RE: E2E VoIP over MPLS ('VoMPLS') Header Compression - End-to-End MPLS

> I remember reading some work done on Voice over MPLS directly 
> without using RTP/UDP/IP overheads. Is that work going to be 
> a part of MPLS WG? 
> IMO, RTP/UDP/IP is a lot of overhead, compared to VoMPLS 
> approach which actually serves the same purpose (at least in 
> bearer path)

This issue was addressed in the context of a BOF ("Voice Over IP Over MPLS 
(vompls)") held at IETF-47, March 2000.  There are meeting notes and slides to 
be found at http://ietf.org/proceedings/00mar/index.html.  Antti Kankkunen 
(then with Integral Access) and I were the co-chairs.

The disposition was rather complicated, but here's a quick summary.

There were 2 parts to the BOF:

One thrust was Voice over MPLS *without IP*, which the IETF rejected as not 
within the IETF charter.  This was a push from Integral Access, which was later 
taken to the MPLS Forum, where an implementation agreement was eventually 
approved for this approach.

The second thrust was VoIP over MPLS, where two proposals were made for 
RTP/UDP/IP header compression, the 'simple' approach from Swallow and Berger, 
and another more complicated approach from Berger.  Both of these approaches 
were presented to the BoF and to the MPLS WG, and were both accepted by the 
MPLS WG for further development (as well as MPLS WG charter extension).  
However, the work on these drafts didn't continue, for unclear reasons, and 
they expired.  

Swallow's 'simple' approach is being brought back again in one of the current 
drafts 
http://www.ietf.org/internet-drafts/draft-ash-e2e-vompls-hdr-compress-00.txt.

Hope this helps.

Thanks,
Jerry Ash