Re: [Cfrg] RG Last Call - draft-irtf-cfrg-ocb-00

"Blumenthal, Uri - 0558 - MITLL" <> Wed, 06 February 2013 16:24 UTC

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From: "Blumenthal, Uri - 0558 - MITLL" <>
To: Greg Rose <>, "Igoe, Kevin M." <>
Date: Wed, 6 Feb 2013 11:24:37 -0500
Thread-Topic: [Cfrg] RG Last Call - draft-irtf-cfrg-ocb-00
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Subject: Re: [Cfrg] RG Last Call - draft-irtf-cfrg-ocb-00
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I concur with Greg.

My opinion is - this mode is technically sound (and that's probably is
this group's consensus) but practically unusable in any serious product
(commercial or otherwise) because of its licensing terms.

This licensing makes me leery to accept this AEAD mode for standardization
(despite that it is faster than the alternatives) when we already have
acceptable standardized non-encumbered (and reasonably fast) modes such as

Performance isn't all, after all. :-)
Uri Blumenthal

On 2/6/13 10:42 , "Greg Rose" <> wrote:

>On 2013 Feb 6, at 6:43 , Igoe, Kevin M. wrote:
>> There must be a statement in the abstract identifying it as the product
>>of the RG 
>>      How about this:  ³This document is a product of the Crypto Forum
>>Research Group (CFRG).²
>No, it isn't. I for one haven't even read it.
>> There must be a paragraph near the beginning (for example, in the
>>introduction) describing
>> the level of support for publication. Example text might read: "this
>>document represents
>> the consensus of the FOOBAR RG" or "the views in this document were
>>considered controversial
>> by the FOOBAR RG but the RG reached a consensus that the document
>>should still be published".
>>      Aside from IPR issues (sigh), there is nothing controversial here.
>> I suggest putting in a phrase
>>     like:
>>          ³OCB has received years of in-depth analysis previous to its
>>submission to the CFRG
>>            (see [4] and [5]), and has been under review by the members
>>of the CFRG for almost
>>            a year.  It is the consensus of the CFRG that the security
>>mechanisms provided by the
>>            OCB AEAD algorithm described in this document are suitable
>>for use in providing privacy
>>           and authentication.²
>>     You might want to add a reference that isn¹t behind a paywall, say
>>IACR ePrint 2001/026.
>Knowing the background and the authors, I can go along with "consensus".
>But in some standards bodies (I don't actually do all that much with IETF
>so I don't know the true position here) the word "consensus" has a
>defined meaning. I'm not sure we correctly can use it...
>Cfrg mailing list