Re: [quicwg/base-drafts] Clarify the side-effect of frequent key updates (#2788)

Kazuho Oku <notifications@github.com> Thu, 13 June 2019 09:19 UTC

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Subject: Re: [quicwg/base-drafts] Clarify the side-effect of frequent key updates (#2788)
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Thank you for the discussion.

While we agree that excessive use is key update is something unnecessary, I think you are correct in point out that an endpoint is expected to process an incoming packet protected by a newer generation of key, presumably be comparing the PN of the incoming packet and the highest PN and epoch of the packet received previously.

That’d make this PR worthless with the exception of the removal of the MAY requirement on the number of the send keys.

Thank you for the discussion.

OTOH, this means that we need to discuss if and how we need to prevent excessive key updates being used as a DoS vector...

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