2.5.8 Multiprotocol Label Switching (mpls)

NOTE: This charter is a snapshot of the 49th IETF Meeting in San Diego, California. It may now be out-of-date. Last Modified: 17-Nov-00


George Swallow <swallow@cisco.com>
Vijay Srinivasan <vijay@cosinecom.com>

Routing Area Director(s):

David Oran <oran@cisco.com>
Rob Coltun <rcoltun@redback.com>

Routing Area Advisor:

Rob Coltun <rcoltun@redback.com>

Mailing Lists:

General Discussion:mpls@uu.net
To Subscribe: mpls-request@uu.net
In Body: subscribe (unsubscribe)
Archive: http://cell.onecall.net/cell-relay/archives/mpls/mpls.index.html

Description of Working Group:

The MPLS working group has been responsible for standardizing a base technology for using label switching and for the implementation of label-switched paths over various link-level technologies, such as Packet-over-Sonet, Frame Relay, ATM, and LAN technologies (e.g. all forms of Ethernet, Token Ring, etc.). This includes procedures and protocols for the distribution of labels between routers, encapsulations and multicast considerations.

The initial goals of the working group have been largely completed. In particular, it has produced a number of RFCs (see list below) that define the base Label Distribution Protocol (LDP), the basic MPLS architecture and encapsulations, and definitions for how MPLS runs over ATM and Frame Relay links.

The current goals of the working group are:

1. Complete outstanding items from the original MPLS effort:


(6/12) Applicability Statement for Extensions to RSVP for LSP-Tunnels (8/08) Applicability Statement for CR-LDP (6/12) LDP State Machine


(10/19/99) MPLS Loop Prevention Mechanism

Standards Track:

(8/08) Constraint-Based LSP Setup using LDP (2/07) Carrying Label Information in BGP-4 (8/29) Extensions to RSVP for LSP Tunnels (8/29) MPLS Support of Differentiated Services (6/27) LSP Modification Using CR-LDP (9/01) Definitions of Managed Objects for LDP (8/29) MPLS Label Switch Router Management Information Base

2. Specify appropriate extensions to LDP and RSVP for authentication of LSP originators.

3. Document additional MPLS encapsulations to allow the operation of label-switched paths over additional lower-layer technologies, such as time-division (e.g. SONET ADMs), wavelength (optical lambdas) and spatial switching (e.g. incoming fiber to outgoing fiber).

Goals and Milestones:

Mar 97


Produce Framework Document Internet-Draft to contain goals with detailed motivations and description of solution space, possible approaches

May 97


Submit Framework Document to IESG (Informational RFC)*

May 97


Freeze Internet Draft for carrying label information over serial lines (p2p links) and over LAN media (e.g., Ethernet, Token Ring, FDDI)

Jun 97


Submit Achitecture Document to IESG (Informational RFC)

Aug 97


Submit specifications for the protocol to distribute label binding information for unicast routes to IESG (Standards Track)

Oct 97


Submit specifications for handling label binding information (including distribution of this information) for multicast routes to IESG (Standards Track)

Dec 97


Submit specifications for Operation over ATM to IESG (Standards Track)

Dec 97


Submit specifications for carrying label information over serial lines (p2p links) and over LAN media (e.g., Ethernet, Token Ring, FDDI) to IESG (Standards Track)

Apr 98


Submit procedures for Host Behavior to IESG (Standards Track)

Apr 98


AD review status of WG efforts and determine whether to close down or not. If not, identify next set of milestones.

Nov 00


Submit documents from original MPLS effort to IESG


Request For Comments:






Requirements for Traffic Engineering Over MPLS

Current Meeting Report

None received.


None received.