[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: New AH Transform Drafts submitted

To: Robert Glenn <glenn@snad.ncsl.nist.gov>
Subject: Re: New AH Transform Drafts submitted
From: Steven Bellovin <smb@research.att.com>
Date: Thu, 20 Mar 1997 16:30:38 -0500
cc: ipsec@tis.com, rob.glenn@nist.gov
Sender: owner-ipsec@ex.tis.com

	 4. The Replay Prevention field is an up counter that starts at 1.  Act
	ually
	    this is kept from the previous specs.  The reason I mention it, is 
	that
	    it differs from the ESP-DES-MD5 spec.  I avoided using a negotiated
	    counter because of the complexity it adds and I'm not convinced
	    that starting at a fixed number weakens security.  I'm open to be
	    convinced.

My issue with the replay counter applies to ESP, not AH.  I know of no
weaknesses here.  The only possible issue is whether or not MD5 or SHA
are weaker if handed large numbers of 0-bits; I suspect not with this
few.

Prev by Date: RE: the COMPRESSION discussion
Next by Date: "Pillage first, then burn" - Attila the Hun
Prev by thread: New AH Transform Drafts submitted
Next by thread: "Pillage first, then burn" - Attila the Hun
Index(es):
- Main
- Thread