Re: [tcpinc] WGLC for draft-ietf-tcpinc-tcpeno

David Mazieres <> Wed, 22 February 2017 18:58 UTC

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From: David Mazieres <>
To: Wesley Eddy <>,
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Date: Wed, 22 Feb 2017 10:58:51 -0800
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Subject: Re: [tcpinc] WGLC for draft-ietf-tcpinc-tcpeno
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Wesley Eddy <> writes:

> 1) edge cases where you're communicating with non-ENO hosts, that do not 
> discard data on SYNs (for whatever reason), and may pollute the data 
> stream delivered to the application, breaking the goals of TCPINC to 
> work without impacting the application's TCP mapping
> 2) cases where other TCP extensions (perhaps yet to-be-defined) do 
> something in conflict with that data

Can you make concrete suggestions for wording changes?  In particular,
we intended to address the points you raised with the following language
of section 4.7:


        If a host sends a SYN-only SYN+ENO segment bearing data and
        subsequently receives a SYN-ACK segment without an ENO option,
        that host MUST reset the connection even if the SYN-ACK segment
        does not acknowledge the SYN data...

        To avoid unexpected connection resets, ENO implementations MUST
        disable the use of data in SYN-only segments by default.


        More specifically, a host that implements ENO MUST discard the
        data in a received SYN+ENO segment if any of the following
        * The SYN segment contains a non-empty TFO option or any other
          TCP option implying a conflicting definition of SYN data.

If those aren't clear, the question is how to make them so.