[tcpm] draft-moncaster-tcpm-rcv-cheat-02 probabilistic test
John Heffner <jheffner@psc.edu> Wed, 14 November 2007 16:57 UTC
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Date: Wed, 14 Nov 2007 11:57:04 -0500
From: John Heffner <jheffner@psc.edu>
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Subject: [tcpm] draft-moncaster-tcpm-rcv-cheat-02 probabilistic test
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Toby, I'm not sure I completely understand some of the claims in Section 6.2.2, particularly: "That is to say, a receiver can either honestly report the missing packets or it can suffer a reduced throughput by delaying segments and increasing the RTT," and "Equally, a receiver that delays transmission of the duplicate acknowledgements until it is sure it is being tested will leave an obvious pattern of acknowledgements that the sender can identify." If I were designing a receiver to try to defeat this test, I would delay response by six segments, or a short timeout, whichever is less. If I observe reordered segments, I would send the ACK/SACK that the sender would expect. Additionally, I would ACK any lost segments, and any received segments as normal, only delayed by the time to receive the following six segments. You seem to have thought about this strategy, but I'm not sure I see how the claims in section 6.2.2 apply. I don't think this strategy will increase the RTT so much that it will cause significant performance reduction. And I'm not sure how delaying the ACKs will leave an obvious pattern that the sender can identify. Am I missing something? -John _______________________________________________ tcpm mailing list tcpm@ietf.org https://www1.ietf.org/mailman/listinfo/tcpm
- [tcpm] draft-moncaster-tcpm-rcv-cheat-02 probabil… John Heffner
- [tcpm] RE: draft-moncaster-tcpm-rcv-cheat-02 prob… toby.moncaster
- [tcpm] RE: draft-moncaster-tcpm-rcv-cheat-02 prob… Alfred Hönes
- [tcpm] Re: draft-moncaster-tcpm-rcv-cheat-02 prob… John Heffner