Network Working Group Thomas D. Nadeau Internet Draft Cisco Systems, Inc. Category: Informational Expires: November 2003 Cheenu Srinivasan Adrian Farrel Movaz Networks, Inc. June 2003 Multiprotocol Label Switching (MPLS) Management Overview draft-ietf-mpls-mgmt-overview-06.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 A range of Management Information Base (MIB) modules has been developed to help model and manage the various aspects of Multiprotocol Label Switching (MPLS) networks. These MIB modules are defined in separate documents that focus on the specific areas of responsibility of the modules that they describe. This memo describes the management architecture for MPLS and indicates the inter-relationships between the different MIB modules used for MPLS network management. Nadeau, Srinivasan and Farrel [Page 1] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 Table of Contents 1. Introduction 3 2. Terminology 3 3. The SNMP Management Framework 4 4. An Introduction to the MPLS Working Group MIB Modules 4 4.1. Structure of the MPLS MIB OID Tree 5 4.2. MPLS-TC-STD-MIB 5 4.3. MPLS-LSR-STD-MIB 5 4.4. MPLS-LDP-STD-MIB 6 4.5. MPLS-LDP-GENERIC-STD-MIB 6 4.6. MPLS-LDP-ATM-STD-MIB 6 4.7. MPLS-LDP-FRAME-RELAY-STD-MIB 7 4.8. MPLS-TE-STD-MIB 7 4.9. MPLS-FTN-STD-MIB 7 4.10. TE-LINK-STD-MIB 7 4.11. MIB Module Interdependencies 8 4.12. Dependencies on External MIB Modules 8 5. Tables, Scalars and Notifications in MPLS-LSR-STD-MIB 9 5.1. Tables 9 5.2. Scalars 10 5.3. Notifications 10 5.4. Dependencies Between MIB Module Tables 10 6. Tables, Scalars and Notifications in the LDP MIB 11 6.1. MIB Modules 11 6.2. Tables 11 6.3. Scalars 12 6.4. Notifications 12 6.5. Dependencies Between MIB Module Tables 13 7. Tables, Scalars and Notifications in MPLS-TE-STD-MIB 13 7.1. Tables 13 7.2. Scalars 14 7.3. Notifications 15 7.4. Dependencies Between MIB Module Tables 15 8. Tables, Scalars and Notifications in MPLS-FTN-STD-MIB 15 8.1. Tables 15 8.2. Scalars 16 8.3. Notifications 16 8.4. Dependencies Between MIB Module Tables 16 9. Tables and Objects in TE-LINK-STD-MIB 16 9.1. Tables 16 9.2. Scalars 17 9.3. Notifications 17 9.4. Dependencies Between MIB Module Tables 17 10. Table Dependencies Between MPLS MIB Modules 18 11. A Note on Interfaces 18 11.1. MPLS Tunnels as Interfaces 18 11.2. Application of the Interfaces Group to TE Links 19 11.3. References to Interface MIB Objects from MPLS MIB Modules 20 12. Management Options 21 13. Related IETF MIB Modules 22 13.1. pwe3 Working Group MIB Modules 22 13.2. ppvpn Working Group MIB Modules 22 13.2.1. PPVPN-MPLS-VPN-STD-MIB 22 13.3. ccamp Working Group MIB Modules 23 14. Traffic Engineering Working Group TE MIB 23 14.1. Choosing Between TE MIB Modules 23 Nadeau, Srinivasan and Farrel [Page 2] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 15. Security Considerations 24 16. Acknowledgements 25 17. Intellectual Property Consideration 25 18. Normative References 25 19. Informative References 26 20. Authors' Addresses 28 21. Full Copyright Statement 28 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 MIB modules. For additional information, this document also includes a brief note on MIB modules 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. The document begins with a brief outline of the SNMP framework. This is not intended to be a complete reference on SNMP, but is provided to give context to the rest of the document and to indicate reference material for readers that need to know more about SNMP. This document does not propose any additions to the MPLS MIB framework, nor define any standards for the Internet community. It is an informational document. In all cases, the reader is advised to turn to the document that defines the MIB module in question for further information. Comments should be made directly to the MPLS mailing list at mpls@uu.net. 2. Terminology This document uses terminology from the MPLS architecture document [RFC3031] and the following MPLS related MIB modules: MPLS TC MIB [TCMIB], MPLS LSR MIB [LSRMIB], MPLS TE MIB [TEMIB], MPLS LDP MIB [LDPMIB], MPLS FTN MIB [FTNMIB], TE LINK MIB [TELMIB], and PPVPN MPLS VPN MIB [VPNMIB]. Throughout this document hyphenated MIB names (such as MPLS- TE-STD-MIB) should be taken to refer to specific MIB modules. Non-hyphenated MIB names (such as MPLS LDP MIB) indicate MIB documents. Nadeau, Srinivasan and Farrel [Page 3] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 3. The SNMP 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]. 4. An Introduction to the MPLS Working Group MIB Modules This section addresses the MIB documents produced by the MPLS working group, namely MPLS TC MIB, MPLS LSR MIB, MPLS TE MIB, MPLS LDP MIB, MPLS FTN MIB, and TE LINK MIB. The rest of this section briefly describes the following: - the MPLS Object Identifier (OID) tree structure and the position of different MPLS related MIB modules on this tree; - the purpose of each of the MIB modules within the MIB documents, what it can be used for, and how it relates to the other MIB modules. Note that each MIB document contains one or more compliance statements for the modules and objects that it defines. The support for the different MIB modules and objects is, therefore beyond the scope of this document although some recommendations are included in the sections that follow. Nadeau, Srinivasan and Farrel [Page 4] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 4.1. Structure of the MPLS MIB OID Tree The MPLS MIB OID tree has the following structure. transmission -- RFC 2578 [RFC2578] | +- mplsStdMIB -- MPLS-TC-STD-MIB | | | +- mplsTCStdMIB -- MPLS-TC-STD-MIB | | | +- mplsLsrStdMIB -- MPLS-LSR-STD-MIB | | | +- mplsTeStdMIB -- MPLS-TE-STD-MIB | | | +- mplsLdpStdMIB -- MPLS-LDP-STD-MIB | | | +- mplsLdpAtmStdMIB -- MPLS-LDP-ATM-STD-MIB | | | +- mplsLdpFrameRelayStdMIB -- MPLS-LDP-FRAME-RELAY-STD-MIB | | | +- mplsLdpGenericStdMIB -- MPLS-LDP-GENERIC-STD-MIB | | | +- mplsFTNStdMIB -- MPLS-FTN-STD-MIB | +- teLinkStdMIB -- TE-LINK-STD-MIB Note: The OIDs for MIB modules are assigned and managed by IANA. They can be found in the referenced MIB documents. 4.2. MPLS-TC-STD-MIB MPLS-TC-STD-MIB defines textual conventions [RFC2579] that may be common to MPLS related MIB modules. These conventions allow multiple MIB modules to use the same syntax and format for a concept that is shared between the MIB modules. For example, labels are a central part of MPLS and need to be presented in many of the MIB modules. The textual convention for representing an MPLS label is defined in MPLS-TC-STD-MIB. All of the other MPLS MIB modules import textual convetions from this MIB module. 4.3. MPLS-LSR-STD-MIB MPLS-LSR-STD-MIB describes managed objects for modeling a MPLS Label Switching Router (LSR). This puts it at the heart of the management architecture for MPLS. This MIB module is used to model and manage the basic label switching behavior of an MPLS LSR. It represents the label forwarding information base (LFIB) of the LSR and provides a view of the LSPs that are being switched by the LSR in question. Nadeau, Srinivasan and Farrel [Page 5] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 Since basic MPLS label switching is common to all MPLS applications, this MIB module is referenced by many of the other MPLS MIB modules. In general, MPLS-LSR-STD-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 MPLS-LSR-STD-MIB and are typically referenced by other MIB modules in order to refer to the underlying MPLS LSP. For example, MPLS-TE-STD-MIB models traffic engineered tunnels. These tunnels map to one or more underlying MPLS LSPs. MPLS-TE-STD-MIB refers to the underlying LSP by pointing to cross-connect entries in MPLS-LSR-STD-MIB. 4.4. MPLS-LDP-STD-MIB MPLS-LDP-STD-MIB describes managed objects used to model and manage the MPLS Label Distribution Protocol (LDP) [RFC3036]. LDP is one of the MPLS protocols used to distribute labels and establish LSPs. This MIB module contains objects common to all LDP implementations. For an LDP implementation, that provides standard MIB support, this MIB module provides the core set of objects that are needed along with one or more of the other LDP MIB modules from the following sections. 4.5. MPLS-LDP-GENERIC-STD-MIB This MIB module provides objects for managing the LDP Per Platform Label Space and is typically implemented along with the MPLS-LDP-STD-MIB module. This MIB Module contains tables for configuring MPLS Generic Label Ranges. Although the LDP Specification does not provide a way for configuring Label Ranges for Generic Labels, the MIB module does provide a way to reserve a range of generic labels because this was thought to be useful by the working group. 4.6. MPLS-LDP-ATM-STD-MIB This MIB module is typically supported along with the MPLS-LDP-STD-MIB by LDP implementations if LDP uses ATM as the Layer 2 medium. Tables in this MIB module allow for configuring LDP to use ATM. Nadeau, Srinivasan and Farrel [Page 6] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 4.7. MPLS-LDP-FRAME-RELAY-STD-MIB This MIB module is typically supported along with the MPLS-LDP-STD-MIB by LDP implementations if LDP uses Frame Relay as the Layer 2 medium. Tables in this MIB module allow for configuration of LDP to use Frame Relay. 4.8. MPLS-TE-STD-MIB MPLS-TE-STD-MIB describes managed objects that are used to model and manage MPLS Traffic Engineered (TE) Tunnels. This MIB module is based around a table that represents TE tunnels that either originate from, traverse via or terminate on the LSR in question or. The MIB module provides configuration and statistics objects needed for TE tunnels. 4.9. MPLS-FTN-STD-MIB MPLS-FTN-STD-MIB describes managed objects that are used to model and manage the MPLS FEC-to-NHLFE (FTN) mappings that take place at an ingress Label Edge Router (LER). A LER is an LSR placed at the edge of an MPLS domain and passes traffic into and out of the MPLS domain. An ingress LER is responsible for classifying data and assigning it to a suitable LSP. This classification is done using Forwarding Equivalency Classes (FECs) that define the common attributes of data (usually packets) that will be treated in the same way. Once data has been classified it can be handed off to an LSP through the Next Hop Label Forwarding Entry (NHLFE). In the case of an IP-to-MPLS mapping, the FEC objects describe IP 6-tuples representing source and destination address ranges, source and destination port ranges, IPv4 Protocol field or IPv6 next-header field and the DiffServ Code Point (DSCP). 4.10. TE-LINK-STD-MIB TE-LINK-STD-MIB describes managed objects that are used to model and manage TE links, including bundled links, in an MPLS network. The TE link feature is designed to aggregate one or more similar data channels or TE links between a pair of LSRs. A TE link and is a sub-interface capable of carrying traffic engineered MPLS traffic. A bundled link is a sub-interface that bonds the traffic of a group of one or more TE links." Nadeau, Srinivasan and Farrel [Page 7] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 4.11. MIB Module Interdependencies This section provides an overview of the relationship between the MPLS MIB modules described above. More details of these relationships are given below once the MIB modules have been discussed in more detail. The arrows in the following diagram show a 'depends on' relationship. A "MIB module A depends on MIB module B" relationship means that MIB module A uses a structure or textual convention defined in MIB module B, or that MIB module A contains a pointer (index or RowPointer) to an object in MIB module B. +-------> MPLS-TC-STD-MIB | ^ | | | MPLS-LSR-STD-MIB <-----------------+ | | +<------- MPLS-LDP-STD-MIB ----------------->+ | ^ | | | | | +<-- MPLS-LDP-GENERIC-STD-MIB | | | | | +<-- MPLS-LDP-ATM-STD-MIB | | | | | +<-- MPLS-LDP-FRAME-RELAY-STD-MIB | | | +<------- MPLS-TE-STD-MIB ------------------>+ | ^ | | | | +<------- MPLS-FTN-STD-MIB ----------------->+ Thus: - All the MPLS MIB modules depend on MPLS-TC-STD-MIB. - MPLS-LDP-STD-MIB, MPLS-TE-STD-MIB and MPLS-FTN-STD-MIB contain references to objects in MPLS-LSR-STD-MIB. - MPLS-LDP-GENERIC-STD-MIB, MPLS-LDP-ATM-STD-MIB and MPLS-LDP- FRAME-RELAY-STD-MIB contain references to objects in MPLS- LDP-STD-MIB. - MPLS-FTN-STD-MIB contains references to objects in MPLS-TE- STD-MIB. 4.12. Dependencies on External MIB Modules With the exception of MPLS-TC-STD-MIB, all the MPLS MIB modules have dependencies on the Interfaces MIB [RFC2863]. MPLS-FTN-STD-MIB references IP-capable interfaces on which received traffic is to be classified using indexes in the Interface Table (ifTable) of this MIB module. The other MPLS MIB modules reference MPLS- capable interfaces in ifTable. Nadeau, Srinivasan and Farrel [Page 8] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 The Interfaces Group of the IF-MIB [RFC2863] defines generic managed objects for managing interfaces. The MPLS MIB modules contain media-specific extensions to the Interfaces Group for managing MPLS interfaces. The MPLS MIB modules assume the interpretation of the Interfaces Group to be in accordance with [RFC2863] which states that ifTable contains information on the managed resource's interfaces and that each sub-layer below the internetwork layer of a network interface is considered an interface. Thus, the MPLS interface is represented as an entry in ifTable. The inter-relation of entries in ifTable is defined by the Interfaces Stack Group defined in [RFC2863]. 5. Tables, Scalars and Notifications in MPLS-LSR-STD-MIB 5.1. Tables MPLS-LSR-STD-MIB contains the following tables. - The interface configuration table (mplsInterfaceConfTable) is used for enabling MPLS on MPLS-capable interfaces. - The in-segment (mplsInSegmentTable) and out-segment (mplsOutSegmentTable) tables are used to configure and monitor LSP segments carrying data into and out of the LSR, respectively. - The cross-connect table (mplsXCTable) is used to associate in and out segments in order to form a cross- connect (i.e. to represent an LSP transiting the LSR). - The label stack table (mplsLabelStackTable) allows the specification of multi-label stacks to be imposed on a given LSP at this LSR - The Traffic Parameter table (mplsTrafficParamTable) is used to specify and record LSP related traffic parameters. - The MPLS in-segment (mplsInSegmentPerfTable) and out- segment (mplsOutSegmentPerfTable) performance tables contain objects to measure the performance of LSPs. - The MPLS interface performance table (mplsInterfacePerfTable) has objects to measure MPLS performance on a per-interface basis. Nadeau, Srinivasan and Farrel [Page 9] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 5.2. Scalars Where tables in the MIB module have arbitrary indexes, scalars are provided to supply the next available index. This applies to mplsOutSegmentTable, mplsXCTable, mplsLabelStackTable and mplsTrafficParamTable. mplsMaxLabelStackDepth defines the maximum size of a imposed label stack supported at this LSR. mplsXCTrapEnable is used to enable and disable notifications from MPLS-LSR-STD-MIB. 5.3. Notifications MPLS-LSR-STD-MIB can issue two notifications (if notifications are enabled). - mplsXCUp reports when a cross-connect becomes active. - mplsXCDown reports when a cross-connect becomes inactive. 5.4. Dependencies Between MIB Module Tables The tables in MPLS-LSR-STD-MIB are related as shown on the diagram below. The arrows indicate a reference from one table to another. mplsInterfacePerfTable ^ | mplsInterfaceConfTable ^ ^ | | +----+ +----+ | | | mplsTrafficParamTable | mplsLabelStackTable | ^ ^ | ^ | | | | | mplsInSegmentTable mplsOutSegmentTable | | | | | +----> mplsXCTable <----+ | V V mplsInSegmentPerfTable mplsOutSegmentPerfTable Nadeau, Srinivasan and Farrel [Page 10] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 6. Tables, Scalars and Notifications in the LDP MIB 6.1. MIB Modules The MIB document for LDP contains four MIB modules. This structure makes it easier for an implementation to select only those modules that are relevant to it. The MIB Modules are the MPLS-LDP-STD-MIB, the MPLS-LDP-GENERIC-STD-MIB, the MPLS- LDP-ATM-STD-MIB and the MPLS-LDP-FRAME-RELAY-STD-MIB. The MPLS-LDP-STD-MIB defines objects which are specific to LDP without any Layer 2 objects. The MPLS-LDP-GENERIC-STD-MIB defines Layer 2 Per Platform Label Space objects for use with the MPLS-LDP-STD-MIB and for use on Ehternet. The MPLS- LDP-ATM-STD-MIB defines Layer 2 Asynchronous Transfer Mode (ATM) objects for use with the MPLS-LDP-STD-MIB. The MPLS-LDP- FRAME-RELAY-STD-MIB defines Layer 2 FRAME-RELAY objects for use with the MPLS-LDP-STD-MIB. The MPLS-LDP-STD-MIB module provides the core support and is typically supported along with at least one of the Layer 2 MIB modules. 6.2. Tables The tables in the LDP MIB for configuring the LDP behavior of an LSR are as follows. - The LDP Entity Table (mplsLdpEntityTable) provides a way to configure the LSR for using LDP. There must be at least one LDP Entity for the LSR to support LDP. Each entry/row in this table represents a single LDP Entity. - Several tables exist to help configure LDP's use of labels. These are spread through the MIB modules described in the previous section. They are: mplsLdpEntityGenLRTable, mplsLdpEntityAtmParmsTable and mplsLdpEntityAtmLRTable, mplsLdpEntityFrameRelayParmsTable and mplsLdpEntityFrLRTable. They are used to configure generic, ATM and Frame Relay labels as their names suggest. - The LDP Peer Table (mplsLdpPeerTable) is a read-only table, that contains information about LDP Peers known to LDP Entities. - The LDP Hello Adjacencies Table (mplsLdpHelloAdjacencyTable) is a table of all adjacencies between all LDP Entities and all LDP Peers. Nadeau, Srinivasan and Farrel [Page 11] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 - Several tables exist to monitor and control LDP sessions. The LDP Session Table (mplsLdpSessionTable) represents sessions between an LDP Entity and a Peer. The mplsLdpAtmSesTable and mplsLdpFrameRelaySesTable contain session information specific to ATM. - The MPLS LDP Session Peer Address Table (mplsLdpSesPeerAddrTable) stores addresses learned after session initialization via Address Message advertisement. - The LDP FEC Table (mplsFecTable) represents FEC (Forwarding Equivalence Class) information that may be in use on one or more LSPs. The LDP LSP FEC Table (mplsLdpLspFecTable) shows the FECs associated with each LSP. - MPLS-LDP-STD-MIB has a mapping table (mplsLdpLspTable) which maps the LDP MIB's representation of LDP sessions to the underlying LSR MIB's representation of the LSPs created by these sessions by pointing to mplsInSegmentTable, mplsOutSegmentTable and mplsXCTable, respectively. - Statistics may be gathered through the LDP Entity Statistics Table (mplsLdpEntityStatsTable) and the LDP Session Statistics Table (mplsLdpSesStatsTable) 6.3. Scalars Where tables in the MIB modules have arbitrary indexes, scalars are provided to supply the next available index. This applies to the mplsLdpEntityTable and the mplsFecTable. Two scalars exist to configure the LSR. The LSR ID is set in mplsLdpLsrId, and the loop detection capabilities are reported in mplsLdpLsrLoopDetectionCapable 6.4. Notifications MPLS-LDP-STD-MIB defines four notifications that a device can issue. - mplsLdpInitSesThresholdExceeded is reported when the number of Session Initialization messages exceeds a configured threshold. - mplsLdpPVLMismatch is issued if the Path Vector Limit for a configured Entity and Peer do not match. - mplsLdpSessionUp and mplsLdpSessionDown report the transition of Session state. Nadeau, Srinivasan and Farrel [Page 12] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 No scalar object is provided to enable and disable notifications from MPLS-LDP-STD-MIB. Instead, the implementer is referred to [RFC3413]. 6.5. Dependencies Between MIB Module Tables The many tables in the four LDP MIB modules are related as shown on the diagram below. The arrows indicate a reference from one table to another. Note that in many cases the reference is through an augmentation of the referenced table. mplsLdpEntityGenLRTable ------------->+ mplsLdpEntityAtmParmsTable ---------->+ mplsLdpEntityAtmLRTable ------------->+ mplsLdpEntityFrameRelayParmsTable --->+ mplsLdpEntityFrLRTable -------------->+ mplsLdpEntityStatsTable ------------->+ | mplsLdpHelloAdjacencyTable | | | | mplsLdpEntityTable <--+ | ^ ^ V | | mplsLdpPeerTable <-+- mplsLdpSesPeerAddrTable ^ | | V mplsLdpSessionTable ^ ^ | | mplsLdpSesStatsTable ------+ +-- mplsLdpLspFecTable mplsLdpAtmSesTable --------+ | | | mplsLdpFrameRelaySesTable--+ | | V | | mplsFecTable | V +-- mplsLdpLspTable 7. Tables, Scalars and Notifications in MPLS-TE-STD-MIB 7.1. Tables MPLS-TE-STD-MIB contains the following tables. - The Tunnel table (mplsTunnelTable) is used to configure and report MPLS tunnels. Note that reporting of tunnels in this table at transit LSRs is optional. Entries in the mplsTunnelTable are indexed by four objects. The source and destination LSR Ids give context to the entry, and an index (mplsTunnelIndexIndex) identifies the tunnel itself. However, the fourth index (mplsTunnelInstance) may give rise to some confusion since its usage is not clearly explained. Nadeau, Srinivasan and Farrel [Page 13] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 The description says: "Uniquely identifies an instance of a tunnel. It is useful to identify multiple instances of tunnels for the purposes of backup and parallel tunnels." In the case of backup tunnels, multiple instances of the same tunnel may be defined, but only one is active at any time. Different instances may have different properties (such as explicit routes), and one instance may be set up to protect against failure of another. Parallel tunnels may be used to provide load sharing or protection. The mplsTunnelInstancePriority object is used to indicate the precedence of tunnels with the same LSR Ids and mplsTunnelIndexIndex value. The mplsTunnelPrimaryInstance object gives a quick reference back to the preferred instance of the tunnel. The mplsTunnelIndexIndex value is typically signaled as the Tunnel ID, and the mplsTunnelInstance as the LSP Id in protocols where both fields exist. In protocols where there is only one identifying index (usually known as the LSP Id), only the mplsTunnelIndexIndex is signaled. - The Resource table (mplsTunnelResourceTable) is used to configure resources to be requested on this tunnel. The CRLDP resource table (mplsTunnelCRLDPResTable) is used to request additional resource details that are specific to tunnels signaled using CR-LDP. - The routes requested, computed and actually used for a tunnel are found in the Tunnel Hop Table (mplsTunnelHopTable) Tunnel Computed Hop Table (mplsTunnelCHopTable) and Tunnel Actual Hop Table (mplsTunnelARHopTable). - Statistics about the performance of tunnels may be gathered through the Tunnel Performance Table (mplsTunnelPerfTable). 7.2. Scalars Where tables in the MIB module have arbitrary indexes, scalars are provided to supply the next available index. This applies to the mplsTunnelTable, the mplsTunnelResourceTable and the mplsTunnelHopTable. Two scalars exist to configure the support for MPLS tunnels on the LSR. mplsTunnelTEDistProto lists the signaling methods and protocols supported. mplsTunnelMaxHops defines the size of route that may be configured on the LSR. Two further scalars enhance the statistics on the LSR by counting the number of configured (mplsTunnelConfigured) and active (mplsTunnelActive) tunnels. Nadeau, Srinivasan and Farrel [Page 14] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 The scalar mplsTunnelTrapEnable is used to enable and disable notifications from MPLS-TE-STD-MIB. 7.3. Notifications MPLS-TE-STD-MIB defines four notifications that a device can issue. - mplsTunnelUp and mplsTunnelDown report the transition of Tunnel state. - Rerouting and re-optimization of Tunnels paths are reported by mplsTunnelRerouted and mplsTunnelReoptimized. 7.4. Dependencies Between MIB Module Tables The tables in MPLS-TE-STD-MIB are related as shown on the diagram below. The arrows indicate a reference from one table to another. mplsTunnelPerfTable | V mplsTunnelTable ^ ^ | | mplsTunnelResourceTable +---mplsTunnelHopTable ^ | | +---mplsTunnelCHopTable mplsTunnelCRLDPResTable | +---mplsTunnelARHopTable 8. Tables, Scalars and Notifications in MPLS-FTN-STD-MIB 8.1. Tables MPLS-FTN-STD-MIB contains the following tables. - The FEC to NHLFE Table (mplsFTNTable) defines the FEC to NHLFE rules to be applied to incoming packets, and the actions to be taken on matching packets. - The FEC to NHLFE Map Table (mplsFTNMapTable) provides the capability to activate FTN rules defined in the mplsFTNTable on specific interfaces in the system. - Performance statistics for FTN rules are found in the mplsFTNPerfTable. Nadeau, Srinivasan and Farrel [Page 15] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 8.2. Scalars This MIB module contains the scalars mplsFTNTableLastChanged and mplsFTNMapTableLastChanged to indicate the last time an object changed in mplsFTNTable and mplsFTNMapTable respectively. Another scalar, mplsFTNIndexNext, is used to supply the next valid index for creating new conceptual rows in mplsFTNTable. 8.3. Notifications There are no notifications in this MIB module. 8.4. Dependencies Between MIB Module Tables The tables in MPLS-FTN-STD-MIB are related as shown on the diagram below. The arrows indicate a reference from one table to another. mplsFTNTable ^ ^ | | mplsFTNMapTable mplsFTNPerfTable 9. Tables and Objects in TE-LINK-STD-MIB 9.1. Tables TE-LINK-STD-MIB contains the following tables. - The TE link table (teLinkTable) is used to specify TE links, including bundled links, and their generic traffic engineering parameters. - The TE link descriptor table (teLinkDescriptorTable) is used to list the TE link descriptors. - The shared risk link group (SRLG) table (teLinkSrlgTable) is used to specify the SRLGs associated with TE links. - The TE link bandwidth table (teLinkBandwidthTable) is used to report priority-based bandwidth values associated with TE links. - The component link table (componentLinkTable) is used to identify the data- bearing component links that are associated with the TE links and specify the data-bearing link generic traffic engineering parameters. Nadeau, Srinivasan and Farrel [Page 16] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 - The component link descriptor table (componentLinkDescriptorTable) is used to list the data-bearing component link descriptors. - The component link bandwidth table (componentLinkBandwidthTable) is used to report priority-based bandwidth values associated with data- bearing component links. 9.2. Scalars There are no scalars in this MIB module. 9.3. Notifications There are no notifications in this MIB module. 9.4. Dependencies Between MIB Module Tables The tables in TE-LINK-STD-MIB are related as shown on the diagram below. The arrows indicate a reference from one table to another. Note that many of the associations between tables are through a common index that is the ifIndex of the related interface. teLinkTable ^ | teLinkDescriptorTable ---+ | teLinkSrlgTable ---------+ | teLinkBandwidthTable ----+ componentLinkTable ^ | componentLinkDescriptorTable ---+ | componentLinkBandwidthTable ----+ Nadeau, Srinivasan and Farrel [Page 17] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 10. Table Dependencies Between MPLS MIB Modules Section 4.11 gave an overview of how the MPLS MIB modules are related. Now that the tables in the MIB modules have been introduced, it is possible to give a more detailed diagram of these relationships. MPLS-TC-STD-MIB is left off the diagram since so many of the MIB module tables use textual conventions from that MIB module. mplsLsrXCTable mplsLsrInSegmentTable ^ ^ | | +---- mplsLdpLspTable | | mplsTunnelTable ------+ V ^ | mplsLsrOutSegmentTable | | mplsFTNTable ---------+ 11. A Note on Interfaces The Interfaces Group of the IF-MIB [RFC2863] defines generic managed objects for managing interfaces. The MPLS MIB modules make references to interfaces in order that it can be clearly determined where the procedures managed by the MIB modules should be performed. Additionally, the MPLS MIB modules (notably MPLS-TE-STD-MIB and TE-LINK-STD-MIB) utilize interface stacking within the Interface Group. 11.1. MPLS Tunnels as Interfaces The MPLS-TE-STD-MIB builds on the concept of managing MPLS Tunnels as logical interfaces. [RFC2863] states that the interfaces table (ifTable) contains information on the managed resource's interfaces, and that each sub-layer below the internetwork layer of a network interface is considered an interface. Thus, an MPLS Tunnel managed as an interface is represented as an entry in the ifTable. The interrelation of entries in the ifTable is defined by the Interfaces Stack Group defined in [RFC2863]. When using MPLS Tunnels as interfaces, the interface stack table might appear as follows: +------------------------------------------------+ | MPLS tunnel interface ifType = mplsTunnel(150) | +------------------------------------------------+ | MPLS interface ifType = mpls(166) | +------------------------------------------------+ | Underlying layer | +------------------------------------------------+ Nadeau, Srinivasan and Farrel [Page 18] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 In the diagram above, "Underlying layer" refers to the ifIndex of any interface type for which MPLS internetworking has been defined. Examples include ATM, Frame Relay, and Ethernet. A detailed listing of the mapping between ifTable objects and their use for MPLS Tunnels is given in [TEMIB]. A few key objects are listed here to provide an overview of the concepts. Each MPLS tunnel is represented by an entry in the ifTable. Each tunnel is therefore assigned a unique ifIndex. The type of an interface represented by an entry in the ifTable is indicated by the ifType object. The value that is allocated to identify an MPLS tunnel is 150. The ifOperStatus object reflects the actual operational status of MPLS tunnel and may be mapped from the mplsTunnelOperStatus object. It may be considered convenient and good management to set the ifName object to reflect the name of the MPLS tunnel as contained in the mplsTunnelName object. 11.2. Application of the Interfaces Group to TE Links The TE-LINK-STD-MIB also uses interface stacking to manage TE Link interfaces as logical interfaces. The TE Link interface is represented as an entry in the ifTable. The inter-relation of entries in the ifTable is defined by Interfaces Stack Group defined in [RFC2863]. When using TE Link interfaces, the interface stack table might appear as follows: +-------------------------------------------------------------------+ | MPLS interface ifType = mpls(166) | | ifIndex = 1 | +-------------------------------------------------------------------+ | TE link (bundled link) ifType = teLink(200) | | ifIndex = 2 | +--------------------------------+-+--------------------------------+ | TE link ifType = teLink(200) | | TE link ifType = teLink(200) | | ifIndex = 3 | | ifIndex = 4 | +--------------------------------+ +--------------------------------+ | Component link | | Component link | | ifType = opticalTransport(196) | | ifType = opticalTransport(196) | | ifIndex = 5 | | ifIndex = 6 | +--------------------------------+ +--------------------------------+ In the above diagram, "opticalTransport" is an example of an underlying physical interface: in this case an optical transport interface. TE link management and bundling can be seen in the levels of interface stacking. Two TE links are defined each managing an optical transport link. These two TE links are combined into a bundle which is managed as a single TE link interface. This TE Link interface supports MPLS and is presented as an MPLS interface. Nadeau, Srinivasan and Farrel [Page 19] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 A detailed listing of the mapping between ifTable objects and their use for TE Links is given in [TELMIB]. A few key objects are listed here to provide an overview of the concepts. Each TE Link interface is represented by a separate entry in the ifTable with a unique ifIndex. The type of an interface represented by an entry in the ifTable is indicated by the ifType object. The value that is allocated to identify a TE Link 200. 11.3. References to Interface MIB Objects from MPLS MIB Modules The MPLS-TE-STD-MIB contains two objects that reference the management of an MPLS tunnel as an interface. mplsTunnelIsIf is a TRuthValue that indicates whether the tunnel is present in the ifTable. If the tunnel is managed as an interface, the mplsTunnelIfIndex object contains the ifIndex that identifies the corresponding entry in the ifTable. The MPLS-LSR-STD-MIB includes a table (mplsInterfaceConfTable) for configuring the support for MPLS on specific interfaces. A conceptual row in this table is created automatically by an LSR for every interface that is capable of and configured for support of MPLS. A conceptual row in this table will exist if and only if a corresponding entry in ifTable exists with ifType = mpls(166). The fate of the entries in the two tables are closely linked so that if the entry in the ifTable is operationally disabled, the entry in the mplsInterfaceConfTable is deleted. During the life of an entry in the mplsInterfaceConfTable a corresponding entry is managed in the mplsInterfacePerfTable to show performance counters for the MPLS-capable interface. The ifIndex that identifies MPLS-capable interfaces also plays an important indexing role in the MPLS-LSR-STD-MIB. In- segments (that is incoming LSP labels) are represented in the mplsInSegmentTable which is indexed by the mplsInSegmentIfIndex and mplsInSegmentLabel objects. mplsInSegmentIfIndex is set to the ifIndex of the incoming MPLS-capable interface. mplsInSegmentLabel identifies the incoming MPLS label. Note that the corresponding mplsOutSegmentTable contains an mplsOutSegmentIfIndex object to identify the outgoing MPLS-capable interface, but that this does not form part of the index of the table. The MPLS-LDP-STD-MIB use ifIndex extensively to identify the interface over which MPLS is active. Within the MPLS-FTN-STD-MIB, the mplsFTNMapTable maps entries in the mplsFTNTable to interfaces on which the mplsFTNTable entries should be used. Interfaces are identified using their ifIndex values. Nadeau, Srinivasan and Farrel [Page 20] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 12. Management Options It is not the intention of this document to provide instructions or advice to implementers of Management Stations, Management Agents or managed entities. It is, however, useful to make some observations about how the MIB modules described above might be used to manage MPLS systems. All MPLS LSPs may appear in the MPLS-LSR-STD-MIB. At transit nodes they are seen as full cross-connects between incoming labels on incoming interfaces and outgoing labels on outgoing interfaces. At ingress or egress points the cross- connections are unbalanced having spoof upstream or downstream legs respectively. Split and merge points of LSPs may be represented as more complex cross-connects in the MPLS-LSR-STD-MIB. Similarly, bidirectional LSPs can be represented by using the same cross-connect index for each of the forward and reverse cross-connections. The modules in the LDP MIB are intended solely for use with LDP and CR-LDP. LSPs that are signaled through other means may conveniently be stored in the mplsLdpLspTable for consistency with LSPs set up using LDP, but there is little further value to this since the table gives only pointers into the MPLS-LSR-STD-MIB. If, however, the LSPs are established with associated FECs using some signaling method other than LDP (for example, BGP) it may be advantageous to use the mplsLdpLspTable, mplsFecTable and mplsLdpLspFecTable to correlate the LSPs. Note that if CR-LDP is the signaling protocol there is no requirement to use the LSP-related tables in the LDP MIB since the LSP will be adequately represented in the MPLS-TE- MIB and the MPLS-LSR-STD-MIB. MPLS tunnels may be represented in the MPLS-TE-STD-MIB with their cross-connects indicated in the MPLS-LSR-STD-MIB. Tunnels are often (although not always) set up with a series of constraints that may be represented in the MPLS- TE-STD-MIB. Note that a distinguishing feature of a tunnel is that it has an ingress and an egress, where LSPs established through LDP may be end-to-end or may be hop-by- hop. All LSPs (tunnels and non-tunnels) may be established as a result of signaling protocols already defined or for future study. In addition, LSPs may be manually set up by issuing configuration commands to each of the LSRs on the LSP. These commands may utilize SNMP by performing SET operations to the MIB module tables and objects described here. Alternatively, configuration may be through some non- standard interface such as a Command Line or a Graphical User Interface. Such configured LSPs may also be represented in the MIB module tables. Nadeau, Srinivasan and Farrel [Page 21] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 Do not be mislead by considerations of the "permanence" of LSPs when deciding which tables of which MIB modules to use. An MPLS tunnel may have a very long life expectancy if set up by an amnesiac user, or a very short lifetime is automatically provisioned to satisfy on-demand traffic requirements. Similarly, an LSP established in response to a routing protocol (sometimes known as a hop-by-hop LSP) may be equally stable or unstable. 13. Related IETF MIB Modules This section describes the broad interactions between MIB modules produced by the pwe3, ppvpn, and ccamp working groups and the MPLS MIB modules. This information is provided as background information and is not central to this document. 13.1. pwe3 Working Group MIB Modules The pwe3 working group has produced a document [PWE3FW] that includes a description of the framework for MIB modules within PWE3 operation. Since the PWE3 architecture includes the use of MPLS as an emulated service and as a PSN service, the MPLS MIB modules described above may be leveraged. The pwe3 framework document describes the interactions between the MPLS MIB modules and the PWE3 MIB modules. 13.2. ppvpn Working Group MIB Modules At present, the ppvpn working group has not included a discussion of how the MPLS MIB modules interact with the MIB modules being produced by that working group. The authors of this document hope to make a forthcoming addition to the ppvpn framework document [PPVPNFW] detailing these interactions. At the moment, there are two MIB modules [VPNMIB] and [VPNTCMIB] which are discussed next. 13.2.1. PPVPN-MPLS-VPN-STD-MIB PPVPN-MPLS-VPN-STD-MIB describes managed objects that are used to model and manage RFC2547bis MPLS VPNs [RFC2547Bis]. This MIB module contains tables which model virtual routing forwarding entries (VRFs), as well as the interfaces associated with those VRFs. 13.2.1.1. Position in the OID Tree transmission -- RFC 2578 [RFC2578] | +- vpnMIB -- PPVPN-MPLS-VPN-STD-MIB Nadeau, Srinivasan and Farrel [Page 22] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 13.2.1.2. Dependencies This MIB module currently has no direct dependencies to any of the MPLS MIB modules. This MIB module models MPLS VPN interfaces as entries in the Interfaces MIB's Interfaces Table (ifTable). This MIB module may be modified in the future to import textual conventions from MPLS-TC-STD-MIB. A specific textual conventions MIB module [VPNTCMIB] defines textual conventions that are imported into PPVPN-MPLS-VPN-STD-MIB. 13.3. ccamp Working Group MIB Modules The ccamp working group is developing MIB modules in support of GMPLS that interact directly with the MPLS MIB modules. Along with any MIB modules produced by the ccamp working group, a separate ccamp-specific Management Framework document is expected to be issued describing the relationship between these MIB modules and the existing MPLS (and other) MIB modules. 14. Traffic Engineering Working Group TE MIB The tewg has produced a traffic engineering MIB (the TE-MIB) [TEWGMIB] containing objects for monitoring traffic engineered at their ingress points. In many senses the TE-MIB contains the same information as MPLS-TE-STD-MIB. Both MIB modules can be used to monitor MPLS tunnels; however, the TE-MIB is minimalistic and caters best to TE tunnels as tunnels, at the expense of not having many advanced features of the MPLS-TE-STD-MIB, whereas the MPLS-TE-STD-MIB can deconstruct tunnels into hop-by-hop cross-connects, at the expense of more complexity. The TE-MIB module imports textual conventions from the MPLS-TC- STD-MIB module and so is dependent on that document. 14.1. Choosing Between TE MIB Modules The TE-MIB is a flexible MIB module designed to manage traffic engineering tunnels regardless of the implementation technology. This flexibility and a focus on simplicity leads to some compromises. - Some MPLS configuration parameters are left out. For example, the resource management in TE-MIB is confined to bandwidth, so missing the full IntServ control. - Other TE-MIB parameters are present but with only limited options. For example, the ability to configure different label distribution methods per LSP. Nadeau, Srinivasan and Farrel [Page 23] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 - Some of the objects in the TE-MIB are encoded as octet strings. Type discrimination is provided by a separate object and it is left to the Management System to decode the octet string for display purposes according to the display hint, and encode the string in the same way for SET operations. This is in contrast to the MPLS MIB modules which have individual objects with explicit encodings. Extensibility of the TE-MIB to related concepts such as DiffServ and Fast Reroute, and integrations with other MIB modules such as that in the MPLS-LSR-STD-MIB is not a work item at the time of writing. The MPLS MIB modules are more closely integrated as described in this document. Write/create access to the TE-MIB is only available at the ingress, where it can be used to configure an ingress to signal a tunnel with constraints. It cannot be used to configure hop-by-hop cross-connects to build a tunnel. 15. Security Considerations This document describes the inter-relationships amongst the different MIB modules relevant to MPLS management and as such does not have any security implications in and of itself. Each specific MIB document specifies specific MIB objects and such a document must provide a proper security considerations section that explains the security aspects of those objects. The attention of readers is particulalry drawn to the security implications of making MIB objects available for create or write access through an access protocol such as SNMP. SNMPv1 by itself is such an insecure environment. Even if the network itself is secure (for example by using IPSec), there is no control over who on the secure network is allowed to access and GET (read) the objects in this MIB. It is recommended that the implementors consider the security features as provided by the SNMPv3 framework. Specifically, the use of the User-based Security Model STD 62, RFC 3414 [RFC3414] and the View-based Access Control Model STD 62, RFC 3415 [RFC3415] is recommended. It is then a customer/user responsibility to ensure that the SNMP entity giving access to an instance of this MIB, is properly configured to give access to only those objects, and to those principals (users) that have legitimate rights to access them Nadeau, Srinivasan and Farrel [Page 24] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 16. Acknowledgements Many small pieces of text in this document have been borrowed from the documents that define the MIB modules described here. The authors would like to express appreciation to all who worked on those MIB documents. Thanks also to all those who attended the November 2002 MPLS MIB open meeting and gave constructive feedback, and in particular to Sharon Chisholm for her thoughts on Management Options. Thanks to Kireeti Kompella for revising the text on the TE-MIB. Without the consistent pressure and encouragement from Bert Wijnen, this document would not have been written. 17. Intellectual Property Consideration The IETF takes no position regarding the validity or scope of any intellectual property 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; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP-11. Copies of claims of rights made available for publication 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 implementors or users of this specification can be obtained from the IETF Secretariat. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to practice this standard. Please address the information to the IETF Executive Director. 18. Normative References [FTNMIB] Nadeau, T., Srinivasan, C., and A. Viswanathan, "Multiprotocol Label Switching (MPLS) FEC-To-NHLFE (FTN) Management Information Base", Internet Draft , April 2003 (work in progress). [LDPMIB] J. Cucchiara, et al., "Definitions of Managed Objects for the Multiprotocol Label Switching, Label Distribution Protocol (LDP)", , April 2003 (work in progress). Nadeau, Srinivasan and Farrel [Page 25] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 [LSRMIB] Srinivasan, C., Viswanathan, A. and T. Nadeau, "MPLS Label Switching Router Management Information Base", Internet Draft , October 2002 (work in progress). [RFC2863] McCloghrie, K. and F. Kastenholtz, "The Interfaces Group MIB ", RFC 2863, June 2000. [TCMIB] Nadeau, T., Cucchiara, J., (Editors) "Definitions of Textual Conventions for Multiprotocol Label Switching (MPLS) Management", Internet Draft , March 2003 (work in progress). [TELMIB] Dubuc, M., Dharanikota, S., Nadeau, T., J. Lang, "Traffic Engineering Management Information Base", Internet Draft , May 2003 (work in progress). [TEMIB] Srinivasan, C., Viswanathan, A. and T. Nadeau, "MPLS Traffic Engineering Management Information Base Using SMIv2", Internet Draft , November 2002 (work in progress). 19. Informative References [PPVPNFW] Callon, R., Suzuki, M., (Editors) "A Framework for Layer 3 Provider Provisioned Virtual Private Networks", Internet Draft , March 2003 (work in progress). [PWE3FW] Pate, P., (Editor), "Framework for Pseudo Wire Emulation Edge-to-Edge (PWE3)", Internet Draft , June, 2002 (work in progress). [RFC2026] S. Bradner, "The Internet Standards Process -- Revision 3", RFC 2026, October 1996. [RFC2401] Kent, S., and Atkinson, R., "Security Architecture for the Internet Protocol", RFC 2401, November 1998. [RFC2547Bis] Rosen, E. et al, "MPLS/BGP VPNs", Internet Draft , October 2002. [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. Nadeau, Srinivasan and Farrel [Page 26] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 [RFC2579] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M. and S. Waldbusser, "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999. [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 Callon, R., "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. [RFC3410] Case, J., Mundy, R., Partain, D. and Stewart, B., "Introduction and Applicability Statements for Internet-Standard Management Framework", RFC 3410, December 2002. [RFC3413] Levi, D., Meyer, P., Stewart, B., "Simple Network Management Protocol (SNMP) Applications", RFC 3413 December 2002. [RFC3414] Blumenthal, U., Wijnen, B., "User-based Security Model (USM) for version 3 of the Simple Network Management Protocol (SNMPv3)", RFC 3414, December 2002. [RFC3415] Wijnen, B., Presuhn, R., McCloghrie, K., "View- based Access Control Model (VACM) for the Simple Network Management Protocol (SNMP)", RFC 3415, December 2002. [TEWGMIB] Kompella, K., "A Traffic Engineering MIB", Internet Draft , September 2002 (work in progress). [VPNMIB] Nadeau, T., et al., "MPLS/BGP Virtual Private Network Management Information Base Using SMIv2", Internet Draft, , November 2002 (work in progress). [VPNTCMIB] Schliesser, B., Nadeau, T., "Definition of Textual Conventions for Provider Provisioned Virtual Private Network (PPVPN) Management", Internet Draft, , November 2002 (work in progress). Nadeau, Srinivasan and Farrel [Page 27] Internet Draft draft-ietf-mpls-mgmt-overview-06.txt June 2003 20. 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 Email: cheenu@alumni.princeton.edu Adrian Farrel Movaz Networks, Inc. 7926 Jones Branch Drive, Suite 615 McLean, VA 22102 Phone: +1-703-847-1867 Email: afarrel@movaz.com 21. Full Copyright Statement Copyright (C) The Internet Society (2003). 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 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. Nadeau, Srinivasan and Farrel [Page 28]