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Versions: (draft-nadeau-mpls-mgmt-overview) 00 01 02 03 04 05 06 07 08 09 RFC 4221

Network Working Group                                Thomas D. Nadeau
Internet Draft                                    Cisco Systems, Inc.
Category: Informational
Expires: June 2002                                  Cheenu Srinivasan
                                                Parama Networks, Inc.

                                                        Adrian Farrel
                                                 Movaz Networks, Inc.

                                                        December 2001


   Multiprotocol Label Switching (MPLS) Management Overview

             draft-ietf-mpls-mgmt-overview-01.txt


Status of this Memo

   This document is an Internet-Draft and is in full
   conformance with all provisions of Section 10 of RFC 2026
   [RFC2026].

   Internet-Drafts are working documents of the Internet
   Engineering Task Force (IETF), its areas, and its working
   groups.  Note that other groups may also distribute working
   documents as Internet-Drafts.

   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."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt.

   The list of Internet-Draft Shadow Directories can be
   accessed at http://www.ietf.org/shadow.html.

Abstract

   This memo describes the Multiprotocol Label Switching
   (MPLS) management architecture and the inter-relationships
   between the different management information bases (MIBs)
   used for MPLS network management.


Table of Contents

  1. Introduction ..............................................  2
  2. Terminology ...............................................  3
  3. The SNMP Management Framework .............................  3
  4. MPLS Related MIBs and Inter-Relationships .................  3



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   4.1. Structure of the MPLS MIB OID Tree .....................  4
   4.2. MPLS-TC-MIB ............................................  4
   4.3. MPLS-LSR-MIB ...........................................  4
    4.3.1. Dependencies ........................................  5
   4.4. MPLS-LDP-MIB ...........................................  5
    4.4.1. Dependencies ........................................  5
   4.5. MPLS-TE-MIB ............................................  5
    4.5.1. Dependencies ........................................  6
   4.6. MPLS-FTN-MIB ...........................................  6
    4.6.1. Dependencies ........................................  6
   4.7. MPLS-LINK-BUNDLING-MIB .................................  6
    4.7.1. Dependencies ........................................  6
  5. Dependencies on Other IETF Working Groups .................  6
   5.1. pwe3 Working Group MIBs ................................  7
   5.2. ppvpn Working Group MIBs ...............................  7
    5.2.1. PPVPN-MPLS-VPN-MIB ..................................  7
   5.3. ccamp Working Group MIBs ...............................  7
   5.4. tewg MIBs ..............................................  8
  6. Security Considerations ...................................  8
  7. References ................................................  8
  8. Authors' Addresses ........................................ 10
  9. Full Copyright Statement .................................. 11



1. Introduction

   This memo describes the  Management Architecture for Multi-
   Protocol Label Switching (MPLS) [RFC3031]. In particular,
   it describes how the managed objects defined in various
   MPLS related Management Information Base (MIB) documents
   model different aspects of MPLS. Furthermore, this document
   explains the interactions and dependencies between each of
   these documents. It also includes a brief note on MIBs
   produced by the Pseudo Wire Emulation Edge to Edge (pwe3),
   Provider Provisioned Virtual Private Network (ppvpn),
   Common Control and Measurement Plane (ccamp), and Internet
   Traffic Engineering (tewg) working groups.

   This draft does not propose any additions to the MPLS MIB
   framework, nor define any standards for the Internet
   community.  It is an informational draft.

   Comments should be made directly to the MPLS mailing list
   at mpls@uu.net.




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2. Terminology

   This document uses terminology from the MPLS architecture
   document [RFC3031] and the following MPLS related MIBs:
   MPLS-TC-MIB [TCMIB], MPLS-LSR-MIB [LSRMIB], MPLS-TE-MIB
   [TEMIB], MPLS-LDP-MIB [LDPMIB], MPLS-FTN-MIB [FTNMIB], MPLS-
   LINK-BUNDLING-MIB [LBMIB], and PPVPN-MPLS-VPN-MIB [VPNMIB].


3. The SNMP Management Framework

   The SNMP Management Framework presently consists of five
   major components:

   -  An overall architecture, described in RFC 2571
      [RFC2571].

   -  Mechanisms for describing and naming objects and events
      for the purpose of management.  The first version of
      this Structure of Management Information (SMI) is
      called SMIv1 and described in STD 16, RFC 1155
      [RFC1155], STD 16, RFC 1212 [RFC1212] and STD 16, RFC
      1215 [RFC1215].  The second version, called SMIv2, is
      described in STD 58, RFC 2578 [RFC2578], STD 58, RFC
      2579 [RFC2579] and STD 58, RFC 2580 [RFC2580].

   -  Message protocols for transferring management
      information.  The first version of the SNMP message
      protocol is called SNMPv1 and described in STD 15, RFC
      1157 [RFC1157].  A second version of the SNMP message
      protocol, which is not an Internet standards track
      protocol, is called SNMPv2c and described in RFC 1901
      [RFC1901] and RFC 1906 [RFC1906].  The third version of
      the message protocol is called SNMPv3 and described in
      RFC 1906 [RFC1906], RFC 2572 [RFC2572] and RFC 2574
      [RFC2574].

   -  Protocol operations for accessing management
      information.  The first set of protocol operations and
      associated PDU formats is described in STD 15, RFC 1157
      [RFC1157].  A second set of protocol operations and
      associated PDU formats is described in RFC 1905
      [RFC1905].

   -  A set of fundamental applications described in RFC 2573
      [RFC2573] and the view-based access control mechanism
      described in RFC 2575 [RFC2575].

   A more detailed introduction to the current SNMP Management



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   Framework can be found in RFC 2570 [RFC2570].

   Managed objects are accessed via a virtual information
   store, termed the Management Information Base or MIB.
   Objects in the MIB are defined using the mechanisms defined
   in the SMI.


4. MPLS Related MIBs and Inter-Relationships

   This section addresses the MPLS related MIBS produced by
   the MPLS working group, namely MPLS-TC-MIB, MPLS-LSR-MIB,
   MPLS-TE-MIB, MPLS-LDP-MIB, MPLS-FTN-MIB, and MPLS-LINK-
   BUNDLING-MIB. The rest of this section briefly describes
   the following:

   -  the MPLS Object Identifier (OID) tree structure and the
      position of different MPLS related MIBs on this tree;

   -  the purpose of each MIB, what it can be used for, and
      how it relates to the other MIBs.

   For each MIB there is a subsection that details the
   interdependencies between that MIB and any of the other
   MPLS MIBs.


4.1.  Structure of the MPLS MIB OID Tree

   The MPLS MIB OID tree has the following structure.

      transmission -- RFC1213-MIB [RFC1213]
        |
        +- mplsMIB (166?) -- MPLS-TC-MIB
        |    |
        |    +- mplsTCMIB (1) -- MPLS-TC-MIB
        |    |
        |    +- mplsLsrMIB (2) -- MPLS-LSR-MIB
        |    |
        |    +- mplsTeMIB (3) -- MPLS-TE-MIB
        |    |
        |    +- mplsLdpMIB (4) -- MPLS-LDP-MIB
        |    |
        |    +- mplsFTNMIB (5) -- MPLS-FTN-MIB
        ?
        +- linkBundlingMIB (TBD) -- LINK-BUNDLING-MIB

   Note: Some OID information is pending assignment by IANA
   and will be included in a later revision when this is
   available.



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4.2.  MPLS-TC-MIB

   The MPLS-TC-MIB describes textual conventions [RFC2579] and
   object identities that may be common to MPLS-related MIBs.
   For example, the textual convention for representing an
   MPLS label should be commonly represented and used by all
   MPLS-related MIBs.


4.3.  MPLS-LSR-MIB

   The MPLS-LSR-MIB describes managed objects for modeling a
   MPLS Label Switch Router (LSR). In particular, this MIB is
   used to model and manage the basic label switching behavior
   and the label forwarding information base (LFIB) of an MPLS
   LSR. In doing so, the MIB provides a view of the LSPs that
   are being switched by the LSR in question.

   This MIB is the basis for many of the MPLS MIBs, since
   basic MPLS label switching is common to all MPLS
   applications.  In general, the MPLS-LSR-MIB provides a
   model of incoming labels on MPLS-enabled interfaces being
   mapped to outgoing labels on MPLS-enabled interfaces via a
   conceptual object called an MPLS cross-connect. MPLS cross-
   connect entries and their properties are represented in the
   MPLS cross-connect table (mplsXCTable) in the LSR MIB. MPLS
   cross-connect entries are typically referred to by other
   MIBs in order to reference the underlying MPLS LSP.

   For example, the MPLS-TE-MIB models traffic engineered
   tunnels.  These tunnels map to one more underlying MPLS
   LSPs. Thus, the MPLS-TE-MIB's tunnel table
   (mplsTunnelTable) entries refer to the underlying LSP by
   pointing to entries in mplsXCTable.

4.3.1.   Dependencies

   This MIB does not directly depend upon any other MPLS MIBs.
   It does represent MPLS-enabled interfaces as entries in the
   Interfaces MIB's [RFC2863] Interfaces Table (ifTable). This
   MIB imports several textual conventions from the MPLS-TC-
   MIB.


4.4.  MPLS-LDP-MIB

   The MPLS-LDP-MIB describes managed objects used to model
   and manage the Multiprotocol Label Switching Label



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   Distribution Protocol (LDP) [RFC3036].

4.4.1.   Dependencies

   The LDP MIB has three mapping tables -
   mplsLdpSesInLabelMapTable, mplsLdpSesOutLabelMapTable and
   mplsLdpSesXCMapTable - which map the LDP MIBÆs
   representation of LDP sessions to the underlying LSR MIBÆs
   representation of the LSPs created by these sessions by
   pointing to mplsInSegmentTable, mplsOutSegmentTable and
   mplsXCTable, respectively. The LDP MIBÆs mplsXCsFecsTable
   shows the relationship between between forwarding
   equivalence classes (FECs) and cross-connect entries by
   referring to entries in the LSR MIBÆs mplsXCTable.

   This MIB also imports several textual conventions from the
   MPLS-TC-MIB.


4.5.  MPLS-TE-MIB

   The MPLS-TE-MIB describes managed objects that are used to
   model and manage MPLS Traffic Engineered (TE) Tunnels. The
   MIB is based around a table that represents TE tunnels that
   either originate at the LSR in question or traverse via or
   terminate on the LSR. Note that the later case is optional,
   as only tunnel "heads" are required to be represented. This
   MIB provides statistics and configuration objects needed
   for TE tunnels.

4.5.1.   Dependencies

   This MIB depends on the MPLS-LSR-MIB and Interfaces MIB.
   Tunnel entries in the MPLS-TE-MIBÆs mplsTunnelTable refer
   to entries in mplsXCTable in the MPLS-LSR-MIB. When MPLS TE
   tunnels are represented as interfaces, entries for such
   tunnels in mplsTunnelTable have corresponding entries in
   the Interfaces MIBÆs Interfaces Table (ifTable). This MIB
   also imports several textual conventions from the MPLS-TC-
   MIB.


4.6.  MPLS-FTN-MIB

   The MPLS-FTN-MIB describes managed objects that are used to
   model and manage the MPLS FEC-to-NHLFE mappings which take
   place at any LSR that is on the edge between an MPLS domain
   and a non-MPLS domain. On each such edge LSR, to map
   traffic from the non-MPLS domain into the MPLS domain, the
   FEC-to-NHLFE mapping objects in the MPLS-FTN-MIB must be



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   supported.  In the case of an IP-to-MPLS mapping, the FEC
   objects describe IP 5-tuples representing IP source and
   destination ranges, protocol ranges etc. Matching IP
   packets can be mapped to an NHLFE which can either be an
   MPLS LSP or an MPLS TE tunnel.

4.6.1.   Dependencies

   This MIB relies directly on the MPLS-LSR-MIB and MPLS-TE-
   MIB. FECs can be mapped to two types of NHLFEs by the MPLS-
   FTN-MIB. When the NHLFE is an LSP, the FEC-to-NHLFE mapping
   is accomplished by referring to a corresponding entry in
   mplsXCTable in the MPLS-LSR-MIB. When the NHLFE is an MPLS
   TE tunnel, this mapping is accomplished by referring to a
   corresponding entry in mplsTunnelTable in MPLS-TE-MIB.


4.7.  MPLS-LINK-BUNDLING-MIB

   The MPLS-LINK-BUNDLING-MIB describes managed objects that
   are used to model and manage the MPLS TE interfaces, as
   well as the link bundling relationships that may exist
   between those interfaces.

4.7.1.   Dependencies

   The MPLS-LINK-BUNDLING-MIB directly interacts only with the
   Interfaces MIB; it references MPLS TE interfaces that are
   modeled by entries in the Interfaces MIBÆs Interfaces Table
   (ifTable) .


5. Dependencies on Other IETF Working Groups

   This section describes the broad interactions between MIBs
   produced by the pwe3, ppvpn, and ccamp working groups and
   the MPLS MIBs.


5.1.  pwe3 Working Group MIBs

   The pwe3 working group has produced a document [PWE3FW]
   which includes a description of the framework for PWE3
   MIBs. Since the PWE3 architecture includes the use of MPLS
   as an emulated service and as a PSN service, the MPLS MIBs
   described above may be leveraged.  The pwe3 framework
   document describes the interactions between the MPLS MIBs
   and the PWE3 MIBs.





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5.2.  ppvpn Working Group MIBs

   At present, the ppvpn working group has not included a
   discussion of how the MPLS MIBs interact with the MIBs
   being produced by that working group.  The authors of this
   draft hope to make a forthcoming addition to the ppvpn
   framework document [PPVPNFW] detailing these interactions.
   At the moment, there is only a single MIB [VPNMIB] produced
   which is discussed next.

5.2.1.   PPVPN-MPLS-VPN-MIB

   The PPVPN-MPLS-VPN-MIB describes managed objects that are
   used to model and manage RFC2547bis MPLS VPNs [RFC2547Bis].
   This MIB contains tables which model virtual routing
   forwarding entries (VRFs), as well as the interfaces
   associated with those VRFs.

5.2.1.1. Position in the OID Tree

      transmission -- RFC1213-MIB
        |
        +- vpnMIB (TBD) -- PPVPN-MPLS-VPN-MIB

5.2.1.2. Dependencies

   This MIB currently has no direct dependencies to any of the
   MPLS MIBs. This MIB does model MPLS VPN interfaces as
   entries in the Interfaces MIB's Interfaces Table (ifTable).
   This MIB may be modified in the future to import textual
   conventions from the MPLS-TC-MIB.


5.3.  ccamp Working Group MIBs

   At present, there are no MIBs produced by the ccamp working
   group that interact directly with the MPLS MIBs.  However,
   in the future, the existing MPLS MIBs will need to be
   extended and augmented to facilitate the technology being
   produced by this working group. Along with any MIBs
   produced by the CCAMP working group, a seperate CCAMP
   Management Framework document is expected to be issued
   describing the relationship between these MIBs and the
   existing MPLS (and other) MIBs.


5.4.  tewg MIBs

   The tewg has produced a traffic engineering MIB [TEWGMIB]
   containing objects for monitoring traffic engineered MPLS



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   based tunnels at their ingress points. The tewg will
   produce a framework document which will include a detailed
   description of the purpose of this MIB and its relationship
   with the MPLS MIBs.


6. Security Considerations

   This document describes the inter-relationships amongst the
   different MIBs relevant to MPLS management and as such does
   not have any security implications beyond those imposed by
   these MIBs themselves.


7. References

   [TCMIB]       Nadeau, T., Cucchiara, J., Srinivasan, C,
                 Viswanathan, A. and H. Sjostrand,
                 "Definition of Textual Conventions and
                 OBJECT-IDENTITIES for Multi-Protocol Label
                 Switching (MPLS) Management", Internet Draft
                 <draft-ietf-mpls-tc-mib-03.txt>, December
                 2001.

   [LSRMIB]      Srinivasan, C., Viswanathan, A. and T.
                 Nadeau, "MPLS Label Switch Router Management
                 Information Base", Internet Draft <draft-
                 ietf-mpls-lsr-mib-08.txt>, December 2001.

   [TEMIB]       Srinivasan, C., Viswanathan, A. and T.
                 Nadeau, "MPLS Traffic Engineering Management
                 Information Base Using SMIv2", Internet
                 Draft <draft-ietf-mpls-te-mib-08.txt>,
                 December 2001.

   [FTNMIB]      Nadeau, T., Srinivasan, C., and A.
                 Viswanathan, "Multiprotocol Label Switching
                 (MPLS) FEC-To-NHLFE (FTN) Management
                 Information Base", Internet Draft <draft-
                 ietf-mpls-ftn-mib-04.txt>, December 2001.

   [LBMIB]       Dubuc, M., Dharanikota, S., Nadeau, T., J.
                 Lang, "Link Bundling Management Information
                 Base Using SMIv2", Internet Draft <draft-
                 ietf-mpls-bundle-mib-00.txt>, September
                 2001.

   [VPNMIB]      Nadeau, T., Fang, L., Van Der Linde, H.,
                 Brannon, S., Chiussi, F., Dube, J, and M.
                 Tatham, "MPLS/BGP Virtual Private Network



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                 Management Information Base Using SMIv2",
                 Internet Draft, <draft-ietf-ppvpn-mpls-vpn-
                 mib-03.txt>, November 2001.

   [PWE3FW]      Pate, P., Xiao, X., White., C., Kompella.,
                 K., Malis, A., Johnson, T., and T. Nadeau,
                 "Framework for Pseudo Wire Emulation Edge-to-
                 Edge (PWE3)", Internet Draft <draft-ietf-
                 pwe3-framework-00.txt>, September, 2001.

   [PPVPNFW]     Callon, R., Suzuki, M., Gleeson, B., Malis,
                 A., Muthukrishnan, K., Rosen, E., Sargor,
                 C., and J. Yu, "A Framework for Provider
                 Provisioned Virtual Private Networks",
                 Internet Draft <draft-ietf-ppvpn-framework-
                 01.txt>, July 2001.

   [RFC2547Bis]  Rosen, E. et al, "MPLS/BGP VPNs", Internet
                 Draft <draft-ietf-ppvpn-rfc2547bis-00.txt>,
                 July 2001.

   [TEWGMIB]     Kompella, K., "A Traffic Engineering MIB",
                 Internet Draft <draft-ietf-tewg-mib-01.txt>,
                 October 2001.

   [RFC1155]     Rose, M., and K. McCloghrie, "Structure and
                 Identification of Management Information for
                 TCP/IP-based Internets", RFC 1155, May 1990.

   [RFC1157]     Case, J., Fedor, M., Schoffstall, M., and J.
                 Davin, "Simple Network Management Protocol",
                 RFC 1157, May 1990.

   [RFC1212]     Rose, M., and K. McCloghrie, "Concise MIB
                 Definitions", RFC 1212, March 1991.

   [RFC1213]     McCloghrie, K, and M. Rose, "Management
                 Information Base for Network Management of
                 TCP/IP Based Internets", RFC 1213, March
                 1991.

   [RFC1215]     M. Rose, "A Convention for Defining Traps
                 for use with the SNMP", RFC 1215, March
                 1991.

   [RFC1901]     Case, J., McCloghrie, K., Rose, M., and S.
                 Waldbusser, "Introduction to Community-based
                 SNMPv2", RFC 1901, January 1996.

   [RFC1905]     Case, J., McCloghrie, K., Rose, M., and S.



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                 Waldbusser, "Protocol Operations for Version
                 2 of the Simple Network Management Protocol
                 (SNMPv2)", RFC 1905, January 1996.

   [RFC1906]     Case, J., McCloghrie, K., Rose, M., and S.
                 Waldbusser, "Transport Mappings for Version
                 2 of the Simple Network Management Protocol
                 (SNMPv2)", RFC 1906, January 1996.

   [RFC2026]     S. Bradner, "The Internet Standards Process
                 -- Revision 3", RFC 2026, October 1996.

   [RFC2570]     Case, J., Mundy, R., Partain, D., and B.
                 Stewart, "Introduction to Version 3 of the
                 Internet-standard Network Management
                 Framework", RFC 2570, April 1999.

   [RFC2571]     Harrington, D., Presuhn, R., and B. Wijnen,
                 "An Architecture for Describing SNMP
                 Management Frameworks", RFC 2571, April
                 1999.

   [RFC2572]     Case, J., Harrington D., Presuhn R., and B.
                 Wijnen, "Message Processing and Dispatching
                 for the Simple Network Management Protocol
                 (SNMP)", RFC 2572, April 1999.

   [RFC2573]     Levi, D., Meyer, P., and B. Stewart, "SNMPv3
                 Applications", RFC 2573, April 1999.

   [RFC2574]     Blumenthal, U., and B. Wijnen, "User-based
                 Security Model (USM) for version 3 of the
                 Simple Network Management Protocol
                 (SNMPv3)", RFC 2574, April 1999.

   [RFC2575]     Wijnen, B., Presuhn, R., and K. McCloghrie,
                 "View-based Access Control Model (VACM) for
                 the Simple Network Management Protocol
                 (SNMP)", RFC 2575, April 1999.

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

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




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

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

   [RFC3031]     Rosen, E., Viswanathan, A., and R. Callon,
                 "Multiprotocol Label Switching
                 Architecture", RFC 3031, January 2001.

   [RFC3036]     Andersson, L., Doolan, P., Feldman, N.,
                 Fredette, A., and B. Thomas, "LDP
                 Specification", RFC 3036, January 2001.


8. Authors' Addresses

  Thomas D. Nadeau
  Cisco Systems, Inc.
  300 Apollo Drive
  Chelmsford, MA 01824
  Phone: +1-978-244-3051
  Email: tnadeau@cisco.com

  Cheenu Srinivasan
  Parama Networks, Inc.
  1030 Broad Street
  Shrewsbury, NJ 07702
  Phone: +1-732-544-9120 x731
  Email: cheenu@paramanet.com

  Adrian Farrel
  Movaz Networks, Inc.
  7926 Jones Branch Drive, Suite 615
  McLean, VA 22102
  Phone: +1-703-847-9847
  Email: afarrel@movaz.com


9. Full Copyright Statement

   Copyright (C) The Internet Society (2001). All Rights
   Reserved.

   This document and translations of it may be copied and
   furnished to others, and derivative works that comment on
   or otherwise explain it or assist in its implementation may
   be prepared, copied, published and distributed, in whole or



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   in part, without restriction of any kind, provided that the
   above copyright notice and this paragraph are included on
   all such copies and derivative works.  However, this
   document itself may not be modified in any way, such as by
   removing the copyright notice or references to the Internet
   Society or other Internet organizations, except as needed
   for the purpose of developing Internet standards in which
   case the procedures for copyrights defined in the Internet
   Standards process must be followed, or as required to
   translate it into languages other than English.

   The limited permissions granted above are perpetual and
   will not be revoked by the Internet Society or its
   successors or assigns. This document and the information
   contained herein is provided on an "AS IS" basis and THE
   INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE
   DISCLAIMS 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.
































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