Network Working Group                                            T. Cox
Request for Comments: 1233                                    K. Tesink
                                           Bell Communications Research
                                                                Editors
                                                               May 1991


                     Definitions of Managed Objects
                       for the DS3 Interface Type

Status of this Memo

   This memo defines objects for managing DS3 Interface objects for use
   with the SNMP protocol.  This memo is a product of the SNMP and
   Transmission MIB Working Group of the Internet Engineering Task Force
   (IETF).  This RFC specifies an IAB standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "IAB
   Official Protocol Standards" for the standardization state and status
   of this protocol.  Distribution of this memo is unlimited.

Table of Contents

   1. Abstract ..............................................    1
   2. The Network Management Framework.......................    2
   3. Objects ...............................................    2
   3.1 Format of Definitions ................................    3
   4. Overview ..............................................    3
   4.1 Binding between Interfaces and CSUs ..................    3
   4.2 Objectives of this MIB Module ........................    3
   4.3 DS3 Terminology ......................................    3
   5. Object Definitions ....................................    5
   5.1 The DS3 Configuration Group ..........................    6
   5.2 The DS3 Interval Group ...............................   11
   5.3 The DS3 Current Group ................................   14
   5.4 The DS3 Total Group ..................................   17
   6. Acknowledgments .......................................   20
   7. References ............................................   22
   8. Security Considerations................................   23
   9. Authors' Addresses.....................................   23

1.  Abstract

   This memo defines an experimental portion of the Management
   Information Base (MIB) for use with network management protocols in
   TCP/IP-based internets.  In particular, this memo defines MIB objects
   for representing DS3 physical interfaces.  Implementors should
   consult in addition to this memo the companion document that



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   describes that DS1 managed objects.

2.  The Network Management Framework

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

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

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

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

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

3.  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 [3] 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.



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3.1.  Format of Definitions

   Section 5 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 [13].

4.  Overview

   These objects are used when the particular media being used to
   realize an interface is a DS3 interface.  At present, this applies to
   these values of the ifType variable in the Internet-standard MIB:

               ds3 (30)

   The definitions contained herein are based on the DS3 specifications
   in ANSI T1.102-1987, ANSI T1.107-1988, and ANSI T1.404-1989
   [9,10,11].

4.1.  Binding between Interfaces and CSUs

   Each agent which resides on a host which uses DS3 interfaces is
   required to assign a small, positive integer uniquely to each CSU.
   This is known as the "CSUIndex", and is used to distinguish between
   different CSUs attached to a node.  The CSUIndex is also used as the
   "key" when accessing tabular information about DS3 interfaces.

   The ds3Index column of the DS3 Configuration table relates each CSU
   to its corresponding interface in the Internet-standard MIB.

4.2.  Objectives of this MIB Module

   There are numerous things that could be included in a MIB for DS3
   signals: the management of multiplexors, CSUs, DSUs, and the like.
   The intent of this document is to facilitate the common management of
   CSUs, both in-chassis and external via proxy.  As such, a design
   decision was made up front to very closely align the MIB with the set
   of objects that can generally be read from CSUs that are currently
   deployed.

4.3.  DS3 Terminology

   The terminology used in this document to describe error conditions on
   a DS3 circuit as monitored by a DS3 CSU are from the ANSI T1M1.3/90
   draft standard [12].

          Out of Frame (OOF) event
               An OOF event is detected when any three or more errors in



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               sixteen or fewer consecutive F-bits occur within a DS3
               M-frame.  An OOF event is cleared when reframe occurs.

          Loss of Signal (LOS)
               This state is declared upon observing 175 +/- 75
               contiguous pulse positions with no pulses of either
               positive or negative polarity.

          Coding Violation (CV)
               For all DS3 applications, a coding violation is a P-bit
               Parity Error event.  A P-bit Parity Error event is the
               occurrence of a received P-bit code on the DS3 M-frame
               that is not identical to the corresponding locally-
               calculated code.  For C-Bit Parity applications, it is
               also the occurrence of a received CP-Bit parity
               violation.  For SYNTRAN applications, it is also the
               occurrence of a received CRC-9 code that is not identical
               to the corresponding locally calculated code.

          Bipolar Violation (BPV)
               A bipolar violation, for B3ZS-coded signals, is the
               occurrence of a received bipolar violation that is not
               part of a zero-substitution code.  For B3ZS-coded
               signals, a bipolar violation may also include other error
               patterns such as:  three or more consecutive zeros and
               incorrect parity.

          Errored Seconds (ES)
               An ES is a second with one or more Coding Violation OR
               one or more Out of Frame events OR an AIS.

          Severely Errored Seconds (SES)
               A SES is a second with 44 or more Coding Violations OR
               one or more Out of Frame events OR an AIS.

          Severely Errored Framing Seconds (SEFS)
               A SEFS is a second with one or more Out of Frame events.

          Unavailable Seconds (UAS)
               UAS are calculated by counting the number of seconds that
               the CSU is in the Unavailable signal state (i.e.,
               declared a Red Alarm or a Yellow Alarm), including the
               initial 10 seconds to enter the state but not including
               the 10 seconds to exit the state.

               Note that any second that may be counted as an UAS may
               not be counted as an ES or a SES.  Since the 10 SESs that
               comprise the transition from the available to unavailable



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               signal state may also be counted as ESs and SESs previous
               to entering the state, these three counters are adjusted
               so that any second counted during this transition is then
               subtracted.  The 10 seconds in the transition from
               unavailable to available may be counted as ESs.

               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 ds3IntervalSES and ds3IntervalUAS 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.

          Yellow Alarm
               The Yellow Alarm is declared after detecting the Yellow
               Signal.  See ANSI T1.107-1989 [10].

          Red Alarm
               The Red Alarm is declared after detecting a Loss of
               Signal, a Loss of Frame (a persistent OOF event), or an
               Alarm Indication Signal, see [10] for at least 2-10
               seconds.  The Red Alarm is cleared at the onset of 10
               consecutive seconds with no SES.

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

5.  Object Definitions

               RFC1233-MIB DEFINITIONS ::= BEGIN

               IMPORTS
                       experimental, Counter
                               FROM RFC1155-SMI
                       DisplayString
                               FROM RFC1158-MIB
                       OBJECT-TYPE
                               FROM RFC-1212;

               --  This MIB module uses the extended OBJECT-TYPE macro
               --  as defined in [13].




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               --  this is the MIB module for the DS3 objects

               ds3     OBJECT IDENTIFIER ::= { experimental 15 }

               -- the DS3 Configuration group

               -- Although the objects in this group are read-only, at
               -- the agent's discretion they may be made read-write
               -- so that the management station, when appropriately
               -- authorized, may change the behavior of the CSU,
               -- e.g., to place the device into a loopback state.

               -- Implementation of this group is mandatory for all
               -- systems that attach to a DS3 Interface.

               ds3ConfigTable OBJECT-TYPE
                   SYNTAX  SEQUENCE OF DS3ConfigEntry
                   ACCESS  not-accessible
                   STATUS  mandatory
                   DESCRIPTION
                           "The DS3 Configuration table."
                  ::= { ds3 1 }

              ds3ConfigEntry OBJECT-TYPE
                  SYNTAX  DS3ConfigEntry
                  ACCESS  not-accessible
                  STATUS  mandatory
                  DESCRIPTION
                          "An entry in the DS3 Configuration table."
                 INDEX   { ds3CSUIndex }
                 ::= { ds3ConfigTable 1 }

             DS3ConfigEntry ::=
                 SEQUENCE {
                     ds3CSUIndex
                         INTEGER,
                     ds3Index
                         INTEGER,
                     ds3TimeElapsed
                         INTEGER (1..900),
                     ds3ValidIntervals
                         INTEGER (0..96),
                     ds3LineType
                         INTEGER,
                     ds3ZeroCoding
                         INTEGER,
                     ds3Loopback
                         INTEGER,



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                     ds3SendCode
                         INTEGER,
                     ds3YellowAlarm
                         INTEGER,
                     ds3RedAlarm
                         INTEGER,
                     ds3CircuitIdentifier
                         DisplayString (SIZE (0..255))
             }

             ds3CSUIndex OBJECT-TYPE
                 SYNTAX  INTEGER
                 ACCESS  read-only
                 STATUS  mandatory
                 DESCRIPTION
                         "The index value which uniquely identifies the
                         CSU to which this entry is applicable."
                ::= { ds3ConfigEntry 1 }

            ds3Index OBJECT-TYPE
                SYNTAX  INTEGER
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "An index value that uniquely identifies a DS3
                        Interface.  The interface identified by a
                        particular value of this index is the same
                        interface as identified by the same value an
                        ifIndex object instance."
               ::= { ds3ConfigEntry 2 }

           ds3TimeElapsed OBJECT-TYPE
               SYNTAX  INTEGER (1..900)
               ACCESS  read-only
               STATUS  mandatory
               DESCRIPTION
                       "The number of seconds, including partial
                       seconds, that have elapsed since the beginning of
                       the current error-measurement period."
              ::= { ds3ConfigEntry 3 }

          ds3ValidIntervals OBJECT-TYPE
              SYNTAX  INTEGER (0..96)
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The number of previous intervals for which valid
                      data was collected.  The value will be 96 unless



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                      the CSU device was brought online within the last
                      24 hours, in which case the value will be the
                      number of complete 15 minute intervals the CSU has
                      been online."
              ::= { ds3ConfigEntry 4 }

          ds3LineType OBJECT-TYPE
              SYNTAX  INTEGER {
                          other(1),
                          ds3M23(2),
                          ds3SYNTRAN(3),
                          ds3CbitParity(4),
                          ds3ClearChannel(5)
                      }
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "This variable indicates the variety of DS3 C-bit
                      application implementing this circuit.  The type
                      of circuit affects the interpretation of the usage
                      and error statistics.  The rate of all of them is
                      44.736 Mbps.

                      The values, in sequence, describe:
                      TITLE:            SPECIFICATION:
                      ds3M23            ANSI T1.107-1988 [10]
                      ds3SYNTRAN        ANSI T1.107-1988 [10]
                      ds3C-bitParity    ANSI T1.107a-1989 [10a]
                      ds3ClearChannel   ANSI T1.102-1987 [9]
                      "
              ::= { ds3ConfigEntry 5 }

          ds3ZeroCoding OBJECT-TYPE
              SYNTAX  INTEGER {
                          ds3other(1),
                          ds3B3ZS(2)
                      }
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "This variable describes the variety of Zero Code
                      Suppression used on the link, which in turn
                      affects a number of its characteristics.
                      ds3B3ZS refers to the use of specified patterns of
                      normal bits and bipolar violations which are used
                      to replace sequences of zero bits of a specified
                      length."
              ::= { ds3ConfigEntry 6 }



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          ds3Loopback OBJECT-TYPE
              SYNTAX  INTEGER {
                          ds3NoLoop(1),
                          ds3LocalLoopbackLocalSide(2),
                          ds3LocalLoopbackRemoteSide(3),
                          ds3RemoteLoopbackLocalSide(4),
                          ds3RemoteLoopbackRemoteSide(5)
                      }
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "This variable represents the loopback state of
                      the CSU.  Devices supporting read/write access
                      should return badValue in response to a requested
                      loopback state that the CSU does not support.  The
                      values mean:

                        ds3NoLoop
                           Not in the loopback state.  A device that is
                           not capable of performing a loopback on
                           either interface shall always return this as
                           it's value.

                        ds3LocalLoopbackLocalSide
                           Signal received from the local side of the
                           device is looped back at the local connector
                           (eg, without involving the CSU).

                        ds3LocalLoopbackRemoteSide
                           Signal received from the local side of the
                           device is looped back at the remote connector
                           (eg, through the CSU).

                        ds3RemoteLoopbackLocalSide
                           Signal received from the remote side of the
                           device is looped back at the local connector
                           (eg, through the CSU).

                        ds3RemoteLoopbackRemoteSide
                           Signal received from the remote side of the
                           device is looped back at the remote connector
                           (eg, without involving the CSU).

                      Note that M23 and ClearChannel interfaces do not
                      support the Loopback managed object."
              ::= { ds3ConfigEntry 7 }





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          ds3SendCode OBJECT-TYPE
              SYNTAX  INTEGER {
                          ds3SendTestMessage(1),
                          ds3SendNoCode(2),
                          ds3SendSetCode(3),
                          ds3SendLoopbackCode(4),
                          ds3SendResetCode(5)
                      }
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "This variable indicates what type of code is
                      being sent across the DS1 circuit by the CSU.  The
                      values mean:

                        ds3SendNoCode
                           sending looped or normal data

                        ds3SendSetCode
                           sending a loopback request

                        ds3SendLoopbackCode
                           sending the code to choose a specific
                           loopback

                        ds3SendResetCode
                           sending a loopback termination request

                        ds3SendTestMessage
                           sending a Test pattern as defined in
                           T1.107a-1989 [10a].
                      "
                       ::= { ds3ConfigEntry 8 }

                   ds3YellowAlarm OBJECT-TYPE
                       SYNTAX  INTEGER {
                                   ds3YellowAlarm(1),
                                   ds3NoYellowAlarm(2)
                               }
                       ACCESS  read-only
                       STATUS  mandatory
                       DESCRIPTION
                               "This variable indicates if a Yellow
                               Alarm condition exists."
                      ::= { ds3ConfigEntry 9 }

                  ds3RedAlarm OBJECT-TYPE
                      SYNTAX  INTEGER {



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                                  ds3RedAlarm(1),
                                  ds3NoRedAlarm(2)
                              }
                      ACCESS  read-only
                      STATUS  mandatory
                      DESCRIPTION
                              "This variable indicates if a Red Alarm
                              condition exists."
                     ::= { ds3ConfigEntry 10 }

                 ds3CircuitIdentifier OBJECT-TYPE
                     SYNTAX  DisplayString (SIZE (0..255))
                     ACCESS  read-only
                     STATUS  mandatory
                     DESCRIPTION
                             "This variable contains the transmission
                             vendor's circuit identifier, for the
                             purpose of facilitating troubleshooting."
                    ::= { ds3ConfigEntry 11 }


                -- the DS3 Interval group

                -- Implementation of this group is mandatory for all
                -- systems that attach to a DS3 interface.

                -- The DS3 Interval Table contains various statistics
                -- collected by each CSU over the previous 24 hours of
                -- operation.  The past 24 hours are broken into 96
                -- completed 15 minute intervals.

                ds3IntervalTable OBJECT-TYPE
                    SYNTAX  SEQUENCE OF DS3IntervalEntry
                    ACCESS  not-accessible
                    STATUS  mandatory
                    DESCRIPTION
                            "The DS3 Interval table."
                   ::= { ds3 2 }

               ds3IntervalEntry OBJECT-TYPE
                   SYNTAX  DS3IntervalEntry
                   ACCESS  not-accessible
                   STATUS  mandatory
                   DESCRIPTION
                           "An entry in the DS3 Interval table."
                  INDEX   { ds3IntervalIndex, ds3IntervalNumber }
                  ::= { ds3IntervalTable 1 }




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              DS3IntervalEntry ::=
                  SEQUENCE {
                      ds3IntervalIndex
                          INTEGER,
                      ds3IntervalNumber
                          INTEGER (1..96),
                      ds3IntervalESs
                          Counter,
                      ds3IntervalSESs
                          Counter,
                      ds3IntervalSEFSs
                          Counter,
                      ds3IntervalUASs
                          Counter,
                      ds3IntervalCSSs
                          Counter,
                      ds3IntervalBPVs
                          Counter,
                      ds3IntervalCVs
                          Counter
                  }

              ds3IntervalIndex OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The index value which uniquely identifies the
                          CSU to which this entry is applicable.  The
                          interface identified by a particular value of
                          this index is the same interface as identified
                          by the same value an DS3CSUIndex object
                          instance."
                 ::= { ds3IntervalEntry 1 }

             ds3IntervalNumber OBJECT-TYPE
                 SYNTAX  INTEGER (1..96)
                 ACCESS  read-only
                 STATUS  mandatory
                 DESCRIPTION
                         "A number between 1 and 96, where 1 is the most
                         recently completed 15 minute interval and 96 is
                         the least recently completed 15 minutes
                         interval (assuming that all 96 intervals are
                         valid)."
                ::= { ds3IntervalEntry 2 }





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            ds3IntervalESs OBJECT-TYPE
                SYNTAX  Counter
                ACCESS  read-only
                STATUS  mandatory
                DESCRIPTION
                        "The counter associated with the number of
                        Errored Seconds, as defined by [12], encountered
                        by a DS3 CSU in one of the previous 96,
                        individual 15 minute, intervals."
               ::= { ds3IntervalEntry 3 }

           ds3IntervalSESs OBJECT-TYPE
               SYNTAX  Counter
               ACCESS  read-only
               STATUS  mandatory
               DESCRIPTION
                       "The counter associated with the number of
                       Severely Errored Seconds, as defined by [12],
                       encountered by a DS3 CSU in one of the previous
                       96, individual 15 minute, intervals."
              ::= { ds3IntervalEntry 4 }

          ds3IntervalSEFSs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of
                      Severely Errored Framing Seconds, as defined by
                      [12], encountered by a DS3 CSU in one of the
                      previous 96, individual 15 minute, intervals."
              ::= { ds3IntervalEntry 5 }

          ds3IntervalUASs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of
                      Unavailable Seconds, as defined by [12],
                      encountered by a DS3 CSU in one of the previous
                      96, individual 15 minute, intervals."
              ::= { ds3IntervalEntry 6 }

          ds3IntervalCSSs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory



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              DESCRIPTION
                      "The counter associated with the number of
                      Controlled Slip Seconds, as defined by [12],
                      encountered by a DS3 CSU in one of the previous
                      96, individual 15 minute, intervals.

                      Note that SYNTRAN interfaces are the only
                      interfaces that support the Controlled Slip
                      Seconds managed object.  Accordingly, agents
                      configured with non-SYNTRAN interfaces may treat
                      this object as having an ACCESS clause value of
                      not-accessible."
              ::= { ds3IntervalEntry 7}

          ds3IntervalBPVs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of Bipolar
                      Violations, as defined by [12], encountered by a
                      DS3 CSU in one of the previous 96, individual 15
                      minute, intervals."
              ::= { ds3IntervalEntry 8 }

          ds3IntervalCVs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of Coding
                      Violations, as defined by [12], encountered by a
                      DS3 CSU in one of the previous 96, individual 15
                      minute, intervals."
              ::= { ds3IntervalEntry 9 }


          -- the DS3 Current group

          -- Implementation of this group is mandatory for all systems
          -- that attach to a DS3 Interface.

          -- The DS3 current table contains various statistics being
          -- collected for the current 15 minute interval.







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          ds3CurrentTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF DS3CurrentEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION
                      "The DS3 Current table."
              ::= { ds3 3 }

          ds3CurrentEntry OBJECT-TYPE
              SYNTAX  DS3CurrentEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION
                      "An entry in the DS3 Current table."
              INDEX   { ds3CurrentIndex }
              ::= { ds3CurrentTable 1 }

          DS3CurrentEntry ::=
              SEQUENCE {
                  ds3CurrentIndex
                      INTEGER,
                  ds3CurrentESs
                      Counter,
                  ds3CurrentSESs
                      Counter,
                  ds3CurrentSEFSs
                      Counter,
                  ds3CurrentUASs
                      Counter,
                  ds3CurrentCSSs
                      Counter,
                  ds3CurrentBPVs
                      Counter,
                  ds3CurrentCVs
                      Counter
              }

          ds3CurrentIndex OBJECT-TYPE
              SYNTAX  INTEGER
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The index value which uniquely identifies the CSU
                      to which this entry is applicable.  The interface
                      identified by a particular value of this index is
                      the same interface as identified by the same value
                      an DS3CSUIndex object instance."
              ::= { ds3CurrentEntry 1 }



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          ds3CurrentESs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of Errored
                      Seconds, as defined by [12], encountered by a DS3
                      CSU in the current 15 minute interval."
              ::= { ds3CurrentEntry 2 }

          ds3CurrentSESs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of
                      Severely Errored Seconds, as defined by [12],
                      encountered by a DS3 CSU in the current 15 minute
                      interval."
              ::= { ds3CurrentEntry 3 }

          ds3CurrentSEFSs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of
                      Severely Errored Framing Seconds, as defined by
                      [12], encountered by a DS3 CSU in the current 15
                      minute interval."
              ::= { ds3CurrentEntry 4 }

          ds3CurrentUASs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of
                      Unavailable Seconds, as defined by [12],
                      encountered by a DS3 CSU in the current 15 minute
                      interval."
              ::= { ds3CurrentEntry 5 }

          ds3CurrentCSSs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION



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                      "The counter associated with the number of
                      Controlled Slip Seconds, as defined by [12],
                      encountered by a DS3 CSU in the current 15 minute
                      interval.

                      Note that SYNTRAN interfaces are the only
                      interfaces that support the Controlled Slip
                      Seconds managed object.  Accordingly, agents
                      configured with non-SYNTRAN interfaces may treat
                      this object as having an ACCESS clause value of
                      not-accessible."
              ::= { ds3CurrentEntry 6 }

          ds3CurrentBPVs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of Bipolar
                      Violations, as defined by [12], encountered by a
                      DS3 CSU in the current 15 minute interval."
              ::= { ds3CurrentEntry 7}

          ds3CurrentCVs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of Coding
                      Violations, as defined by [12], encountered by a
                      DS3 CSU in the current 15 minute interval."
              ::= { ds3CurrentEntry 8 }


          -- the DS3 Total group

          -- Implementation of this group is mandatory for all systems
          -- that attach to a DS3.

          -- The DS3 Total Table contains the cumulative sum of the
          -- various statistics for the 24 hour interval preceding the
          -- first valid interval in the DS3CurrentTable.

          ds3TotalTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF DS3TotalEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION



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                      "The DS3 Total table.  24 hour interval."
              ::= { ds3 4 }

          ds3TotalEntry OBJECT-TYPE
              SYNTAX  DS3TotalEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION
                      "An entry in the DS3 Total table."
              INDEX   { ds3TotalIndex }
              ::= { ds3TotalTable 1 }

          DS3TotalEntry ::=
              SEQUENCE {
                  ds3TotalIndex
                      INTEGER,
                  ds3TotalESs
                      Counter,
                  ds3TotalSESs
                      Counter,
                  ds3TotalSEFSs
                      Counter,
                  ds3TotalUASs
                      Counter,
                  ds3TotalCSSs
                      Counter,
                  ds3TotalBPVs
                      Counter,
                  ds3TotalCVs
                      Counter
              }

          ds3TotalIndex OBJECT-TYPE
              SYNTAX  INTEGER
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The index value which uniquely identifies the CSU
                      to which this entry is applicable.  The interface
                      identified by a particular value of this index is
                      the same interface as identified by the same value
                      an DS3CSUIndex object instance."
              ::= { ds3TotalEntry 1 }

          ds3TotalESs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory



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              DESCRIPTION
                      "The counter associated with the number of Errored
                      Seconds, as defined by [12], encountered by a DS3
                      CSU in the previous 24 hour interval."
              ::= { ds3TotalEntry 2 }

          ds3TotalSESs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of
                      Severely Errored Seconds, as defined by [12],
                      encountered by a DS3 CSU in the previous 24 hour
                      interval."
              ::= { ds3TotalEntry 3 }

          ds3TotalSEFSs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of
                      Severely Errored Framing Seconds, as defined by
                      [12], encountered by a DS3 CSU in the previous 24
                      hour interval."
              ::= { ds3TotalEntry 4 }

          ds3TotalUASs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of
                      Unavailable Seconds, as defined by [12],
                      encountered by a DS3 CSU in the previous 24 hour
                      interval."
              ::= { ds3TotalEntry 5 }

          ds3TotalCSSs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of
                      Controlled Slip Seconds, as defined by [12],
                      encountered by a DS3 CSU in the previous 24 hour
                      interval.



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RFC 1233                 DS3 Interface Objects                  May 1991


                      Note that SYNTRAN interfaces are the only
                      interfaces that support the Controlled Slip
                      Seconds managed object.  Accordingly, agents
                      configured with non-SYNTRAN interfaces may treat
                      this object as having an ACCESS clause value of
                      not-accessible."
              ::= { ds3TotalEntry 6 }

          ds3TotalBPVs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of Bipolar
                      Violations, as defined by [12], encountered by a
                      DS3 CSU in the previous 24 hour interval."
              ::= { ds3TotalEntry 7 }

          ds3TotalCVs OBJECT-TYPE
              SYNTAX  Counter
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The counter associated with the number of Coding
                      Violations, as defined by [12], encountered by a
                      DS3 CSU in the previous 24 hour interval."
              ::= { ds3TotalEntry 8 }



          END

6.  Acknowledgments

   This document was produced by the SNMP and the Transmission MIB
   Working Groups:

               Anne Ambler, Spider
               Karl Auerbach, Sun
               Fred Baker, ACC
               Ken Brinkerhoff
               Ron Broersma, NOSC
               Jack Brown, US Army
               Theodore Brunner, Bellcore
               Jeffrey Buffum, HP
               Jeffrey D. Case, UTK
               Chris Chiptasso, Spartacus
               Paul Ciarfella, DEC



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RFC 1233                 DS3 Interface Objects                  May 1991


               Bob Collet
               Tracy Cox, Bellcore
               James R. Davin, MIT-LCS
               Kurt Dobbins, Cabletron
               Nadya El-Afandi, Network Systems
               Gary Ellis, HP
               Fred Engle
               Mike Erlinger
               Richard Fox, Synoptics
               Karen Frisa, CMU
               Chris Gunner, DEC
               Ken Hibbard, Xylogics
               Ole Jacobsen, Interop
               Ken Jones
               Satish Joshi, Synoptics
               Frank Kastenholz, Racal-Interlan
               Shimshon Kaufman, Spartacus
               Jim Kinder, Fibercom
               Alex Koifman, BBN
               Christopher Kolb, PSI
               Cheryl Krupczak, NCR
               Peter Lin, Vitalink
               John Lunny, TWG
               Carl Malamud
               Keith McCloghrie, HLS
               Donna McMaster, David Systems
               Lynn Monsanto, Sun
               Dave Perkins, 3COM
               Jim Reinstedler, Ungerman Bass
               Anil Rijsinghani, DEC
               Kary Robertson
               Marshall T. Rose, PSI (chair)
               L. Michael Sabo, NCSC
               Jon Saperia, DEC
               John Seligson
               Fei Shu, NEC
               Sam Sjogren, TGV
               Mark Sleeper, Sparta
               Lance Sprung
               Mike St.Johns
               Bob Stewart, Xyplex
               Emil Sturniold
               Kaj Tesink, Bellcore
               Dean Throop, Data General
               Bill Townsend, Xylogics
               Maurice Turcotte
               Kannan Varadhou
               Sudhanshu Verma, HP



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RFC 1233                 DS3 Interface Objects                  May 1991


               Warren Vik, Interactive Systems
               David Waitzman, BBN
               Steve Waldbusser, CMU
               Dan Wintringhan
               David Wood
               Jeff Young, Cray Research

7.  References

   [1] Cerf, V., "IAB Recommendations for the Development of Internet
       Network Management Standards", RFC 1052, NRI, April 1988.

   [2] Cerf, V., "Report of the Second Ad Hoc Network Management Review
       Group", RFC 1109, NRI, August 1989.

   [3] Rose M., and K. McCloghrie, "Structure and Identification of
       Management Information for TCP/IP-based internets", RFC 1155,
       Performance Systems International, Hughes LAN Systems, May 1990.

   [4] McCloghrie K., and M. Rose, "Management Information Base for
       Network Management of TCP/IP-based internets", RFC 1156, Hughes
       LAN Systems, Performance Systems International, May 1990.

   [5] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple
       Network Management Protocol", RFC 1157, SNMP Research,
       Performance Systems International, Performance Systems
       International, MIT Laboratory for Computer Science, May 1990.

   [6] McCloghrie K., and M. Rose, Editors, "Management Information Base
       for Network Management of TCP/IP-based internets", RFC 1213,
       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 - electrical interfaces, ANSI T1.102- 1987.

  [10] American National Standard for telecommunications - digital
       hierarchy - formats specification, ANSI T1.107- 1988.




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RFC 1233                 DS3 Interface Objects                  May 1991


  [10a] ANSI T1.107a-1989.

  [11] American National Standard for telecommunications - Carrier-to-
       Customer Installation - DS3 Metallic Interface, ANSI T1.404-1989.

  [12] In-Service Digital Transmission Performance Monitoring Draft
       Standard, T1M1.3/90 - 027R2.

  [13] Rose, M., and K. McCloghrie, Editors, "Concise MIB Definitions",
       RFC 1212, Performance Systems International, Hughes LAN Systems,
       March 1991.

8.  Security Considerations

   Security issues are not discussed in this memo.

9.  Authors' Addresses

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

   Phone: (908) 758-2107

   EMail: tacox@sabre.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@nvuxr.cc.bellcore.com













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