I've been a bit out of touch with the subject for a while, so could someone please bring me up to speed in the state of the art of DES bitslice. In particular, what are the best gate counts for the S-boxes? About a year ago I produced S-boxes with the following counts S-box S1 S2 S3 S4 S5 S6 S7 S8 Gates 95 84 89 77 96 87 86 88 (You can download them from http://www.cs.mu.oz.au/~mkwan/bitslice) However, I was recently told that these have now been beaten by a significant margin. I thought about it for a while, and came up with some ideas that should improve the count, but I'd like to know what I'm aiming for. Any improvements I make will also be made freely available, so you have an incentive to help me ;-) mkwan