Subject: i-D: IPv6 Extension Headers Reserved Space

From: Hagen Paul Pfeifer <[email-masked]>
Date: Thu, 29 Sep 2011 16:32:01 +0200

Hello,

draft-pfeifer-6man-exthdr-res-01 proposes an idea to reserve a small area
of protocol numbers in advance. IPv6 extension headers (or protocols) which
use one of these numbers are forced to structure the extension header to be
formatted as outlined in pre-draft-ietf-6man [1]. This allows operating
systems to code these numbers in advance in the stack.

This enables two opportunities

1) future standardized extension headers can be deployed without being
dropped by older routers where the extension header isn't known
2) vendors can test experimental extension headers in their networks

Hagen

[1] http://tools.ietf.org/html/draft-ietf-6man-exthdr-04

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From: Suresh Krishnan <[email-masked]>
Date: Fri, 30 Sep 2011 10:32:20 -0400

Hi Hagen,
  This idea was discussed earlier in the 6man wg and was not accepted
for the following reasons.

a) The protocol number space is very precious. We do not want to
allocate any numbers out of this for extension headers that may never
materialize.
b) Almost anything that can be done using extension headers can probably
be done using destination options without breaking backward compatibility.

Thanks
Suresh

On 11-09-29 10:32 AM, Hagen Paul Pfeifer wrote:
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