero length.

           ifLinkUpDownTrapEnable   Set to enabled(1).
                                    Supports read-only access.

           ifHighSpeed       Speed of line in Mega-bits per second
                             (e.g., 155 Mbps)

           ifConnectorPresent Set to true(1).







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3.3.  Use of ifTable for SONET/SDH Paths

   Only the ifGeneralGroup needs to be supported.

          ifTable Object    Use for SONET/SDH Paths
          =========================================
           ifIndex           Interface index.

           ifDescr           SONET/SDH Path

           ifType            sonetPath(50)

           ifSpeed           set to speed of SONET/SDH path
                             (e.g., an STS-1 path has a
                             rate of 50112000 bps.)

           ifPhysAddress     Circuit Identifier or OCTET STRING of
                             zero length.

           ifAdminStatus     Supports read-only access.
                             The desired administrative status of the
                             interface.

           ifOperStatus      This object assumes the value down(2),
                             if the object sonetPathCurrentStatus has
                             any other value than sonetPathNoDefect(1).

           ifLastChange      sysUpTime at the last change in ifOperStatus.

           ifName            Textual name of the interface or an
                             OCTET STRING of zero length.

           ifLinkUpDownTrapEnable   Default value is disabled(2).
                                    Just read-only access may be
                                    supported.

           ifHighSpeed       Set to rate of SONET/SDH path
                             in Mega-bits per second.

           ifConnectorPresent Set to false(2).











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3.4.  Use of ifTable for SONET/SDH VTs/VCs

   Only the ifGeneralGroup needs to be supported.

          ifTable Object    Use for SONET/SDH VTs/VCs
          ===========================================
           ifIndex           Interface index.

           ifDescr           SONET/SDH VT/VC

           ifType            sonetVT(51)

           ifSpeed           Set to speed of VT/VC
                             (e.g., a VT1.5 has a rate of
                             1728000 bps.)

           ifPhysAddress     Circuit Identifier or OCTET STRING of
                             zero length.

           ifAdminStatus     Supports read-only access.
                             The desired administrative status of the
                             interface.

           ifOperStatus      This object assumes the value down(2),
                             if the object sonetVTCurrentStatus has
                             any other value than sonetVTNoDefect(1).

           ifLastChange      sysUpTime at the last change in
                             ifOperStatus.

           ifName            Textual name of the interface or an
                             OCTET STRING of zero length.

           ifLinkUpDownTrapEnable   Default value is disabled(2).
                                    Just read-only access may be
                                    supported.

           ifHighSpeed       Set to rate of VT in Mega-bits per second.

           ifConnectorPresent Set to false(2).











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3.5.  SONET/SDH Terminology

   The terminology used in this document to describe error conditions on
   a SONET circuit as monitored by a SONET system are from the ANSI
   T1M1.3/93-005R2 [11].  The terminology used in this document to
   describe error conditions on a SDH circuit as monitored by a SDH
   system are from the CCITT G.783 [18].  Only the SONET Performance
   Monitoring terminology is defined in this document.  The definitions
   for SDH Performance Monitoring terms are similar but not identical,
   and they can be found in [18].  If the definition in this document
   does not match the definition in the ANSI T1M1.3/93-005R2 draft
   document, the implementer should follow the definition described in
   this document.

          Section Loss Of Frame Failure (Out of Frame Event, Severely
               Errored Frame Defect)
               An Out of Frame (OOF) event (or Severely Errored Frame
               defect) is the occurrence of four contiguous errored
               frame alignment words.  A frame alignment work occupies
               the A1 and A2 bytes of an STS frame, and is defined in
               T1.105.  The SEF defect is terminated when two contiguous
               error-free frame words are detected.  Any implementation
               of the frame recovery circuitry which achieves
               realignment following an OOF within the 250 microsecond
               (two frames) interval implied by this definition is
               acceptable.

               An Loss of Frame (LOF) defect is declared when an OOF/SEF
               defect persists for a period of 3 milliseconds.  The LOF
               defect is terminated when the incoming signal remains
               continuously in-frame for a period of 1 ms to 3 ms.

               An LOF failure is declared when the LOF defect persists
               for a period of 2.5 +/- 0.5 seconds, except when an LOS
               defect or failure is present.  The LOF failure is cleared
               when the LOS failure is declared, or when the LOF defect
               is absent for 10 +/- 0.5 seconds.

          Loss of Signal
               The Loss of Signal (LOS) defect is declared when no
               transitions are detected on the incoming signal (before
               descrambling).  The LOS defect is detected  upon
               observing 2.3 to 100 microseconds of no transitions.  The
               LOS defect is cleared after a 125 microsecond interval
               (one frame) during which no LOS defect is detected.

               The LOS failure is declared when the LOS defect persists
               for a period of 2.5 +/- 0.5 seconds, or if LOS defect is



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               present when the criteria for LOF failure declaration
               have been met.  The LOS failure is cleared when the LOS
               defect is absent for a period of 10 +/- 0.5 seconds.
               Declaration of LOS failure clears any existing LOF
               failure.  Clearing the LOS failure allows immediate
               declaration of the LOF failure if conditions warrant.

          STS-Path Loss of Pointer
               An Loss of Pointer (LOP) defect is declared when either a
               valid pointer is not detected in eight consecutive
               frames, or when eight consecutive frames are detected
               with the New Data Flag (NDF) set to "1001" without a
               valid concatenation indicator (see ANSI T1.105).  A LOP
               defect is terminated when either a valid pointer with a
               normal NDF set to "0110", or a valid concatenation
               indicator is detected for three contiguous frames.
               Incoming STS-Path AIS shall not result in the declaration
               of a LOP defect.

               A STS-Path LOP failure is declared when the STS-Path LOP
               defect persists for a period of 2.5 +/- 0.5 seconds.  A
               STS-Path LOP failure is cleared when the STS-Path LOP
               defect is absent for 10 +/- 0.5 seconds.

          VT Loss of Pointer
               A VT LOP defect is declared when either a valid pointer
               is not detected in eight consecutive VT superframes, or
               when eight consecutive VT superframes are detected with
               the NDF set to "1001" without a valid concatenation
               indicator.  A VT LOP defect is terminated when either a
               valid pointer with a normal NDF set to "0110", or a valid
               concatenation indicator is detected for three contiguous
               VT superframes.  Incoming VT-Path AIS shall not result in
               declaring a VT LOP defect.

               A VT LOP failure is declared when the VT LOP defect
               persists for 2.5 +/- 0.5 seconds.  A VT LOP failure is
               cleared when the VT LOP defect is absent for 10 +/- 0.5
               seconds.

          Line Alarm Indication Signal
               A Line Alarm Indication Signal (L-AIS) is defined in ANSI
               T1.105.  The following criteria are specific to the L-AIS
               defect:

               --  Line AIS defect is detected as a "111" pattern in
               bits 6, 7, and 8 of the K2 byte in five consecutive
               frames.



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               --  Line AIS defect is terminated when bits 6, 7, and 8
               of the K2 byte do not contain the code "111" for five
               consecutive frames.

               A Line AIS failure is declared when the Line AIS defect
               persists for a period of 20.5 +/- 0.5 seconds.  A Line
               AIS failure is cleared when the Line AIS defect is absent
               for 10 +/- 0.5 seconds.

          STS-Path Alarm Indication Signal
               The STS-Path Alarm Indication Signal (AIS) is defined in
               ANSI T1.105 as all ones in bytes H1, H2, and H3 as well
               as all ones in the entire STS SPE.  The following
               criteria are specific to the STS-Path AIS defect:

               -- STS-Path AIS defect is detected as all ones in bytes
               H1 and H2 in three contiguous frames.

               -- The STS-Path AIS defect is terminated when a valid STS
               Pointer is detected with the NDF set to "1001" (inverted)
               for one frame, or  "0110" (normal) for three contiguous
               frames.

               A STS-Path AIS failure is declared when the STS-Path AIS
               defect persists for 2.5 +/- 0.5 seconds.  A STS-Path AIS
               failure is cleared when the STS-Path AIS defect is absent
               for 10 +/- 0.5 seconds.

          VT-Path Alarm Indication Signal
               The VT-Path Alarm Indication Signal (AIS) is only
               applicable for VTs in the floating mode of operation.
               VT-Path AIS is used to alert the downstream VT Path
               Terminating Entity (PTE) of an upstream failure.  Upon
               detection of a failure, Line AIS, or STS-Path AIS, an STS
               PTE will generate downstream VT-Path AIS if the STS
               Synchronous Payload Envelope (SPE) is carrying floating
               VTs.  VT-Path AIS is specified in ANSI T1.105 as all ones
               in bytes V1, V2, V3, and V4, as well as all ones in the
               entire VT SPE.  The following criteria are specific to
               VT-Path AIS defect:

               --  VT-Path AIS defect is detected by a VT PTE as all
               ones in bytes V1 and V2 in three contiguous VT
               superframes.

               --  VT-Path AIS defect is terminated when valid VT
               pointer with a valid VT size is detected with the NDF set
               to "1001" (inverted) for one VT superframe, or "0110"



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               (normal) for three contiguous VT superframes are
               detected.

               A VT-Path AIS failure is declared when the VT-Path AIS
               defect persists for 2.5 +/- 0.5 seconds.  A VT-Path AIS
               failure is cleared when the VT-Path AIS defect is absent
               for 10 +/- 0.5 seconds.

          Line Remote Defect Indication
               Line Remote Defect Indication (RDI) (aka Line FERF)
               signal is the occurrence of a "110" pattern in bit
               positions 6, 7, and 8 of the K2 byte in STS-1 #1 of the
               STS-N signal.  Line RDI is defined in ANSI T1.105.  The
               following criteria are specific to Line RDI defect:

               --  Line RDI defect is a "110" code in bits 6, 7, and 8
               of the K2 byte of in STS-1 #1 in five consecutive frames.

               --  Line RDI defect is terminated when any code other
               than "110" is detected in bits 6, 7, and 8 of the K2 byte
               in five consecutive frames.

               A Line Remote Failure Indication (RFI) failure is
               declared when the incoming Line RDI defects lasts for 2.5
               +/- 0.5 seconds.  The Line RFI failure is cleared when no
               Line RDI defects are detected for 10 +/- 0.5 seconds.

          STS-Path Remote Defect Indication
               STS-Path RDI (aka STS-Path FERF) signal shall be
               generated within 100 milliseconds by the STS PTE upon
               detection of an AIS or LOP defect.  Transmission of the
               STS-Path RDI signal shall cease within 100 milliseconds
               when the STS PTE no longer detects STS-Path AIS or STS-
               Path LOP defect.  The STS-Path RDI  shall accurately
               report the presence or absence of STS-Path AIS or STS-
               Path LOP defects.  STS-Path RDI defect is defined in ANSI
               T1.105.  The following requirements are specific to the
               STS-Path RDI defect:

               --  STS-Path RDI is detected by all STS PTEs.  STS-Path
               RDI is detected by the upstream STS PTE as a "1" in bit
               five of the Path Status byte (G1) for five contiguous
               frames.

               --  Removal of STS-Path Remote Defect Indication is
               detected by a "0" in bit 5 of the G1 byte in five
               contiguous frames.




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               A STS-Path Remote Failure Indication (RFI) failure is
               declared when the incoming STS-Path RDI defects lasts for
               2.5 +/- 0.5 seconds.  The STS-Path RFI failure is cleared
               when no STS-Path RDI defects are detected for 10 +/- 0.5
               seconds.

          VT-Path Remote Defect Indication
               VT Path RDI (aka VT Path FERF) signal shall be generated
               within 100 milliseconds by the VT PTE upon detection of a
               VT-Path AIS or LOP defect.  Transmission of the VT-Path
               RDI signal shall cease within 100 milliseconds when the
               VT PTE no longer detects VT-Path AIS or VT-Path LOP
               defect.  The VT-Path RDI  shall accurately report the
               presence or absence of VT-Path AIS or VT-Path LOP
               defects.  VT-Path RDI defect is defined in ANSI T1.105.
               The following requirements are specific to VT-Path RDI
               defect:

               --  VT-Path RDI defect is the occurrence of a "1" in bit
               4 of the VT-Path Overhead byte (V5) in five contiguous
               frames.

               --  VT-Path RDI defect is terminated when a "0" is
               detected in bit 4 of the VT-Path Overhead byte (V5) for
               five contiguous frames.

               A VT-Path Remote Failure Indication (RFI) (derived)
               failure is declared when the incoming VT-Path RDI defects
               lasts for 2.5 +/- 0.5 seconds.  The VT-Path RFI failure
               is cleared when no VT-Path RDI defects are detected for
               10 +/- 0.5 seconds.

          VT-Path Remote Failure Indication
               The VT-Path RFI signal is only required for the case of
               byte synch mapped DS1s where the DS1 frame bit is not
               mapped.  The VT-Path RFI is specified in ANSI T1.105,
               where it is currently called VT path yellow.  When
               provided, the VT-Path RFI signal is used to indicate the
               occurrence of far-end failures.  When the VT-Path RFI is
               not provided, far-end failures are derived from local
               timing of the VT-Path RDI defect.  The VT-Path RFI
               failure is declared within 5 ms of detecting the incoming
               VT-Path RFI Signal.  The VT-Path Remote Failure
               Indication (RFI) failure is cleared within 50 ms of
               detecting the removal of the incoming VT-Path RFI signal.






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          Coding Violation
               Coding Violations (CV) are Bit Interleaved Parity (BIP)
               errors that are detected in the incoming signal.  CV
               counters are incremented for each BIP error detected.
               That is, each BIP-8 can detect up to eight errors per
               STS-N frame, with each error incrementing the CV counter.
               Section CVs shall be collected using the BIP-8 in the B1
               byte located in the Section Overhead of STS-1 #1.  Line
               CVs shall be collected using the BIP-8s in B2 bytes
               located in the Line Overhead of each STS-1 (since all CVs
               on an STS-N line are counted together, this is equivalent
               to counting each error in the BIP-8*N contained in the B2
               bytes of the STS-N Line Overhead).  Thus, on an STS-N
               signal, up to 8 x N CVs may occur in each frame.  Path
               CVs shall be collected using the BIP-8 in the B3 byte of
               the STS-Path Overhead of the STS SPE.  VT CVs shall be
               collected using the BIP-2 in the V5 overhead byte of the
               floating VT.

          Errored Seconds
               At each layer, an Errored Second (ES) is a second with
               one or more Coding Violations at that layer OR one or
               more incoming defects (e.g., SEF, LOS, AIS, LOP) at that
               layer has occurred.

          Severely Errored Seconds
               At each layer, an Severely Errored Second (SES) is a
               second with x or more CVs at that layer, or a second
               during which at least one or more incoming defects at
               that layer has occurred.  Values of x vary depending on
               the line rate and the Bit Error Rate.  See Section 3.4
               for values for x.

          Severely Errored Framing Seconds
               A Severely Errored Framing Second (SEFS) is a seconds
               with containing one or more SEF events.  This counter is
               only counted at the Section Layer.

          Unavailable Seconds
               At the Line, Path, and VT layers, an unavailable second
               is calculated by counting the number of seconds that the
               interface is unavailable.  At each layer, the SONET/SDH
               interface is said to be unavailable at the onset of 10
               contiguous SESs.  The 10 SESs are included in unavailable
               time.  Once unavailable, the SONET/SDH interface becomes
               available at the onset of 10 contiguous seconds with no
               SESs.  The 10 seconds with no SESs are excluded from
               unavailable time.  With respect to the SONET/SDH error



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RFC 1595                   SONET/SDH Objects                  March 1994


               counts at each layer, all counters at that layer are
               incremented while the SONET/SDH interface is deemed
               available at that layer.  While the interface is deemed
               unavailable at that layer, the only count that is
               incremented is UASs at that layer.

               A special case exists when the 10 or more second period
               crosses the 900 second statistics window boundary, as the
               foregoing description implies that the SES and UAS
               counters must be adjusted when the Unavailable Signal
               State is entered. Clearly, successive GETs of the
               affected sonetPathIntervalSES and sonetPathIntervalUAS
               (for the Line and VT also) objects will return differing
               values if the first GET occurs during the first few
               seconds of the window.  This is viewed as an unavoidable
               side-effect of selecting the presently defined managed
               objects as a basis for this memo.

          Unequipped
               If a Path or VT connection is not provisioned (idle) the
               SONET equipment will signal this state by transmitting
               the Path or VT Signal Label as follows:
               - byte C2 of the STS Path Overhead equal to 0 for an
               unequipped Path,
               - byte V5 of the VT Path Overhead equal to 0 for an
               unequipped VT.

          Signal Label Mismatch
               A Path or VT connection is not correctly provisioned if a
               received Path or VT Signal Label mismatch occurs.  A
               received Signal Label is considered mismatched if it does
               not equal either the locally provisioned value or the
               value 'equipped non-specific' (1 hex). Note that any
               received non-zero Signal Label is considered a locally
               provisioned value of 'equipped non-specific'.  Only in-
               service, provisioned Path Terminating equipment can
               detect mismatched Signal labels. It is considered
               provisioned if it has been configured for a mapping and
               has been assigned signals to and from which the mapping
               takes place.

          Circuit Identifier
               This is a character string specified by the circuit
               vendor, and is useful when communicating with the vendor
               during the troubleshooting process.






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3.6.  Values for x for the Section, Line, Path, and VT Layers

                    Value for x for SONET/SDH Section SES Definition

               Rate            x               Minimum Bit Error Rate
               =======================================================
               OC-1             9                      1.5 x 10^-7
               0C-3            16                        1 x 10^-7
               OC-9            47                        1 x 10^-7
               OC-12           63                        1 x 10^-7
               OC-18           94                        1 x 10^-7
               OC-24          125                        1 x 10^-7
               OC-36          187                        1 x 10^-7
               OC-48          249                        1 x 10^-7


                    Value for x for SONET/SDH Line SES Definition

               Rate            x               Minimum Bit Error Rate
               =======================================================
               OC-1            12                       2 x 10^-7
               0C-3            32                       2 x 10^-7
               OC-9            94                       2 x 10^-7
               OC-12          124                       2 x 10^-7
               OC-18          186                       2 x 10^-7
               OC-24          248                       2 x 10^-7
               OC-36          370                       2 x 10^-7
               OC-48          494                       2 x 10^-7


                    Value for x for SONET/SDH STS-Path SES Definition

               Rate            x               Minimum Bit Error Rate
               =======================================================
               STS-1            9                       1.5 x 10^-7
               STS-3           16                         1 x 10^-7


                    Value for x for SONET/SDH VT-Path SES Definition

               Rate            x               Minimum Bit Error Rate
               =======================================================
               VT1.5            4                       2 x 10^-6
               VT2              6                       2 x 10^-6
               VT3              8                       2 x 10^-6
               VT6             14                       2 x 10^-6





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4.  Object Definitions

          SONET-MIB DEFINITIONS ::= BEGIN


          IMPORTS
              MODULE-IDENTITY, OBJECT-TYPE, Counter32, Gauge32,
              Integer32,
                    FROM SNMPv2-SMI
              TEXTUAL-CONVENTION, DisplayString
                    FROM SNMPv2-TC
              MODULE-COMPLIANCE, OBJECT-GROUP
                    FROM SNMPv2-CONF
              ifIndex, transmission
                    FROM RFC-1213;

          --  This is the MIB module for the SMDS Interface objects.


          sonetMIB MODULE-IDENTITY
              LAST-UPDATED "9401030000Z"
              ORGANIZATION "IETF AToM MIB Working Group"
              CONTACT-INFO
                "        Tracy Brown

                 Postal: Bell Communications Research
                         331 Newman Springs Road
                         P.O. Box 7020
                         Red Bank, NJ  07701-7020
                         US

                    Tel: +1 908 758 2107
                    Fax: +1 908 758 4177

                 E-mail: tacox@mail.bellcore.com


                         Kaj Tesink

                 Postal: Bell Communications Research
                         331 Newman Springs Road
                         P.O. Box 7020
                         Red Bank, NJ  07701-7020
                         US

                    Tel: +1 908 758 5254
                    Fax: +1 908 758 4196




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                 E-mail: kaj@cc.bellcore.com"
              DESCRIPTION
                   "The MIB module to describe
                   SONET/SDH interfaces objects."
              ::= { transmission 39 }


          --  This is the MIB module for the SONET/SDH objects

          sonetObjects      OBJECT IDENTIFIER ::= { sonetMIB 1 }

          sonetObjectsPath  OBJECT IDENTIFIER ::= { sonetMIB 2 }

          sonetObjectsVT    OBJECT IDENTIFIER ::= { sonetMIB 3 }


          -- groups in the SONET/SDH MIB module

          sonetMedium       OBJECT IDENTIFIER ::= { sonetObjects 1 }

          sonetSection      OBJECT IDENTIFIER ::= { sonetObjects 2 }

          sonetLine         OBJECT IDENTIFIER ::= { sonetObjects 3 }

          sonetFarEndLine   OBJECT IDENTIFIER ::= { sonetObjects 4 }

          sonetPath         OBJECT IDENTIFIER ::= { sonetObjectsPath 1 }

          sonetFarEndPath   OBJECT IDENTIFIER ::= { sonetObjectsPath 2 }

          sonetVT           OBJECT IDENTIFIER ::= { sonetObjectsVT 1 }

          sonetFarEndVT     OBJECT IDENTIFIER ::= { sonetObjectsVT 2 }


          -- the SONET/SDH Medium group

          -- SONET/SDH interfaces for some applications may be
          -- electrical interfaces and not optical interfaces.
          -- This group handles the configuration information for
          -- both optical SONET/SDH interfaces and electrical
          -- SONET/SDH interfaces.

          sonetMediumTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetMediumEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION



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                 "The SONET/SDH Medium table."
               ::= { sonetMedium 1 }

          sonetMediumEntry OBJECT-TYPE
              SYNTAX  SonetMediumEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                 "An entry in the SONET/SDH Medium table."
              INDEX   { ifIndex }
               ::= { sonetMediumTable 1 }

          SonetMediumEntry ::=
              SEQUENCE {
                   sonetMediumType               INTEGER,
                   sonetMediumTimeElapsed        Integer32,
                   sonetMediumValidIntervals     Integer32,
                   sonetMediumLineCoding         INTEGER,
                   sonetMediumLineType           INTEGER,
                   sonetMediumCircuitIdentifier  DisplayString
              }


          sonetMediumType OBJECT-TYPE
              SYNTAX  INTEGER  {
                         sonet(1),
                         sdh(2)
                      }
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "This variable identifies whether a SONET
                 or a SDH signal is used across this interface."
              ::= { sonetMediumEntry 1 }

          sonetMediumTimeElapsed OBJECT-TYPE
              SYNTAX  Integer32 (1..900)
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "The number of seconds, including partial
                 seconds, that have elapsed since the beginning of
                 the current error-measurement period."
              ::= { sonetMediumEntry 2 }

          sonetMediumValidIntervals OBJECT-TYPE
              SYNTAX  Integer32 (0..96)
              MAX-ACCESS  read-only



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              STATUS  current
              DESCRIPTION
                 "The number of previous intervals for which valid
                 data has been stored.  A SONET device must support
                 at least n intervals.
                 The minimum value of n is 4.
                 The default of n is 32.
                 The maximum value of n is 96.
                 The value of this object will be n unless
                 the device was brought online within the last
                 (nx15) minutes, in which case the value will be the
                 number of complete 15 minute intervals the device has
                 been online."
              ::= { sonetMediumEntry 3 }

          sonetMediumLineCoding OBJECT-TYPE
              SYNTAX  INTEGER {
                          sonetMediumOther(1),
                          sonetMediumB3ZS(2),
                          sonetMediumCMI(3),
                          sonetMediumNRZ(4),
                          sonetMediumRZ(5)
                      }
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "This variable describes the line coding for
                 this interface. The B3ZS and CMI are used for
                 electrical SONET/SDH signals (STS-1 and STS-3).
                 The Non-Return to Zero (NRZ) and the Return
                 to Zero are used for optical SONET/SDH signals."
              ::= { sonetMediumEntry 4 }

          sonetMediumLineType OBJECT-TYPE
              SYNTAX  INTEGER {
                          sonetOther(1),
                          sonetShortSingleMode(2),
                          sonetLongSingleMode(3),
                          sonetMultiMode(4),
                          sonetCoax(5),
                          sonetUTP(6)
                      }
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "This variable describes the line type for
                 this interface. The line types are
                 Short and Long Range



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                 Single Mode fiber or Multi-Mode fiber interfaces,
                 and coax and UTP for electrical interfaces.  The
                 value sonetOther should be used when the Line Type is
                 not one of the listed values."
              ::= { sonetMediumEntry 5 }

          sonetMediumCircuitIdentifier OBJECT-TYPE
              SYNTAX  DisplayString (SIZE (0..255))
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "This variable contains the transmission
                 vendor's circuit identifier, for the
                 purpose of facilitating troubleshooting."
              ::= { sonetMediumEntry 6 }


          -- the SONET/SDH Section group

          -- this group consists of 2 tables:
          -- - the SONET/SDH Section Current Table
          -- - the SONET/SDH Section Interval Table



          -- the SONET/SDH Section Current Table

          -- The SONET/SDH Section
          -- current table contains various statistics
          -- being collected for the current 15 minute interval.

          sonetSectionCurrentTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetSectionCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                 "The SONET/SDH Section Current table."
               ::= { sonetSection 1 }

          sonetSectionCurrentEntry OBJECT-TYPE
              SYNTAX  SonetSectionCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                 "An entry in the SONET/SDH Section Current table."
              INDEX   { ifIndex }
               ::= { sonetSectionCurrentTable 1 }




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          SonetSectionCurrentEntry ::=
              SEQUENCE {
                  sonetSectionCurrentStatus   Integer32,
                  sonetSectionCurrentESs      Gauge32,
                  sonetSectionCurrentSESs     Gauge32,
                  sonetSectionCurrentSEFSs    Gauge32,
                  sonetSectionCurrentCVs      Gauge32
              }


          sonetSectionCurrentStatus OBJECT-TYPE
              SYNTAX  Integer32 (1..6)
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "This variable indicates the
                 status of the interface.
                 The sonetSectionCurrentStatus
                 is a bit map represented
                 as a sum, therefore,
                 it can represent multiple defects
                 simultaneously.
                 The sonetSectionNoDefect should be
                 set if and only if
                 no other flag is set.

                 The various bit positions are:
                       1   sonetSectionNoDefect
                       2   sonetSectionLOS
                       4   sonetSectionLOF"
               ::= { sonetSectionCurrentEntry 1 }

          sonetSectionCurrentESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "The counter associated with the number of Errored
                 Seconds encountered by a SONET/SDH
                 Section in the current 15 minute interval."
               ::= { sonetSectionCurrentEntry 2 }

          sonetSectionCurrentSESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "The counter associated with the number of



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                 Severely Errored Seconds
                 encountered by a SONET/SDH Section in the current 15
                 minute interval."
               ::= { sonetSectionCurrentEntry 3 }

          sonetSectionCurrentSEFSs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "The counter associated with the number of
                 Severely Errored Framing Seconds
                 encountered by a SONET/SDH Section in the current
                 15 minute interval."
              ::= { sonetSectionCurrentEntry 4 }

          sonetSectionCurrentCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "The counter associated with the number of Coding
                 Violations encountered by a
                 SONET/SDH Section in the current 15 minute interval."
               ::= { sonetSectionCurrentEntry 5 }


          -- the SONET/SDH Section Interval Table

          -- The SONET/SDH Section Interval Table
          -- contains various statistics
          -- collected by each system over a maximum
          -- of the previous 24 hours of
          -- operation.  The past 24 hours may be broken into 96
          -- completed 15 minute intervals.
          -- A system is required to store at
          -- least 4 completed 15 minute interval.
          -- The default value is 32 intervals.

          sonetSectionIntervalTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetSectionIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                 "The SONET/SDH Section Interval table."
               ::= { sonetSection 2 }

          sonetSectionIntervalEntry OBJECT-TYPE



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              SYNTAX  SonetSectionIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                 "An entry in the SONET/SDH Section Interval table."
              INDEX   { ifIndex,
                        sonetSectionIntervalNumber }
               ::= { sonetSectionIntervalTable 1 }

          SonetSectionIntervalEntry ::=
              SEQUENCE {
                   sonetSectionIntervalNumber  Integer32,
                   sonetSectionIntervalESs     Gauge32,
                   sonetSectionIntervalSESs    Gauge32,
                   sonetSectionIntervalSEFSs   Gauge32,
                   sonetSectionIntervalCVs     Gauge32
              }


          sonetSectionIntervalNumber OBJECT-TYPE
              SYNTAX  Integer32 (1..96)
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                "A number between 1 and 96, which identifies the
                interval for which the set of statistics is available.
                The interval identified by 1 is the most recently
                completed 15 minute interval,
                and the interval identified
                by N is the interval immediately preceding the
                one identified
                by N-1."
               ::= { sonetSectionIntervalEntry 1 }

          sonetSectionIntervalESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "The counter associated with the number of
                 Errored Seconds encountered
                 by a SONET/SDH Section in a
                 particular 15-minute interval
                 in the past 24 hours."
               ::= { sonetSectionIntervalEntry 2 }

          sonetSectionIntervalSESs OBJECT-TYPE
              SYNTAX  Gauge32



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              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "The counter associated with the number of
                 Severely Errored Seconds
                 encountered by a SONET/SDH Section in a
                 particular 15-minute interval
                 in the past 24 hours."
              ::= { sonetSectionIntervalEntry 3 }

          sonetSectionIntervalSEFSs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "The counter associated with the number of
                 Severely Errored Framing Seconds
                 encountered by a SONET/SDH Section in a
                 particular 15-minute interval
                 in the past 24 hours."
              ::= { sonetSectionIntervalEntry 4 }

          sonetSectionIntervalCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "The counter associated with the number of Coding
                 Violations encountered by a
                 SONET/SDH Section in a particular 15-minute interval
                 in the past 24 hours."
              ::= { sonetSectionIntervalEntry 5 }


          -- the SONET/SDH Line group

          -- this group consists of 2 tables:
          -- - the SONET/SDH Line Current Table
          -- - the SONET/SDH Line Interval Table


          -- the SONET/SDH Line Current Table

          -- The SONET/SDH Line
          -- current table contains various statistics
          -- being collected for the current 15 minute interval.

          sonetLineCurrentTable OBJECT-TYPE



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              SYNTAX  SEQUENCE OF SonetLineCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                "The SONET/SDH Line Current table."
              ::= { sonetLine 1 }

          sonetLineCurrentEntry OBJECT-TYPE
              SYNTAX  SonetLineCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                "An entry in the SONET/SDH Line Current table."
              INDEX   { ifIndex }
              ::= { sonetLineCurrentTable 1 }

          SonetLineCurrentEntry ::=
              SEQUENCE {
                   sonetLineCurrentStatus    Integer32,
                   sonetLineCurrentESs       Gauge32,
                   sonetLineCurrentSESs      Gauge32,
                   sonetLineCurrentCVs       Gauge32,
                   sonetLineCurrentUASs      Gauge32
               }


          sonetLineCurrentStatus OBJECT-TYPE
              SYNTAX  Integer32 (1..6)
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "This variable indicates the
                 status of the interface.
                 The sonetLineCurrentStatus
                 is a bit map represented
                 as a sum, therefore,
                 it can represent multiple defects
                 simultaneously.
                 The sonetLineNoDefect should be
                 set if and only if
                 no other flag is set.

                 The various bit positions are:
                  1   sonetLineNoDefect
                  2   sonetLineAIS
                  4   sonetLineRDI"
               ::= { sonetLineCurrentEntry 1 }




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          sonetLineCurrentESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of Errored
               Seconds encountered by a SONET/SDH
               Line in the current 15 minute interval."
              ::= { sonetLineCurrentEntry 2 }

          sonetLineCurrentSESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of
               Severely Errored Seconds
               encountered by a SONET/SDH Line in the current 15
               minute
               interval."
              ::= { sonetLineCurrentEntry 3 }

          sonetLineCurrentCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of Coding
               Violations encountered by a
               SONET/SDH Line in the current 15 minute interval."
              ::= { sonetLineCurrentEntry 4 }

          sonetLineCurrentUASs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of
               Unavailable Seconds
               encountered by a SONET/SDH Line in the current 15
               minute
               interval."
              ::= { sonetLineCurrentEntry 5 }


          -- the SONET/SDH Line Interval Table

          -- The SONET/SDH Line Interval Table



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          -- contains various statistics
          -- collected by each system over a maximum
          -- of the previous 24 hours of
          -- operation.  The past 24 hours may be broken into 96
          -- completed 15 minute intervals.
          -- A system is required to store at
          -- least 4 completed 15 minute interval.
          -- The default value is 32 intervals.

          sonetLineIntervalTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetLineIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                 "The SONET/SDH Line Interval table."
               ::= { sonetLine 2 }

          sonetLineIntervalEntry OBJECT-TYPE
              SYNTAX  SonetLineIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                 "An entry in the SONET/SDH Line Interval table."
             INDEX   { ifIndex,
                       sonetLineIntervalNumber }
             ::= { sonetLineIntervalTable 1 }

          SonetLineIntervalEntry ::=
              SEQUENCE {
                  sonetLineIntervalNumber    Integer32,
                  sonetLineIntervalESs       Gauge32,
                  sonetLineIntervalSESs      Gauge32,
                  sonetLineIntervalCVs       Gauge32,
                  sonetLineIntervalUASs      Gauge32
              }


          sonetLineIntervalNumber OBJECT-TYPE
              SYNTAX  Integer32 (1..96)
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                  "A number between 1 and 96, which identifies the
                  interval for which the set of statistics is available.
                  The interval identified by 1 is the most recently
                  completed 15 minute interval,
                  and the interval identified
                  by N is the interval immediately preceding the



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                  one identified
                  by N-1."
               ::= { sonetLineIntervalEntry 1 }

          sonetLineIntervalESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "The counter associated with the number of
                 Errored Seconds encountered
                 by a SONET/SDH Line in a
                 particular 15-minute interval
                 in the past 24 hours."
               ::= { sonetLineIntervalEntry 2 }

          sonetLineIntervalSESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                 "The counter associated with the number of
                 Severely Errored Seconds
                 encountered by a SONET/SDH Line in a
                 particular 15-minute interval
                 in the past 24 hours."
                ::= { sonetLineIntervalEntry 3 }

          sonetLineIntervalCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                "The counter associated with the number of Coding
                Violations encountered by a
                SONET/SDH Line in a
                particular 15-minute interval
                in the past 24 hours."
              ::= { sonetLineIntervalEntry 4 }

          sonetLineIntervalUASs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                "The counter associated with the
                number of Unavailable Seconds
                encountered by a SONET/SDH Line in



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                a particular 15-minute interval
                in the past 24 hours."
              ::= { sonetLineIntervalEntry 5 }


          -- The SONET/SDH Far End Line group.
          -- This group may only be implemented by SONET/SDH (LTEs)
          -- systems that provide for a far end block error (FEBE)
          -- information at the SONET/SDH Line Layer.

          -- This group consists of two tables:
          --    SONET/SDH Far End Line Current Table
          --    SONET/SDH Far End Line Interval Table



          -- The SONET/SDH Far End Line Current Table

          -- The SONET/SDH Far End Line Current table contains
          -- various statistics being
          -- collected for the current 15 minute interval.
          -- The statistics are collected from the far end
          -- block error code (FEBE)
          -- within the third Z2 byte of the Line Overhead
          -- in Broadband ISDN applications.
          -- The definitions are the same as described for
          -- the near-end information.

          sonetFarEndLineCurrentTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetFarEndLineCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                "The SONET/SDH Far End Line Current table."
              ::= { sonetFarEndLine 1 }

          sonetFarEndLineCurrentEntry OBJECT-TYPE
              SYNTAX  SonetFarEndLineCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                "An entry in the SONET/SDH Far End Line Current table."
              INDEX   { ifIndex }
              ::= { sonetFarEndLineCurrentTable 1 }

          SonetFarEndLineCurrentEntry ::=
              SEQUENCE {
                  sonetFarEndLineCurrentESs       Gauge32,



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                  sonetFarEndLineCurrentSESs      Gauge32,
                  sonetFarEndLineCurrentCVs       Gauge32,
                  sonetFarEndLineCurrentUASs      Gauge32
                 }


          sonetFarEndLineCurrentESs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                 "The counter associated with the number of Far
                 Far End Errored Seconds encountered by a SONET/SDH
                 interface in the current 15 minute interval."
             ::= { sonetFarEndLineCurrentEntry 1 }

          sonetFarEndLineCurrentSESs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                 "The counter associated with the number of
                 Far End Severely Errored Seconds
                 encountered by a SONET/SDH Medium/Section/Line
                 interface in the current 15 minute
                 interval."
             ::= { sonetFarEndLineCurrentEntry 2 }

          sonetFarEndLineCurrentCVs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                 "The counter associated with the number of
                 Far End Coding Violations reported via
                 the far end block error count
                 encountered by a
                 SONET/SDH Medium/Section/Line
                 interface in the current 15 minute interval."
             ::= { sonetFarEndLineCurrentEntry 3 }

          sonetFarEndLineCurrentUASs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                 "The counter associated with the number of
                 Far End Unavailable Seconds



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RFC 1595                   SONET/SDH Objects                  March 1994


                 encountered by a
                 SONET/SDH Medium/Section/Line
                 interface in the current 15 minute interval."
             ::= { sonetFarEndLineCurrentEntry 4 }


          -- The SONET/SDH Far End Line Interval Table

          -- The SONET/SDH Far End Line Interval Table
          -- contains various statistics
          -- collected by each system over a maximum
          -- of the previous 24 hours of
          -- operation.  The past 24 hours may be broken into 96
          -- completed 15 minute intervals.
          -- A system is required to store at
          -- least 4 completed 15 minute interval.
          -- The default value is 32 intervals.

          sonetFarEndLineIntervalTable OBJECT-TYPE
             SYNTAX  SEQUENCE OF SonetFarEndLineIntervalEntry
             MAX-ACCESS  not-accessible
             STATUS  current
             DESCRIPTION
                "The SONET/SDH Far End Line Interval table."
             ::= { sonetFarEndLine 2 }

          sonetFarEndLineIntervalEntry OBJECT-TYPE
             SYNTAX  SonetFarEndLineIntervalEntry
             MAX-ACCESS  not-accessible
             STATUS  current
             DESCRIPTION
               "An entry in the SONET/SDH Far
               End Line Interval table."
             INDEX   { ifIndex,
                       sonetFarEndLineIntervalNumber }
             ::= { sonetFarEndLineIntervalTable 1 }

          SonetFarEndLineIntervalEntry ::=
              SEQUENCE {
                   sonetFarEndLineIntervalNumber    Integer32,
                   sonetFarEndLineIntervalESs       Gauge32,
                   sonetFarEndLineIntervalSESs      Gauge32,
                   sonetFarEndLineIntervalCVs       Gauge32,
                   sonetFarEndLineIntervalUASs      Gauge32
              }


          sonetFarEndLineIntervalNumber OBJECT-TYPE



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             SYNTAX  Integer32 (1..96)
             MAX-ACCESS  not-accessible
             STATUS  current
             DESCRIPTION
                   "A number between 1 and 96, which identifies the
                   interval for which the set of statistics is available.
                   The interval identified by 1 is the most recently
                   completed 15 minute interval,
                   and the interval identified
                   by N is the interval immediately preceding the
                   one identified
                   by N-1."
             ::= { sonetFarEndLineIntervalEntry 1 }

          sonetFarEndLineIntervalESs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                  "The counter associated with the number of
                  Far End Errored Seconds encountered
                  by a SONET/SDH Line
                  interface in a particular 15-minute interval
                  in the past 24 hours."
            ::= { sonetFarEndLineIntervalEntry 2 }

          sonetFarEndLineIntervalSESs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                  "The counter associated with the number of
                  Far End Severely Errored Seconds
                  encountered by a SONET/SDH Line
                  interface in a particular 15-minute interval
                  in the past 24 hours."
            ::= { sonetFarEndLineIntervalEntry 3 }

          sonetFarEndLineIntervalCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                   "The counter associated with the number of
                   Far End Coding Violations reported via
                   the far end block error count
                   encountered by a
                   SONET/SDH Line



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                   interface in a particular 15-minute interval
                   in the past 24 hours."
              ::= { sonetFarEndLineIntervalEntry 4 }

          sonetFarEndLineIntervalUASs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                 "The counter associated with the number of
                 Far End Unavailable Seconds
                 encountered by a
                 SONET/SDH Line
                 interface in a particular 15-minute interval
                 in the past 24 hours."
             ::= { sonetFarEndLineIntervalEntry 5 }


          -- the SONET/SDH Path group

          -- this group consists of 2 tables:
          -- - the SONET/SDH Path Current Table
          -- - the SONET/SDH Path Interval Table


          -- the SONET/SDH Path Current Table

          -- The SONET/SDH Path
          -- current table contains various statistics
          -- being collected for the current 15 minute interval.

          sonetPathCurrentTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetPathCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
               "The SONET/SDH Path Current table."
          ::= { sonetPath 1 }

          sonetPathCurrentEntry OBJECT-TYPE
              SYNTAX  SonetPathCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
               "An entry in the SONET/SDH Path Current table."
              INDEX   { ifIndex }
          ::= { sonetPathCurrentTable 1 }




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          SonetPathCurrentEntry ::=
              SEQUENCE {
                  sonetPathCurrentWidth      INTEGER,
                  sonetPathCurrentStatus     Integer32,
                  sonetPathCurrentESs        Gauge32,
                  sonetPathCurrentSESs       Gauge32,
                  sonetPathCurrentCVs        Gauge32,
                  sonetPathCurrentUASs       Gauge32
              }


          sonetPathCurrentWidth OBJECT-TYPE
              SYNTAX  INTEGER  {
                      sts1(1),
                      sts3cSTM1(2),
                      sts12cSTM4(3),
                      sts24c(4),
                      sts48cSTM16(5)
               }
              MAX-ACCESS  read-write
              STATUS  current
              DESCRIPTION
               "A value that indicates the type of the SONET/SDH
               Path.  For SONET, the assigned types are
               the STS-Nc SPEs, where N = 1, 3, 12, 24, and 48.
               STS-1 is equal to 51.84 Mbps.  For SDH, the assigned
               types are the STM-Nc VCs, where N = 1, 4, and 16."
          ::= { sonetPathCurrentEntry 1 }

          sonetPathCurrentStatus OBJECT-TYPE
              SYNTAX  Integer32 (1..14)
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                "This variable indicates the
                status of the interface.
                The sonetPathCurrentStatus
                is a bit map represented
                as a sum, therefore,
                it can represent multiple defects
                simultaneously.
                The sonetPathNoDefect should be
                set if and only if
                no other flag is set.

                The various bit positions are:
                   1   sonetPathNoDefect
                   2   sonetPathSTSLOP



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                   4   sonetPathSTSAIS
                   8   sonetPathSTSRDI
                  16   sonetPathUnequipped
                  32   sonetPathSignalLabelMismatch"
          ::= { sonetPathCurrentEntry 2 }

          sonetPathCurrentESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of Errored
               Seconds encountered by a SONET/SDH
               Path in the current 15 minute interval."
          ::= { sonetPathCurrentEntry 3 }

          sonetPathCurrentSESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of
               Severely Errored Seconds
               encountered by a SONET/SDH Path in the current 15
               minute
               interval."
          ::= { sonetPathCurrentEntry 4 }

          sonetPathCurrentCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of Coding
               Violations encountered by a
               SONET/SDH Path in the current 15 minute interval."
          ::= { sonetPathCurrentEntry 5 }

          sonetPathCurrentUASs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of
               Unavailable Seconds
               encountered by a Path in the current
               15 minute, interval."
          ::= { sonetPathCurrentEntry 6 }



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          -- the SONET/SDH Path Interval Table

          -- The SONET/SDH Path Interval Table
          -- contains various statistics
          -- collected by each system over a maximum
          -- of the previous 24 hours of
          -- operation.  The past 24 hours may be broken into 96
          -- completed 15 minute intervals.
          -- A system is required to store at
          -- least 4 completed 15 minute interval.
          -- The default value is 32 intervals.

          sonetPathIntervalTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetPathIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
               "The SONET/SDH Path Interval table."
          ::= { sonetPath 2 }

          sonetPathIntervalEntry OBJECT-TYPE
              SYNTAX  SonetPathIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
               "An entry in the SONET/SDH Path Interval table."
              INDEX   { ifIndex,
                        sonetPathIntervalNumber }
          ::= { sonetPathIntervalTable 1 }


          SonetPathIntervalEntry ::=
              SEQUENCE {
                   sonetPathIntervalNumber     Integer32,
                   sonetPathIntervalESs        Gauge32,
                   sonetPathIntervalSESs       Gauge32,
                   sonetPathIntervalCVs        Gauge32,
                   sonetPathIntervalUASs       Gauge32
              }


          sonetPathIntervalNumber OBJECT-TYPE
              SYNTAX  Integer32 (1..96)
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                 "A number between 1 and 96, which identifies the
                 interval for which the set of statistics is available.



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                 The interval identified by 1 is the most recently
                 completed 15 minute interval,
                 and the interval identified
                 by N is the interval immediately preceding the
                 one identified
                 by N-1."
          ::= { sonetPathIntervalEntry 1 }

          sonetPathIntervalESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of
               Errored Seconds encountered
               by a SONET/SDH Path in a
               particular 15-minute interval
               in the past 24 hours."
          ::= { sonetPathIntervalEntry 2 }

          sonetPathIntervalSESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of
               Severely Errored Seconds
               encountered by a SONET/SDH Path in
               a particular 15-minute interval
               in the past 24 hours."
          ::= { sonetPathIntervalEntry 3 }

          sonetPathIntervalCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of Coding
               Violations encountered by a
               SONET/SDH Path in a particular 15-minute interval
               in the past 24 hours."
          ::= { sonetPathIntervalEntry 4 }

          sonetPathIntervalUASs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION



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               "The counter associated with the number of
               Unavailable Seconds
               encountered by a Path in a
               particular 15-minute interval
               in the past 24 hours."
          ::= { sonetPathIntervalEntry 5 }


          -- The SONET/SDH Far End Path group

          -- This group consists of two tables:
          --  - SONET/SDH Far End Path Current Table
          --  - SONET/SDH Far End Path Interval Table

          -- The SONET/SDH Far End Path Current Table

          -- The SONET/SDH Far End Path Current table
          -- contains various statistics
          -- being collected for the current 15 minute interval.
          -- The statistics are collected from
          -- the far end block error code
          -- (FEBE) within the G1 byte of the Path Overhead.
          -- The definitions are the same as described for
          -- the near-end information.

          sonetFarEndPathCurrentTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetFarEndPathCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                   "The SONET/SDH Far End Path Current table."
              ::= { sonetFarEndPath 1 }

          sonetFarEndPathCurrentEntry OBJECT-TYPE
              SYNTAX  SonetFarEndPathCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                   "An entry in the SONET/SDH Far End Path Current table."
              INDEX   { ifIndex }
              ::= { sonetFarEndPathCurrentTable 1 }

          SonetFarEndPathCurrentEntry ::=
              SEQUENCE {
                  sonetFarEndPathCurrentESs       Gauge32,
                  sonetFarEndPathCurrentSESs      Gauge32,
                  sonetFarEndPathCurrentCVs       Gauge32,
                  sonetFarEndPathCurrentUASs      Gauge32



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              }


          sonetFarEndPathCurrentESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                   "The counter associated with the number of Far
                   Far End Errored Seconds encountered by a SONET/SDH
                   interface in the current 15 minute interval."
              ::= { sonetFarEndPathCurrentEntry 1 }

          sonetFarEndPathCurrentSESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                   "The counter associated with the number of
                   Far End Severely Errored Seconds
                   encountered by a SONET/SDH Path
                   interface in the current 15 minute
                   interval."
              ::= { sonetFarEndPathCurrentEntry 2 }

          sonetFarEndPathCurrentCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                   "The counter associated with the number of
                   Far End Coding Violations reported via
                   the far end block error count
                   encountered by a
                   SONET/SDH Path interface in
                   the current 15 minute interval."
              ::= { sonetFarEndPathCurrentEntry 3 }

          sonetFarEndPathCurrentUASs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                 "The counter associated with the number of
                 Far End Unavailable Seconds
                 encountered by a
                 SONET/SDH Path interface in
                 the current 15 minute interval."



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             ::= { sonetFarEndPathCurrentEntry 4 }


          -- The SONET/SDH Far End Path Interval Table

          -- The SONET/SDH Far End Path Interval Table
          -- contains various statistics
          -- collected by each system over a maximum
          -- of the previous 24 hours of
          -- operation.  The past 24 hours may be broken into 96
          -- completed 15 minute intervals.
          -- A system is required to store at
          -- least 4 completed 15 minute interval.
          -- The default value is 32 intervals.

          sonetFarEndPathIntervalTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetFarEndPathIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                  "The SONET/SDH Far End Path Interval table."
              ::= { sonetFarEndPath 2 }

          sonetFarEndPathIntervalEntry OBJECT-TYPE
              SYNTAX  SonetFarEndPathIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                 "An entry in the SONET/SDH Far
                 End Path Interval table."
              INDEX   { ifIndex,
                        sonetFarEndPathIntervalNumber }
              ::= { sonetFarEndPathIntervalTable 1 }

          SonetFarEndPathIntervalEntry ::=
              SEQUENCE {
                   sonetFarEndPathIntervalNumber     Integer32,
                   sonetFarEndPathIntervalESs        Gauge32,
                   sonetFarEndPathIntervalSESs       Gauge32,
                   sonetFarEndPathIntervalCVs        Gauge32,
                   sonetFarEndPathIntervalUASs       Gauge32
              }


          sonetFarEndPathIntervalNumber OBJECT-TYPE
             SYNTAX  Integer32 (1..96)
             MAX-ACCESS  not-accessible
             STATUS  current



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             DESCRIPTION
                  "A number between 1 and 96, which identifies the
                  interval for which the set of statistics is available.
                  The interval identified by 1 is the most recently
                  completed 15 minute interval,
                  and the interval identified
                  by N is the interval immediately preceding the
                  one identified
                  by N-1."
             ::= { sonetFarEndPathIntervalEntry 1 }

          sonetFarEndPathIntervalESs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                  "The counter associated with the number of
                  Far End Errored Seconds encountered
                  by a SONET/SDH Path interface in a
                  particular 15-minute interval
                  in the past 24 hours."
             ::= { sonetFarEndPathIntervalEntry 2 }

          sonetFarEndPathIntervalSESs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                  "The counter associated with the number of
                  Far End Severely Errored Seconds
                  encountered by a SONET/SDH Path interface
                  in a particular 15-minute interval
                  in the past 24 hours."
             ::= { sonetFarEndPathIntervalEntry 3 }

          sonetFarEndPathIntervalCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                   "The counter associated with the number of
                   Far End Coding Violations reported via
                   the far end block error count
                   encountered by a
                   SONET/SDH Path interface
                   in a particular 15-minute interval
                   in the past 24 hours."
              ::= { sonetFarEndPathIntervalEntry 4 }



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          sonetFarEndPathIntervalUASs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                 "The counter associated with the number of
                 Far End Unavailable Seconds
                 encountered by a
                 SONET/SDH Path interface in
                 a particular 15-minute interval
                 in the past 24 hours."
             ::= { sonetFarEndPathIntervalEntry 5 }


          -- the SONET/SDH Virtual Tributary group

          -- this group consists of 2 tables:
          -- - the SONET/SDH VT Current Table
          -- - the SONET/SDH VT Interval Table

          -- For SDH signals, virtual tributaries are
          -- called VCs instead of VTs

          -- A VT1.5 = VC11
          -- A VT2 = VC12
          -- A VT3 = none
          -- A VT6 = VC3


          -- the SONET/SDH VT Current Table

          -- The SONET/SDH VT current table
          -- contains various statistics
          -- being collected for the
          -- current 15 minute interval.

          sonetVTCurrentTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetVTCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
               "The SONET/SDH VT Current table."
          ::= { sonetVT 1 }

          sonetVTCurrentEntry OBJECT-TYPE
              SYNTAX  SonetVTCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current



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              DESCRIPTION
               "An entry in the SONET/SDH VT Current table."
              INDEX   { ifIndex }
          ::= { sonetVTCurrentTable 1 }

          SonetVTCurrentEntry ::=
              SEQUENCE {
                  sonetVTCurrentWidth      INTEGER,
                  sonetVTCurrentStatus     Integer32,
                  sonetVTCurrentESs        Gauge32,
                  sonetVTCurrentSESs       Gauge32,
                  sonetVTCurrentCVs        Gauge32,
                  sonetVTCurrentUASs       Gauge32
              }


          sonetVTCurrentWidth OBJECT-TYPE
              SYNTAX  INTEGER {
                      vtWidth15VC11(1),
                      vtWidth2VC12(2),
                      vtWidth3(3),
                      vtWidth6VC2(4),
                      vtWidth6c(5)
                   }
              MAX-ACCESS  read-write
              STATUS  current
              DESCRIPTION
              "A value that indicates the type of the SONET
               VT and SDH VC.  Assigned widths are
               VT1.5/VC11, VT2/VC12, VT3, VT6/VC2, and VT6c."
          ::= { sonetVTCurrentEntry 1 }

          sonetVTCurrentStatus OBJECT-TYPE
              SYNTAX  Integer32 (1..30)
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                "This variable indicates the
                status of the interface.
                The sonetVTCurrentStatus
                is a bit map represented
                as a sum, therefore,
                it can represent multiple defects
                and failures
                simultaneously.
                The sonetVTNoDefect should be
                set if and only if
                no other flag is set.



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RFC 1595                   SONET/SDH Objects                  March 1994


                The various bit positions are:
                   1   sonetVTNoDefect
                   2   sonetVTLOP
                   4   sonetVTPathAIS
                   8   sonetVTPathRDI
                  16   sonetVTPathRFI
                  32   sonetVTUnequipped
                  64   sonetVTSignalLabelMismatch"
          ::= { sonetVTCurrentEntry 2 }

          sonetVTCurrentESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of Errored
               Seconds encountered by a SONET/SDH
               VT in the current 15 minute interval."
          ::= { sonetVTCurrentEntry 3 }

          sonetVTCurrentSESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of
               Severely Errored Seconds
               encountered by a SONET/SDH VT in the current 15 minute
               interval."
          ::= { sonetVTCurrentEntry 4 }

          sonetVTCurrentCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of Coding
               Violations encountered by a
               SONET/SDH VT in the current 15 minute interval."
          ::= { sonetVTCurrentEntry 5 }

          sonetVTCurrentUASs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of
               Unavailable Seconds



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RFC 1595                   SONET/SDH Objects                  March 1994


               encountered by a VT in the current
               15 minute, interval."
          ::= { sonetVTCurrentEntry 6 }


          -- the SONET/SDH VT Interval Table

          -- The SONET/SDH VT Interval Table
          -- contains various statistics
          -- collected by each system over a maximum
          -- of the previous 24 hours of
          -- operation.  The past 24 hours may be broken into 96
          -- completed 15 minute intervals.
          -- A system is required to store at
          -- least 4 completed 15 minute interval.
          -- The default value is 32 intervals.

          sonetVTIntervalTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetVTIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
               "The SONET/SDH VT Interval table."
          ::= { sonetVT 2 }

          sonetVTIntervalEntry OBJECT-TYPE
              SYNTAX  SonetVTIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
               "An entry in the SONET/SDH VT Interval table."
              INDEX   { ifIndex,
                        sonetVTIntervalNumber }
          ::= { sonetVTIntervalTable 1 }

          SonetVTIntervalEntry ::=
              SEQUENCE {
                  sonetVTIntervalNumber     Integer32,
                  sonetVTIntervalESs        Gauge32,
                  sonetVTIntervalSESs       Gauge32,
                  sonetVTIntervalCVs        Gauge32,
                  sonetVTIntervalUASs       Gauge32
              }


          sonetVTIntervalNumber OBJECT-TYPE
              SYNTAX  Integer32 (1..96)
              MAX-ACCESS  not-accessible



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              STATUS  current
              DESCRIPTION
                "A number between 1 and 96, which identifies the
                interval for which the set of statistics is available.
                The interval identified by 1 is the most recently
                completed 15 minute interval,
                and the interval identified
                by N is the interval immediately preceding the
                one identified
                by N-1."
          ::= { sonetVTIntervalEntry 1 }

          sonetVTIntervalESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of
               Errored Seconds encountered
               by a SONET/SDH VT in a particular 15-minute interval
               in the past 24 hours."
          ::= { sonetVTIntervalEntry 2 }

          sonetVTIntervalSESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of
               Severely Errored Seconds
               encountered by a SONET/SDH VT
               in a particular 15-minute interval
               in the past 24 hours."
          ::= { sonetVTIntervalEntry 3 }

          sonetVTIntervalCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of Coding
               Violations encountered by a
               SONET/SDH VT in a particular 15-minute interval
               in the past 24 hours."
          ::= { sonetVTIntervalEntry 4 }

          sonetVTIntervalUASs OBJECT-TYPE
              SYNTAX  Gauge32



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              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
               "The counter associated with the number of
               Unavailable Seconds
               encountered by a VT in a particular 15-minute interval
               in the past 24 hours."
          ::= { sonetVTIntervalEntry 5 }


          -- The SONET/SDH Far End VT group

          -- This group consists of two tables:
          --    SONET/SDH Far End VT Current Table
          --    SONET/SDH Far End VT Interval Table


          -- The SONET/SDH Far End VT Current

          -- The SONET/SDH Far End VT Current table
          -- contains various statistics
          -- being collected for the current 15 minute interval.
          -- The statistics are collected from
          -- the far end block error code
          -- (FEBE) within the G1 byte of the VT Overhead.
          -- The definitions are the same as described for
          -- the near-end information.

          sonetFarEndVTCurrentTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetFarEndVTCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                  "The SONET/SDH Far End VT Current table."
              ::= { sonetFarEndVT 1 }

          sonetFarEndVTCurrentEntry OBJECT-TYPE
              SYNTAX  SonetFarEndVTCurrentEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                  "An entry in the SONET/SDH Far End VT Current table."
              INDEX   { ifIndex }
              ::= { sonetFarEndVTCurrentTable 1 }

          SonetFarEndVTCurrentEntry ::=
              SEQUENCE {
                  sonetFarEndVTCurrentESs       Gauge32,



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                  sonetFarEndVTCurrentSESs      Gauge32,
                  sonetFarEndVTCurrentCVs       Gauge32,
                  sonetFarEndVTCurrentUASs      Gauge32
              }


          sonetFarEndVTCurrentESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                  "The counter associated with the number of Far
                  Far End Errored Seconds encountered by a SONET/SDH
                  interface in the current 15 minute interval."
          ::= { sonetFarEndVTCurrentEntry 1 }

          sonetFarEndVTCurrentSESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                  "The counter associated with the number of
                  Far End Severely Errored Seconds
                  encountered by a SONET/SDH VT interface
                  in the current 15 minute
                  interval."
              ::= { sonetFarEndVTCurrentEntry 2 }

          sonetFarEndVTCurrentCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                  "The counter associated with the number of
                  Far End Coding Violations reported via
                  the far end block error count
                  encountered by a
                  SONET/SDH VT interface
                  in the current 15 minute interval."
              ::= { sonetFarEndVTCurrentEntry 3 }

          sonetFarEndVTCurrentUASs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                "The counter associated with the number of
                Far End Unavailable Seconds



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                encountered by a
                SONET/SDH VT interface
                in the current 15 minute interval."
             ::= { sonetFarEndVTCurrentEntry 4 }


          -- The SONET/SDH Far End VT Interval Table

          -- The SONET/SDH Far End VT Interval Table
          -- contains various statistics
          -- collected by each system over a maximum
          -- of the previous 24 hours of
          -- operation.  The past 24 hours may be broken into 96
          -- completed 15 minute intervals.
          -- A system is required to store at
          -- least 4 completed 15 minute interval.
          -- The default value is 32 intervals.

          sonetFarEndVTIntervalTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF SonetFarEndVTIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                 "The SONET/SDH Far End VT Interval table."
              ::= { sonetFarEndVT 2 }

          sonetFarEndVTIntervalEntry OBJECT-TYPE
              SYNTAX  SonetFarEndVTIntervalEntry
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                "An entry in the SONET/SDH Far
                End VT Interval table."
              INDEX   { ifIndex,
                        sonetFarEndVTIntervalNumber }
              ::= { sonetFarEndVTIntervalTable 1 }

          SonetFarEndVTIntervalEntry ::=
             SEQUENCE {
                   sonetFarEndVTIntervalNumber     Integer32,
                   sonetFarEndVTIntervalESs        Gauge32,
                   sonetFarEndVTIntervalSESs       Gauge32,
                   sonetFarEndVTIntervalCVs        Gauge32,
                   sonetFarEndVTIntervalUASs       Gauge32
              }


          sonetFarEndVTIntervalNumber OBJECT-TYPE



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              SYNTAX  Integer32 (1..96)
              MAX-ACCESS  not-accessible
              STATUS  current
              DESCRIPTION
                 "A number between 1 and 96, which identifies the
                 interval for which the set of statistics is available.
                 The interval identified by 1 is the most recently
                 completed 15 minute interval,
                 and the interval identified
                 by N is the interval immediately preceding the
                 one identified
                 by N-1."
              ::= { sonetFarEndVTIntervalEntry 1 }

          sonetFarEndVTIntervalESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                    "The counter associated with the number of
                    Far End Errored Seconds encountered
                    by a SONET/SDH VT interface
                    in a particular 15-minute interval
                    in the past 24 hours."
             ::= { sonetFarEndVTIntervalEntry 2 }

          sonetFarEndVTIntervalSESs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                    "The counter associated with the number of
                    Far End Severely Errored Seconds
                    encountered by a SONET/SDH VT interface
                    in a particular 15-minute interval
                    in the past 24 hours."
              ::= { sonetFarEndVTIntervalEntry 3 }

          sonetFarEndVTIntervalCVs OBJECT-TYPE
              SYNTAX  Gauge32
              MAX-ACCESS  read-only
              STATUS  current
              DESCRIPTION
                   "The counter associated with the number of
                   Far End Coding Violations reported via
                   the far end block error count
                   encountered by a
                   SONET/SDH VT interface in a



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                   particular 15-minute interval
                   in the past 24 hours."
              ::= { sonetFarEndVTIntervalEntry 4 }

          sonetFarEndVTIntervalUASs OBJECT-TYPE
             SYNTAX  Gauge32
             MAX-ACCESS  read-only
             STATUS  current
             DESCRIPTION
                 "The counter associated with the number of
                 Far End Unavailable Seconds
                 encountered by a
                 SONET/SDH VT interface in a
                 particular 15-minute interval
                 in the past 24 hours."
             ::= { sonetFarEndVTIntervalEntry 5 }


          -- conformance information

          sonetConformance OBJECT IDENTIFIER ::= { sonetMIB 4 }

          sonetGroups      OBJECT IDENTIFIER ::= { sonetConformance 1 }
          sonetCompliances OBJECT IDENTIFIER ::= { sonetConformance 2 }


          -- compliance statements

          sonetCompliance MODULE-COMPLIANCE
              STATUS  current
              DESCRIPTION
                      "The compliance statement for SONET/SDH
                       interfaces."

              MODULE  -- this module
                  MANDATORY-GROUPS { sonetMediumStuff, sonetSectionStuff }

                  GROUP       sonetLineStuff
                  DESCRIPTION
                      "Implementation of this group is mandatory for all
                       SONET/SDH systems that terminate SONET/SDH Lines,
                       Paths or Virtual Tributaries."

                  GROUP       sonetFarEndLineStuff
                  DESCRIPTION
                      "Implementation of this group is optional for all
                       SONET/SDH systems that terminate SONET/SDH Lines,
                       Paths or Virtual Tributaries, and that



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                       provide for a far end block error (FEBE)
                       information at the SONET/SDH Line Layer."

                  GROUP       sonetPathStuff
                  DESCRIPTION
                      "Implementation of this group is mandatory for all
                       SONET/SDH systems that terminate SONET/SDH
                       Paths or Virtual
                       Tributaries."

                  OBJECT      sonetPathWidth
                  MIN-ACCESS  read-only
                  DESCRIPTION
                      "Write access is not required."

                  GROUP       sonetFarEndPathStuff
                  DESCRIPTION
                      "Implementation of this group is optional for all
                       SONET/SDH systems that terminate SONET/SDH
                       Paths or Virtual
                       Tributaries, and that process
                       Far End information."

                  GROUP       sonetVTStuff
                  DESCRIPTION
                      "Implementation of this group is mandatory for all
                       SONET/SDH systems that terminate SONET/SDH
                       Virtual Tributaries."

                  OBJECT      sonetVTWidth
                  MIN-ACCESS  read-only
                  DESCRIPTION
                      "Write access is not required."

                  GROUP       sonetFarEndVTStuff
                  DESCRIPTION
                      "Implementation of this group is optional for
                       all SONET/SDH systems that terminate the
                       SONET/SDH floating Virtual Tributaries, and
                       that process Far End information."

              ::= { sonetCompliances 1 }

          -- units of conformance

          sonetMediumStuff    OBJECT-GROUP
              OBJECTS { sonetMediumType,
                        sonetMediumTimeElapsed,



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                        sonetMediumValidIntervals,
                        sonetMediumLineCoding,
                        sonetMediumLineType,
                        sonetMediumCircuitIdentifier }
              STATUS  current
              DESCRIPTION
                      "A collection of objects providing configuration
                      information applicable to all SONET/SDH
                      interfaces."
              ::= { sonetGroups 1 }

          sonetSectionStuff    OBJECT-GROUP
              OBJECTS { sonetSectionCurrentStatus,
                        sonetSectionCurrentESs,
                        sonetSectionCurrentSESs,
                        sonetSectionCurrentSEFSs,
                        sonetSectionCurrentCVs,
                        sonetSectionIntervalESs,
                        sonetSectionIntervalSESs,
                        sonetSectionIntervalSEFSs,
                        sonetSectionIntervalCVs
           }
              STATUS  current
              DESCRIPTION
                      "A collection of objects providing information
                      specific to SONET/SDH Section interfaces."
              ::= { sonetGroups 2 }

          sonetLineStuff    OBJECT-GROUP
              OBJECTS { sonetLineCurrentStatus,
                        sonetLineCurrentESs,
                        sonetLineCurrentSESs,
                        sonetLineCurrentCVs,
                        sonetLineCurrentUASs,
                        sonetLineIntervalESs,
                        sonetLineIntervalSESs,
                        sonetLineIntervalCVs,
                        sonetLineIntervalUASs }
              STATUS  current
              DESCRIPTION
                      "A collection of objects providing information
                      specific to SONET/SDH Line interfaces."
              ::= { sonetGroups 3 }

          sonetFarEndLineStuff    OBJECT-GROUP
              OBJECTS { sonetFarEndLineCurrentESs,
                        sonetFarEndLineCurrentSESs,
                        sonetFarEndLineCurrentCVs,



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                        sonetFarEndLineCurrentUASs,
                        sonetFarEndLineIntervalESs,
                        sonetFarEndLineIntervalSESs,
                        sonetFarEndLineIntervalCVs,
                        sonetFarEndLineIntervalUASs }
              STATUS  current
              DESCRIPTION
                      "A collection of objects providing information
                      specific to SONET/SDH Line interfaces,
                      and maintaining Line Far End information."
              ::= { sonetGroups 4 }

          sonetPathStuff    OBJECT-GROUP
              OBJECTS { sonetPathCurrentWidth,
                        sonetPathCurrentStatus,
                        sonetPathCurrentESs,
                        sonetPathCurrentSESs,
                        sonetPathCurrentCVs,
                        sonetPathCurrentUASs,
                        sonetPathIntervalESs,
                        sonetPathIntervalSESs,
                        sonetPathIntervalCVs,
                        sonetPathIntervalUASs }
              STATUS  current
              DESCRIPTION
                      "A collection of objects providing information
                      specific to SONET/SDH Path interfaces."
              ::= { sonetGroups 5 }

          sonetFarEndPathStuff    OBJECT-GROUP
              OBJECTS { sonetFarEndPathCurrentESs,
                        sonetFarEndPathCurrentSESs,
                        sonetFarEndPathCurrentCVs,
                        sonetFarEndPathCurrentUASs,
                        sonetFarEndPathIntervalESs,
                        sonetFarEndPathIntervalSESs,
                        sonetFarEndPathIntervalCVs,
                        sonetFarEndPathIntervalUASs }
              STATUS  current
              DESCRIPTION
                      "A collection of objects providing information
                      specific to SONET/SDH Path interfaces,
                      and maintaining Path Far End information."
              ::= { sonetGroups 6 }

          sonetVTStuff    OBJECT-GROUP
              OBJECTS { sonetVTCurrentWidth,
                        sonetVTCurrentStatus,



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                        sonetVTCurrentESs,
                        sonetVTCurrentSESs,
                        sonetVTCurrentCVs,
                        sonetVTCurrentUASs,
                        sonetVTIntervalESs,
                        sonetVTIntervalSESs,
                        sonetVTIntervalCVs,
                        sonetVTIntervalUASs }
              STATUS  current
              DESCRIPTION
                      "A collection of objects providing information
                      specific to SONET/SDH VT interfaces."
              ::= { sonetGroups 7 }

          sonetFarEndVTStuff    OBJECT-GROUP
              OBJECTS { sonetFarEndVTCurrentESs,
                        sonetFarEndVTCurrentSESs,
                        sonetFarEndVTCurrentCVs,
                        sonetFarEndVTCurrentUASs,
                        sonetFarEndVTIntervalESs,
                        sonetFarEndVTIntervalSESs,
                        sonetFarEndVTIntervalCVs,
                        sonetFarEndVTIntervalUASs }
              STATUS  current
              DESCRIPTION
                      "A collection of objects providing information
                      specific to SONET/SDH VT interfaces,
                      and maintaining VT Far End information."
              ::= { sonetGroups 8 }



          END

5.  Acknowledgments

   This specification is a product of the AToM MIB Working Group.














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6.  References

   [1] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Structure
       of Management Information for version 2 of the Simple Network
       Management Protocol (SNMPv2)", RFC 1442, SNMP Research, Inc.,
       Hughes LAN Systems, Dover Beach Consulting, Inc., Carnegie Mellon
       University, April 1993.

   [2] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Textual
       Conventions for version 2 of the the Simple Network Management
       Protocol (SNMPv2)", RFC 1443, SNMP Research, Inc., Hughes LAN
       Systems, Dover Beach Consulting, Inc., Carnegie Mellon
       University, April 1993.

   [3] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser,
       "Conformance Statements for version 2 of the the Simple Network
       Management Protocol (SNMPv2)", RFC 1444, SNMP Research, Inc.,
       Hughes LAN Systems, Dover Beach Consulting, Inc., Carnegie Mellon
       University, April 1993.

   [4] Galvin, J., and K. McCloghrie, "Administrative Model for version
       2 of the Simple Network Management Protocol (SNMPv2)", RFC 1445,
       Trusted Information Systems, Hughes LAN Systems, April 1993.

   [5] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Protocol
       Operations for version 2 of the Simple Network Management
       Protocol (SNMPv2)", RFC 1448, SNMP Research, Inc., Hughes LAN
       Systems, Dover Beach Consulting, Inc., Carnegie Mellon
       University, April 1993.

   [6] McCloghrie, K., and M. Rose, "Management Information Base for
       Network Management of TCP/IP-based internets: MIB-II", STD 17,
       RFC 1213, Hughes LAN Systems, Inc., 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 Notation One
       (ASN.1), International Organization for Standardization.
       International Standard 8825, (December, 1987).

   [9] American National Standard for Telecommunications - Digital
       Hierarchy - Optical Interface Rates and Formats Specification,
       ANSI T1.105-1988.



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  [9a] ANSI T1.105-1991.

  [10] American National Standard for Telecommunications - Digital
       Hierarchy - Optical Interface Specification (Single-Mode), ANSI
       T1.106-1988.

  [11] American National Standard for Telecommunications -- Layer 1 In-
       Service Digital Transmission Performance Monitoring T1M1.3/93-
       005R2, July 1993.

  [12] McCloghrie, K.,  and F. Kastenholz, "Evolution of Interfaces
       Group of MIB-II", RFC 1573, Hughes LAN Systems, FTP Software,
       January 1994.

  [13] Cox, T., and K. Tesink, Editors, "Definitions of Managed Objects
       for the DS3/E3 Interface Type", RFC 1407, Bellcore, January 1993.

  [14] Baker, F.,  and J. Watt, Editors, "Definitions of Managed Objects
       for the DS1/E1 Interface Type", RFC 1406, Advanced Computer
       Communications, Newbridge Networks Corporation, January 1993.

  [15] CCITT Recommendation G.707, "Synchronous Digital Hierarchy Bit
       Rates", June 1992.

  [16] CCITT Recommendation G.708, "Network Node Interface for the
       Synchronous Digital Hierarchy", June 1992.

  [17] CCITT Recommendation G.709, "Synchronous Multiplexing Structure",
       June 1992.

  [18] CCITT Recommendation G.783, "Characteristics of Synchronous
       Digital Hierarchy (SDH) Multiplexing Equipment Functional
       Blocks", November 1992.


















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RFC 1595                   SONET/SDH Objects                  March 1994


7.  Security Considerations

   Security issues are not discussed in this memo.

8.  Authors' Addresses

   Tracy A. Brown
   Bell Communications Research
   331 Newman Springs Road
   P.O. Box 7020
   Red Bank, NJ  07701-7020

   Phone: (908) 758-2107
   EMail: tacox@mail.bellcore.com


   Kaj Tesink
   Bell Communications Research
   331 Newman Springs Road
   P.O. Box 7020
   Red Bank, NJ  07701-7020

   Phone: (908) 758-5254
   EMail: kaj@cc.bellcore.com



























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