IETF Logo Mail Archive

RE: comments on draft-ietf-ipsec-ciph-cbc-02.txt

Roy Pereira <rpereira@TimeStep.com> Wed, 18 March 1998 18:44 UTC

Received: (from majordom@localhost) by portal.ex.tis.com (8.8.2/8.8.2) id NAA05705 for ipsec-outgoing; Wed, 18 Mar 1998 13:44:21 -0500 (EST)
Message-ID: <c=US%a=_%p=TimeStep_Corpora%l=TSNTSRV2-980318185406Z-1166@tsntsrv2.timestep.com>
From: Roy Pereira <rpereira@TimeStep.com>
To: 'Markku-Juhani Saarinen' <mjos@ssh.fi>
Cc: "'ipsec@tis.com'" <ipsec@tis.com>
Subject: RE: comments on draft-ietf-ipsec-ciph-cbc-02.txt
Date: Wed, 18 Mar 1998 13:54:06 -0500
X-Mailer: Microsoft Exchange Server Internet Mail Connector Version 4.0.995.52
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Sender: owner-ipsec@ex.tis.com
Precedence: bulk

The draft <draft-ietf-ipsec-ciph-cbc-02.txt> does mention that IDEA
should use 8 rounds.  It does however mention 4 rounds, so we'll take
that out of the draft.


>-----Original Message-----
>From:	Markku-Juhani Saarinen [SMTP:mjos@ssh.fi]
>Sent:	Friday, March 13, 1998 3:27 AM
>To:	Roy Pereira
>Cc:	'ipsec@tis.com'
>Subject:	RE: comments on draft-ietf-ipsec-ciph-cbc-02.txt
>
>
>> How many rounds do you suggest for IDEA?
>
>IDEA has eight rounds.
>
>4-round IDEA is a research toy, and should not even be called IDEA.
>X. Lai and J. Massey never proposed it for real-life applications.
>
>It apparently creeped into the drafts because Applied Cryptography
>says (2nd ed, p. 325): 
>
>  "(..) Currently the best attack against IDEA is faster than brute force
>   only for 2.5 rounds or less; 4 round IDEA would be twice as fast and,
>   as far as I know, just as secure."
>
>This does not reflect our 1998 knowledge.
>
>- mj
>
>Markku-Juhani O. Saarinen <mjos@ssh.fi>, SSH Communications Security Ltd
>
>

v2.43.4 | Report a Bug | By Email | System Status