hi,
There's nothing gained by increasing the input entropy (compressing
http://www.itl.nist.gov/fipspubs/fip180-1.htm For t = 0 to 79 do TEMP = (A)<<5 + f(B,C,D) + E + Wt + Kt; E = D; D = C; C = B<<30; B = A; A = TEMP; Thats what I meant by the compression function. I am not trying to increase the input entropy. I was looking for such a compression function such that the chances of collision in the message digest obtained by hashing these 2^80 messages is collision free or very low probability of collision or in other words I dont want the birthday attack to work on it. If i hash 2^80 messages they should be equidistibuted in such a manner that it does not affect the security of the algorithm. --- "Major Variola (ret)" <mv@cdc.gov> wrote:
At 11:18 PM 7/7/03 -0700, Sarad AV wrote: A block cipher has the property that any one bit difference in input will change half the output bits on average.
thank you. Sarath. __________________________________ Do you Yahoo!? SBC Yahoo! DSL - Now only $29.95 per month! http://sbc.yahoo.com