Re: [multipathtcp] Consensus call on potential MPTCP proxy work

Joe Touch <touch@isi.edu> Tue, 18 April 2017 21:56 UTC

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To: Yoshifumi Nishida <nishida@sfc.wide.ad.jp>
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From: Joe Touch <touch@isi.edu>
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Subject: Re: [multipathtcp] Consensus call on potential MPTCP proxy work
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On 4/18/2017 2:44 PM, Yoshifumi Nishida wrote:
> Hi Joe,
>
> It's not tunneling. The proxy converts a tcp connection into a mptcp
> connection and converts it back to a tcp connection (if necessary)
> So, it won't be tcp over tcp.
OK, but that's not proxying either.

That's (at best) connection hijacking.

> MPTCP will convey control data for application (proxy) in payload.
> But, MPTCP of course doesn't care the contents of payload. 
> It just carries data and app will parse the data. Putting data in SYN
> is trying to reduce the latency and no other meaning as far as I
> understand.

MPTCP is TCP. Putting the data in the SYN of a TCP connection is
hazardous. The goal is irrelevant.

I thought we went through this all when MPTCP was created, but it
appears insufficiently so.

Joe