RE: Two AES encryption modes?

["David A. Mcgrew" <mcgrew@cisco.com>]

Gregory,

> -----Original Message-----
> From: owner-ipsec@lists.tislabs.com
> [mailto:owner-ipsec@lists.tislabs.com]On Behalf Of Gregory Lebovitz
> Sent: Wednesday, July 24, 2002 6:34 PM
> To: 'Paul Hoffman / VPNC'; ipsec@lists.tislabs.com
> Subject: RE: Two AES encryption modes?
>
>
> If AES-CTR comes to fruition quickly, can someone put forth an
> argument for
> continuing to use AES-CBC?
>
> (To clarify, I am not challenging us to drop AES-CBC, I just want to hear
> cryptographers explain why we would/would not need both).

One consideration is the fact that draft-ietf-ipsec-ciph-aes-ctr-00.txt MUST
NOT be used with manual keys.

David