Re: [dcp] Protocol Version number
Mark Handley <mjh@icir.org> Thu, 20 June 2002 19:21 UTC
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From: Mark Handley <mjh@icir.org>
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To: Alex Audu <Alex.Audu@alcatel.com>
cc: dcp@ietf.org
Subject: Re: [dcp] Protocol Version number
In-reply-to: Your message of "Thu, 20 Jun 2002 14:11:29 CDT." <3D1228E1.A5816439@alcatel.com>
Date: Thu, 20 Jun 2002 12:22:25 -0700
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>I noticed the DCP header portion is mising a protocol version field, >though section 4.6 makes reference >to "The version of DCCP". Can we add a version field in the protocol >header? It seems to be a waste of bits. There are a number of ways to evolve protocols. - If the packet formats need to change enough so that receivers or middleboxes would be confused, then you might as well use a different IP protocol number. - If the change is minor, then it's most easily done in a backward compatible way by adding a feature that is negotiated. - If the change is not so minor, a non-negotiable feature could be sent in the DCP request. - Finally, there are four bits in the DCP common header that are marked as MUST BE ZERO for this version of DCP. If we decide at some future point that we really need a version number, between one and four of these bits can be designated as a version number field. Neither TCP nor UDP has a version field. I think time has shown this to be a reasonable decision. Cheers, Mark _______________________________________________ dcp mailing list: dcp@ietf.org archives: https://www1.ietf.org/mailman/listinfo/dcp project: http://www.icir.org/kohler/dcp/
- [dcp] Protocol Version number Alex Audu
- [dcp] Comments and Question Re: DCP drafts Patrick R. McManus
- Re: [dcp] Comments and Question Re: DCP drafts Eddie Kohler
- Re: [dcp] rcp-response packet reserved bits Eddie Kohler
- Re: [dcp] sequence numbers on resend Eddie Kohler
- Re: [dcp] sequence numbers on resend Mark Handley
- Re: [dcp] sequence numbers on resend Patrick R. McManus
- Re: [dcp] sequence numbers on resend Eddie Kohler
- Re: [dcp] sequence numbers on resend Patrick R. McManus
- Re: [dcp] sequence numbers on resend Mark Handley
- Re: [dcp] Protocol Version number Mark Handley