Re: [quicwg/base-drafts] use key update for confirming the handshake (#3141)

Martin Thomson <notifications@github.com> Thu, 24 October 2019 04:10 UTC

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Subject: Re: [quicwg/base-drafts] use key update for confirming the handshake (#3141)
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@kazuho, the problem I'm concerned about is asymmetry around this new proposed condition.

This doesn't work because you establish a discard point that is reliably "synchronized" between endpoints.  You require that the key update is initiated, but don't require that the endpoint keeps sending packets until they are acknowledged.  Without that, you can end up in a state where an endpoint can reach the point of key discard too far ahead of its peer.

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