Request for Comments: 3811 Cisco Systems, Inc.
Category: Standards Track J. Cucchiara, Ed.
Marconi Communications, Inc.
June 2004
Definitions of Textual Conventions (TCs) for
Multiprotocol Label Switching (MPLS) Management
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2004).
Abstract
This memo defines a Management Information Base (MIB) module which
contains Textual Conventions to represent commonly used Multiprotocol
Label Switching (MPLS) management information. The intent is that
these TEXTUAL CONVENTIONS (TCs) will be imported and used in MPLS
related MIB modules that would otherwise define their own
representations.
Table of Contents
1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . 2
2. The Internet-Standard Management Framework. . . . . . . . . . 2
3. MPLS Textual Conventions MIB Definitions. . . . . . . . . . . 2
4. References. . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.1. Normative References. . . . . . . . . . . . . . . . . . 16
4.2. Informative References. . . . . . . . . . . . . . . . . 17
5. Security Considerations . . . . . . . . . . . . . . . . . . . 17
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
7. Contributors. . . . . . . . . . . . . . . . . . . . . . . . . 18
8 Acknowledgements. . . . . . . . . . . . . . . . . . . . . . . 19
9. Authors’ Addresses. . . . . . . . . . . . . . . . . . . . . . 19
10. Full Copyright Statement. . . . . . . . . . . . . . . . . . . 20
1. Introduction
This document defines a MIB module which contains Textual Conventions
for Multiprotocol Label Switching (MPLS) networks. These Textual
Conventions should be imported by MIB modules which manage MPLS
networks.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
For an introduction to the concepts of MPLS, see [RFC3031].
2. The Internet-Standard Management Framework
For a detailed overview of the documents that describe the current
Internet-Standard Management Framework, please refer to section 7 of
RFC 3410 [RFC3410].
Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. MIB objects are generally
accessed through the Simple Network Management Protocol (SNMP).
Objects in the MIB are defined using the mechanisms defined in the
Structure of Management Information (SMI). This memo specifies a MIB
module that is compliant to the SMIv2, which is described in STD 58,
RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580
[RFC2580].
3. MPLS Textual Conventions MIB Definitions
MPLS-TC-STD-MIB DEFINITIONS ::= BEGIN
IMPORTS
MODULE-IDENTITY,
Unsigned32, Integer32,
transmission FROM SNMPv2-SMI -- [RFC2578]
TEXTUAL-CONVENTION
FROM SNMPv2-TC; -- [RFC2579]
mplsTCStdMIB MODULE-IDENTITY
LAST-UPDATED "200406030000Z" -- June 3, 2004
ORGANIZATION
"IETF Multiprotocol Label Switching (MPLS) Working
Group."
CONTACT-INFO
" Thomas D. Nadeau
Cisco Systems, Inc.
tnadeau@cisco.com
Joan Cucchiara
Marconi Communications, Inc.
jcucchiara@mindspring.com
Cheenu Srinivasan
Bloomberg L.P.
cheenu@bloomberg.net
Arun Viswanathan
Force10 Networks, Inc.
arunv@force10networks.com
Hans Sjostrand
ipUnplugged
hans@ipunplugged.com
Kireeti Kompella
Juniper Networks
kireeti@juniper.net
Email comments to the MPLS WG Mailing List at
mpls@uu.net."
DESCRIPTION
"Copyright (C) The Internet Society (2004). The
initial version of this MIB module was published
in RFC 3811. For full legal notices see the RFC
itself or see:
http://www.ietf.org/copyrights/ianamib.html
This MIB module defines TEXTUAL-CONVENTIONs
for concepts used in Multiprotocol Label
Switching (MPLS) networks."
REVISION "200406030000Z" -- June 3, 2004
DESCRIPTION
"Initial version published as part of RFC 3811."
::= { mplsStdMIB 1 }
mplsStdMIB OBJECT IDENTIFIER
::= { transmission 166 }
MplsAtmVcIdentifier ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"A Label Switching Router (LSR) that
creates LDP sessions on ATM interfaces
uses the VCI or VPI/VCI field to hold the
LDP Label.
VCI values MUST NOT be in the 0-31 range.
The values 0 to 31 are reserved for other uses
by the ITU and ATM Forum. The value
of 32 can only be used for the Control VC,
although values greater than 32 could be
configured for the Control VC.
If a value from 0 to 31 is used for a VCI
the management entity controlling the LDP
subsystem should reject this with an
inconsistentValue error. Also, if
the value of 32 is used for a VC which is
NOT the Control VC, this should
result in an inconsistentValue error."
REFERENCE
"MPLS using LDP and ATM VC Switching, RFC3035."
SYNTAX Integer32 (32..65535)
MplsBitRate ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"If the value of this object is greater than zero,
then this represents the bandwidth of this MPLS
interface (or Label Switched Path) in units of
’1,000 bits per second’.
The value, when greater than zero, represents the
bandwidth of this MPLS interface (rounded to the
nearest 1,000) in units of 1,000 bits per second.
If the bandwidth of the MPLS interface is between
((n * 1000) - 500) and ((n * 1000) + 499), the value
of this object is n, such that n > 0.
If the value of this object is 0 (zero), this
means that the traffic over this MPLS interface is
considered to be best effort."
SYNTAX Unsigned32 (0|1..4294967295)
MplsBurstSize ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"The number of octets of MPLS data that the stream
may send back-to-back without concern for policing.
The value of zero indicates that an implementation
does not support Burst Size."
SYNTAX Unsigned32 (0..4294967295)
MplsExtendedTunnelId ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"A unique identifier for an MPLS Tunnel. This may
represent an IPv4 address of the ingress or egress
LSR for the tunnel. This value is derived from the
Extended Tunnel Id in RSVP or the Ingress Router ID
for CR-LDP."
REFERENCE
"RSVP-TE: Extensions to RSVP for LSP Tunnels,
[RFC3209].
Constraint-Based LSP Setup using LDP, [RFC3212]."
SYNTAX Unsigned32(0..4294967295)
MplsLabel ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"This value represents an MPLS label as defined in
[RFC3031], [RFC3032], [RFC3034], [RFC3035] and
[RFC3471].
The label contents are specific to the label being
represented, such as:
* The label carried in an MPLS shim header
(for LDP this is the Generic Label) is a 20-bit
number represented by 4 octets. Bits 0-19 contain
a label or a reserved label value. Bits 20-31
MUST be zero.
The following is quoted directly from [RFC3032].
There are several reserved label values:
i. A value of 0 represents the
’IPv4 Explicit NULL Label’. This label
value is only legal at the bottom of the
label stack. It indicates that the label
stack must be popped, and the forwarding
of the packet must then be based on the
IPv4 header.
ii. A value of 1 represents the
’Router Alert Label’. This label value is
legal anywhere in the label stack except at
the bottom. When a received packet
contains this label value at the top of
the label stack, it is delivered to a
local software module for processing.
The actual forwarding of the packet
is determined by the label beneath it
in the stack. However, if the packet is
forwarded further, the Router Alert Label
should be pushed back onto the label stack
before forwarding. The use of this label
is analogous to the use of the
’Router Alert Option’ in IP packets
[RFC2113]. Since this label
cannot occur at the bottom of the stack,
it is not associated with a
particular network layer protocol.
iii. A value of 2 represents the
’IPv6 Explicit NULL Label’. This label
value is only legal at the bottom of the
label stack. It indicates that the label
stack must be popped, and the forwarding
of the packet must then be based on the
IPv6 header.
iv. A value of 3 represents the
’Implicit NULL Label’.
This is a label that an LSR may assign and
distribute, but which never actually
appears in the encapsulation. When an
LSR would otherwise replace the label
at the top of the stack with a new label,
but the new label is ’Implicit NULL’,
the LSR will pop the stack instead of
doing the replacement. Although
this value may never appear in the
encapsulation, it needs to be specified in
the Label Distribution Protocol, so a value
is reserved.
v. Values 4-15 are reserved.
* The frame relay label can be either 10-bits or
23-bits depending on the DLCI field size and the
upper 22-bits or upper 9-bits must be zero,
respectively.
* For an ATM label the lower 16-bits represents the
VCI, the next 12-bits represents the VPI and the
remaining bits MUST be zero.
* The Generalized-MPLS (GMPLS) label contains a
value greater than 2^24-1 and used in GMPLS
as defined in [RFC3471]."
REFERENCE
"Multiprotocol Label Switching Architecture,
RFC3031.
MPLS Label Stack Encoding, [RFC3032].
Use of Label Switching on Frame Relay Networks,
RFC3034.
MPLS using LDP and ATM VC Switching, RFC3035.
Generalized Multiprotocol Label Switching
(GMPLS) Architecture, [RFC3471]."
SYNTAX Unsigned32 (0..4294967295)
MplsLabelDistributionMethod ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"The label distribution method which is also called
the label advertisement mode [RFC3036].
Each interface on an LSR is configured to operate
in either Downstream Unsolicited or Downstream
on Demand."
REFERENCE
"Multiprotocol Label Switching Architecture,
RFC3031.
LDP Specification, RFC3036, Section 2.6.3."
SYNTAX INTEGER {
downstreamOnDemand(1),
downstreamUnsolicited(2)
}
MplsLdpIdentifier ::= TEXTUAL-CONVENTION
DISPLAY-HINT "1d.1d.1d.1d:2d"
STATUS current
DESCRIPTION
"The LDP identifier is a six octet
quantity which is used to identify a
Label Switching Router (LSR) label space.
The first four octets identify the LSR and
must be a globally unique value, such as a
32-bit router ID assigned to the LSR, and the
last two octets identify a specific label
space within the LSR."
SYNTAX OCTET STRING (SIZE (6))
MplsLsrIdentifier ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"The Label Switching Router (LSR) identifier is the
first 4 bytes of the Label Distribution Protocol
(LDP) identifier."
SYNTAX OCTET STRING (SIZE (4))
MplsLdpLabelType ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"The Layer 2 label types which are defined for MPLS
LDP and/or CR-LDP are generic(1), atm(2), or
frameRelay(3)."
SYNTAX INTEGER {
generic(1),
atm(2),
frameRelay(3)
}
MplsLSPID ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"A unique identifier within an MPLS network that is
assigned to each LSP. This is assigned at the head
end of the LSP and can be used by all LSRs
to identify this LSP. This value is piggybacked by
the signaling protocol when this LSP is signaled
within the network. This identifier can then be
used at each LSR to identify which labels are
being swapped to other labels for this LSP. This
object can also be used to disambiguate LSPs that
share the same RSVP sessions between the same
source and destination.
For LSPs established using CR-LDP, the LSPID is
composed of the ingress LSR Router ID (or any of
its own IPv4 addresses) and a locally unique
CR-LSP ID to that LSR. The first two bytes carry
the CR-LSPID, and the remaining 4 bytes carry
the Router ID. The LSPID is useful in network
management, in CR-LSP repair, and in using
an already established CR-LSP as a hop in
an ER-TLV.
For LSPs signaled using RSVP-TE, the LSP ID is
defined as a 16-bit (2 byte) identifier used
in the SENDER_TEMPLATE and the FILTER_SPEC
that can be changed to allow a sender to
share resources with itself. The length of this
object should only be 2 or 6 bytes. If the length
of this octet string is 2 bytes, then it must
identify an RSVP-TE LSPID, or it is 6 bytes,
it must contain a CR-LDP LSPID."
REFERENCE
"RSVP-TE: Extensions to RSVP for LSP Tunnels,
[RFC3209].
Constraint-Based LSP Setup using LDP,
[RFC3212]."
SYNTAX OCTET STRING (SIZE (2|6))
MplsLspType ::= TEXTUAL-CONVENTION
STATUS current