Distributed computing

Posted at: Tuesday 29th June 2004 by Ian Betteridge

You might just use your bog-standard 2.4GHz PC for writing inane messages to your friends, but it could become the most powerful computer in the world, or at least part of it. Ian Betteridge explains how

And ultimately, it could be your machine that finds evidence of extraterrestrial life, sequences the final part of the human genome or even finds an HIV vaccine. Distributed computing projects will, one day, undoubtedly make a major contribution to science and actually save lives, and it could be your PC that puts the final piece of the jigsaw puzzle into place.

The future
It's easy to think of a future where distributed computing becomes so powerful that it makes supercomputers redundant. After all, how can even the most colossal single machine compete against the entire computing resources of the Internet? Even if they aren't using all of the processor's power, a distributed network with 500,000 simultaneous users can easily outpace the fastest supercomputer.

However, this ignores a fundamental problem with distributed computing, which is that it's only useful for tasks that can be split into small, discrete chunks that are easily passed around the Internet. Supercomputers such as the Earth Simulator, on the other hand, handle massive data sets that need to be passed between processors at extremely high speed. In many of the tasks for which supercomputers are built, such as simulating weather systems, it's the bandwidth available to transfer data between the memory and processor, and between processors themselves, that's the key factor.

But for many computing tasks, typically those involving database management and data processing, distributed computing allows companies to gain massive amounts of computer power for very little money. So it's no surprise that some companies, such as Base One International, have started to commercialise the idea by creating tools to harness the power of the hundreds or thousands of computers on employees' desktops to create a virtual supercomputer. Other companies, including Apple with its Xgrid software, have also cottoned on to the idea that many common tasks undertaken by large computers can alternatively be hived off to desktop machines, resulting in faster performance and lower costs.

In the early 1960s, Ross Perot realised that there were a lot of computers in the world. He also realised that, for most of the time, they were sitting doing nothing. So he set up a business, called Electronic Data Systems (or EDS), that bought time on people's computers when they weren't using them (usually at night), and sold it as a data processing service to companies unable to afford a computer. EDS employees would appear at a company in the middle of the night with a truckload of data tapes, run their programs and disappear by morning to deliver the results to their happy customers.

Modern distributed computing has already started to go commercial, and, although Popular Power, which was founded to commercialise distributed computing, has already folded, other companies are waiting in the wings. It may even one day be possible to get paid for the work that your computer does while you're asleep, or to get free hardware as long as you keep it working 24 hours a day, donating cycles to other people's projects.