Network Working Group Thomas D. Nadeau
Internet Draft Cisco Systems, Inc.
Category: Informational
Expires: March 2004 Cheenu Srinivasan
Bloomberg L.P.
Adrian Farrel
Old Dog Consulting
September 2003
Multiprotocol Label Switching (MPLS) Management Overview
draft-ietf-mpls-mgmt-overview-09.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].
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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 document describes the management architecture for MPLS
and indicates the inter-relationships between the different
MIB modules used for MPLS network management.
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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. Indexing 10
5.4. Notifications 11
5.5. Dependencies Between MIB Module Tables 11
6. Tables, Scalars and Notifications in the LDP MIB 12
6.1. MIB Modules 12
6.2. Tables 12
6.3. Scalars 13
6.4. Notifications 14
6.5. Dependencies Between MIB Module Tables 14
7. Tables, Scalars and Notifications in MPLS-TE-STD-MIB 15
7.1. Tables 15
7.2. Scalars 16
7.3. Notifications 16
7.4. Dependencies Between MIB Module Tables 16
8. Tables, Scalars and Notifications in MPLS-FTN-STD-MIB 17
8.1. Tables 17
8.2. Scalars 17
8.3. Notifications 17
8.4. Dependencies Between MIB Module Tables 17
9. Tables and Objects in TE-LINK-STD-MIB 17
9.1. Tables 17
9.2. Scalars 18
9.3. Notifications 18
9.4. Dependencies Between MIB Module Tables 18
10. Table Dependencies Between MPLS MIB Modules 19
11. A Note on Interfaces 19
11.1. MPLS Tunnels as Interfaces 19
11.2. Application of the Interfaces Group to TE Links 20
11.3. References to Interface MIB Objects from MPLS MIB Modules 21
12. Management Options 22
13. Related IETF MIB Modules 23
13.1. PWE3 Working Group MIB Modules 23
13.2. PPVPN Working Group MIB Modules 23
13.2.1. PPVPN-MPLS-VPN-STD-MIB 23
13.3. CCAMP Working Group MIB Modules 24
14. Traffic Engineering Working Group TE MIB 24
14.1. Choosing Between TE MIB Modules 24
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15. Security Considerations 25
16. Acknowledgements 26
17. Intellectual Property Consideration 26
18. Normative References 26
19. Informative References 27
20. Authors' Addresses 29
21. Full Copyright Statement 29
1. Introduction
This document 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.
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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 document 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.
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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 conventions
from this MIB module.
4.3. MPLS-LSR-STD-MIB
MPLS-LSR-STD-MIB describes managed objects for modeling an 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.
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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 LSPs 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
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.
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4.7. MPLS-LDP-FRAME-RELAY-STD-MIB
This MIB module is typically supported along with
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. 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).
An 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 or tunnel.
This classification is done using Forwarding Equivalence
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 or tunnel 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
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.
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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 relationship "MIB module A depends on MIB module B" means that MIB
module A uses a an object, object identifier, 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.
Note that there is a textual convention (MplsIndexType) defined
in MPLS-LSR-STD-MIB that is imported by MPLS-LDP-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
IF-MIB [RFC2863]. The other MPLS MIB modules reference MPLS-
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capable interfaces in ifTable.
The Interfaces Group of 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].
Additionally, MPLS-LDP-ATM-STD-MIB imports the textual convention
AtmVpIdentifier from ATM-TC-MIB to represent an ATM virtual path
identifier, while MPLS-LDP-FRAME-RELAY-STD-MIB imports the textual
convention DLCI from FRAME-RELAY-DTE-MIB to represent a Data Link
Channel identifier.
MPLS-LDP-STD-MIB imports the textual conventions IndexInteger and
IndexIntegerNextFree from [RFC3289], and MPLS-TE-STD-MIB imports
IndexIntegerNextFree. IndexInteger provides a standard arbitrary
index while IndexIntegerNextFree is used by a management agent
that needs to select an appropriate value for an arbitrary index.
Finally, all of the MIB modules import standard textual conventions
such as integers, strings, timestamps etc. from the MIB modules in
which they are defined. This is business as usual for a MIB module
and is not discussed further in this document.
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 (mplsInterfaceTable)
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 in-segment mapping table (mplsInSegmentMapTable) provides a
look-up table that enables the discovery of an in-segment in
mplsInSegmentTable from the known incoming interface and incoming
label.
- 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).
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- The label stack table (mplsLabelStackTable) allows the
specification of multi-label stacks to be imposed on a
given LSP at this LSR
- 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.
5.2. Scalars
Where tables in the MIB module have arbitrary indexes, scalars are
provided to supply the next available index. This applies to
mplsInSegmentTable, mplsOutSegmentTable, mplsXCTable and
mplsLabelStackTable, but see the section on indexing, below.
mplsMaxLabelStackDepth defines the maximum size of a imposed label
stack supported at this LSR (and not, as the description in
MPLS-LSR-STD-MIB states, the maximum label stack depth supported by
the LSR).
mplsXCNotificationsEnable is used to enable and disable notifications
from MPLS-LSR-STD-MIB.
5.3. Indexing
Note that the indexing used by the tables in MPLS-LSR-STD-MIB is
unusual. A specific textual convention, MplsIndexType, is defined
in the MIB module and is used as the type for indexes to
mplsInSegmentTable, mplsOutSegmentTable, mplsXCTable and
mplsLabelStackTable. The textual convention is defined as an
octet string of between one and twenty four octets inclusive.
While this convention can be used to map simple integers and so
preserve the normal indexing techniques, it may also be used to
encode more complex indexing rules that may be useful to
implementations that subdivide their label spaces according to
physical or implementation constraints (such as placing the
responsibility for a subset of labels with a line card).
Note that it would be unusual, but not impossible, to make
sophisticated use of these indexes in a write-access MIB since
it would be hard to determine the 'next' index value. Thus,
non-simple values are likely only to be used in read-only MIBs
where the indexes are generated as a result of signaling protocol
implementations or other configuration means. The formatting and
interpretation of non-simple indexes is out of the scope of the
MIB module definition and is expected to be part of the
manageability statement for a particular device. When the
formatting is not known by an agent, it should treat the index as
a plain octet string containing an integer of between one and twenty
four octets.
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As described in the previous section, scalars are provided to
allow agents to discover a suitable value to use as an index when
creating a new row in one of these tables. These scalars all use
a second textual convention, MplsIndexNextType, also defined within
MPLS-LSR-STD-MIB. This textual convention allows the 'null string',
that is a string of length one octet with value 0x00. The null string
is used to indicate that either write access is not supported or no
more indexes are currently available.
Note that the usage of the nextIndex scalars is such that at any time
a scalar supplies a value that is currently unused as an index to the
specific table. In order to avoid lacunae in the indexing of a table
under normal usage, implementations are recommended to only change
the value in an nextIndex scalar when the index is used (that is,
when a row is created) and not when the nextIndex scalar is read. In
a 'busy' table this may result in row creation attempts failing and
agents having to re-read the scalar before making a second row
creation attempt. The desire to avoid this issue is in opposition to
the desire to avoid lacunae.
5.4. 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.
5.5. 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.
Note that the various MIB tables contain two instances of pointers
to external tables that are not currently defined. Entries in an
external Traffic Parameters Table (external_Traffic_Table) are
pointed to using RowPointers from the mplsInSegmentTable
(mplsInSegmentTrafficParamPtr) and from the mplsOutSegmentTable
(mplsOutSegmentTrafficParamPtr) to allow representation of the
traffic parameters for the MPLS segment - alternatively, the
pointers may indicate an entry in the Tunnel Resource Table
(mplsTunnelResourceTable) in MPLS-TE-STD-MIB. Similarly, an
external label table may be used to store label values if, for
some reason they are not stored in place within the LSR MIB tables.
This might occur if extra per label space information needs to be
stored, and paves the way for GMPLS where labels cannot always be
stored in a 32 bit value. RowPointers are used from the
mplsInSegmentTable (mplsInSegmentLabelPtr), the mplsOutSegmentTable
(mplsOutSegmentTopLabelPtr), and from the mplsLabelStackTable
(mplsLabelStackLabelPtr).
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mplsInterfacePerfTable
^
|
V
mplsInterfaceTable
^ ^
mplsInSegmentMapTable | | mplsLabelStackTable
| | | ^ |
| +----+ +----+ | |
| | | | |
| | external_Traffic_Table | | |
| | ^ ^ | | |
V | | | | | |
mplsInSegmentTable mplsOutSegmentTable |
| ^ ^ ^ ^ | |
| | | | | | V
+------+ | +----> mplsXCTable <----+ | +--+
| V V |
| mplsInSegmentPerfTable mplsOutSegmentPerfTable |
| |
+--------------> external_Label_Table <-------------+
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 MPLS-LDP-STD-MIB, MPLS-LDP-GENERIC-STD-MIB, MPLS-LDP-
ATM-STD-MIB and MPLS-LDP-FRAME-RELAY-STD-MIB.
MPLS-LDP-STD-MIB defines objects which are specific to LDP
without any Layer 2 objects. MPLS-LDP-GENERIC-STD-MIB
defines Layer 2 Per Platform Label Space objects for use
with MPLS-LDP-STD-MIB and for use on Ethernet. MPLS-LDP-ATM-
STD-MIB defines Layer 2 Asynchronous Transfer Mode (ATM)
objects for use with MPLS-LDP-STD-MIB. MPLS-LDP-FRAME-RELAY-
STD-MIB defines Layer 2 FRAME-RELAY objects for use with
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.
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- 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.
- Several tables exist to monitor and control LDP sessions. The LDP
Session Table (mplsLdpSessionTable) represents sessions between an
LDP Entity and a Peer. 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 mplsLdpEntityTable and mplsFecTable.
Two scalars exist to configure the LSR. The LSR ID is set in
mplsLdpLsrId, and the loop detection capabilities are reported
in mplsLdpLsrLoopDetectionCapable
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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.
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
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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 mplsTunnelTable are indexed by four
objects. The source and destination LSR IDs give
context to the entry, and an index (mplsTunnelIndex)
identifies the tunnel itself. However, the fourth index
(mplsTunnelInstance) may give rise to some confusion since
its usage is not clearly explained.
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 mplsTunnelIndex value. The mplsTunnelPrimaryInstance
object gives a quick reference back to the preferred instance
of the tunnel.
The mplsTunnelIndex 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 mplsTunnelIndex 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).
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7.2. Scalars
Where tables in the MIB module have arbitrary indexes, scalars
are provided to supply the next available index. This applies
to mplsTunnelTable, mplsTunnelResourceTable and
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.
The scalar mplsTunnelNotificationMaxRate is used to control the rate
at which notifications are issued from MPLS-TE-STD-MIB. A rate of
zero means that notifications must not be issued. If notifications
would be generated faster than the configured rate an implementation
may choose to discard notifications or queue them for distribution
at a quieter time.
7.3. Notifications
MPLS-TE-STD-MIB defines four notifications that a device can
issue. The rate of dispatch of notifications is controlled as
described in the previous section.
- 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
| |
V |
mplsTunnelResourceTable +--> mplsTunnelHopTable
^ |
| +--> mplsTunnelCHopTable
V |
mplsTunnelCRLDPResTable +--> mplsTunnelARHopTable
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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 Mapping 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.
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.
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- 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.
- 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 ----+
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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 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
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 |
+------------------------------------------------+
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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
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.
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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
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.
MPLS-LSR-STD-MIB includes a table (mplsInterfaceTable)
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 mplsInterfaceTable is deleted. During the life
of an entry in mplsInterfaceTable a corresponding
entry is managed in mplsInterfacePerfTable to show
performance counters for the MPLS-capable interface.
The ifIndex that identifies MPLS-capable interfaces also
plays an important indexing role in MPLS-LSR-STD-MIB. In-
segments (that is incoming LSP labels) are represented in
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.
MPLS-LDP-STD-MIB use ifIndex extensively to identify the
interface over which MPLS is active.
Within MPLS-FTN-STD-MIB, mplsFTNMapTable maps entries
in mplsFTNTable to interfaces on which mplsFTNTable
entries should be activated. Interfaces are identified using
their ifIndex values.
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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 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 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 mplsLdpLspTable for
consistency with LSPs set up using LDP, but there is little
further value to this since the table gives only pointers
into 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 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 MPLS-TE-
MIB and MPLS-LSR-STD-MIB.
MPLS tunnels may be represented in MPLS-TE-STD-MIB with
their cross-connects indicated in MPLS-LSR-STD-MIB.
Tunnels are often (although not always) set up with a
series of constraints that may be represented in 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.
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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
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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 (TE-MIB)
[TEWGMIB] containing objects for monitoring traffic engineered
tunnels at their ingress points.
In many senses TE-MIB contains the same information as
MPLS-TE-STD-MIB. Both MIB modules can be used to monitor MPLS
tunnels; however, TE-MIB is minimalistic and caters best to
TE tunnels as tunnels, at the expense of not having many advanced
features of MPLS-TE-STD-MIB, whereas 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
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.
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Extensibility of TE-MIB to related concepts such as
DiffServ and Fast Reroute, and integrations with other MIB
modules such as that in 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 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.
The purpose of TE-MIB module is to allow a Management Agent to
configure tunnels, and to inspect and monitor all tunnels (however
created) at their ingress points. It does not provide information
about tunnels at any other point in the network (that is, at transit
or egress nodes). This module can be used, for example, to configure
the constraints of a tunnel, whereupon the ingress would compute the
tunnel path and signal it. The MIB module can then be used at the
ingress to monitor the tunnel's path(s), their status and the
tunnel's uptime and counters. This MIB module is not designed 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 particularly 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 implementers
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
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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 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
implementers 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) Forwarding
Equivalence Class To Next Hop Label Forwarding
Entry (FEC-To-NHLFE) Management Information Base",
Internet Draft <draft-ietf-mpls-ftn-mib-08.txt>,
August 2003 (work in progress).
[LDPMIB] J. Cucchiara, et al., "Definitions of
Managed Objects for the Multiprotocol Label
Switching, Label Distribution Protocol
(LDP)", <draft-ietf-mpls-ldp-mib-13.txt>,
August 2003 (work in progress).
Nadeau, Srinivasan and Farrel [Page 26]
Internet Draft draft-ietf-mpls-mgmt-overview-09.txt September 2003
[LSRMIB] Srinivasan, C., Viswanathan, A. and T. Nadeau,
"MPLS Label Switching Router Management Information
Base", Internet Draft <draft-ietf-mpls-lsr-mib-12.txt>,
August 2003 (work in progress).
[RFC2863] McCloghrie, K. and F. Kastenholtz, "The
Interfaces Group MIB ", RFC 2863, June 2000.
[RFC3289] Baker, F., Chan, K. and A. Smith, "Management
Information Base for the Differentiated Services
Architecture", RFC 3289, May 2002.
[TCMIB] Nadeau, T., Cucchiara, J., (Editors) "Definitions of
Textual Conventions for Multiprotocol Label Switching
(MPLS) Management", Internet Draft <draft-ietf-mpls-tc-
mib-09.txt>, August 2003 (work in progress).
[TELMIB] Dubuc, M., Dharanikota, S., Nadeau, T., J. Lang,
"Traffic Engineering Management Information Base",
Internet Draft <draft-ietf-mpls-telink-mib-03.txt>,
August 2003 (work in progress).
[TEMIB] Srinivasan, C., Viswanathan, A. and T.
Nadeau, "MPLS Traffic Engineering Management
Information Base Using SMIv2", Internet
Draft <draft-ietf-mpls-te-mib-12.txt>,
August 2003 (work in progress).
19. Informative References
[PPVPNFW] Callon, R., Suzuki, M., (Editors) "A Framework
for Layer 3 Provider Provisioned Virtual Private
Networks", Internet Draft <draft-ietf-ppvpn-
framework-08.txt>, March 2003 (work in progress).
[PWE3FW] Pate, P., (Editor), "Framework for Pseudo Wire
Emulation Edge-to-Edge (PWE3)", Internet Draft
<draft-ietf-pwe3-framework-01.txt>, 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 <draft-ietf-ppvpn-rfc2547bis-03.txt>,
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.
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Internet Draft draft-ietf-mpls-mgmt-overview-09.txt September 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 <draft-ietf-tewg-mib-03.txt>,
September 2002 (work in progress).
[VPNMIB] Nadeau, T., et al., "MPLS/BGP Virtual Private
Network Management Information Base Using SMIv2",
Internet Draft, <draft-ietf-ppvpn-mpls-vpn-mib-
05.txt>, November 2002 (work in progress).
[VPNTCMIB] Schliesser, B., Nadeau, T., "Definition of
Textual Conventions for Provider Provisioned
Virtual Private Network (PPVPN) Management",
Internet Draft, <draft-ietf-ppvpn-tc-mib-
02.txt>, November 2002 (work in progress).
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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
Bloomberg L.P.,
499 Park Avenue,
New York, NY 10022
Tel: (212) 893-3682
Email: cheenu@bloomberg.net
Adrian Farrel
Old Dog Consulting
Tel: +44 (0) 1978 860944
Email: adrian@olddog.co.uk
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
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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
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Standards process must be followed, or as required to
translate it into languages other than English.
The limited permissions granted above are perpetual and
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DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT
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HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
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Nadeau, Srinivasan and Farrel [Page 29]
