tech-invite   World Map
3GPP     Specs     Glossaries     UICC       IETF     RFCs     Groups     SIP     ABNFs       T+       Search     Home

RFC 4805

 
 
 

Definitions of Managed Objects for the DS1, J1, E1, DS2, and E2 Interface Types

Part 4 of 4, p. 77 to 94
Prev RFC Part

 


prevText      Top      Up      ToC       Page 77 
   ds1NearEndStatisticsGroup OBJECT-GROUP
       OBJECTS { dsx1CurrentIndex,
                 dsx1CurrentESs,
                 dsx1CurrentSESs,
                 dsx1CurrentSEFSs,
                 dsx1CurrentUASs,
                 dsx1CurrentCSSs,
                 dsx1CurrentPCVs,
                 dsx1CurrentLESs,
                 dsx1CurrentBESs,
                 dsx1CurrentDMs,
                 dsx1CurrentLCVs,
                 dsx1IntervalIndex,
                 dsx1IntervalNumber,
                 dsx1IntervalESs,
                 dsx1IntervalSESs,
                 dsx1IntervalSEFSs,
                 dsx1IntervalUASs,
                 dsx1IntervalCSSs,
                 dsx1IntervalPCVs,
                 dsx1IntervalLESs,
                 dsx1IntervalBESs,
                 dsx1IntervalDMs,
                 dsx1IntervalLCVs,
                 dsx1IntervalValidData,
                 dsx1TotalIndex,
                 dsx1TotalESs,
                 dsx1TotalSESs,
                 dsx1TotalSEFSs,
                 dsx1TotalUASs,
                 dsx1TotalCSSs,
                 dsx1TotalPCVs,
                 dsx1TotalLESs,
                 dsx1TotalBESs,
                 dsx1TotalDMs,
                 dsx1TotalLCVs }
       STATUS  deprecated
       DESCRIPTION
               "A collection of objects providing statistics
               information applicable to all DS1 interfaces."
       ::= { ds1Groups 2 }

   ds1FarEndGroup  OBJECT-GROUP
       OBJECTS { dsx1FarEndCurrentIndex,
                 dsx1FarEndTimeElapsed,
                 dsx1FarEndValidIntervals,
                 dsx1FarEndCurrentESs,
                 dsx1FarEndCurrentSESs,

Top      Up      ToC       Page 78 
                 dsx1FarEndCurrentSEFSs,
                 dsx1FarEndCurrentUASs,
                 dsx1FarEndCurrentCSSs,
                 dsx1FarEndCurrentLESs,
                 dsx1FarEndCurrentPCVs,
                 dsx1FarEndCurrentBESs,
                 dsx1FarEndCurrentDMs,
                 dsx1FarEndInvalidIntervals,
                 dsx1FarEndIntervalIndex,
                 dsx1FarEndIntervalNumber,
                 dsx1FarEndIntervalESs,
                 dsx1FarEndIntervalSESs,
                 dsx1FarEndIntervalSEFSs,
                 dsx1FarEndIntervalUASs,
                 dsx1FarEndIntervalCSSs,
                 dsx1FarEndIntervalLESs,
                 dsx1FarEndIntervalPCVs,
                 dsx1FarEndIntervalBESs,
                 dsx1FarEndIntervalDMs,
                 dsx1FarEndIntervalValidData,
                 dsx1FarEndTotalIndex,
                 dsx1FarEndTotalESs,
                 dsx1FarEndTotalSESs,
                 dsx1FarEndTotalSEFSs,
                 dsx1FarEndTotalUASs,
                 dsx1FarEndTotalCSSs,
                 dsx1FarEndTotalLESs,
                 dsx1FarEndTotalPCVs,
                 dsx1FarEndTotalBESs,
                 dsx1FarEndTotalDMs }
       STATUS  deprecated
       DESCRIPTION
               "A collection of objects providing remote
               configuration and statistics information."
       ::= { ds1Groups 3 }

   ds1DeprecatedGroup OBJECT-GROUP
       OBJECTS { dsx1IfIndex,
                 dsx1FracIndex,
                 dsx1FracNumber,
                 dsx1FracIfIndex }
       STATUS  deprecated
       DESCRIPTION
               "A collection of obsolete objects that may be
               implemented for backwards compatibility."
       ::= { ds1Groups 4 }

   ds1NearEndOptionalConfigGroup OBJECT-GROUP

Top      Up      ToC       Page 79 
       OBJECTS { dsx1LineStatusLastChange,
                 dsx1LineStatusChangeTrapEnable }

       STATUS    current
       DESCRIPTION
               "A collection of objects that may be implemented
               on DS1 and DS2 interfaces."
       ::= { ds1Groups 5 }

   ds1DS2Group OBJECT-GROUP
       OBJECTS { dsx1LineIndex,
                 dsx1LineType,
                 dsx1LineCoding,
                 dsx1SendCode,
                 dsx1LineStatus,
                 dsx1SignalMode,
                 dsx1TransmitClockSource,
                 dsx1Channelization }
       STATUS   current
       DESCRIPTION
               "A collection of objects providing information
               about DS2 (6,312 kbps) and E2 (8,448 kbps)
               systems."
       ::= { ds1Groups 6 }

   ds1TransStatsGroup OBJECT-GROUP
       OBJECTS { dsx1CurrentESs,
                 dsx1CurrentSESs,
                 dsx1CurrentUASs,
                 dsx1IntervalESs,
                 dsx1IntervalSESs,
                 dsx1IntervalUASs,
                 dsx1TotalESs,
                 dsx1TotalSESs,
                 dsx1TotalUASs }
       STATUS   current
       DESCRIPTION
               "A collection of objects that are the
               statistics that can be collected from a DS1
               interface that is running transparent or unframed
               lineType.  Statistics not in this list should
               return noSuchInstance."
       ::= { ds1Groups 7 }

   ds1NearEndOptionalTrapGroup NOTIFICATION-GROUP
       NOTIFICATIONS { dsx1LineStatusChange }
       STATUS    current
       DESCRIPTION

Top      Up      ToC       Page 80 
               "A collection of notifications that may be
               implemented on DS1 and DS2 interfaces."
       ::= { ds1Groups 8 }

   ds1ChanMappingGroup OBJECT-GROUP
       OBJECTS { dsx1ChanMappedIfIndex }
       STATUS    current
       DESCRIPTION
               "A collection of objects that give a mapping of
               DS3 Channel (dsx1Ds1ChannelNumber) to ifIndex."
       ::= { ds1Groups 9 }

   ds1NearEndConfigurationGroup  OBJECT-GROUP
       OBJECTS { dsx1LineIndex,
                 dsx1TimeElapsed,
                 dsx1ValidIntervals,
                 dsx1LineType,
                 dsx1LineCoding,
                 dsx1SendCode,
                 dsx1CircuitIdentifier,
                 dsx1LoopbackConfig,
                 dsx1LineStatus,
                 dsx1SignalMode,
                 dsx1TransmitClockSource,
                 dsx1Fdl,
                 dsx1InvalidIntervals,
                 dsx1LineLength,
                 dsx1LoopbackStatus,
                 dsx1Ds1ChannelNumber,
                 dsx1Channelization,
                 dsx1LineMode,
                 dsx1LineBuildOut                      }
       STATUS  deprecated
       DESCRIPTION
               "A collection of objects providing configuration
               information applicable to all DS1 interfaces."
       ::= { ds1Groups 10 }

   ds1NearEndCfgGroup  OBJECT-GROUP
       OBJECTS { dsx1LineIndex,
                 dsx1TimeElapsed,
                 dsx1ValidIntervals,
                 dsx1LineType,
                 dsx1LineCoding,
                 dsx1SendCode,
                 dsx1CircuitIdentifier,
                 dsx1LoopbackConfig,
                 dsx1LineStatus,

Top      Up      ToC       Page 81 
                 dsx1SignalMode,
                 dsx1TransmitClockSource,
                 dsx1Fdl,
                 dsx1InvalidIntervals,
                 dsx1LineLength,
                 dsx1LoopbackStatus,
                 dsx1Ds1ChannelNumber,
                 dsx1Channelization,
                 dsx1LineMode,
                 dsx1LineBuildOut,
                 dsx1LineImpedance                     }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing configuration
               information applicable to all DS1 interfaces."
       ::= { ds1Groups 11 }

   ds1NearEndStatGroup OBJECT-GROUP
       OBJECTS { dsx1CurrentIndex,
                 dsx1CurrentESs,
                 dsx1CurrentSESs,
                 dsx1CurrentSEFSs,
                 dsx1CurrentUASs,
                 dsx1CurrentCSSs,
                 dsx1CurrentPCVs,
                 dsx1CurrentLESs,
                 dsx1CurrentBESs,
                 dsx1CurrentLCVs,
                 dsx1IntervalIndex,
                 dsx1IntervalNumber,
                 dsx1IntervalESs,
                 dsx1IntervalSESs,
                 dsx1IntervalSEFSs,
                 dsx1IntervalUASs,
                 dsx1IntervalCSSs,
                 dsx1IntervalPCVs,
                 dsx1IntervalLESs,
                 dsx1IntervalBESs,
                 dsx1IntervalLCVs,
                 dsx1IntervalValidData,
                 dsx1TotalIndex,
                 dsx1TotalESs,
                 dsx1TotalSESs,
                 dsx1TotalSEFSs,
                 dsx1TotalUASs,
                 dsx1TotalCSSs,
                 dsx1TotalPCVs,
                 dsx1TotalLESs,

Top      Up      ToC       Page 82 
                 dsx1TotalBESs,
                 dsx1TotalLCVs }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing statistics
               information applicable to all DS1 interfaces."
       ::= { ds1Groups 12 }

   ds1FarEndNGroup  OBJECT-GROUP
       OBJECTS { dsx1FarEndCurrentIndex,
                 dsx1FarEndTimeElapsed,
                 dsx1FarEndValidIntervals,
                 dsx1FarEndCurrentESs,
                 dsx1FarEndCurrentSESs,
                 dsx1FarEndCurrentSEFSs,
                 dsx1FarEndCurrentUASs,
                 dsx1FarEndCurrentCSSs,
                 dsx1FarEndCurrentLESs,
                 dsx1FarEndCurrentPCVs,
                 dsx1FarEndCurrentBESs,
                 dsx1FarEndInvalidIntervals,
                 dsx1FarEndIntervalIndex,
                 dsx1FarEndIntervalNumber,
                 dsx1FarEndIntervalESs,
                 dsx1FarEndIntervalSESs,
                 dsx1FarEndIntervalSEFSs,
                 dsx1FarEndIntervalUASs,
                 dsx1FarEndIntervalCSSs,
                 dsx1FarEndIntervalLESs,
                 dsx1FarEndIntervalPCVs,
                 dsx1FarEndIntervalBESs,
                 dsx1FarEndIntervalValidData,
                 dsx1FarEndTotalIndex,
                 dsx1FarEndTotalESs,
                 dsx1FarEndTotalSESs,
                 dsx1FarEndTotalSEFSs,
                 dsx1FarEndTotalUASs,
                 dsx1FarEndTotalCSSs,
                 dsx1FarEndTotalLESs,
                 dsx1FarEndTotalPCVs,
                 dsx1FarEndTotalBESs}
       STATUS  current
       DESCRIPTION
               "A collection of objects providing remote
               configuration and statistics information."
       ::= { ds1Groups 13 }
   END

Top      Up      ToC       Page 83 
5.  Security Considerations

   There are a number of management objects defined in this MIB module
   with a MAX-ACCESS clause of read-write.  Such objects may be
   considered sensitive or vulnerable in some network environments.  The
   support for SET operations in a non-secure environment without proper
   protection can have a negative effect on network operations.  The
   specific objects and their sensitivities/vulnerabilities are as
   follows.

   Setting the following objects to incorrect values may result in
   traffic interruptions:

      dsx1LineType
      dsx1LineCoding
      dsx1SendCode
      dsx1LoopbackConfig
      dsx1SignalMode
      dsx1TransmitClockSource
      dsx1Fdl
      dsx1LineLength
      dsx1Channelization
      dsx1LineMode
      dsx1LineBuildOut
      dsx1LineImpedance

   In the case of dsx1LineType, for example, both ends of a DS1/E1 must
   have the same value in order for traffic to flow.  In the case of
   dsx1SendCode and dsx1LoopbackConfig, for another example, traffic may
   stop transmitting when particular loopbacks are applied.

   Setting the following object to an incorrect value will not harm the
   traffic, but it may cause a circuit to be misidentified and thereby
   create difficulties for service personnel when attempting to
   troubleshoot a problem:

      dsx1CircuitIdentifier

   Setting the following object can cause an increase in the number of
   traps received by the network management station:

      dsx1LineStatusChangeTrapEnable

   The readable objects in this MIB module (i.e., the objects with a
   MAX-ACCESS other than not-accessible) may be considered sensitive in
   some environments since, collectively, they provide extensive
   information about the performance of interfaces in DS1/J1/E1/DS2/E2
   equipment or networks and can reveal some aspects of their

Top      Up      ToC       Page 84 
   configuration.  In such environments, it is important to control even
   GET and NOTIFY access to these objects and possibly to encrypt the
   values of these objects when sending them over the network via SNMP.

   SNMP versions prior to SNMPv3 did not include adequate security.
   Even if the network itself is secure (for example by using IPSec),
   even then, there is no control as to who on the secure network is
   allowed to access and GET/SET (read/change/create/delete) the objects
   in this MIB module.

   It is RECOMMENDED that implementers consider the security features as
   provided by the SNMPv3 framework (see [RFC3410], section 8),
   including full support for the SNMPv3 cryptographic mechanisms (for
   authentication and privacy).

   Further, deployment of SNMP versions prior to SNMPv3 is NOT
   RECOMMENDED.  Instead, it is RECOMMENDED to deploy SNMPv3 and to
   enable cryptographic security.  It is then a customer/operator
   responsibility to ensure that the SNMP entity giving access to an
   instance of this MIB module is properly configured to give access to
   the objects only to those principals (users) that have legitimate
   rights to indeed GET or SET (change/create/delete) them.

6.  Acknowledgments

   This document was produced by the AToM MIB Working Group.

7.  References

7.1.  Normative References

   [RFC2119]       Bradner, S., "Key words for use in RFCs to Indicate
                   Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2578]       McCloghrie, K., Perkins, D., and J. Schoenwaelder,
                   "Structure of Management Information Version 2
                   (SMIv2)", STD 58, RFC 2578, April 1999.

   [RFC2579]       McCloghrie, K., Perkins, D., and J. Schoenwaelder,
                   "Textual Conventions for SMIv2", STD 58, RFC 2579,
                   April 1999.

   [RFC2580]       McCloghrie, K., Perkins, D., and J. Schoenwaelder,
                   "Conformance Statements for SMIv2", STD 58, RFC 2580,
                   April 1999.

   [RFC2863]       McCloghrie, K. and F. Kastenholz, "The Interfaces
                   Group MIB", RFC 2863, June 2000.

Top      Up      ToC       Page 85 
   [AT&T-TR-54016] AT&T Technical Reference, Requirements for
                   Interfacing Digital Terminal Equipment to Services
                   Employing the Extended Superframe Format, Publication
                   54016, May 1988.

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

   [CCITT-G.703]   ITU-T G.703, Physical/Electrical Characteristics of
                   Hierarchical Digital Interfaces, November 2001.

   [ITU-T-G.704]   ITU-T G.704: Synchronous frame structures used at
                   1544, 6312, 2048, 8488 and 44 736 kbit/s Hierarchical
                   Levels, October 1998.

   [ANSI-T1.231]   American National Standard for Telecommunications --
                   Digital Hierarchy DS1-- Layer 1 In-Service Digital
                   Transmission Performance Monitoring, T1.231.02,
                   October 2003.

   [ITU-T-O.162]   ITU-T O.162, Equipment To Perform In Service
                   Monitoring On 2048 kbit/s Signals, October 1992.

   [CCITT-G.821]   ITU-T G.821, Error Performance Of An International
                   Digital Connection Forming Part Of An Integrated
                   Services Digital Network, December 2002.

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

   [CCITT-G.706]   ITU-T G.706, Frame Alignment and Cyclic Redundancy
                   Check (CRC) Procedures Relating to Basic Frame
                   Structures Defined in Recommendation G.704, April
                   1991.

   [CCITT-G.732]   ITU-T G.732, Characteristics Of Primary PCM Multiplex
                   Equipment Operating at 2048 kbit/s, November 1988.

   [ITU-T-G.775]   ITU-T G.775: Loss of signal (LOS) and alarm
                   indication signal (AIS) defect detection and
                   clearance criteria, October 1998.

   [ITU-T-G.826]   ITU-T G.826: Error performance parameters and
                   objectives for international, constant bit rate
                   digital paths at or above the primary rate, December
                   2002.

Top      Up      ToC       Page 86 
   [ANSI-T1.107]   American National Standard for Telecommunications --
                   Digital Hierarchy - Format Specifications, T1.107,
                   January 2002.

   [RFC3593]       Tesink, K., "Textual Conventions for MIB Modules
                   Using Performance History Based on 15 Minute
                   Intervals", RFC 3593, September 2003.

   [ITU-T-M.1400]  ITU-T M.1400: Designation For Interconnections Among
                   Network Operators, October 2001.

   [JT-G704]       JT-G.704: Synchronous frame structures used at
                   Primary and Secondary Hierarchical Levels, 2002.

   [JT-G706]       JT-G.706: Frame Alignment and Cyclic Redundancy Check
                   (CRC) Procedures.

   [JT-I431]       JT-I.431: ISDN Primary Rate User-Network
                   Interface,Layer 1 Specifications, 2002.

7.2.  Informative References

   [RFC1213]       McCloghrie, K. and M. Rose, "Management Information
                   Base for Network Management of TCP/IP-based
                   internets:MIB-II", STD 17, RFC 1213, March 1991.

   [RFC3895]       Nicklass, O., "Definitions of Managed Objects for the
                   DS1, E1, DS2, and E2 Interface Types", RFC 3895,
                   September 2004.

   [RFC2495]       Fowler, D., "Definitions of Managed Objects for the
                   DS1, E1, DS2 and E2 Interface Types", RFC 2495,
                   January 1999.

   [RFC1406]       Baker, F. and J. Watt, "Definitions of Managed
                   Objects for the DS1 and E1 Interface Types", RFC
                   1406, January 1993.

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

   [RFC3896]       Nicklass, O., "Definitions of Managed Objects for the
                   DS3/E3 Interface Type", RFC 3896, September 2004.

Top      Up      ToC       Page 87 
   [RFC3592]       Tesink, K., "Definitions of Managed Objects for the
                   Synchronous Optical Network/Synchronous Digital
                   Hierarchy (SONET/SDH) Interface Type", RFC 3592,
                   September 2003.

   [RFC2494]       Fowler, D., "Definitions of Managed Objects for the
                   DS0 and DS0 Bundle Interface Type", RFC 2494, January
                   1999.

   [ANSI-T1.102]   American National Standard for Telecommunications --
                   Digital Hierarchy - Electrical Interfaces, T1.102,
                   December 1993.

   [RFC3410]       Case, J., Mundy, R., Partain, D., and B. Stewart,
                   "Introduction and Applicability Statements for
                   Internet-Standard Management Framework", RFC 3410,
                   December 2002.

Top      Up      ToC       Page 88 
Appendix A - Use of dsx1IfIndex and dsx1LineIndex

   This appendix exists to document the previous use of dsx1IfIndex and
   dsx1LineIndex and to clarify the relationship of dsx1LineIndex as
   defined in RFC 1406 with the dsx1LineIndex as defined in this
   document.

   The following shows the old and new definitions and the relationship:

   [New Definition]: "This object should be made equal to ifIndex.  The
   next paragraph describes its previous usage.  Making the object equal
   to ifIndex allows proper use of ifStackTable and ds0/ds0bundle mibs.

   [Old Definition]: "This object is the identifier of 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 that is
   greater than ifNumber and numbering the inside interfaces (e.g.,
   equipment side) with even numbers and outside interfaces (e.g.,
   network side) with odd numbers."

   When the "Old Definition" was created, it was described this way to
   allow a manager to treat the value as if it were an ifIndex; i.e.,
   the value would be either:  1) an ifIndex value or 2) a value that
   was guaranteed to be different from all valid ifIndex values.

   The new definition is a subset of that definition; i.e., the value is
   always an ifIndex value.

   The following is Section 3.1 from RFC 1406:

      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.

Top      Up      ToC       Page 89 
      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) [RFC1213].

      External & Internal interface scenario: the SNMP Agents resides on
      a 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:

            +-----+
      |     |     |
      |     |     |               +---------------------+
      |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

Top      Up      ToC       Page 90 
      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:

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

Appendix B - The Delay Approach to Unavailable Seconds

   This procedure is illustrated below for a DS1 ESF interface.  Similar
   rules would apply for other DS1, DS2, and E1 interface variants.  The
   procedure guarantees that the statistical counters are correctly
   updated at all times, although they lag real time by 10 seconds.  At
   the end of each 15-minute interval, the current interval counts are
   transferred to the most recent interval entry and each interval is
   shifted up by one position, with the oldest being discarded if
   necessary in order to make room.  The current interval counts then
   start over from zero.  Note, however, that the signal state
   calculation does not start afresh at each interval boundary;  rather,
   signal state information is retained across interval boundaries.

Top      Up      ToC       Page 91 
+---------------------------------------------------------------------+
|               READ COUNTERS & STATUS INFO FROM HARDWARE             |
|                                                                     |
| BPV EXZ LOS FE CRC CS AIS SEF OOF LOF       RAI G1-G6 SE FE LV SL   |
+---------------------------------------------------------------------+
   |   |   |   |  |   |  |   |   |   |         |    |    |  |  |  |
   |   |   |   |  |   |  |   |   |   |         |    |    |  |  |  |
   V   V   V   V  V   V  V   V   V   V         V    V    V  V  V  V
+---------------------------------------------------------------------+
|    ACCUM ONE-SEC STATS, CHK ERR THRESHOLDS, & UPDT SIGNAL STATE     |
|                                                                     |
|  |<---------- NEAR END ----------->|    |<-------- FAR END ------>| |
|                                                                     |
|  LCV LES PCV ES CSS BES SES SEFS A/U    PCV ES CSS BES SES SEFS A/U |
+---------------------------------------------------------------------+
    |   |   |  |   |   |   |   |    |      |  |   |   |   |   |    |
    |   |   |  |   |   |   |   |    |      |  |   |   |   |   |    |
    V   V   V  V   V   V   V   V    |      V  V   V   V   V   V    |
 +------------------------------+   |    +----------------------+  |
 |         ONE-SEC DELAY        |   |    |    ONE-SEC DELAY     |  |
 |           (1 OF 10)          |   |    |      (1 OF 10)       |  |
 +------------------------------+   |    +----------------------+  |
   |   |   |  |   |   |   |   |     |      |  |   |   |   |   |    |
   /   /   /  /   /   /   /   /     /      /  /   /   /   /   /    /
   |   |   |  |   |   |   |   |     |      |  |   |   |   |   |    |
   V   V   V  V   V   V   V   V     |      V  V   V   V   V   V    |
 +------------------------------+   |    +----------------------+  |
 |         ONE-SEC DELAY        |   |    |    ONE-SEC DELAY     |  |
 |           (10 OF 10)         |   |    |      (10 OF 10)      |  |
 +------------------------------+   |    +----------------------+  |
   |   |   |  |   |   |   |   |     |      |  |   |   |   |   |    |
   V   V   V  V   V   V   V   V     V      V  V   V   V   V   V    V
+---------------------------------------------------------------------+
|                    UPDATE STATISTICS COUNTERS                       |
|                                                                     |
|<-------------- NEAR END ----------->| |<--------- FAR END --------->|
|                                                                     |
|LCV LES PCV ES CSS BES SES SEFS UAS DM PCV ES CSS BES SES SEFS UAS DM|
+---------------------------------------------------------------------+

   Note that if such a procedure is adopted, there is no current
   interval data for the first 10 seconds after a system comes up.
   noSuchInstance must be returned if a management station attempts to
   access the current interval counters during this time.

   It is an implementation-specific matter whether an agent assumes that
   the initial state of the interface is available or unavailable.

Top      Up      ToC       Page 92 
Appendix C - Changes from Pervious Versions

C.1.  Changes from RFC 3895

   The changes from RFC 3895 [RFC3895] are the following:

      (1) Values were added to dsx1LineType to support J1 types.
      (2) The object dsx1LineImpedance was added.
      (3) All DM-related objects were deprecated following their
          removal from ITU performance standards.
      (4) Relevant text and reference section were updated.
      (5) Changes in Compliance Statements to include new values.

C.2.  Changes from RFC 2495

   The changes from RFC 2495 [RFC2495] are the following:

      (1) The dsx1FracIfIndex SYNTAX matches the description range.
      (2) A value was added to dsx1TransmitClockSource.
      (3) Values were added to dsx1LineType.
      (4) Two objects were added, dsx1LineMode and dsx1LineBuildOut, to
          better express transceiver mode and LineBuildOut for T1.
      (5) Reference was added to Circuit Identifier object.
      (6) Align the DESCRIPTION clauses of few statistic objects with
          the near-end definition, with the far-end definition, and with
          [RFC3593].
      (7) Changes in Compliance Statements to include new objects.
      (8) A typographical error in dsx2E2 was fixed; new name is dsx1E2.

C.3.  Changes from RFC 1406

   The changes from RFC 1406 [RFC1406] are the following:

      (1) The Fractional table has been deprecated.
      (2) This document uses SMIv2.
      (3) Usage is given for ifTable and ifXTable.
      (4) Example usage of ifStackTable is included.
      (5) dsx1IfIndex has been deprecated.
      (6) Support for DS2 and E2 has been added.
      (7) Additional lineTypes for DS2, E2, and unframed E1 were added.
      (8) The definition of valid intervals has been clarified for the
          case where the agent proxied for other devices.  In
          particular, the treatment of missing intervals has been
          clarified.
      (9) An inward loopback has been added.
     (10) Additional lineStatus bits have been added for Near End in
          Unavailable Signal State, Carrier Equipment Out of Service,
          DS2 Payload AIS, and DS2 Performance Threshold.

Top      Up      ToC       Page 93 
     (11) A read-write line Length object has been added.
     (12) Signal mode of other has been added.
     (13) Added a lineStatus last change, trap and enabler.
     (14) The e1(19) ifType has been obsoleted, so this MIB does not
          list it as a supported ifType.
     (15) Textual Conventions for statistics objects have been used.
     (16) A new object, dsx1LoopbackStatus, has been introduced to
          reflect the loopbacks established on a DS1 interface and the
          source to the requests. dsx1LoopbackConfig continues to be
          the desired loopback state while dsx1LoopbackStatus reflects
          the actual state.
     (17) A dual loopback has been added to allow the setting of an
          inward loopback and a line loopback at the same time.
     (18) An object indicating which channel to use within a parent
          object (i.e., DS3) has been added.
     (19) An object has been added to indicate whether or not this
          DS1/E1 is channelized.
     (20) Line coding type of B6ZS has been added for DS2.

C.4.  Companion Documents

   This document is a companion to the documents that define managed
   objects for the DS0 [RFC2494], DS3/E3 [RFC3896], and Synchronous
   Optical Network/Synchronous Digital Hierarchy (SONET/SDH) [RFC3592]
   Interface Types.

Author's Address

   Orly Nicklass, Editor
   RAD Data Communications, Ltd.
   Ziv Tower, 24 Roul Walenberg
   Tel Aviv, Israel, 69719

   Phone: 9723-765-9969
   EMail: orly_n@rad.com

Top      Up      ToC       Page 94 
Full Copyright Statement

   Copyright (C) The IETF Trust (2007).

   This document is subject to the rights, licenses and restrictions
   contained in BCP 78, and except as set forth therein, the authors
   retain all their rights.

   This document and the information contained herein are provided on an
   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND
   THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS
   OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
   THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
   WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Intellectual Property

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
   might or might not be available; nor does it represent that it has
   made any independent effort to identify any such rights.  Information
   on the procedures with respect to rights in RFC documents can be
   found in BCP 78 and BCP 79.

   Copies of IPR disclosures made to the IETF Secretariat and any
   assurances of licenses to be made available, or the result of an
   attempt made to obtain a general license or permission for the use of
   such proprietary rights by implementers or users of this
   specification can be obtained from the IETF on-line IPR repository at
   http://www.ietf.org/ipr.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights that may cover technology that may be required to implement
   this standard.  Please address the information to the IETF at
   ietf-ipr@ietf.org.

Acknowledgement

   Funding for the RFC Editor function is currently provided by the
   Internet Society.