Re: [Cfrg] Request For Comments: OCB Internet-Draft

Peter Gutmann <> Thu, 14 July 2011 03:49 UTC

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From: Peter Gutmann <>
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Date: Thu, 14 Jul 2011 15:48:49 +1200
Subject: Re: [Cfrg] Request For Comments: OCB Internet-Draft
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Ted Krovetz <> writes:

>I have just submitted an internet-draft for OCB to the IETF.

OCB is a nice mode, I've always wanted to use it, but:

>There are several patents that may apply to OCB. We are in the process of
>trying to get all parties to pool their patents and liberalize their use.

without the ability to use it without encumbrance I'll stick with CBC+HMAC or
GCM.  I know you can use OCB under the GPL but that's too much of a hassle to
try and sort out for each user, it'd have to be completely unencumbered to
make it useful.

(I'm not saying this out of some rabid anti-patent position but purely an 
anti-headache position, since there are unencumbered, if less efficient, 
alternatives available I'll go with those and avoid the hassle).