MPLS Working Group                                              Chen  Li
Internet-Draft                                              Lianyuan  Li
Intended status: Standards Track                               Lu  Huang
Expires: September 12, 2012                                 China Mobile
                                                             Emily  Chen
                                                           Quintin  Zhao
                                                     Huawei Technologies
                                                          March 11, 2012


        Management Information Base for MPLS LDP Multi Topology
                      draft-li-mpls-ldp-mt-mib-02

Abstract

   This memo defines an portion of the Management Information Base (MIB)
   for use with network management protocols in the Internet community.
   In particular, it describes a MIB module for Multi-Topology Networks
   over Multi-protocol Label Switching(MPLS) Label Switching
   Routers(LSRs).

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on September 12, 2012.

Copyright Notice

   Copyright (c) 2011 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect



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   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  The Internet-Standard Management Framework . . . . . . . . . .  3
   3.  Overview of MT-MPLS-STD-MIB objects  . . . . . . . . . . . . .  3
   4.  MPLS-LDP-MT-STD-MIB Module Definitions . . . . . . . . . . . .  5
   5.  Security Considerations  . . . . . . . . . . . . . . . . . . . 16
   6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 16
   7.  Normative References . . . . . . . . . . . . . . . . . . . . . 16
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16



































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1.  Introduction

   There are increasing requirements to support multi-topology in MPLS
   network.  For example, service providers want to assign different
   level of service(s) to different topologies so that the service
   separation can be achieved.  It is also possible to have an in-band
   management network on top of the original MPLS topology, or maintain
   separate routing and MPLS domains for isolated multicast or IPv6
   islands within the backbone, or force a subset of an address space to
   follow a different MPLS topology for the purpose of security, QoS or
   simplified management and/or operations.

   For a detailed overview of the multi topology, please refer to
   [I-D.ietf-mpls-ldp-multi-topology].


2.  The Internet-Standard Management Framework

   For a detailed overview of the documents that describe the current
   Internet-Standard Management Framework, please refer to section 7 of
   RFC 3410[RFC3410] .  Managed objects are accessed via a virtual
   information store, termed the Management Information Base or MIB.
   MIB objects are generally accessed through the Simple Network
   Management Protocol (SNMP).  Objects in the MIB are defined using the
   mechanisms defined in the Structure of Management Information (SMI).
   This memo specifies a MIB module that is compliant to the SMIv2,
   which is described in STD 58, RFC 2578[RFC2578], STD 58, RFC
   2579[RFC2579] and STD 58, RFC 2580[RFC2580].


3.  Overview of MT-MPLS-STD-MIB objects

   The following subsections describe the purpose of each of the objects
   contained in the MT-MPLS-STD-MIB.

   3.1.  MPLS LDP MT Entity Table

   The mplsLdpEntityTable specificed in [RFC3815] is used to configure
   information which is used by the LDP protocol to setup potential LDP
   Sessions.  The mplsLdpMtEntityTable can be considered as an extention
   to mplsLdpEntityTable to setup potential LDP MT Sessions.

   Each entry/row in this table represents a single LDP MT Entity.
   There is no maximum number of LDP MT Entities specified.  However,
   there is an mplsLdpMtEntityIndexNext object which should be retrieved
   by the command generator prior to creating an LDP MT Entity.  If the
   mplsLdpMtEntityIndexNext object is zero, this indicates that the LSR/
   LER is not able to create another LDP MT Entity at that time.



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   3.2.  MPLS LDP MT Session Table

   Since all the MT related label messages can be advertised by LDP
   Sessions in default topology, there is no need to create extra tcp
   connection for Multi Topology.

   The mplsLdpMtSessionTable is a read-only table.  Each entry in this
   table represents an MT Session which is related to one or more LDP MT
   Entities and only one LDP Session in default topology.

   3.3.  MPLS LDP MT LSP Table

   The Label Information Base (LIB) contains information about labels
   learned by the LSR.  The LIB for LDP and MPLS-RSVP (i.e., all
   currently defined MPLS protocols) is represented in the LSR MIB
   [RFC3813].  The LIB is represented by the LSR MIB's mplsXCTable (mpls
   Cross Connect Table), mplsInSegmentTable (mpls In Segment Table) and
   the mplsOutSegmentTable (mpls Out Segment Table).  The mplsXCTable
   models the cross-connection of the incoming label with a specific
   outgoing label.

   In Multi Topology network, the MT-ID is used during LDP advertisement
   to identify an LSP in specified topology.

   3.4.  MT statistics Table

   MTStatisticsTable is a read-only table which contains statistical
   information related to packet passing through the LSP under the
   topology.  The statistical information includes packets total counts,
   delay, jitter and so on.

   3.5 MPLS LDP MT Notifications

   The mplsLdpMtSessionUp and mplsLdpMtSessionDown notifications are



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   generated when there is an appropriate change in the
   mplsLdpMtSessionState object, e.g., when sessions change state (Up to
   Down for the mplsLdpMtSessionDown notification, or Down to Up for the
   mplsLdpMtSessionUp notification).


4.  MPLS-LDP-MT-STD-MIB Module Definitions
   MPLS-LDP-MT-STD-MIB DEFINITIONS ::= BEGIN

   IMPORTS
        OBJECT-TYPE, MODULE-IDENTITY, NOTIFICATION-TYPE,
        Counter32, Unsigned32
                FROM SNMPv2-SMI                         -- [RFC2578]

        MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
                FROM SNMPv2-CONF                        -- [RFC2580]

        RowStatus, TimeStamp, StorageType
                FROM SNMPv2-TC                          -- [RFC2579]

        InetAddressPrefixLength,
        InetAddress
                FROM INET-ADDRESS-MIB                   -- [RFC4001]

        IndexInteger,
        IndexIntegerNextFree
                FROM DIFFSERV-MIB                       -- [RFC3289]

        MplsLdpIdentifier,
                FROM MPLS-TC-STD-MIB                    -- [RFC3811]

        MplsLdpMtStdMIB MODULE-IDENTITY
        LAST-UPDATED "20120228" -- Feb 28, 2012
        CONTACT-INFO
           "To be added"
        DESCRIPTION
           "This MIB contains managed object definitions for the 'Multiprotocol
           Label Switching, Label Distribution Protocol, Multi Topology'
           document."
        ::= { mplsStdMIB 9 }

    --****************************************************************

    mplsLdpMtNotifications OBJECT IDENTIFIER ::= { MplsLdpMtStdMIB 0 }
    mplsLdpMtObjects       OBJECT IDENTIFIER ::= { MplsLdpMtStdMIB 1 }






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    --****************************************************************
    -- MPLS LDP Objects
    --****************************************************************

    mplsLdpMtEntityObjects  OBJECT IDENTIFIER ::= { mplsLdpMtObjects 1 }


    mplsLdpMtSessionObjects OBJECT IDENTIFIER ::= { mplsLdpMtObjects 2 }
    mplsLdpMtLspObjects     OBJECT IDENTIFIER ::= { mplsLdpMtObjects 3 }

    --
    -- The MPLS Label Distribution Protocol Multi Topology Entity Objects
    --

    mplsLdpMtEntityLastChange OBJECT-TYPE
        SYNTAX        TimeStamp
        MAX-ACCESS    read-only
        STATUS        current
        DESCRIPTION
            "The value of sysUpTime at the time of the most
            recent addition or deletion of an entry
            to/from the mplsLdpMtEntityTable, or
            the most recent change in value of any objects in the
            mplsLdpMtEntityTable.

            If no such changes have occurred since the last
            re-initialization of the local management subsystem,
            then this object contains a zero value."
        ::= { mplsLdpMtEntityObjects 1 }

     mplsLdpMtEntityIndexNext  OBJECT-TYPE
        SYNTAX         IndexIntegerNextFree
        MAX-ACCESS     read-only
        STATUS         current
        DESCRIPTION
            "This object contains an appropriate value to
            be used for mplsLdpEntityIndex when creating
            entries in the mplsLdpEntityTable. The value
            0 indicates that no unassigned entries are
            available."
       ::= { mplsLdpMtEntityObjects 2 }

     mplsLdpMtEntityTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF mplsLdpMtEntityEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "This table contains information about the


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            MPLS Label Distribution Protocol Multi Topology
            Entities which exist on this Label Switching
            Router (LSR) or Label Edge Router (LER)."
         ::= { mplsLdpMtEntityObjects 3 }

     -- MPLS LDP MT Entity Table

     mplsLdpMtEntityEntry OBJECT-TYPE
         SYNTAX      mplsLdpMtEntityEntry
         MAX-ACCESS  not-accessible
         STATUS      current
         DESCRIPTION
           "An entry in this table represents an LDP MT entity.  An entry can be
           created by a network administrator or by an SNMP agent as instructed
           by LDP."
         INDEX       {  mplsLdpMtEntityLdpId, mplsLdpMtEntityIndex  }
         ::= { mplsLdpMtEntityTable 1 }

    mplsLdpMtEntityEntry ::= SEQUENCE {
        mplsLdpMtEntityLdpId                MplsLdpIdentifier,
        mplsLdpMtEntityMtId                 Unsigned32,
        mplsLdpMtEntityIndex                IndexInteger,
        mplsLdpMtEntityAdminStatus          INTEGER,
        mplsLdpMtEntityStorageType          StorageType,
        mplsLdpMtEntityRowStatus            RowStatus
        }

    mplsLdpMtEntityLdpId OBJECT-TYPE
        SYNTAX      MplsLdpIdentifier
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "The LDP identifier."
        REFERENCE
            "RFC5036, LDP Specification, Section on LDP Identifiers."
        ::= { mplsLdpMtEntityEntry 1 }

   mplsLdpMtEntityMtId OBJECT-TYPE
        SYNTAX      Unsigned32
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "The Multi Topology identifier of this LDP MT Entity."
        DEFVAL { 0 }
        ::= { mplsLdpMtEntityEntry 2 }


    mplsLdpMtEntityIndex OBJECT-TYPE
        SYNTAX      IndexInteger


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        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
           "This index is used as a secondary index to uniquely identify this
           row.  Before creating a row in this table, the
           'mplsLdpMtEntityIndexNext' object should be retrieved.  That value
           should be used for the value of this index when creating a row in
           this table.  NOTE: if a value of zero (0) is retrieved, that
           indicates that no rows can be created in this table at this time."
        ::= { mplsLdpMtEntityEntry 3 }

    mplsLdpMtEntityAdminStatus OBJECT-TYPE
        SYNTAX      INTEGER {
                      enable(1),
                      disable(2)
                    }
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
           "The administrative status of this LDP MT Entity.  If this object is
           changed from 'enable' to 'disable' and this entity has already
           attempted to establish contact with a MT Session, then all contact
           with that MT Session is lost and all information from that MT Session
           needs to be removed from the MIB.  (This implies that the network
           management subsystem should clean up any related entry in the
           mplsLdpMtSessionTable.).  At this point the operator is able to
           change values which are related to this entity.  When the admin
           status is set back to 'enable', then this MT Entity will attempt to
           establish a new MT Session."
        DEFVAL  { enable }
        ::= { mplsLdpMtEntityEntry 4 }

    mplsLdpMtEntityStorageType  OBJECT-TYPE
        SYNTAX      StorageType
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
           "The storage type for this conceptual row.  Conceptual rows having
           the value 'permanent(4)' need not allow write-access to any columnar
           objects in the row."
        DEFVAL{ nonVolatile }
        ::= { mplsLdpMtEntityEntry 5 }

    mplsLdpMtEntityRowStatus OBJECT-TYPE
        SYNTAX      RowStatus
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION



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           "The status of this conceptual row.  All writable objects in this row
           may be modified at any time, however, as described in detail in the
           section entitled, 'Changing Values After Session Establishment', and
           again described in the DESCRIPTION clause of the
           mplsLdpMtEntityAdminStatus object, if a session has been initiated
           with a Peer, changing objects in this table will wreak havoc with the
           session and interrupt traffic.  To repeat again: the recommended
           procedure is to set the mplsLdpMtEntityAdminStatus to down, thereby
           explicitly causing a session to be torn down.  Then, change objects
           in this entry, then set the mplsLdpMtEntityAdminStatus to enable,
           which enables a new session to be initiated."
        ::= { mplsLdpMtEntityEntry 6 }


   -- MPLS LDP MT Session Table

   mplsLdpMtSessionLastChange OBJECT-TYPE
        SYNTAX          TimeStamp
        MAX-ACCESS      read-only
        STATUS          current
        DESCRIPTION
            "The value of sysUpTime at the time of the most
            recent addition or deletion to/from the
            mplsLdpMtSessionTable."
        ::= { mplsLdpMtSessionObjects 1 }

   mplsLdpMtSessionTable OBJECT-TYPE
        SYNTAX SEQUENCE OF mplsLdpMtSessionEntry
        MAX-ACCESS not-accessible
        STATUS current
        DESCRIPTION
           "A table of MT Sessions between the LDP MT Entities.  Each row in
           this table represents a single MT session."
        ::= { mplsLdpMtSessionObjects 2 }

   mplsLdpMtSessionEntry OBJECT-TYPE
        SYNTAX          mplsLdpMtSessionEntry
        MAX-ACCESS      not-accessible
        STATUS          current
        DESCRIPTION
           "An entry in this table represents information on a single MT
           session.  The information contained in a row is read-only."
        ::= { mplsLdpMtSessionTable 1 }

   mplsLdpMtSessionEntry ::= SEQUENCE {
        mplsLdpSessionState               INTEGER,
        mplsLdpMtSessionStateLastChange   TimeStamp,
        mplsLdpMtSessionMtId              Unsigned32
        }


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   mplsLdpMtSessionState OBJECT-TYPE
        SYNTAX  INTEGER {
                    initialized(1),
                    operational(2)
                }
        MAX-ACCESS read-only
        STATUS     current
        DESCRIPTION
           "The current state of the MT Session.  When the tcp connection in
           default topology is established, and both ends have the capability of
           the given MT-ID, the state can change from initialized to
           operational."
        ::= { mplsLdpMtSessionEntry 1 }

   mplsLdpMtSessionStateLastChange OBJECT-TYPE
        SYNTAX     TimeStamp
        MAX-ACCESS read-only
        STATUS     current
        DESCRIPTION
           "The value of sysUpTime at the time this MT Session was created."
        ::= { mplsLdpMtSessionEntry 2 }

   mplsLdpMtSessionMtId OBJECT-TYPE
        SYNTAX     Unsigned32
        MAX-ACCESS read-create
        STATUS     current
        DESCRIPTION
           "The Multi Topology identifier of this LDP MT Session."
        DEFVAL { 0 }
        ::= { mplsLdpMtSessionEntry 3 }

   -- MT LDP LSP Table

   mplsLdpMtLspLastChange OBJECT-TYPE
        SYNTAX          TimeStamp
        MAX-ACCESS      read-only
        STATUS          current
        DESCRIPTION
            "The value of sysUpTime at the time of the most
            recent addition/deletion of an entry
            to/from the mplsLdpMtLspTable or
            the most recent change in values to any objects
            in the mplsLdpMtLspTable.

            If no such changes have occurred since the last
            re-initialization of the local management subsystem,
            then this object contains a zero value."



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       ::= { mplsLdpMtLspObjects 1 }

   mplsLdpMtLspNext  OBJECT-TYPE
        SYNTAX         IndexIntegerNextFree
        MAX-ACCESS     read-only
        STATUS         current
        DESCRIPTION
            "This object contains an appropriate value to
            be used for mplsLdpMtLspIndex when creating
            entries in the mplsLdpMtLspTable. The value
            0 indicates that no unassigned entries are
            available."
       ::= { mplsLdpMtLspObjects 2 }

   mplsLdpMtLspTable OBJECT-TYPE
        SYNTAX     SEQUENCE OF mplsLdpMtLspEntry
        MAX-ACCESS not-accessible
        STATUS     current
        DESCRIPTION
           "This table specifies MT LIB label switching information.  Entries in
           this table define LIB label switching entries associated with the
           specified topology."
        ::= { mplsLdpMtLspObjects 3 }

   mplsLdpMtLspEntry OBJECT-TYPE
        SYNTAX       mplsLdpMtLspEntry
        MAX-ACCESS   not-accessible
        STATUS       current
        DESCRIPTION
           "An entry in this table is created by an LSR for every label within
           the context of a specific topology capable of supporting MT LDP LSP.
           The indexing provides an ordering of topologies per interface."
        INDEX { mplsLdpMtLspIndex }
        ::= { mplsLdpMtLspTable 1 }

   mplsLdpMtLspEntry ::= SEQUENCE {
        mplsLdpMtLspIndex               IndexInteger,
        mplsLdpMtLspMtId                Unsigned32,
        mplsLdpMtLspFecAddr             InetAddress,
        mplsLdpMtLspFecAddrLength       InetAddressPrefixLength,
        mplsLdpMtLspStorageType         StorageType,
        mplsLdpMtLspRowStatus           RowStatus
        }

   mplsLdpMtLspIndex OBJECT-TYPE
        SYNTAX      IndexInteger
        MAX-ACCESS  not-accessible
        STATUS      current



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        DESCRIPTION
            "The index which uniquely identifies this entry."
        ::= { mplsLdpMtLspEntry 1 }

   mplsLdpMtLspMtId OBJECT-TYPE
        SYNTAX     Unsigned32
        MAX-ACCESS read-create
        STATUS     current
        DESCRIPTION
           "The Multi Topology identifier of this LDP MT LSP."
        DEFVAL { 0 }
        ::= { mplsLdpMtLspEntry 2 }

   mplsLdpMtLspFecAddr OBJECT-TYPE
        SYNTAX          InetAddress
        MAX-ACCESS      read-create
        STATUS          current
        DESCRIPTION
           "The FEC address of this LDP MT LSP. Note that the
            value of this object is interpreted as prefix address."
        REFERENCE
            "RFC5036, Section 3.4.1 FEC TLV."
        ::= { mplsLdpMtLspEntry 3 }

   mplsLdpMtLspFecAddrLength  OBJECT-TYPE
        SYNTAX      InetAddressPrefixLength
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
           "The FEC prefix length of this LDP MT LSP."
        REFERENCE
            "RFC5036, Section 3.4.1. FEC TLV."
        DEFVAL { 0 }
        ::= { mplsLdpMtLspEntry 4 }

   mplsLdpMtLspStorageType  OBJECT-TYPE
        SYNTAX      StorageType
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "The storage type for this conceptual row.
            Conceptual rows having the value 'permanent(4)'
            need not allow write-access to any columnar
            objects in the row."
        DEFVAL { nonVolatile }
        ::= { mplsLdpMtLspEntry 5 }

   mplsLdpMtLspRowStatus OBJECT-TYPE



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        SYNTAX      RowStatus
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "The status of this conceptual row.  If the value of this
            object is 'active(1)', then none of the writable objects
            of this entry can be modified, except to set this object
            to 'destroy(6)'.

            NOTE: if this row is being referenced by any entry in
            the mplsLdpLspFecTable, then a request to destroy
            this row, will result in an inconsistentValue error."
        ::= { mplsLdpMtLspEntry 7 }

   -- MT LDP LSP Statistics Table

   mplsLdpMtLspStatTable OBJECT-TYPE
        SYNTAX       SEQUENCE OF mplsLdpMtLspStatEntry
        MAX-ACCESS   not-accessible
        STATUS       current
        DESCRIPTION
           "This table contains statistical information related to packet
           passing through the LSP under the topology."
        ::= { mplsLdpMtLspObjects 4 }

   mplsLdpMtLspStatEntry OBJECT-TYPE
        SYNTAX       MTLdpLspStatTableEntry
        MAX-ACCESS   not-accessible
        STATUS       current
        DESCRIPTION
           "Each entry in the table contains information of a specific MT LDP
           LSP.  The indexing provides an ordering of LSPes per interface."
        INDEX { mplsLdpMtLspIndex }
        ::= { mplsLdpMtLspStatTable 1 }

   mplsLdpMtLspStatEntry ::= SEQUENCE {
        mplsLdpMtLspStatStartTime   TimeStamp,
        mplsLdpMtLspStatPackets     Counter32
        }

   mplsLdpMtLspStatStartTime OBJECT-TYPE
        SYNTAX          TimeStamp
        MAX-ACCESS      read-only
        STATUS          current
        DESCRIPTION
            "The value of sysUpTime at the time statistics began."
        ::= { mplsLdpMtLspStatEntry 1 }




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   mplsLdpMtLspStatPackets Counter32
        MAX-ACCESS      read-only
        STATUS          current
        DESCRIPTION
           "The number of packets which have passed through a specific
           MT LDP LSP."
        ::= { mplsLdpMtLspStatEntry 2 }

   -- Notifications

   mplsLdpMtSessionUp NOTIFICATION-TYPE
        OBJECTS {
                mplsLdpMtSessionState,
                mplsLdpMtSessionMtId
                }
        STATUS current
        DESCRIPTION
           "If this notification is sent when the value of
           'mplsLdpMtSessionState' enters the 'operational(2)' state."
        ::= { mplsLdpMtNotifications 1 }

   mplsLdpMtSessionDown NOTIFICATION-TYPE
        OBJECTS {
                mplsLdpMtSessionState,
                mplsLdpMtSessionMtId
                }
        STATUS current
        DESCRIPTION
           "This notification is sent when the value of 'mplsLdpMtSessionState'
           leaves the 'operational(2)' state."
        ::= { mplsLdpNotifications 2 }

   END

5.  Security Considerations

   It needs to be further identified.


6.  IANA Considerations

   It is no necessary to request new IANA code in the draft.


7.  Normative References

   [RFC3813] C. Srinivasan, Bloomberg L.P., A. Viswanathan,T. Nadeau,
   "MPLS/BGP Layer 3 Virtual Private Network (VPN) Management



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   Information Base", RFC 3813, June 2004.

   [RFC3815] J. Cucchiara and H. Sjostrand ,"Definitions of Managed
   Objects for the Multiprotocol Label Switching (MPLS),Label
   Distribution Protocol (LDP)",RFC 3815,June 2004.

   [RFC3814] C. Srinivasan, Bloomberg L.P., A.
   Viswanathan,"Multiprotocol Label Switching (MPLS) Forwarding
   Equivalence Class To Next Hop Label Forwarding Entry (FEC-To-NHLFE)
   Management Information Base (MIB)", RFC 3814, June 2004.

   [RFC5036] L. Andersson,I. Minei,B. Thomas,"LDP Specification",October
   2007

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


Authors' Addresses

   Chen Li
   China Mobile
   Unit2, Dacheng Plaza, No. 28 Xuanwumenxi Ave, Xuanwu District
   Beijing  100053
   P.R. China

   Email: lichenyj@chinamobile.com


   Lianyuan Li
   China Mobile
   Unit2, Dacheng Plaza, No. 28 Xuanwumenxi Ave, Xuanwu District
   Beijing  100053
   P.R. China

   Email: lilianyuan@chinamobile.com

   Lu Huang
   China Mobile
   Unit2, Dacheng Plaza, No. 28 Xuanwumenxi Ave, Xuanwu District
   Xunwu District, Beijing  100053
   China

   Email: huanglu@chinamobile.com


   Emily Chen
   Huawei Technologies


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Internet-Draft             MIB for MPLS LDP MT                 March 2012



   2330 Central Expressway
   Santa Clara, CA  95050
   US

   Email: emily.chenying@huawei.com


   Quintin Zhao
   Huawei Technologies
   125 Nagog Technology Park
   Acton, MA  01719
   US

   Email: qzhao@huawei.com




































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