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[quicwg/base-drafts] MIn_RTT management (#2923)

Gorry Fairhurst <notifications@github.com> Mon, 22 July 2019 20:56 UTC

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From: Gorry Fairhurst <notifications@github.com>
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Subject: [quicwg/base-drafts] MIn_RTT management (#2923)
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So, I understand that min_RTT is maintained per path as the minimum RTT. 
 
I foresee paths that persist for long periods and where the set of network devices forming the can path change, and hence the min_RTT can be "ridiculously" small concerned to the actual value had it been measured recently. I don't much like that min_RTT is never raised.

The solution could be simple. Re-initialise min_RTT from the RTT sample periodically. How often to reset is not critical, but needs to be reasonably often - I suggest every 600 secs.  (I'd be OK with other numbers, this is the default path state timeout in RFC1981).

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