On Tue, 7 Dec 2004, Tim wrote: > Due to the slowness of public key, most digital signatures are > performed on a digest of the original document. I think it's time to change the way we do digital signatures to compute several hashes of the original document using different algorithms (SHA1, MD5, ...) and sign the concatenation of the resulting digests. Does any standard signing software do this yet? Also, it's probably a good idea to alter in some small and unpredictable way anything that you're asked to sign. (Add some spaces, add text like "Signed by David F. Skoll", etc.) This makes it impossible to precompute two versions that hash to the same value, though it's still not very good protection if it becomes easy to find MD5 collisions. Regards, David.
