[tcpm] draft-gont-tcpm-tcp-timestamps-00
Alfred Hönes <ah@tr-sys.de> Tue, 13 January 2009 23:18 UTC
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From: Alfred Hönes <ah@tr-sys.de>
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Date: Wed, 14 Jan 2009 00:16:29 +0100
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Subject: [tcpm] draft-gont-tcpm-tcp-timestamps-00
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Folks, I have reviewed the I-D, draft-gont-tcpm-tcp-timestamps-00, which has been submitted to the WG for consideration. The basic idea in the draft seems to be so logical and such an immediate step forward in the spirit of RFC 1122 that, if the TCP timestamps option already had been defined during the development of RFC 1122, I suspect that it readily would have been incorporated and recommended therein! Besides a small couple of textual flaws and improvement requests I already have communicated off-list to the author, there seems to be a double oversight in the second part of the algorithm in section 3: a) There's no "Otherwise, ..." clause. Fix: Copy the sibling clause literally from the end of the first part of the algorithm to the end of the second part! b) The following (potentially rare) corner case, in which it would have been possible according to the rules in RFC 1122 to establish a new connection notwithstanding a previous incarnation in the TIME-WAIT state, has not been considered: - old connection didn't use TSO, - new SYN segment with TSO, - local policy / socket options would lead to SYN-ACK without TSO, - new incoming Sequence Number > last corresponding old SN Including this case into the second alternative of the second part of the algorithm would therefore further improve the benefit of the algorithm. It might be preferable to make the answer to the question 'would the new connection be using timestamps?' the primary criterion for distinguishing between the first and the second alternative in the second part of the algorithm. Doing so would allow to simplify the text otherwise necessary to describe the preconditions in the second alternative. I have submitted ot the author some possible text variants to accommodate these considerations and discussed their mutual benefit. For the sake of brevity, I have omitted the details here, shortly ahead of a promised update to the draft. Best regards, Alfred. -- +------------------------+--------------------------------------------+ | TR-Sys Alfred Hoenes | Alfred Hoenes Dipl.-Math., Dipl.-Phys. | | Gerlinger Strasse 12 | Phone: (+49)7156/9635-0, Fax: -18 | | D-71254 Ditzingen | E-Mail: ah@TR-Sys.de | +------------------------+--------------------------------------------+ _______________________________________________ tcpm mailing list tcpm@ietf.org https://www.ietf.org/mailman/listinfo/tcpm
- [tcpm] draft-gont-tcpm-tcp-timestamps-00 Alfred Hönes