Intermediate System to Intermediate System (IS-IS) Extensions in Support of Generalized Multi-Protocol Label Switching (GMPLS) (RFC4205)
Original Publication Date: 2005-Oct-01
Included in the Prior Art Database: 2019-Feb-14
Internet Society Requests For Comment (RFCs)
K. Kompella: AUTHOR [+1]
This document specifies encoding of extensions to the IS-IS routing protocol in support of Generalized Multi-Protocol Label Switching (GMPLS). This memo provides information for the Internet community.
Network Working Group K. Kompella, Ed. Request for Comments: 4205 Y. Rekhter, Ed. Updates: 3784 Juniper Networks Category: Informational October 2005
Intermediate System to Intermediate System (IS-IS) Extensions in Support of Generalized Multi-Protocol Label Switching (GMPLS)
Status of This Memo
This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited.
Copyright (C) The Internet Society (2005).
This document specifies encoding of extensions to the IS-IS routing protocol in support of Generalized Multi-Protocol Label Switching (GMPLS).
This document specifies extensions to the IS-IS routing protocol in support of carrying link state information for Generalized Multi- Protocol Label Switching (GMPLS). The set of required enhancements to IS-IS are outlined in [GMPLS-ROUTING]. Support for unnumbered interfaces assumes support for the "Point-to-Point Three-Way Adjacency" IS-IS Option type [ISIS-3way].
In this section we define the enhancements to the Traffic Engineering (TE) properties of GMPLS TE links that can be announced in IS-IS Link State Protocol Data Units.
In this document, we enhance the sub-TLVs for the extended IS reachability TLV (see [ISIS-TE]) in support of GMPLS. Specifically, we add the following sub-TLVs:
Sub-TLV Type Length Name 4 8 Link Local/Remote Identifiers 20 2 Link Protection Type 21 variable Interface Switching Capability Descriptor
Kompella & Rekhter Informational [Page 1]
RFC 4205 IS-IS Extensions for MPLS October 2005
We further add one new TLV to the TE TLVs:
TLV Type Length Name 138 variable Shared Risk Link Group
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].
1.1. Link Local/Remote Identifiers
A Link Local Interface Identifiers is a sub-TLV of the extended IS reachability TLV. The type of this sub-TLV is 4, and length is eight octets. The value field of this sub-TLV contains four octets of Link Local Identifier followed by four octets of Link Remote Identifier (see Section "Support for unnumbered links" of [GMPLS-ROUTING]). If the Link Remote Identifier is unknown, it is set to 0.
The following illustrates encoding of the Value field of the Link Local/Remote Identifiers sub-TLV.
0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Link Local Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Link Remote Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Link Local/Remote Identifiers sub-TLV MUST NOT occur more than once within the extended IS reachability TLV. If the Link Local/Remote Identifiers sub-TLV occurs more than once within the extended IS reachability TLV, the receiver S...