[Docs] [txt|pdf] [draft-ietf-trunkm...] [Diff1] [Diff2]

Obsoleted by: 2495 PROPOSED STANDARD

Network Working Group                                           F. Baker
Request for Comments: 1406              Advanced Computer Communications
Obsoletes: 1232                                                  J. Watt
                                          Newbridge Networks Corporation
                                                                 Editors
                                                            January 1993


   Definitions of Managed Objects for the DS1 and E1 Interface Types

Status of this Memo

   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.

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 DS1 Interfaces --
   including both T1 and E1 (a.k.a., CEPT 2 Mbit/s) links.

   This document entirely replaces RFC 1232, which contains a
   fundamental error: many objects are encoded as Counters that must be
   encoded as INTEGERs or Gauges.  The magnitude of the change required
   is sufficient that virtually every object changed.  Therefore, the
   MIB documented in RFC 1232 should not be implemented.

Table of Contents

   1. The Network Management Framework ......................    2
   2. Objects ...............................................    2
   2.1 Format of Definitions ................................    3
   2.2 Changes from RFC 1232 ................................    3
   3. Overview ..............................................    4
   3.1 Binding between ifIndex and DS1 Interfaces ...........    5
   3.2 Objectives of this MIB Module ........................    7
   3.3 DS1 Terminology ......................................    7
   3.3.1 Error Events .......................................    7
   3.3.2 Performance Defects ................................    8
   3.3.3 Performance Parameters .............................    9
   3.3.4 Failure States .....................................   11
   3.3.5 Other Terms ........................................   13
   4. Definitions ...........................................   14
   4.1 DS1 Near End Group ...................................   14



Trunk MIB Working Group                                         [Page 1]

RFC 1406                       DS1/E1 MIB                   January 1993


   4.1.1 DS1 Configuration Table ............................   14
   4.1.2 DS1 Current Table ..................................   22
   4.1.3 DS1 Interval Table .................................   26
   4.1.4 DS1 Total Table ....................................   30
   4.2 DS1 Far End Group ....................................   33
   4.2.1 DS1 Far End Current Table ..........................   34
   4.2.2 DS1 Far End Interval Table .........................   38
   4.2.3 DS1 Far End Total Table ............................   41
   4.3 DS1 Fractional Group .................................   45
   4.3.1 DS1 Fractional Table ...............................   45
   5. Acknowledgements ......................................   47
   6. References ............................................   48
   7. Security Considerations ...............................   50
   8. Authors' Addresses ....................................   50

1.  The Network Management Framework

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

      STD 16/RFC 1155 [1] which defines the SMI, the mechanisms used for
      describing and naming objects for the purpose of management.  STD
      16/RFC 1212 [2] defines a more concise description mechanism,
      which is wholly consistent with the SMI.

      RFC 1156 [3] which defines MIB-I, the core set of managed objects
      for the Internet suite of protocols.  STD 17/RFC 1213 [4] defines
      MIB-II, an evolution of MIB-I based on implementation experience
      and new operational requirements.

      STD 15/RFC 1157 [5] 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.

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) [6]
   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.



Trunk MIB Working Group                                         [Page 2]

RFC 1406                       DS1/E1 MIB                   January 1993


   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 [1] 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 [7],
   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 STD 16, RFC 1212 [2].

2.2.  Changes from RFC 1232

   The changes from RFC 1232 are the following:

     (1)  This MIB module contains three groups: DS1 Near End Group
          which is mandatory, DS1 Far End Group which is optional,
          and the Fractional Table, which is optional.

     (2)  The Far End Group is a new group and contains statistics
          that are collected from the far end DS1 interface.  The
          Far End Group may only be implemented by DS1 systems that
          use the facilities data link to exchange this information
          - both T1.403 and PUB 54016 define ways to exchange this
          information over data links; vendors may use other
          proprietary means to do this on various link types.

     (3)  ds1CSUIndex has been renamed dsx1LineIndex.  This object
          is the identifier of a DS1 Interface on a device.  On a
          CSU, a single DS1 data stream will cross two DS1
          interfaces, which have separate dsx1LineIndex values.

     (4)  ds1Index has been renamed dsx1IfIndex.  This value for
          this object is equal to the value of ifIndex from the
          Interfaces table of MIB II (STD 17, RFC 1213).

     (5)  an object has been added (dsx1TransmitClockSource) to
          indicate the source of transmit clock.



Trunk MIB Working Group                                         [Page 3]

RFC 1406                       DS1/E1 MIB                   January 1993


     (6)  The ACCESS for objects in the dsx1ConfigTable has been
          set to read-write for items that are configurable.

     (7)  Description of test configurations has changed.  A new
          object has been added called dsx1LoopbackConfig, which
          better describes the loopback capabilities of a DS1
          interface on a device.

     (8)  The description of line alarm status has changed.  A new
          object has been added called dsx1LineStatus.  This object
          better describes the status (e.g., failure state and
          loopback state) of a DS1 interface.

     (9)  All Counters have been changed to Gauges.

     (10) Information about how applications might use the zero
          code suppression have been removed; only the actual line
          coding algorithm is described.  For clarity the object
          was thus renamed to dsx1LineCoding.

     (11) A Line Errored Seconds object has been added to all near
          end tables and the count of Bipolar Violations (BPVs) was
          changed to a count of Line Code Violations (LCVs).

     (12) Bursty Errored Seconds (a.k.a., Errored Seconds Type B)
          and Degraded Minutes objects have been added to all near
          end tables.

     (13) The Coding Violation error event is now referred to as a
          Path Coding Violation (PCV) Error Event.

3.  Overview

   These objects are used when the particular media being used to
   realize an interface is a DS1 physical interface.  At present, this
   applies to these values of the ifType variable in the Internet-
   standard MIB:

            ds1 (18)
            e1  (19)

   The definitions contained herein are based on the AT&T T-1 Superframe
   (a.k.a., D4) and Extended Superframe (ESF) formats [8, 9], the latter
   of which conforms to ANSI specifications [10], and the CCITT
   Recommendations [11, 12], referred to as E1 for the rest of this
   memo.





Trunk MIB Working Group                                         [Page 4]

RFC 1406                       DS1/E1 MIB                   January 1993


   The various T1 and E1 line disciplines are similar enough that
   separate MIBs are unwarranted, although there are some differences.
   For example, Loss of Frame is defined more rigorously in the ESF
   specification than in the D4 specification, but it is defined in
   both.

   Where it is necessary to distinguish between the flavors of E1 with
   and without CRC, E1-CRC to denotes the "with CRC" form (G.704 Table
   4b) and E1-noCRC denotes the "without CRC" form (G.704 Table 4a).

3.1.  Binding between ifIndex and DS1 Interfaces

   Different physical configurations for the support of SNMP with DS1
   equipment exist. To accommodate these scenarios, two different
   indices for DS1 interfaces are introduced in this MIB.  These indices
   are dsx1IfIndex and dsx1LineIndex.

   External interface scenario: the SNMP Agent represents all managed
   DS1 lines as external interfaces (for example, an Agent residing on
   the device supporting DS1 interfaces directly):

   For this scenario, all interfaces are assigned an integer value equal
   to ifIndex, and the following applies:

         ifIndex=dsx1IfIndex=dsx1LineIndex for all interfaces.

   The dsx1IfIndex column of the DS1 Configuration table relates each
   DS1 interface to its corresponding interface (ifIndex) in the
   Internet-standard MIB (MIB-II STD 17, RFC 1213).

   External & Internal interface scenario: the SNMP Agents resides on an
   host external from the device supporting DS1 interfaces (e.g., a
   router).  The Agent represents both the host and the DS1 device.  The
   index dsx1LineIndex is used to not only represent the DS1 interfaces
   external from the host/DS1-device combination, but also the DS1
   interfaces connecting the host and the DS1 device.  The index
   dsx1IfIndex is always equal to ifIndex.

   Example:

   A shelf full of CSUs connected to a Router.  An SNMP Agent residing
   on the router proxies for itself and the CSU.  The router has also an
   Ethernet interface:








Trunk MIB Working Group                                         [Page 5]

RFC 1406                       DS1/E1 MIB                   January 1993


           +-----+
     |     |     |
     |     |     |               +---------------------+
     |E    |     |  1.544  MBPS  |              Line#A | DS1 Link
     |t    |  R  |---------------+ - - - - -  - - -  - +------>
     |h    |     |               |                     |
     |e    |  O  |  1.544  MBPS  |              Line#B | DS1 Link
     |r    |     |---------------+ - - - - - - - - - - +------>
     |n    |  U  |               |  CSU Shelf          |
     |e    |     |  1.544  MBPS  |              Line#C | DS1 Link
     |t    |  T  |---------------+ - - - -- -- - - - - +------>
     |     |     |               |                     |
     |-----|  E  |  1.544  MBPS  |              Line#D | DS1 Link
     |     |     |---------------+ -  - - - -- - - - - +------>
     |     |  R  |               |_____________________|
     |     |     |
     |     +-----+

     The assignment of the index values could for example be:

     ifIndex (= dsx1IfIndex)             dsx1LineIndex
     1                   NA                  NA (Ethernet)
     2      Line#A   Router Side             6
     2      Line#A   Network Side            7
     3      Line#B   Router Side             8
     3      Line#B   Network Side            9
     4      Line#C   Router Side            10
     4      Line#C   Network Side           11
     5      Line#D   Router Side            12
     5      Line#D   Network Side           13

   For this example, ifNumber is equal to 5.  Note the following
   description of dsx1LineIndex: the dsx1LineIndex identifies a DS1
   Interface on a managed device.  If there is an ifEntry that is
   directly associated with this and only this DS1 interface, it should
   have the same value as ifIndex.  Otherwise, number the
   dsx1LineIndices with an unique identifier following the rules of
   choosing a number greater than ifNumber and numbering inside
   interfaces (e.g., equipment side) with even numbers and outside
   interfaces (e.g., network side) with odd numbers.

   If the CSU shelf is managed by itself by a local SNMP Agent, the
   situation would be:








Trunk MIB Working Group                                         [Page 6]

RFC 1406                       DS1/E1 MIB                   January 1993


          ifIndex (= dsx1IfIndex)               dsx1LineIndex
          2      Line#A     Router Side             2
          1      Line#A     Network Side            1
          4      Line#B     Router Side             4
          3      Line#B     Network Side            3
          6      Line#C     Router Side             6
          5      Line#C     Network Side            5
          8      Line#D     Router Side             8
          7      Line#D     Network Side            7

3.2.  Objectives of this MIB Module

   There are numerous things that could be included in a MIB for DS1
   signals: the management of multiplexors, CSUs, DSUs, and the like.
   The intent of this document is to facilitate the common management of
   all devices with DS1 interfaces.  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 DS1 devices that are currently deployed.

3.3.  DS1 Terminology

   The terminology used in this document to describe error conditions on
   a DS1 interface as monitored by a DS1 device are based on the
   definitions from the ANSI T1M1.3/92-005R1 draft standard [13].  If
   the definition in this document does not match the definition in the
   ANSI T1M1.3/92-005R1 draft document, the implementer should follow
   the definition described in this document.

3.3.1.  Error Events

     Bipolar Violation (BPV) Error Event
          A BPV error event for an AMI-coded signal is the
          occurrence of a pulse of the same polarity as the
          previous pulse.  A BPV error event for a B8ZS- or HDB3-
          coded signal is the occurrence of a pulse of the same
          polarity as the previous pulse without being a part of
          the zero substitution code.

     Excessive Zeroes (EXZ) Error Event
          An Excessive Zeroes error event for an AMI-coded signal
          is the occurrence of more than fifteen contiguous zeroes.
          For a B8ZS coded signal, the defect occurs when more than
          seven contiguous zeroes are detected.

     Line Coding Violation (LCV) Error Event
          A Line Coding Violation (LCV) is the occurrence of either
          a Bipolar Violation (BPV) or Excessive Zeroes (EXZ) Error
          Event.



Trunk MIB Working Group                                         [Page 7]

RFC 1406                       DS1/E1 MIB                   January 1993


     Path Coding Violation (PCV) Error Event
          A Path Coding Violation error event is a frame
          synchronization bit error in the D4 and E1-noCRC formats,
          or a CRC error in the ESF and E1-CRC formats.

     Controlled Slip (CS) Error Event
          A Controlled Slip is the replication or deletion of the
          payload bits of a DS1 frame.  A Controlled Slip  may be
          performed when there is a difference between the timing
          of a synchronous receiving terminal and the received
          signal.  A Controlled Slip does not cause an Out of Frame
          defect.

3.3.2.  Performance Defects

     Out Of Frame (OOF) Defect
          An OOF defect is the occurrence of a particular density
          of Framing Error events.

          For T1 links, an Out of Frame defect is declared when the
          receiver detects two or more framing errors within a 3
          msec period for ESF signals and 0.75 msec for D4 signals,
          or two or more errors out of five or fewer consecutive
          framing-bits.

          For E1 links, an Out Of Frame defect is declared when
          three consecutive frame alignment signals have been
          received with an error (see G.706 Section 4.1 [17]).

          Once an Out Of Frame Defect is declared, the framer
          starts searching for a correct framing pattern.  The Out
          of Frame defect ends when the signal is in frame.

          In-frame occurs when there are fewer than two frame bit
          errors within 3 msec period for ESF signals and 0.75 msec
          for D4 signals.

          For E1 links, in-frame occurs when a) in frame N the
          frame alignment signal is correct and b) in frame N+1 the
          frame alignment signal is absent (i.e., bit 2 in TS0 is a
          one) and c) in frame N+2 the frame alignment signal is
          present and correct.

     Alarm Indication Signal (AIS) Defect
          For D4 and ESF links, the 'all ones' condition is
          detected at a DS1 line interface upon observing an
          unframed signal with a one's density of at least 99.9%
          present for a time equal to or greater than T, where 3 ms



Trunk MIB Working Group                                         [Page 8]

RFC 1406                       DS1/E1 MIB                   January 1993


          <= T <= 75 ms.  The AIS is terminated upon observing a
          signal not meeting the one's density or the unframed
          signal criteria for a period equal to or greater than
          than T.

          For E1 links, the 'all-ones' condition is detected at the
          line interface as a string of 512 bits containing fewer
          than three zero bits (see O.162 [14] Section 3.3.2).

3.3.3.  Performance Parameters

   All performance parameters are accumulated in fifteen minute
   intervals and up to 96 intervals (24 hours worth) are kept by an
   agent.  Fewer than 96 intervals of data will be available if the
   agent has been restarted within the last 24 hours.  In addition,
   there is a rolling 24-hour total of each performance parameter.

   There is no requirement for an agent to ensure fixed relationship
   between the start of a fifteen minute interval and any wall clock;
   however some agents may align the fifteen minute intervals with
   quarter hours.

     Line Errored Seconds (LES)
          A Line Errored Second, according to T1M1.3, is a second
          in which one or more Line Code Violation error events
          were detected.

          While many implementations are currently unable to detect
          the zero strings, it is expected that interface
          manufacturers will add this capability in deference to
          ANSI; therefore, it will become available in time.

          In the T1M1.3 specification, near end Line Code
          Violations and far end Line Errored Seconds are counted.
          For consistency, we count Line Errored Seconds at both
          ends.

     Controlled Slip Seconds (CSS)
          A Controlled Slip Second is a one-second interval
          containing one or more controlled slips.

     Errored Seconds (ES)
          For ESF and E1-CRC links an Errored Second is a second
          with one or more Path Code Violations OR one or more Out
          of Frame defects OR one or more Controlled Slip events OR
          a detected AIS defect.

          For D4 and E1-noCRC links, the presence of Bipolar



Trunk MIB Working Group                                         [Page 9]

RFC 1406                       DS1/E1 MIB                   January 1993


          Violations also triggers an Errored Second.

          This is not incremented during an Unavailable Second.

     Bursty Errored Seconds (BES)
          A Bursty Errored Second (also known as Errored Second
          type B) is a second with fewer than 320 and more than 1
          Path Coding Violation error events, no Severely Errored
          Frame defects and no detected incoming AIS defects.
          Controlled slips are not included in this parameter.

          This is not incremented during an Unavailable Second.

     Severely Errored Seconds (SES)
          A Severely Errored Second for ESF signals is a second
          with 320 or more Path Code Violation Error Events OR one
          or more Out of Frame defects OR a detected AIS defect.

          For E1-CRC signals, a Severely Errored Second is a second
          with 832 or more Path Code Violation error events OR one
          or more Out of Frame defects.

          For E1-noCRC signals, a Severely Errored Second is a 2048
          LCVs or more.

          For D4 signals, a Severely Errored Second is a count of
          one-second intervals with Framing Error events, or an OOF
          defect, or 1544 LCVs or more.

          Controlled slips are not included in this parameter.

          This is not incremented during an Unavailable Second.

     Severely Errored Framing Second (SEFS)
          An Severely Errored Framing Second is a second with one
          or more Out of Frame defects OR a detected AIS defect.

     Degraded Minutes
          A Degraded Minute is one in which the estimated error
          rate exceeds 1E-6 but does not exceed 1E-3 (see G.821
          [15]).

          Degraded Minutes are determined by collecting all of the
          Available Seconds, removing any Severely Errored Seconds
          grouping the result in 60-second long groups and counting
          a 60-second long group (a.k.a., minute) as degraded if the
          cumulative errors during the seconds present in the group
          exceed 1E-6.  Available seconds are merely those seconds



Trunk MIB Working Group                                        [Page 10]

RFC 1406                       DS1/E1 MIB                   January 1993


          which are not Unavailable as described below.

     Unavailable Seconds (UAS)
          Unavailable Seconds (UAS) are calculated by counting the
          number of seconds that the interface is unavailable.  The
          DS1 interface is said to be unavailable from the onset of
          10 contiguous SESs, or the onset of the condition leading
          to a failure (see Failure States).  If the condition
          leading to the failure was immediately preceded by one or
          more contiguous SESs, then the DS1 interface
          unavailability starts from the onset of these SESs.  Once
          unavailable, and if no failure is present, the DS1
          interface becomes available at the onset of 10 contiguous
          seconds with no SESs.  Once unavailable, and if a failure
          is present, the DS1 interface becomes available at the
          onset of 10 contiguous seconds with no SESs, if the
          failure clearing time is less than or equal to 10
          seconds.  If the failure clearing time is more than 10
          seconds, the DS1 interface becomes available at the onset
          of 10 contiguous seconds with no SESs, or the onset
          period leading to the successful clearing condition,
          whichever occurs later.  With respect to the DS1 error
          counts, all counters are incremented while the DS1
          interface is deemed available.  While the interface is
          deemed unavailable, the only count that is incremented is
          UASs.

          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 Severely Errored
          Second and Unavailable Second counters must be adjusted
          when the Unavailable Signal State is entered.  Clearly,
          successive GETs of the affected dsx1IntervalSESs and
          dsx1IntervalUASs 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.

3.3.4.  Failure States

   The following failure states are received, or detected failures, that
   are reported in the dsx1LineStatus object.  When a DS1 interface
   would, if ever, produce the conditions leading to the failure state
   is described in the appropriate specification.






Trunk MIB Working Group                                        [Page 11]

RFC 1406                       DS1/E1 MIB                   January 1993


     Far End Alarm Failure
          The Far End Alarm failure is also known as "Yellow Alarm"
          in the T1 case and "Distant Alarm" in the E1 case.

          For D4 links, the Far End Alarm failure is declared when
          bit 6 of all channels has been zero for at least 335 ms
          and is cleared when bit 6 of at least one channel is
          non-zero for a period T, where T is usually less than one
          second and always less than 5 seconds.  The Far End Alarm
          failure is not declared for D4 links when a Loss of
          Signal is detected.

          For ESF links, the Far End Alarm failure is declared if
          the Yellow Alarm signal pattern occurs in at least seven
          out of ten contiguous 16-bit pattern intervals and is
          cleared if the Yellow Alarm signal pattern does not occur
          in ten contiguous 16-bit signal pattern intervals.

          For E1 links, the Far End Alarm failure is declared when
          bit 3 of time-slot zero is received set to one on two
          consecutive occasions.  The Far End Alarm failure is
          cleared when bit 3 of time-slot zero is received set to
          zero.

     Alarm Indication Signal (AIS) Failure
          The Alarm Indication Signal failure is declared when an
          AIS defect is detected at the input and the  AIS defect
          still exists after the Loss Of Frame failure (which is
          caused by the unframed nature of the 'all-ones' signal)
          is declared. The AIS failure is cleared when the Loss Of
          Frame failure is cleared.

     Loss Of Frame Failure
          For T1 links, the Loss Of Frame failure is declared when
          an OOF or LOS  defect has persisted for T seconds, where
          2 <= T <= 10.  The Loss Of Frame failure is cleared when
          there have been no OOF or LOS defects during a period T
          where 0 <= T <= 20.  Many systems will perform "hit
          integration" within the period T before declaring or
          clearing the failure e.g., see TR 62411 [16].

          For E1 links, the Loss Of Frame Failure is declared when
          an OOF defect is detected.

     Loss Of Signal Failure
          For T1, the Loss Of Signal failure is declared upon
          observing 175 +/- 75 contiguous pulse positions with no
          pulses of either positive or negative polarity.  The LOS



Trunk MIB Working Group                                        [Page 12]

RFC 1406                       DS1/E1 MIB                   January 1993


          failure is cleared upon observing an average pulse
          density of at least 12.5% over a period of 175 +/- 75
          contiguous pulse positions starting with the receipt of a
          pulse.

          For E1 links, the Loss Of Signal failure is declared when
          greater than 10 consecutive zeroes are detected (see
          O.162 Section 3.4.4).

     Loopback Pseudo-Failure
          The Loopback Pseudo-Failure is declared when the near end
          equipment has placed a loopback (of any kind) on the DS1.
          This allows a management entity to determine from one
          object whether the DS1 can be considered to be in service
          or not (from the point of view of the near end
          equipment).

     TS16 Alarm Indication Signal Failure
          For E1 links, the TS16 Alarm Indication Signal failure is
          declared when time-slot 16 is received as all ones for
          all frames of two consecutive multiframes (see G.732
          Section 4.2.6).  This condition is never declared for T1.

     Loss Of MultiFrame Failure
          The Loss Of MultiFrame failure is declared when two
          consecutive multiframe alignment signals (bits 4 through
          7 of TS16 of frame 0) have been received with an error.
          The Loss Of Multiframe failure is cleared when the first
          correct multiframe alignment signal is received.  The
          Loss Of Multiframe failure can only be declared for E1
          links operating with G.732 [18] framing (sometimes called
          "Channel Associated Signalling" mode).

     Far End Loss Of Multiframe Failure
          The Far End Loss Of Multiframe failure is declared when
          bit 2 of TS16 of frame 0 is received set to one on two
          consecutive occasions.  The Far End Loss Of Multiframe
          failure is cleared when bit 2 of TS16 of frame 0 is
          received set to zero.  The Far End Loss Of Multiframe
          failure can only be declared for E1 links operating in
          "Channel Associated Signalling" mode.

3.3.5.  Other Terms

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



Trunk MIB Working Group                                        [Page 13]

RFC 1406                       DS1/E1 MIB                   January 1993


4.  Definitions

     RFC1406-MIB DEFINITIONS ::= BEGIN
     IMPORTS
             Gauge
                     FROM RFC1155-SMI
             transmission, DisplayString
                     FROM RFC1213-MIB
             OBJECT-TYPE
                     FROM RFC-1212;

     --  This MIB module uses the extended OBJECT-TYPE macro as
     --  defined in RFC 1212.

     --  this is the MIB module for the DS1 objects

     ds1 OBJECT IDENTIFIER ::= { transmission 18 }

     -- note that this subsumes cept (19); there is no separate CEPT MIB


     -- The DS1 Near End Group

     -- Implementation of this group is mandatory for all systems
     -- that attach to a DS1 Interface.

     -- The DS1 Near End Group consists of four tables:
     --    DS1 Configuration
     --    DS1 Current
     --    DS1 Interval
     --    DS1 Total

     -- the DS1 Configuration Table

         dsx1ConfigTable OBJECT-TYPE
             SYNTAX  SEQUENCE OF Dsx1ConfigEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "The DS1 Configuration table."
            ::= { ds1 6 }


         dsx1ConfigEntry OBJECT-TYPE
             SYNTAX  Dsx1ConfigEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION



Trunk MIB Working Group                                        [Page 14]

RFC 1406                       DS1/E1 MIB                   January 1993


                "An entry in the DS1 Configuration table."
            INDEX   { dsx1LineIndex }
            ::= { dsx1ConfigTable 1 }

     Dsx1ConfigEntry ::=
         SEQUENCE {
             dsx1LineIndex
                 INTEGER,
             dsx1IfIndex
                 INTEGER,
             dsx1TimeElapsed
                 INTEGER,
             dsx1ValidIntervals
                 INTEGER,
             dsx1LineType
                 INTEGER,
             dsx1LineCoding
                 INTEGER,
             dsx1SendCode
                 INTEGER,
             dsx1CircuitIdentifier
                 DisplayString,
             dsx1LoopbackConfig
                 INTEGER,
             dsx1LineStatus
                 INTEGER,
             dsx1SignalMode
                 INTEGER,
             dsx1TransmitClockSource
                 INTEGER,
             dsx1Fdl
                 INTEGER
         }

         dsx1LineIndex OBJECT-TYPE
             SYNTAX  INTEGER (1..'7fffffff'h)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "This object is the identifier of a DS1  Inter-
                face on a managed device.  If there is an ifEn-
                try that is directly associated with  this  and
                only  this  DS1  interface,  it should have the
                same value as ifIndex.   Otherwise,  the  value
                exceeds  ifNumber,  and  is a unique identifier
                following this rule: inside  interfaces  (e.g.,
                equipment  side)  with even numbers and outside
                interfaces  (e.g.,  network   side)   with   odd



Trunk MIB Working Group                                        [Page 15]

RFC 1406                       DS1/E1 MIB                   January 1993


                numbers."
            ::= { dsx1ConfigEntry 1 }


         dsx1IfIndex OBJECT-TYPE
             SYNTAX  INTEGER (1..'7fffffff'h)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "This value for this object  is  equal  to  the
                value  of  ifIndex from the Interfaces table of
                MIB II (RFC 1213)."
            ::= { dsx1ConfigEntry 2 }


         dsx1TimeElapsed OBJECT-TYPE
             SYNTAX  INTEGER (0..899)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of seconds that have elapsed  since
                the  beginning of the current error-measurement
                period."
            ::= { dsx1ConfigEntry 3 }


         dsx1ValidIntervals 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 the interface was brought on-line within
                the last 24 hours, in which case the value will
                be the number of complete 15  minute  intervals
                the since interface has been online."
            ::= { dsx1ConfigEntry 4 }


         dsx1LineType OBJECT-TYPE
             SYNTAX  INTEGER {
                         other(1),
                         dsx1ESF(2),
                         dsx1D4(3),
                         dsx1E1(4),
                         dsx1E1-CRC(5),
                         dsx1E1-MF(6),



Trunk MIB Working Group                                        [Page 16]

RFC 1406                       DS1/E1 MIB                   January 1993


                         dsx1E1-CRC-MF(7)
                     }
             ACCESS  read-write
             STATUS  mandatory
             DESCRIPTION
                "This variable indicates  the  variety  of  DS1
                Line  implementing  this  circuit.  The type of
                circuit affects the number of bits  per  second
                that  the circuit can reasonably carry, as well
                as the interpretation of the  usage  and  error
                statistics.  The values, in sequence, describe:

                TITLE:        SPECIFICATION:
                dsx1ESF       Extended SuperFrame DS1
                dsx1D4        AT&T D4 format DS1
                dsx1E1        CCITT Recommendation G.704
                                (Table 4a)
                dsx1E1-CRC    CCITT Recommendation G.704
                                (Table 4b)
                dsxE1-MF      G.704 (Table 4a) with TS16
                                multiframing enabled
                dsx1E1-CRC-MF G.704 (Table 4b) with TS16
                                multiframing enabled"

                    ::= { dsx1ConfigEntry 5 }


         dsx1LineCoding OBJECT-TYPE
             SYNTAX  INTEGER {
                         dsx1JBZS (1),
                         dsx1B8ZS (2),
                         dsx1HDB3 (3),
                         dsx1ZBTSI (4),
                         dsx1AMI (5),
                         other(6)
                     }
             ACCESS  read-write
             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.

                dsx1JBZS refers the Jammed  Bit  Zero  Suppres-
                sion,  in  which  the  AT&T specification of at
                least one pulse every 8 bit periods is literal-
                ly  implemented  by forcing a pulse in bit 8 of
                each channel.  Thus, only seven bits per  chan-



Trunk MIB Working Group                                        [Page 17]

RFC 1406                       DS1/E1 MIB                   January 1993


                nel, or 1.344 Mbps, is available for data.

                dsx1B8ZS refers to the use of a specified  pat-
                tern  of  normal  bits  and  bipolar violations
                which are used to replace a sequence  of  eight
                zero bits.

                ANSI Clear Channels may use dsx1ZBTSI, or  Zero
                Byte Time Slot Interchange.

                E1 links, with or without CRC, use dsx1HDB3  or
                dsx1AMI.

                dsx1AMI refers to a mode wherein no  zero  code
                suppression  is  present  and the line encoding
                does not solve the problem directly.   In  this
                application, the higher layer must provide data
                which meets or exceeds the  pulse  density  re-
                quirements, such as inverting HDLC data."
            ::= { dsx1ConfigEntry 6 }


         dsx1SendCode OBJECT-TYPE
             SYNTAX  INTEGER {
                         dsx1SendNoCode(1),
                         dsx1SendLineCode(2),
                         dsx1SendPayloadCode(3),
                         dsx1SendResetCode(4),
                         dsx1SendQRS(5),
                         dsx1Send511Pattern(6),
                         dsx1Send3in24Pattern(7),
                         dsx1SendOtherTestPattern(8)
                     }
             ACCESS  read-write
             STATUS  mandatory
             DESCRIPTION
                "This variable indicates what type of  code  is
                being sent across the DS1 interface by the dev-
                ice.  The values mean:

                dsx1SendNoCode
                     sending looped or normal data

                dsx1SendLineCode
                     sending a request for a line loopback

                dsx1SendPayloadCode
                     sending a request for a payload loopback



Trunk MIB Working Group                                        [Page 18]

RFC 1406                       DS1/E1 MIB                   January 1993


                dsx1SendResetCode
                     sending a loopback termination request

                dsx1SendQRS
                     sending a Quasi-Random Signal  (QRS)  test
                     pattern

                dsx1Send511Pattern
                     sending a 511 bit fixed test pattern

                dsx1Send3in24Pattern
                     sending a fixed test pattern of 3 bits set
                     in 24

                dsx1SendOtherTestPattern
                     sending a test pattern  other  than  those
                     described by this object"
            ::= { dsx1ConfigEntry 7 }


         dsx1CircuitIdentifier OBJECT-TYPE
             SYNTAX  DisplayString (SIZE (0..255))
             ACCESS  read-write
             STATUS  mandatory
             DESCRIPTION
                "This  variable   contains   the   transmission
                vendor's circuit identifier, for the purpose of
                facilitating troubleshooting."
            ::= { dsx1ConfigEntry 8 }


         dsx1LoopbackConfig OBJECT-TYPE
             SYNTAX  INTEGER {
                         dsx1NoLoop(1),
                         dsx1PayloadLoop(2),
                         dsx1LineLoop(3),
                         dsx1OtherLoop(4)
                     }
             ACCESS  read-write
             STATUS  mandatory
             DESCRIPTION
                "This variable represents the  loopback  confi-
                guration of the DS1 interface.  Agents support-
                ing read/write access should return badValue in
                response to a requested loopback state that the
                interface does not support.  The values mean:





Trunk MIB Working Group                                        [Page 19]

RFC 1406                       DS1/E1 MIB                   January 1993


                dsx1NoLoop
                     Not in the loopback state.  A device  that
                     is not capable of performing a loopback on
                     the interface shall always return this  as
                     it's value.

                dsx1PayloadLoop
                     The received signal at this  interface  is
                     looped  through  the device. Typically the
                     received signal is  looped  back  for  re-
                     transmission  after  it has passed through
                     the device's framing function.

                dsx1LineLoop
                     The received signal at this interface does
                     not  go  through the device (minimum pene-
                     tration) but is looped back out.

                dsx1OtherLoop
                     Loopbacks that are not defined here."
            ::= { dsx1ConfigEntry 9 }


         dsx1LineStatus OBJECT-TYPE
             SYNTAX  INTEGER (1..8191)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "This variable indicates the Line Status of the
                interface.   It contains loopback, failure, re-
                ceived 'alarm'  and transmitted 'alarm'  infor-
                mation.

     The dsx1LineStatus is a bit  map  represented  as  a  sum,
     therefore, it can represent multiple failures (alarms) and
     a LoopbackState simultaneously.

     dsx1NoAlarm should be set if and only if no other flag  is
     set.

     If the dsx1LoopbackState bit is set, the loopback  in  ef-
     fect can be determined from the dsx1LoopbackConfig object.

     The various bit positions are:
          1     dsx1NoAlarm           No Alarm Present
          2     dsx1RcvFarEndLOF      Far end LOF (a.k.a., Yellow Alarm)
          4     dsx1XmtFarEndLOF      Near end sending LOF Indication
          8     dsx1RcvAIS            Far end sending AIS



Trunk MIB Working Group                                        [Page 20]

RFC 1406                       DS1/E1 MIB                   January 1993


         16     dsx1XmtAIS            Near end sending AIS
         32     dsx1LossOfFrame       Near end LOF (a.k.a., Red Alarm)
         64     dsx1LossOfSignal      Near end Loss Of Signal
        128     dsx1LoopbackState     Near end is looped
        256     dsx1T16AIS            E1 TS16 AIS
        512     dsx1RcvFarEndLOMF     Far End Sending TS16 LOMF
       1024     dsx1XmtFarEndLOMF     Near End Sending TS16 LOMF
       2048     dsx1RcvTestCode       Near End detects a test code
       4096     dsx1OtherFailure      any line status not defined here"
         ::= { dsx1ConfigEntry 10 }


         dsx1SignalMode OBJECT-TYPE
             SYNTAX  INTEGER {
                         none (1),
                         robbedBit (2),
                         bitOriented (3),
                         messageOriented (4)
                     }
             ACCESS  read-write
             STATUS  mandatory
             DESCRIPTION
                "'none' indicates that no bits are reserved for
                signaling on this channel.

                 'robbedBit' indicates that T1 Robbed Bit  Sig-
                naling is in use.

                 'bitOriented' indicates that E1 Channel  Asso-
                ciated Signaling is in use.

                 'messageOriented' indicates that Common  Chan-
                nel Signaling is in use either on channel 16 of
                an E1 link or channel 24 of a T1."
            ::= { dsx1ConfigEntry 11 }


         dsx1TransmitClockSource OBJECT-TYPE
             SYNTAX  INTEGER {
                         loopTiming (1),
                         localTiming (2),
                         throughTiming (3)
                     }
             ACCESS  read-write
             STATUS  mandatory
             DESCRIPTION
                "The source of Tranmit Clock.




Trunk MIB Working Group                                        [Page 21]

RFC 1406                       DS1/E1 MIB                   January 1993


                 'loopTiming' indicates that the recovered  re-
                ceive clock is used as the transmit clock.

                 'localTiming' indicates  that  a  local  clock
                source is used.

                 'throughTiming' indicates that  recovered  re-
                ceive  clock  from another interface is used as
                the transmit clock."
            ::= { dsx1ConfigEntry 12 }


         dsx1Fdl OBJECT-TYPE
             SYNTAX  INTEGER {
                           other(1),
                           dsx1Ansi-T1-403(2),
                           dsx1Att-54016(4),
                           dsx1Fdl-none(8)
                     }
             ACCESS  read-write
             STATUS  mandatory
             DESCRIPTION
                "This bitmap describes the use of  the  facili-
                ties data link, and is the sum of the capabili-
                ties:

                 'other' indicates that a protocol  other  than
                one following is used.

                 'dsx1Ansi-T1-403' refers to the  FDL  exchange
                recommended by ANSI.

                 'dsx1Att-54016' refers to ESF FDL exchanges.

                 'dsx1Fdl-none' indicates that the device  does
                not use the FDL."
            ::= { dsx1ConfigEntry 13 }


     -- the DS1 Current Table

     -- The DS1 current table contains various statistics being
     -- collected for the current 15 minute interval.

         dsx1CurrentTable OBJECT-TYPE
             SYNTAX  SEQUENCE OF Dsx1CurrentEntry
             ACCESS  not-accessible
             STATUS  mandatory



Trunk MIB Working Group                                        [Page 22]

RFC 1406                       DS1/E1 MIB                   January 1993


             DESCRIPTION
                "The DS1 Current table."
            ::= { ds1 7 }


         dsx1CurrentEntry OBJECT-TYPE
             SYNTAX  Dsx1CurrentEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "An entry in the DS1 Current table."
            INDEX   { dsx1CurrentIndex }
            ::= { dsx1CurrentTable 1 }

     Dsx1CurrentEntry ::=
         SEQUENCE {
             dsx1CurrentIndex
                 INTEGER,
             dsx1CurrentESs
                 Gauge,
             dsx1CurrentSESs
                 Gauge,
             dsx1CurrentSEFSs
                 Gauge,
             dsx1CurrentUASs
                 Gauge,
             dsx1CurrentCSSs
                 Gauge,
             dsx1CurrentPCVs
                 Gauge,
             dsx1CurrentLESs
                 Gauge,
             dsx1CurrentBESs
                 Gauge,
             dsx1CurrentDMs
                 Gauge,
             dsx1CurrentLCVs
                 Gauge
         }

         dsx1CurrentIndex OBJECT-TYPE
             SYNTAX  INTEGER (1..'7fffffff'h)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The index value which uniquely identifies  the
                DS1  interface  to which this entry is applica-
                ble.  The interface identified by a  particular



Trunk MIB Working Group                                        [Page 23]

RFC 1406                       DS1/E1 MIB                   January 1993


                value  of  this  index is the same interface as
                identified by the same value as a dsx1LineIndex
                object instance."
            ::= { dsx1CurrentEntry 1 }


         dsx1CurrentESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Errored Seconds, encountered  by
                a DS1 interface in the current 15 minute inter-
                val."
            ::= { dsx1CurrentEntry 2 }


         dsx1CurrentSESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Severely Errored Seconds encoun-
                tered  by  a  DS1  interface  in the current 15
                minute interval."
            ::= { dsx1CurrentEntry 3 }


         dsx1CurrentSEFSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Severely Errored Framing Seconds
                encountered  by  a DS1 interface in the current
                15 minute interval."
            ::= { dsx1CurrentEntry 4 }


         dsx1CurrentUASs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Unavailable Seconds  encountered
                by a DS1 interface in the current 15 minute in-
                terval."
            ::= { dsx1CurrentEntry 5 }



Trunk MIB Working Group                                        [Page 24]

RFC 1406                       DS1/E1 MIB                   January 1993


         dsx1CurrentCSSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Controlled Slip Seconds  encoun-
                tered  by  a  DS1  interface  in the current 15
                minute interval."
            ::= { dsx1CurrentEntry 6 }


         dsx1CurrentPCVs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Path Coding  Violations  encoun-
                tered  by  a  DS1  interface  in the current 15
                minute interval."
            ::= { dsx1CurrentEntry 7 }


         dsx1CurrentLESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Line Errored Seconds encountered
                by a DS1 interface in the current 15 minute in-
                terval."
            ::= { dsx1CurrentEntry 8 }


         dsx1CurrentBESs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Bursty  Errored  Seconds  (BESs)
                encountered  by  a DS1 interface in the current
                15 minute interval."
            ::= {dsx1CurrentEntry 9 }


         dsx1CurrentDMs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory



Trunk MIB Working Group                                        [Page 25]

RFC 1406                       DS1/E1 MIB                   January 1993


             DESCRIPTION
                "The number of Degraded Minutes  (DMs)  encoun-
                tered  by  a  DS1  interface  in the current 15
                minute interval."
            ::= { dsx1CurrentEntry 10 }


         dsx1CurrentLCVs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Line Code Violations (LCVs)  en-
                countered  by a DS1 interface in the current 15
                minute interval."
         ::= {dsx1CurrentEntry 11 }


     -- the DS1 Interval

     -- The DS1 Interval Table contains various statistics
     -- collected by each DS1 Interface over the previous 24 hours of
     -- operation.  The past 24 hours are broken into 96 completed
     -- 15 minute intervals.

         dsx1IntervalTable OBJECT-TYPE
             SYNTAX  SEQUENCE OF Dsx1IntervalEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "The DS1 Interval table."
            ::= { ds1 8 }


         dsx1IntervalEntry OBJECT-TYPE
             SYNTAX  Dsx1IntervalEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "An entry in the DS1 Interval table."
            INDEX   { dsx1IntervalIndex, dsx1IntervalNumber }
            ::= { dsx1IntervalTable 1 }

     Dsx1IntervalEntry ::=
         SEQUENCE {
             dsx1IntervalIndex
                 INTEGER,
             dsx1IntervalNumber



Trunk MIB Working Group                                        [Page 26]

RFC 1406                       DS1/E1 MIB                   January 1993


                 INTEGER,
             dsx1IntervalESs
                 Gauge,
             dsx1IntervalSESs
                 Gauge,
             dsx1IntervalSEFSs
                 Gauge,
             dsx1IntervalUASs
                 Gauge,
             dsx1IntervalCSSs
                 Gauge,
             dsx1IntervalPCVs
                 Gauge,
             dsx1IntervalLESs
                 Gauge,
             dsx1IntervalBESs
                 Gauge,
             dsx1IntervalDMs
                 Gauge,
             dsx1IntervalLCVs
                 Gauge
         }

         dsx1IntervalIndex OBJECT-TYPE
             SYNTAX  INTEGER (1..'7fffffff'h)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The index value which uniquely identifies  the
                DS1  interface  to which this entry is applica-
                ble.  The interface identified by a  particular
                value  of  this  index is the same interface as
                identified by the same value as a dsx1LineIndex
                object instance."
            ::= { dsx1IntervalEntry 1 }


         dsx1IntervalNumber 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  inter-
                val   (assuming   that  all  96  intervals  are
                valid)."
            ::= { dsx1IntervalEntry 2 }



Trunk MIB Working Group                                        [Page 27]

RFC 1406                       DS1/E1 MIB                   January 1993


         dsx1IntervalESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Errored Seconds encountered by a
                DS1  interface in one of the previous 96, indi-
                vidual 15 minute, intervals."
            ::= { dsx1IntervalEntry 3 }


         dsx1IntervalSESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Severely Errored Seconds encoun-
                tered by a DS1 interface in one of the previous
                96, individual 15 minute, intervals."
            ::= { dsx1IntervalEntry 4 }


         dsx1IntervalSEFSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Severely Errored Framing Seconds
                encountered  by  a  DS1 interface in one of the
                previous 96, individual 15 minute, intervals."
            ::= { dsx1IntervalEntry 5 }


         dsx1IntervalUASs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Unavailable Seconds  encountered
                by  a  DS1 interface in one of the previous 96,
                individual 15 minute, intervals."
            ::= { dsx1IntervalEntry 6 }


         dsx1IntervalCSSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory



Trunk MIB Working Group                                        [Page 28]

RFC 1406                       DS1/E1 MIB                   January 1993


             DESCRIPTION
                "The number of Controlled Slip Seconds  encoun-
                tered by a DS1 interface in one of the previous
                96, individual 15 minute, intervals."
            ::= { dsx1IntervalEntry 7 }


         dsx1IntervalPCVs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Path Coding  Violations  encoun-
                tered by a DS1 interface in one of the previous
                96, individual 15 minute, intervals."
            ::= { dsx1IntervalEntry 8 }


         dsx1IntervalLESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Line Errored Seconds encountered
                by  a  DS1 interface in one of the previous 96,
                individual 15 minute, intervals."
            ::= { dsx1IntervalEntry 9 }


         dsx1IntervalBESs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Bursty  Errored  Seconds  (BESs)
                encountered  by  a  DS1 interface in one of the
                previous 96, individual 15 minute, intervals."
            ::= {dsx1IntervalEntry 10 }


         dsx1IntervalDMs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Degraded Minutes  (DMs)  encoun-
                tered by a DS1 interface in one of the previous
                96, individual 15 minute, intervals."



Trunk MIB Working Group                                        [Page 29]

RFC 1406                       DS1/E1 MIB                   January 1993


            ::= { dsx1IntervalEntry 11 }


         dsx1IntervalLCVs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Line Code Violations (LCVs)  en-
                countered  by a DS1 interface in the current 15
                minute interval."
         ::= {dsx1IntervalEntry 12 }


     -- the DS1 Total

     -- The DS1 Total Table contains the cumulative sum of the
     -- various statistics for the 24 hour period preceding the
     -- current interval.

         dsx1TotalTable OBJECT-TYPE
             SYNTAX  SEQUENCE OF Dsx1TotalEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "The DS1 Total table.  24 hour interval."
            ::= { ds1 9 }


         dsx1TotalEntry OBJECT-TYPE
             SYNTAX  Dsx1TotalEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "An entry in the DS1 Total table."
            INDEX   { dsx1TotalIndex }
            ::= { dsx1TotalTable 1 }

     Dsx1TotalEntry ::=
         SEQUENCE {
             dsx1TotalIndex
                 INTEGER,
             dsx1TotalESs
                 Gauge,
             dsx1TotalSESs
                 Gauge,
             dsx1TotalSEFSs
                 Gauge,



Trunk MIB Working Group                                        [Page 30]

RFC 1406                       DS1/E1 MIB                   January 1993


             dsx1TotalUASs
                 Gauge,
             dsx1TotalCSSs
                 Gauge,
             dsx1TotalPCVs
                 Gauge,
             dsx1TotalLESs
                 Gauge,
             dsx1TotalBESs
                 Gauge,
             dsx1TotalDMs
                 Gauge,
             dsx1TotalLCVs
                 Gauge
         }

         dsx1TotalIndex OBJECT-TYPE
             SYNTAX  INTEGER (1..'7fffffff'h)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The index value which uniquely identifies  the
                DS1  interface  to which this entry is applica-
                ble.  The interface identified by a  particular
                value  of  this  index is the same interface as
                identified by the same value as a dsx1LineIndex
                object instance."
            ::= { dsx1TotalEntry 1 }


         dsx1TotalESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Errored Seconds encountered by a
                DS1 interface in the previous 24 hour interval"
            ::= { dsx1TotalEntry 2 }


         dsx1TotalSESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Severely Errored Seconds encoun-
                tered  by  a  DS1  interface in the previous 24
                hour interval."



Trunk MIB Working Group                                        [Page 31]

RFC 1406                       DS1/E1 MIB                   January 1993


            ::= { dsx1TotalEntry 3 }


         dsx1TotalSEFSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Severely Errored Framing Seconds
                encountered  by a DS1 interface in the previous
                24 hour interval."
            ::= { dsx1TotalEntry 4 }


         dsx1TotalUASs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Unavailable Seconds  encountered
                by  a DS1 interface in the previous 24 hour in-
                terval."
            ::= { dsx1TotalEntry 5 }


         dsx1TotalCSSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Controlled Slip Seconds  encoun-
                tered  by  a  DS1  interface in the previous 24
                hour interval."
            ::= { dsx1TotalEntry 6 }


         dsx1TotalPCVs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Path Coding  Violations  encoun-
                tered  by  a  DS1  interface in the previous 24
                hour interval."
            ::= { dsx1TotalEntry 7 }






Trunk MIB Working Group                                        [Page 32]

RFC 1406                       DS1/E1 MIB                   January 1993


         dsx1TotalLESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Line Errored Seconds encountered
                by  a DS1 interface in the previous 24 hour in-
                terval."
            ::= { dsx1TotalEntry 8 }


         dsx1TotalBESs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Bursty  Errored  Seconds  (BESs)
                encountered  by a DS1 interface in the previous
                24 hour interval."
            ::= { dsx1TotalEntry 9 }


         dsx1TotalDMs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Degraded Minutes  (DMs)  encoun-
                tered  by  a  DS1  interface in the previous 24
                hour interval."
            ::= { dsx1TotalEntry 10 }


         dsx1TotalLCVs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Line Code Violations (LCVs)  en-
                countered  by a DS1 interface in the current 15
                minute interval."
         ::= {dsx1TotalEntry 11 }


     -- The DS1 Far End Group

     -- Implementation of this group is optional for all systems
     -- that attach to a DS1 Interface.



Trunk MIB Working Group                                        [Page 33]

RFC 1406                       DS1/E1 MIB                   January 1993


     -- The DS1 Far End Group consists of three tables:
     --   DS1 Far End Current
     --   DS1 Far End Interval
     --   DS1 Far End Total

     -- The DS1 Far End Current Table

     -- The DS1 Far End Current table contains various statistics
     -- being collected for the current 15 minute interval.
     -- The statistics are collected from the far end messages on the
     -- Facilities Data Link.  The definitions are the same as
     -- described for the near-end information.

         dsx1FarEndCurrentTable OBJECT-TYPE
             SYNTAX  SEQUENCE OF Dsx1FarEndCurrentEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "The DS1 Far End Current table."
            ::= { ds1 10 }


         dsx1FarEndCurrentEntry OBJECT-TYPE
             SYNTAX  Dsx1FarEndCurrentEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "An entry in the DS1 Far End Current table."
            INDEX   { dsx1FarEndCurrentIndex }
            ::= { dsx1FarEndCurrentTable 1 }

      Dsx1FarEndCurrentEntry ::=
         SEQUENCE {
             dsx1FarEndCurrentIndex
                 INTEGER,
             dsx1FarEndTimeElapsed
                 INTEGER,
             dsx1FarEndValidIntervals
                 INTEGER,
             dsx1FarEndCurrentESs
                 Gauge,
             dsx1FarEndCurrentSESs
                 Gauge,
             dsx1FarEndCurrentSEFSs
                 Gauge,
             dsx1FarEndCurrentUASs
                 Gauge,
             dsx1FarEndCurrentCSSs



Trunk MIB Working Group                                        [Page 34]

RFC 1406                       DS1/E1 MIB                   January 1993


                 Gauge,
             dsx1FarEndCurrentLESs
                 Gauge,
             dsx1FarEndCurrentPCVs
                 Gauge,
             dsx1FarEndCurrentBESs
                 Gauge,
             dsx1FarEndCurrentDMs
                 Gauge
         }

         dsx1FarEndCurrentIndex OBJECT-TYPE
             SYNTAX  INTEGER (1..'7fffffff'h)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The index value which uniquely identifies  the
                DS1  interface  to which this entry is applica-
                ble.  The interface identified by a  particular
                value  of  this  index is the same interface as
                identified by the same value  an  dsx1LineIndex
                object instance."
            ::= { dsx1FarEndCurrentEntry 1 }


         dsx1FarEndTimeElapsed OBJECT-TYPE
             SYNTAX  INTEGER (0..899)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                     "The number of seconds that  have  elapsed
                     since the beginning of the far end current
                     error-measurement period."
            ::= { dsx1FarEndCurrentEntry 2 }


         dsx1FarEndValidIntervals OBJECT-TYPE
             SYNTAX  INTEGER (0..96)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                     "The number of previous far end  intervals
                     for  which  valid data was collected.  The
                     value will be 96 unless the interface  was
                     brought  online  within the last 24 hours,
                     in which case the value will be the number
                     of  complete  15  minute far end intervals
                     since the interface has been online."



Trunk MIB Working Group                                        [Page 35]

RFC 1406                       DS1/E1 MIB                   January 1993


            ::= { dsx1FarEndCurrentEntry 3 }


         dsx1FarEndCurrentESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far Far End Errored Seconds  en-
                countered  by a DS1 interface in the current 15
                minute interval."
            ::= { dsx1FarEndCurrentEntry 4 }


         dsx1FarEndCurrentSESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Severely Errored Seconds
                encountered  by  a DS1 interface in the current
                15 minute interval."
            ::= { dsx1FarEndCurrentEntry 5 }


         dsx1FarEndCurrentSEFSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Severely Errored Framing
                Seconds  encountered  by a DS1 interface in the
                current 15 minute interval."
            ::= { dsx1FarEndCurrentEntry 6 }


         dsx1FarEndCurrentUASs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Unavailable Seconds  encountered
                by a DS1 interface in the current 15 minute in-
                terval."
            ::= { dsx1FarEndCurrentEntry 7 }






Trunk MIB Working Group                                        [Page 36]

RFC 1406                       DS1/E1 MIB                   January 1993


         dsx1FarEndCurrentCSSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Controlled Slip  Seconds
                encountered  by  a DS1 interface in the current
                15 minute interval."
            ::= { dsx1FarEndCurrentEntry 8 }


         dsx1FarEndCurrentLESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Line Errored Seconds en-
                countered  by a DS1 interface in the current 15
                minute interval."
            ::= { dsx1FarEndCurrentEntry 9 }


         dsx1FarEndCurrentPCVs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Path  Coding  Violations
                reported  via the far end block error count en-
                countered by a DS1 interface in the current  15
                minute interval."
            ::= { dsx1FarEndCurrentEntry 10 }


         dsx1FarEndCurrentBESs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Bursty  Errored  Seconds  (BESs)
                encountered  by  a DS1 interface in the current
                15 minute interval."
            ::= {dsx1FarEndCurrentEntry 11 }


         dsx1FarEndCurrentDMs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only



Trunk MIB Working Group                                        [Page 37]

RFC 1406                       DS1/E1 MIB                   January 1993


             STATUS mandatory
             DESCRIPTION
                "The number of Degraded Minutes  (DMs)  encoun-
                tered  by  a  DS1  interface  in the current 15
                minute interval."
            ::= { dsx1FarEndCurrentEntry 12 }


     -- The DS1 Far End Interval Table

     -- The DS1 Far End Interval Table contains various statistics
     -- collected by each DS1 interface over the previous 24 hours of
     -- operation.  The past 24 hours are broken into 96
     -- completed 15 minute intervals.

         dsx1FarEndIntervalTable OBJECT-TYPE
             SYNTAX  SEQUENCE OF Dsx1FarEndIntervalEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "The DS1 Far End Interval table."
            ::= { ds1 11 }


         dsx1FarEndIntervalEntry OBJECT-TYPE
             SYNTAX  Dsx1FarEndIntervalEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "An entry in the DS1 Far End Interval table."
            INDEX   { dsx1FarEndIntervalIndex,
                      dsx1FarEndIntervalNumber }
            ::= { dsx1FarEndIntervalTable 1 }

     Dsx1FarEndIntervalEntry ::=
         SEQUENCE {
             dsx1FarEndIntervalIndex
                 INTEGER,
             dsx1FarEndIntervalNumber
                 INTEGER,
             dsx1FarEndIntervalESs
                 Gauge,
             dsx1FarEndIntervalSESs
                 Gauge,
             dsx1FarEndIntervalSEFSs
                 Gauge,
             dsx1FarEndIntervalUASs
                 Gauge,



Trunk MIB Working Group                                        [Page 38]

RFC 1406                       DS1/E1 MIB                   January 1993


             dsx1FarEndIntervalCSSs
                 Gauge,
             dsx1FarEndIntervalLESs
                 Gauge,
             dsx1FarEndIntervalPCVs
                 Gauge,
             dsx1FarEndIntervalBESs
                 Gauge,
             dsx1FarEndIntervalDMs
                 Gauge
         }

         dsx1FarEndIntervalIndex OBJECT-TYPE
             SYNTAX  INTEGER (1..'7fffffff'h)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The index value which uniquely identifies  the
                DS1  interface  to which this entry is applica-
                ble.  The interface identified by a  particular
                value  of  this  index is the same interface as
                identified by the same value as a dsx1LineIndex
                object instance."
            ::= { dsx1FarEndIntervalEntry 1 }


         dsx1FarEndIntervalNumber 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  inter-
                val   (assuming   that  all  96  intervals  are
                valid)."
            ::= { dsx1FarEndIntervalEntry 2 }


         dsx1FarEndIntervalESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Errored Seconds  encoun-
                tered by a DS1 interface in one of the previous
                96, individual 15 minute, intervals."
            ::= { dsx1FarEndIntervalEntry 3 }



Trunk MIB Working Group                                        [Page 39]

RFC 1406                       DS1/E1 MIB                   January 1993


         dsx1FarEndIntervalSESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Severely Errored Seconds
                encountered  by  a  DS1 interface in one of the
                previous 96, individual 15 minute, intervals."
            ::= { dsx1FarEndIntervalEntry 4 }


         dsx1FarEndIntervalSEFSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Severely Errored Framing
                Seconds  encountered  by a DS1 interface in one
                of the previous 96, individual 15  minute,  in-
                tervals."
            ::= { dsx1FarEndIntervalEntry 5 }


         dsx1FarEndIntervalUASs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Unavailable Seconds  encountered
                by  a  DS1 interface in one of the previous 96,
                individual 15 minute, intervals."
            ::= { dsx1FarEndIntervalEntry 6 }


         dsx1FarEndIntervalCSSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Controlled Slip  Seconds
                encountered  by  a  DS1 interface in one of the
                previous 96, individual 15 minute, intervals."
            ::= { dsx1FarEndIntervalEntry 7 }


         dsx1FarEndIntervalLESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only



Trunk MIB Working Group                                        [Page 40]

RFC 1406                       DS1/E1 MIB                   January 1993


             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Line Errored Seconds en-
                countered by a DS1 interface in one of the pre-
                vious 96, individual 15 minute, intervals."
            ::= { dsx1FarEndIntervalEntry 8 }


         dsx1FarEndIntervalPCVs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Path  Coding  Violations
                reported  via the far end block error count en-
                countered by a DS1 interface in one of the pre-
                vious 96, individual 15 minute, intervals."
            ::= { dsx1FarEndIntervalEntry 9 }


         dsx1FarEndIntervalBESs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Bursty  Errored  Seconds  (BESs)
                encountered  by  a  DS1 interface in one of the
                previous 96, individual 15 minute, intervals."
            ::= {dsx1FarEndIntervalEntry 10 }


         dsx1FarEndIntervalDMs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Degraded Minutes  (DMs)  encoun-
                tered by a DS1 interface in one of the previous
                96, individual 15 minute, intervals."
            ::= { dsx1FarEndIntervalEntry 11 }


     -- The DS1 Far End Total Table

     -- The DS1 Far End Total Table contains the cumulative sum of the
     -- various statistics for the 24 hour period preceding the
     -- current interval.




Trunk MIB Working Group                                        [Page 41]

RFC 1406                       DS1/E1 MIB                   January 1993


         dsx1FarEndTotalTable OBJECT-TYPE
             SYNTAX  SEQUENCE OF Dsx1FarEndTotalEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "The DS1 Far End Total table."
            ::= { ds1 12 }


         dsx1FarEndTotalEntry OBJECT-TYPE
             SYNTAX  Dsx1FarEndTotalEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "An entry in the DS1 Far End Total table."
            INDEX   { dsx1FarEndTotalIndex }
            ::= { dsx1FarEndTotalTable 1 }

     Dsx1FarEndTotalEntry ::=
         SEQUENCE {
             dsx1FarEndTotalIndex
                 INTEGER,
             dsx1FarEndTotalESs
                 Gauge,
             dsx1FarEndTotalSESs
                 Gauge,
             dsx1FarEndTotalSEFSs
                 Gauge,
             dsx1FarEndTotalUASs
                 Gauge,
             dsx1FarEndTotalCSSs
                 Gauge,
             dsx1FarEndTotalLESs
                 Gauge,
             dsx1FarEndTotalPCVs
                 Gauge,
             dsx1FarEndTotalBESs
                 Gauge,
             dsx1FarEndTotalDMs
                 Gauge
         }

         dsx1FarEndTotalIndex OBJECT-TYPE
             SYNTAX  INTEGER (1..'7fffffff'h)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The index value which uniquely identifies  the



Trunk MIB Working Group                                        [Page 42]

RFC 1406                       DS1/E1 MIB                   January 1993


                DS1  interface  to which this entry is applica-
                ble.  The interface identified by a  particular
                value  of  this  index is the same interface as
                identified by the same value  an  dsx1LineIndex
                object instance."
            ::= { dsx1FarEndTotalEntry 1 }


         dsx1FarEndTotalESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Errored Seconds  encoun-
                tered  by  a  DS1  interface in the previous 24
                hour interval."
            ::= { dsx1FarEndTotalEntry 2 }


         dsx1FarEndTotalSESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Severely Errored Seconds
                encountered  by a DS1 interface in the previous
                24 hour interval."
            ::= { dsx1FarEndTotalEntry 3 }


         dsx1FarEndTotalSEFSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Severely Errored Framing
                Seconds  encountered  by a DS1 interface in the
                previous 24 hour interval."
            ::= { dsx1FarEndTotalEntry 4 }


         dsx1FarEndTotalUASs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Unavailable Seconds  encountered
                by  a DS1 interface in the previous 24 hour in-



Trunk MIB Working Group                                        [Page 43]

RFC 1406                       DS1/E1 MIB                   January 1993


                terval."
            ::= { dsx1FarEndTotalEntry 5 }


         dsx1FarEndTotalCSSs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Controlled Slip  Seconds
                encountered  by a DS1 interface in the previous
                24 hour interval."
            ::= { dsx1FarEndTotalEntry 6 }


         dsx1FarEndTotalLESs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Line Errored Seconds en-
                countered by a DS1 interface in the previous 24
                hour interval."
            ::= { dsx1FarEndTotalEntry 7 }


         dsx1FarEndTotalPCVs OBJECT-TYPE
             SYNTAX  Gauge
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The number of Far End Path  Coding  Violations
                reported  via the far end block error count en-
                countered by a DS1 interface in the previous 24
                hour interval."
            ::= { dsx1FarEndTotalEntry 8 }


         dsx1FarEndTotalBESs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Bursty  Errored  Seconds  (BESs)
                encountered  by a DS1 interface in the previous
                24 hour interval."
            ::= { dsx1FarEndTotalEntry 9 }




Trunk MIB Working Group                                        [Page 44]

RFC 1406                       DS1/E1 MIB                   January 1993


         dsx1FarEndTotalDMs OBJECT-TYPE
             SYNTAX Gauge
             ACCESS read-only
             STATUS mandatory
             DESCRIPTION
                "The number of Degraded Minutes  (DMs)  encoun-
                tered  by  a  DS1  interface in the previous 24
                hour interval."
            ::= { dsx1FarEndTotalEntry 10 }


     -- the DS1 Fractional Group

     -- Implementation of this group is mandatory for those
     -- systems dividing a DS1 into channels containing different
     -- data streams that are of local interest.  Systems which
     -- are indifferent to data content, such as CSUs, need not
     -- implement it.

     -- The DS1 fractional table identifies which DS1 channels
     -- associated with a CSU are being used to support a
     -- logical interface, i.e., an entry in the interfaces table
     -- from the Internet-standard MIB.

     -- For example, consider an application managing a North
     -- American ISDN Primary Rate link whose division is a 384 kbit/s
     -- H1 "B" Channel for Video, a second H1 for data to a primary
     -- routing peer, and 12 64 kbit/s H0 "B" Channels. Consider that
     -- some subset of the H0 channels are used for voice and the
     -- remainder are available for dynamic data calls.

     -- we count a total of 14 interfaces multiplexed onto the DS1
     -- interface. Six DS1 channels (for the sake of the example,
     -- channels 1..6) are used for Video, six more (7..11 and 13)
     -- are used for data, and the remaining 12 are are in channels
     -- 12 and 14..24.

     -- Let us further imagine that ifIndex 2 is of type DS1 and
     -- refers to the DS1 interface, and that the interfaces layered
     -- onto it are numbered 3..16.

     -- We might describe the allocation of channels, in the
     -- dsx1FracTable, as follows:

     -- dsx1FracIfIndex.2. 1 = 3    dsx1FracIfIndex.2.13 = 4
     -- dsx1FracIfIndex.2. 2 = 3    dsx1FracIfIndex.2.14 = 6
     -- dsx1FracIfIndex.2. 3 = 3    dsx1FracIfIndex.2.15 = 7
     -- dsx1FracIfIndex.2. 4 = 3    dsx1FracIfIndex.2.16 = 8



Trunk MIB Working Group                                        [Page 45]

RFC 1406                       DS1/E1 MIB                   January 1993


     -- dsx1FracIfIndex.2. 5 = 3    dsx1FracIfIndex.2.17 = 9
     -- dsx1FracIfIndex.2. 6 = 3    dsx1FracIfIndex.2.18 = 10
     -- dsx1FracIfIndex.2. 7 = 4    dsx1FracIfIndex.2.19 = 11
     -- dsx1FracIfIndex.2. 8 = 4    dsx1FracIfIndex.2.20 = 12
     -- dsx1FracIfIndex.2. 9 = 4    dsx1FracIfIndex.2.21 = 13
     -- dsx1FracIfIndex.2.10 = 4    dsx1FracIfIndex.2.22 = 14
     -- dsx1FracIfIndex.2.11 = 4    dsx1FracIfIndex.2.23 = 15
     -- dsx1FracIfIndex.2.12 = 5    dsx1FracIfIndex.2.24 = 16


     --      For North American (DS1) interfaces, there are 24 legal
     --      channels, numbered 1 through 24.

     --      For G.704 interfaces, there are 31 legal channels,
     --      numbered 1 through 31.  The channels (1..31) correspond
     --      directly to the equivalently numbered time-slots.

         dsx1FracTable OBJECT-TYPE
             SYNTAX  SEQUENCE OF Dsx1FracEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "The DS1 Fractional table."
            ::= { ds1 13 }


         dsx1FracEntry OBJECT-TYPE
             SYNTAX  Dsx1FracEntry
             ACCESS  not-accessible
             STATUS  mandatory
             DESCRIPTION
                "An entry in the DS1 Fractional table."
            INDEX   { dsx1FracIndex, dsx1FracNumber }
            ::= { dsx1FracTable 1 }

     Dsx1FracEntry ::=
         SEQUENCE {
             dsx1FracIndex
                 INTEGER,
             dsx1FracNumber
                 INTEGER,
             dsx1FracIfIndex
                 INTEGER
         }


         dsx1FracIndex OBJECT-TYPE
             SYNTAX  INTEGER (1..'7fffffff'h)



Trunk MIB Working Group                                        [Page 46]

RFC 1406                       DS1/E1 MIB                   January 1993


             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The index value which uniquely identifies  the
                DS1  interface  to which this entry is applica-
                ble.  The interface identified by a  particular
                value  of  this  index is the same interface as
                identified by the same value  an  dsx1LineIndex
                object instance."
            ::= { dsx1FracEntry 1 }


         dsx1FracNumber OBJECT-TYPE
             SYNTAX  INTEGER (1..31)
             ACCESS  read-only
             STATUS  mandatory
             DESCRIPTION
                "The channel number for this entry."
            ::= { dsx1FracEntry 2 }


         dsx1FracIfIndex OBJECT-TYPE
             SYNTAX  INTEGER (1..'7fffffff'h)
             ACCESS  read-write
             STATUS  mandatory
             DESCRIPTION
                "An index value that uniquely identifies an in-
                terface.  The interface identified by a partic-
                ular value of this index is the same  interface
                as  identified by the same value an ifIndex ob-
                ject instance. If no interface is currently us-
                ing  a channel, the value should be zero.  If a
                single interface occupies more  than  one  time
                slot,  that ifIndex value will be found in mul-
                tiple time slots."
            ::= { dsx1FracEntry 3 }

     END

5.  Acknowledgements

   This document was produced by the Trunk MIB Working Group:

          Tracy Cox       Bellcore
          Fred Baker      Advanced Computer Communications
          James Watt      Newbridge
          Bill Versteeg   Versteeg Codeworks
          Steve Buchko    Newbridge



Trunk MIB Working Group                                        [Page 47]

RFC 1406                       DS1/E1 MIB                   January 1993


          Greg Celmainis  Newbridge
          Kaj Tesink      Bellcore
          Al Bryenton     Bell Northern Research
          Tom Easterday   CIC
          John Labbe      Merit Corporation
          Chris Sullivan  Gandalf Ltd
          Grant Hall      Gandalf Ltd
          Laurence V. Marks, IBM Corp.
          Kurt Hall, Clear Communications Corp.
          Myron Hattig, ADC Kentrox

   Tracy Cox, Bill Versteeg, Myron Hattig, Kurt Hall and Laurence Marks
   especially worked to make the document what it is.

6.  References

   [1] Rose M., and K. McCloghrie, "Structure and Identification of
       Management Information for TCP/IP-based internets", STD 16, RFC
       1155, Performance Systems International, Hughes LAN Systems, May
       1990.

   [2] Rose, M., and K. McCloghrie, Editors, "Concise MIB Definitions",
       STD 16, RFC 1212, Performance Systems International, Hughes LAN
       Systems, March 1991.

   [3] 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.

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

   [5] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple
       Network Management Protocol", STD 15, RFC 1157, SNMP Research,
       Performance Systems International, Performance Systems
       International, MIT Laboratory for Computer Science, May 1990.

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

   [7] 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.




Trunk MIB Working Group                                        [Page 48]

RFC 1406                       DS1/E1 MIB                   January 1993


   [8] AT&T Information Systems, AT&T ESF DS1 Channel Service Unit
       User's Manual, 999-100-305, February 1988.

   [9] AT&T Technical Reference, Requirements for Interfacing Digital
       Terminal Equipment to Services Employing the Extended Superframe
       Format, Publication 54016, May 1988.

  [10] American National Standard for Telecommunications -- Carrier-to-
       Customer Installation - DS1 Metallic Interface, T1.403, February
       1989.

  [11] CCITT Specifications Volume III, Recommendation G.703,
       Physical/Electrical Characteristics of Hierarchical Digital
       Interfaces, July 1988.

  [12] CCITT Specifications Volume III, Recommendation G.704,
       Synchronous frame structures used at primary and secondary
       hierarchical levels, July 1988.

  [13] American National Standard for Telecommunications -- Layer 1 In-
       Service Digital Transmission Performance Monitoring T1M1/92-0xx,
       T1M1.3/92-005R1, April 1992.

  [14] CCITT Specifications Volume IV, Recommendation O.162, Equipment
       To Perform In Service Monitoring On 2048 kbit/s Signals, July
       1988

  [15] CCITT Specifications Volume III, Recommendation G.821, Error
       Performance Of An International Digital Connection Forming Part
       Of An Integrated Services Digital Network, July 1988.

  [16] AT&T Technical Reference, Technical Reference 62411, ACCUNET T1.5
       Service Description And Interface Specification, December 1990.

  [17] CCITT Specifications Volume III, Recommendation G.706, Frame
       Alignment and Cyclic Redundancy Check (CRC) Procedures Relating
       to Basic Frame Structures Defined in Recommendation G.704, July
       1988.

  [18] CCITT Specifications Volume III, Recommendation G.732,
       Characteristics Of Primary PCM Multiplex Equipment Operating at
       2048 kbit/s, July 1988.









Trunk MIB Working Group                                        [Page 49]

RFC 1406                       DS1/E1 MIB                   January 1993


Security Considerations

   Security issues are not discussed in this memo.

Authors' Addresses

   Fred Baker
   Advanced Computer Communications
   315 Bollay Drive
   Santa Barbara, California 93117

   Phone: (805) 685-4455
   EMail: fbaker@acc.com


   James Watt
   Newbridge Networks Corporation
   600 March Road
   Kanata, Ontario
   Canada K2K 2E6

   Phone: (613) 591-3600
   EMail: james@newbridge.com




























Trunk MIB Working Group                                        [Page 50]


Html markup produced by rfcmarkup 1.107, available from http://tools.ietf.org/tools/rfcmarkup/