[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Size of IV field in DES-CBC mode
- To: Carl Muckenhirn <cfm@columbia.sparta.com>
- Subject: Re: Size of IV field in DES-CBC mode
- From: Steve Kent <kent@BBN.COM>
- Date: Tue, 03 Jan 95 15:07:47 -0500
- Cc: ipsec@ans.net
- In-Reply-To: Your message of Mon, 19 Dec 94 07:21:58 -0500. <9412191222.AA21960@columbia.sparta.com>
Carl & Phil,
If I remember correctly, FIPS 81 calls for an 8-byte IV for
CBC mode. One might have compliant implementations of DES that
do not allow the user to generate the IV and which require a full
8-byte IV. So, I'd recommend against trying to save 4 bytes.
Steve