Re: [saag] The use of AES-192 and AES-256 in Secure RTP

[Lakshminath Dondeti <ldondeti at qualcomm.com>]

Hi Steve,

It all started with David's notes copy-pasted below:

++++++++
there has been some interest in using AES with larger key sizes in
Secure RTP, and some implementations have gone in this direction in
advance of any specification.  I wrote up an internet draft to fill
this gap (after trying unsuccessfully to get someone else to write
it :-) and to provide usage guidance and (eventually) test vectors.
+++++++

It looks like all we are doing at the IETF is to specify; business as 
usual :-).  We could add a recommendation along the lines you propose below.

regards,
Lakshminath

At 02:28 PM 5/3/2006, Stephen Kent wrote:
> I'm not a cryptographer, but I generally advise against encouraging 
> users to employ AES with 256-bit keys. The 256-bit key size is there 
> primarily as a hedge against the future development of quantum 
> computers. Since there are some performance costs with the use of 
> big keys, it seems unnecessary to adopt them at this time.
>
> Steve