Re: Addition to SHS...?

Roger Schlafly wrote:
> 
> "Kim Hyldgaard" <[EMAIL PROTECTED]> wrote
> > What the reason for specifying a 224? - Obviously one could think of
> > computation speed, but since it's based on 256?
> 
> It is an odd announcement. There is an official NIST elliptic curve of
> that size, but there are other sizes as well, and usually truncation is
> necessary.

They plan to use those 32 bits for something else?

It could be an backward compatibility issue: by taking the 32 bit token
from the signature field they can fit it in existing protocol specs. A
similar idea has been proposed to counter the Barkam-Biham-Keller attack
against GSM A5.

-- Lassi