Re: [multipathtcp] MPTCP Schedulers

Zhen Cao <> Sat, 23 March 2019 20:39 UTC

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From: Zhen Cao <>
Date: Sun, 24 Mar 2019 04:38:58 +0800
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To: Olivier Bonaventure <>
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Subject: Re: [multipathtcp] MPTCP Schedulers
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Hi Olivier,

> Yes. In the hybrid access networks use case, the schedulers are
> optimised to first use the DSL network and then overlfow over the LTE
> network when the DSL is full.

We also have a similar case where the server would like to saturate
WLAN and then overflow to LTE, where another scheduler will be needed.

But  we at least have two design choices here:
1) first one, as you said, the fine-grained remote control of the
schedulers used on the peer.
2) extension of the spare space before the Backup bit in
MP_JOIN/MP_PRIO.  That's, keep the current Backup bit as it is( use
the backup flow only in the event failure).  And in the meantime use
the spare bits as the ‘Saturate and Overflow(S&O)’ priority bit; The
server who receives sub flows marked with S&O, will first saturate the
prioritized subflow and then overflow to the others.

I am in favor of the second one if the cost based prioritizing is only
case we want to solve, and the priority can be expressed as binary.
This does not need new options space for MPTCP anyway.