[RC5] DES-II question

Ted Rathkopf trathkopf at bigfoot.com
Fri Mar 27 09:09:45 EST 1998

> > > I was just curious - how many "false positives" were there during
> > > DES-II contest? (I hope this information is not classified...)
> We check the first 8 bytes.

So, in 8 bytes there are 256^8 or 2^64 combinations of which 1 will be 
the correct combination of 8 bytes.

DES uses a 56 bit key, so of the 2^56 keys, 1 will be the correct key.

So, statistically, there should not have been ANY false positives.

If my math is wrong, somebody please correct me.

Ted Rathkopf - trathkopf at bigfoot.com

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