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Re: [IPsec] DDoS puzzle: PRF vs Hash

Paul Hoffman <paul.hoffman@vpnc.org> Mon, 09 February 2015 00:44 UTC

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From: Paul Hoffman <paul.hoffman@vpnc.org>
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Date: Sun, 08 Feb 2015 16:44:07 -0800
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To: Yaron Sheffer <yaronf.ietf@gmail.com>
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Subject: Re: [IPsec] DDoS puzzle: PRF vs Hash
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On Feb 8, 2015, at 3:21 PM, Yaron Sheffer <yaronf.ietf@gmail.com> wrote:
> Yes, of course. It just needs to verify the integrity (MAC) of the received ticket (as easy or easier than our proposed puzzle verification), and then the rest of the exchange is lighter-weight than a typical IKE exchange. See http://tools.ietf.org/html/rfc5723#section-4.3.2.

I knew the latter part, but I was more concerned about the former. As long as the verification is no harder than the proposed puzzles, then yes, resumption seems like a good addition. I wanted to be sure that it wasn't harder.

--Paul Hoffman

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