2008/10/16 Arnaud Ebalard <[EMAIL PROTECTED]>: > Hi, > > Suresh Krishnan <[EMAIL PROTECTED]> writes: > >> Hi Folks, >> We have resolved all the issues raised during the last IETF meeting >> in the latest version of this draft. We would like the people who had >> issues with the earlier versions of this draft to check if they are OK >> with the changes. The latest version of the draft is available at >> >> http://www.ietf.org/internet-drafts/draft-krishnan-ipv6-exthdr-06.txt > > First, a typo: > >> 4. Exceptions >> >> The the Generic IPv6 extension header is generic enough that it is > > ^^^^^^^ > > Then, a comment: > > This is version 6 of the draft but I only found a single comment in the > mailing list archive so my question below may already have been done > during a meeting or privately. > > Instead of creating a new specific header type and a specific registry > for new allocations, I wonder if it would not be easier (for everyone, > AFAICT) to just consider: > > - *currently* existing headers : implementations will have to cope with > those ones. > - future header: force those to be in the common TLV format (1-byte NH, > 1-byte Length, Data) > > In the end, instead of defining "An uniform format for IPv6 extensions > headers" using a new specific type, wouldn't it be easier to just force > future definitions of extension headers to follow the common layout > proposed below. What were the arguments raised privately or during > meetings not to follow that path?
One of the issues is the "cross-pollution" of IPv6 header number space and IP protocol number space. IPv6 headers are indistinguishable from higher layer protocols. I'm thinking of a new end-node header that a firewall might block for lack of recognition when in fact the higher layer protocol might be recognizable (TCP, UDP, ...). With the introduction of a separation between the two more policy choices become possible. -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
