Re: [v4tov6transition] [Softwires] ISP support of Native IPv6 across NAT44 CPEs - Proposed 6a44 Specification

Brian E Carpenter <> Tue, 05 October 2010 20:49 UTC

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Date: Wed, 06 Oct 2010 09:50:31 +1300
From: Brian E Carpenter <>
Organization: University of Auckland
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Subject: Re: [v4tov6transition] [Softwires] ISP support of Native IPv6 across NAT44 CPEs - Proposed 6a44 Specification
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On 2010-10-05 22:26, Rémi Després wrote:
> Hi all,
> Draft-despres-softwire-6a44-00, coauthored with Brian and Sheng, has just been posted (
> It describes a solution for ISPs to offer native IPv6 across IPv4-only CPEs (NAT44 CPEs).
> It results from convergence discussion between authors of draft-carpenter-6man-sample-00 and draft-despres-softwire-6rdplus-00, taking into account comments made by authors of draft-lee-softwire-6rd-udp-01, and those made other Softwire WG participants since IETF 78.
> It is submitted to become, after discussion in the WG, a Softwire I-D.

By the way, we do discuss in the draft why it's a useful alternative to
both tunnel brokers (such as Hexago and SixXs) or Teredo. We don't
explicitly discuss why we think it's also a useful alternative to an L2TP
solution, but the arguments are, I think, similar to those for the tunnel
brokers (apart from our "hobbyist" comment).