Re: [multipathtcp] Timestamp option for Multipath TCP

Olivier Bonaventure <> Fri, 07 April 2017 18:59 UTC

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To: Christoph Paasch <>
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From: Olivier Bonaventure <>
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Date: Fri, 7 Apr 2017 15:47:44 +0200
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Subject: Re: [multipathtcp] Timestamp option for Multipath TCP
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>> 2. Define a new Multipath TCP option to carry timestamps. The utilisation of
>> this option would be included in Multipath TCP and thus no option besides
>> MP_CAPABLE would need to be included in the SYN.
> I like this approach, because it seems to me to consume less option-space.
> How would this timestamp look like in the DSS-option?

The DSS option has several flags that are unused. We could easily define 
two flags to indicate the presence of locally generated timestamp and 
echoed timestamp.

 > Would it still be 32-bits?
 > I think we can make it less than 32-bits, right?

I'm not sure that 32 bits would be required if the timestamp is only 
used for rtt measurements and not for PAWS.