Network Working Group G. Bourdon Request for Comments: 4045 France Telecom Category: Experimental April 2005
Extensions to Support Efficient Carrying of Multicast Traffic in Layer-2 Tunneling Protocol (L2TP)
Status of This Memo
This memo defines an Experimental Protocol for the Internet community. It does not specify an Internet standard of any kind. Discussion and suggestions for improvement are requested. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2005).
Abstract
The Layer Two Tunneling Protocol (L2TP) provides a method for tunneling PPP packets. This document describes an extension to L2TP, to make efficient use of L2TP tunnels within the context of deploying multicast services whose data will have to be conveyed by these tunnels.
Table of Contents
1. Introduction.................................................. 2 1.1. Conventions Used in This Document....................... 3 1.2. Terminology............................................. 3 2. Motivation for a Session-Based Solution....................... 4 3. Control Connection Establishment.............................. 5 3.1. Negotiation Phase....................................... 5 3.2. Multicast Capability AVP (SCCRQ, SCCRP)................. 5 4. L2TP Multicast Session Establishment Decision................. 6 4.1. Multicast States in LNS................................. 6 4.2. Group State Determination............................... 8 4.3. Triggering.............................................. 9 4.4. Multicast Traffic Sent from Group Members............... 10 5. L2TP Multicast Session Opening Process........................ 11 5.1. Multicast-Session-Request (MSRQ)........................ 11 5.2. Multicast-Session-Response (MSRP)....................... 12 5.3. Multicast-Session-Establishment (MSE)................... 12 6. Session Maintenance and Management............................ 13 6.1. Multicast-Session-Information (MSI)..................... 13 6.2. Outgoing Sessions List Updates.......................... 14 6.2.1. New Outgoing Sessions AVP (MSI)................. 15 6.2.2. New Outgoing Sessions Acknowledgement AVP (MSI). 15 6.2.3. Withdraw Outgoing Sessions AVP (MSI)............ 17 6.3. Multicast Packets Priority AVP (MSI).................... 17 6.3.1. Global Configuration............................ 18