Subject: [Idr] I-D Action: draft-ietf-idr-tunnel-encaps-01.txt

From: [email-masked]
Date: Mon, 21 Dec 2015 09:15:12 -0800

A New Internet-Draft is available from the on-line Internet-Drafts directories.
 This draft is a work item of the Inter-Domain Routing Working Group of the IETF.

        Title           : The BGP Tunnel Encapsulation Attribute
        Authors         : Eric C. Rosen
                          Keyur Patel
                          Gunter Van de Velde
	Filename        : draft-ietf-idr-tunnel-encaps-01.txt
	Pages           : 39
	Date            : 2015-12-21

Abstract:
   RFC 5512 defines a BGP Path Attribute known as the "Tunnel
   Encapsulation Attribute".  This attribute allows one to specify a set
   of tunnels.  For each such tunnel, the attribute can provide the
   information needed to create the tunnel and the corresponding
   encapsulation header.  The attribute can also provide information
   that aids in choosing whether a particular packet is to be sent
   through a particular tunnel.  RFC 5512 states that the attribute is
   only carried in BGP UPDATEs that have the "Encapsulation Subsequent
   Address Family (Encapsulation SAFI)".  This document deprecates the
   Encapsulation SAFI (which has never been used), and specifies
   semantics for the attribute when it is carried in UPDATEs of certain
   other SAFIs.  This document adds support for additional tunnel types,
   and allows a remote tunnel endpoint address to be specified for each
   tunnel.  This document also provides support for specifying fields of
   any inner or outer encapsulations that may be used by a particular
   tunnel.

   This document obsoletes RFC 5512.

The IETF datatracker status page for this draft is:
https://datatracker.ietf.org/doc/draft-ietf-idr-tunnel-encaps/

There's also a htmlized version available at:
https://tools.ietf.org/html/draft-ietf-idr-tunnel-encaps-01

A diff from the previous version is available at:
https://www.ietf.org/rfcdiff?url2=draft-ietf-idr-tunnel-encaps-01

Please note that it may take a couple of minutes from the time of submission
until the htmlized version and diff are available at tools.ietf.org.

Internet-Drafts are also available by anonymous FTP at:
ftp://ftp.ietf.org/internet-drafts/

---

From: Eric C Rosen <[email-masked]>
Date: Mon, 28 Dec 2015 10:20:34 -0500

The -01 revision of draft-ietf-idr-tunnel-encaps has the following 
changes from the -00 revision:

- By popular request, it has been written in such a way as to obsolete 
RFC5512.  This means that anything useful in RFC5512 had to be 
incorporated into the new draft.  I would welcome opinions on whether 
this was done correctly.

- Two new sub-TLVs are specified:  "MPLS Label Stack" and "Prefix-SID".  
I would welcome opinions on whether these are useful or not.  (I'm 
pretty sure that the first is useful, the second is more speculative.)

- If you are familiar with deployed uses of the Encapsulation Extended 
Community, the Color Extended Community, or the Router's MAC Extended 
Community, it may be worth checking section 4 to make sure that the 
draft does not introduce any problems.

- I wish more folks would take a critical look at section 8, which is 
primarily about the use of VXLAN/NVGRE/VXLAN-GPE together with labeled 
address families.

I would also be interested in hearing if anyone has an opinion on the 
utility of using this sort of mechanism to signal IPsec tunnels.  Once 
RFC 5512 is obsoleted, RFC 5566 ("BGP IPsec Tunnel Encapsulation 
Attribute") will need to be revised.  It might be possible to generalize 
that in such a way as to facilitate the secure interconnection of two 
private ASes across the public Internet.  Comments on whether RFC 5566 
takes a reasonable approach would be welcome.