Re: [TLS] 0-RTT and Anti-Replay

Colm MacCárthaigh <colm@allcosts.net> Mon, 23 March 2015 04:32 UTC

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Date: Sun, 22 Mar 2015 21:32:14 -0700
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From: =?UTF-8?Q?Colm_MacC=C3=A1rthaigh?= <colm@allcosts.net>
To: Martin Thomson <martin.thomson@gmail.com>
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Subject: Re: [TLS] 0-RTT and Anti-Replay
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On Sun, Mar 22, 2015 at 8:35 PM, Martin Thomson
<martin.thomson@gmail.com>; wrote:
> For HTTP, I think we can use that first flight for idempotent queries
> quite easily and (at worst) the HTTP/2 connection preface.

This seems so open to error as to be untenable. Quite a lot of HTTP
based APIs are not idempotent, probably even the majority. Even where
API calls can be made idempotent in the theoretical sense, in the real
world there is often throttling and billing/metering state associated
even just with the raw number of calls made. So they are
non-idempotent by side-effect.

-- 
Colm