The SETI@home search is a
parallel distributed computing project. All data is independent of one another
because each work-unit represents some frequencies from a small section of sky
and, to process the data, the computer doesn't need information about the other
work-units. Thus, each user gets a different piece of the sky for their computer
to analyze. SETI@home has three servers, dubbed Sagan, Asimov, and Cyclops.
Sagan sends out the work units while Cyclops and Asimov have database servers
that keep track of interesting data. (Rheingold 178) Sagan stores all work unit information
received from Arecibo, which is useful if a specific work-unit needs to be spliced
and sent out again. This would happen if a computer stops using SETI and never
sends in the completed work-unit; SETI can easily send that unfinished work-unit
to another user.
The SETI@home project also
has some unique differences from other distributed computing projects. It uses
a closed-source client in order to protect the data since it would be detrimental
to the project if data was altered. The SETI project is also finite; there is
only so much sky that can be seen from the Arecibo telescope. Other projects,
such as the PiHex project and the Great Mersenne Prime Search (GIMPS) are infinite,
as Pi could — with enough computer power — be calculated to a trillion places.
The GIMPS project could also continue for quite some time since there is an
infinite number of primes.
SETI@home is slated to run
for only two years. By then, the entire amount of sky that can be seen from
the Arecibo telescope will have been analyzed three times. The SETI scientists
hope that, at the project's completion, there will be new technology and new
techniques to analyze radio signals and search for extraterrestrial life. There
are also plans to create a SETI@home II, which might use a telescope in Australia
to expand the amount of data that could be analyzed. This project, too, would
utilize the computing power the Internet has to offer by taking advantage of
the concept of distributed computing.
©2000 Team DC (Thinkquest Team C007645). Hosted by ThinkQuest.