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SETI@Home to Crunch More Data
BigDave writes: "In this article on Wired, it describes how SETI is gradually running out of data, as the current data acquisition system cannot keep up with the rate of processing (since they now have 3 million users processing data). They have acquired a new high-speed digital data recorder which is Linux-powered, and was donated by Hewlett-Packard."
Maybe they could help out the STI Project
-Yarn - Rio Karma: Excellent
I've been thinking about the whole distributed computing issue recently. SETI@Home and Distributed.net have proven how effective large scale parallel processing is. OTOH, Nimda has proven how effective a very simple worm can be.
Joe Cracker just managed to get ahold of a password file from his favourite .mil site. But now he's stumped. He tried his regular password cracking programs, to no avail. He decides to code up a quick worm in Visual Basic, and in several hours he has thousands of computers working at his task.
They've cracked the DES-I, DES-III, RC5-56, and CSC encyption contests, and now they're alternating between cracking RC5-64 and finding optimal golomb rulers.
When will they start on rot13?
Maybe the Seti@Home project should consider re-crunching old data. Versions 3+ perform a LOT more calculations than 2.x or 1.x versions of Seti@home. How about adding a new 3.x version, that will only calculate the uncalculated portion of old data in the existing system.
===> An eye for an eye makes everyone blind - MG
All newer transmissions systems, from SSB to spread-spectrum to GPS to HDTV, don't use carriers. The FCC wouldn't license a transmission system today that used a carrier. In time, all radio will be carrierless, to save spectrum space. That date is probably about 20 years away, after the transition to HDTV and digital audio broadcasting. So for less than a century will our civilization have broadcast carriers. That's a narrow window to hit when looing for another civilization.
There's some redundancy in all carrierless systems, but it may be only a few percent, and it's hard to find if you don't know how to look for it. Typically, detecting a spread-spectrum signal involves trying to synchronize a psuedorandom number generator at the receiving end with the signal. This is hard when you have no idea what the psuedorandom number generator looks like. It's not impossible; it's a cryptographic problem. But it's hard to detect a signal so weak you can't read the bits.
You can look for the presence of a carrier so weak that you can't detect the modulation, by averaging over many cycles. That's what SETI@Home actually does. So if there are carriers out there, SETI@Home should find them. But unless someone is deliberately beaming carriers at us, there's nothing to find.
I've met some of the SETI@Home people, and they admit this problem. By now, if anybody in our stellar neighborhood was aiming high-power continuous carriers at us, we'd know it. But there could be signals encoded in more efficient ways and thus look like noise. SETI@Home will never find them.
I think that the SETI@Home effort should be devoting more resources to finding non-carrier signals. Maybe long-period autocorrelation, looking for repeats of bit patterns, would be more appropriate than the present carrier search. Something that sounds like stellar hiss might turn out to have data in it.