That 164 mb/sec figure for RC4's speed better be a typo, because I can't even come close to that. I wrote an Assembler subroutine that encrypts a 32,768 byte block, and called it 65536 times on a 486/DX2-66, without doing any disk reads or writes.
First of all, is that megabytes, or megabits? I've forgotten how many instructions it takes to do RC4, but RC5 takes 8-10 per round per pair of words encrypted, so it should do about 1/2 bit per instruction for 16-round. Some processors can do more than one instruction per clock cycle, though loads and stores are usually a bit slower. But you only need to load two words every 128-160 clocks, which is easy on a pipelined machine. So maybe it's a typo, but it should be far faster than 164 kB/s. # Thanks; Bill # Bill Stewart, stewarts@ix.netcom.com, +1-415-442-2215