(IANAL, and I'm not even attempting a lay interpretation of the _legal_ issues in this message) thad writes:
But, what about copyright? Now, copyrights cannot protect ideas, only the expression of those ideas. An algorithm is clearly an idea, you could write a program that would implement it in a completely different way, not just by translating it (translations are still protected by copyright).
RC2, though, as 256 bytes of seemingly random data at the head of it, in a permutation table. This is clearly not any idea, but a bit of text. This text would have to be copied to any interoperable RC2. (You could surely use some different permutation, and probably most of the 256! permutations would be equally secure, but would not interoperate with RC2). I would expect that this copying of text be held to be a violation of copyright.
From a technical perspective, I can't say that the permutation table is "clearly not an idea", although that view has some significant allure. I think many cryptographers would agree that the S boxes in DES represent some pretty weighty ideas indeed, and constitute an intrinsic part of the algorithm. Offhand the precise construction of the RC2 permutation table doesn't seem to me to be nearly as important to the strength of RC2 as the S boxes are to DES' strength. I'm certainly no expert. But I'm a little hesitant to dismiss the specified table as "a bit of text".
Do you think the table would be more like an idea if it turned out to be determined by pi ? (not a rhetorical question) -Lewis <lmccarth@cs.umass.edu> `I went down to the demonstration/ to get my fair share of abuse/ singing we're gonna vent our frustration/ if we don't, gonna blow a 50A fuse" -Nanker Phelge