Provisioning, Auto-Discovery, and Signaling in Layer 2 Virtual Private Networks (L2VPNs)
RFC 6074

Approval announcement
Draft of message to be sent after approval:

From: The IESG <iesg-secretary@ietf.org>
To: IETF-Announce <ietf-announce@ietf.org>
Cc: Internet Architecture Board <iab@iab.org>,
    RFC Editor <rfc-editor@rfc-editor.org>, 
    l2vpn mailing list <l2vpn@ietf.org>, 
    l2vpn chair <l2vpn-chairs@tools.ietf.org>
Subject: Protocol Action: 'Provisioning, Autodiscovery, and 
         Signaling in L2VPNs' to Proposed Standard 

The IESG has approved the following document:

- 'Provisioning, Autodiscovery, and Signaling in L2VPNs '
   <draft-ietf-l2vpn-signaling-08.txt> as a Proposed Standard

This document is the product of the Layer 2 Virtual Private Networks 
Working Group. 

The IESG contact persons are Mark Townsley and Jari Arkko.

A URL of this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-ietf-l2vpn-signaling-08.txt

Technical Summary

There are a number of different kinds of "Provider Provisioned Layer
2 VPNs" (L2VPNs).  The different kinds of L2VPN may have different
"provisioning models", i.e., different models for what information
needs to be configured in what entities.  Once configured, the
provisioning information is distributed by a "discovery process".
When the discovery process is complete, a signaling protocol is
automatically invoked.  The signaling protocol sets up the mesh of
Pseudowires (PWs) that form the (virtual) backbone of the L2VPN.  Any
PW signaling protocol needs to have a method which allows each PW
endpoint to identify the other; thus a PW signaling protocol will
have the notion of an endpoint identifier.  The semantics of the
endpoint identifiers which the signaling protocol uses for a
particular type of L2VPN are determined by the provisioning model.
This document specifies a number of L2VPN provisioning models, and
further specifies the semantic structure of the endpoint identifiers
required by each provisioning model.  It discusses the way in which
the endpoint identifiers are distributed by the discovery process,
especially when the discovery process is based upon the Border
Gateway Protocol (BGP).  It then specifies how the endpoint
identifiers are carried in the two signaling protocols that are used
to set up PWs, the Label Distribution Protocol (LDP) and the Layer 2
Tunneling Protocol (L2TPv3).


Working Group Summary

After WG Last Call, Luca Martini had raised an issue with
respect to whether or not there needed to be coordination of AII
Types between the l2vpn-signaling draft and the emergent MS-PW work.
Luca proposed a solution to this dilemma on the L2VPN WG list:
http://www.ietf.org/mail-archive/web/l2vpn/current/msg01121.html

A discussion ensued between Bruce, Luca, Chris Metz, Florin,
Mustapha, Vach & Shane to resolve it.  In summary, we have all agreed
that l2vpn-signaling is its own application and its use of Type-1
AII's is sufficient for it.  In fact, procedures developed in
l2vpn-signaling already account for PW routing/stitching & signaling
as it relates to D-VPLS, (with Type-1 AII's), but do not give one the
granularity of routing that MS-PW is aiming for.  Another key difference
is that l2vpn-signaling is focused on auto-discovery mechanisms for
groups of PW's (e.g.: L2VPN's), whereas MS-PW is focused on both
routing and signaling invidual PW's (not groups of PW's).  In fact,
it's not clear that MS-PW will initially be designed to support
routing+signaling of groups of PW's, (which is another thing that
distinguishes it from l2vpn-signaling).


Protocol Quality

The protocol is being implemented by at least two vendors.

RFC Editor Note:

Please add a normative reference for RFC 2119 and a citation to it at the end
of section 1.  

Please replace:

3.3.2.1.  BGP-based auto-discovery

   A framework for BGP-based auto-discovery for a generic L2VPN service
   is described in [I-D.ietf-l3vpn-bgpvpn-auto], section 3.2.  In this
   section we specify how BGP-based auto-discovery can be used to build
   VPWS instances.

With:

3.3.2.1.  BGP-based auto-discovery

 In this  section we specify how BGP can be used to discover the  information
necessary to build VPWS instances. 

And replace: 

    "A framework for BGP-based auto-discovery for a generic L2VPN service
    is described in [I-D.ietf-l3vpn-bgpvpn-auto], section 3.2.  In this
    section we specify how BGP-based auto-discovery can be used to build
    VPLS instances."

With:

    "In this section we specify how BGP can be used to discover the  
     information necessary to build a VPLS instance."


Also, please remove the bibliographic reference to [I-D.ietf-l3vpn-bgpvpn-auto]
in its entirety.