On Friday 26 September 2003 20:35, Edward J. Huff wrote: > On Fri, 2003-09-26 at 12:08, Gordan wrote: > > Of course, if the hashing function is complex enough to take 1 second to > > calculate on modern hardware, then it will take 136 years of CPU time to > > work out every possible combination. However, this could be narrowed down > > considerably by only checking known fertile IP blocks, e.g. South > > America, Far East, etc. > > Remember these guys have thousands of machines ready to do exactly what > they tell them. It works out to a few weeks, even allowing for > redundant calculations and the need to run at low priority.
Whoever would have thought that spammers would end up contributing to development of distributed computing applications... ;^) > It > certainly doesn't require much memory per system, so running it > in the background ought to be unnoticeable by the owner. Indeed. Unfortunately, legitimate email throughput would be limited by using complex/slow hashing functions. If your mail server can only check 60 hashes/minute, the chances are that your email throughput will not be much more than that even when taking into account hash cache optimizations. The problem is that if somebody has overwhelmingly more resources than you, you have no hope of success. He who has a fatter internet pipe / more CPU power (zombies count) wins. Unfortunate, but true. > Still, you could always change the hash function every day. That wouldn't help, unless the vast majority of open relays do not remain open for longer than the time it would take to effectively crack the hash keys. For some reason, I have a feeling that there are some open relays out there that have been open for years, but I could be wrong. Gordan _______________________________________________ Devl mailing list [EMAIL PROTECTED] http://dodo.freenetproject.org/cgi-bin/mailman/listinfo/devl
