Ah. By address space, you mean a set of possible keys, right? Is there specific software we use to test this 'address space,' or do we come up with our own? It seems that there ought to be a more exotic method other than a brute force attack. I don't know much about cryptography, but if there's a way to get "feedback" as to how "close" a key is to the real key, then some sort of genetic algorithm could be devised. Actually, perhaps not, since there are no "genes" envolved, just a big number. Hm. -- ================================================================= Tobin Fricke, Alias Light Ray dr261@cleveland.freenet.edu TobinTech Engineering KE6WHF Amateur Radio The Digital Forest BBS (714) 586-6142, 28800bps