Re: [multipathtcp] potential MPTCP proxy charter item

Joe Touch <> Mon, 07 November 2016 15:56 UTC

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To: Mirja Kühlewind <>,
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From: Joe Touch <>
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Date: Mon, 07 Nov 2016 07:56:20 -0800
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Subject: Re: [multipathtcp] potential MPTCP proxy charter item
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On 11/7/2016 7:42 AM, Mirja Kühlewind wrote:
> Do you mean the MCP forwards the original SYN (and basically does nothing if the server supports MPTCP) or does the MCP terminate the TCP connection and start a new TCP connection with MP_CAPABLE towards the server?
> Mirja
If you're OK with needing to terminate a failed option exchange, then it
might be possible to use EDO in the SYN in its current form.

TCPM decided to prohibit that in the general case, but I could ask them
to allow that in very limited environments (but it could NEVER be
default on).

Note - the use cases I'm hearing appear to assume very strong knowledge
about the other end of the connection and the path. In that case, you
probably can skip most - if not all - of the 'negotiation' options and
just start using them during the SYN too. However, if you say "no, we
need to confirm", then you would not be able to use EDO inside the SYN.