The Grid: Computing power on tap

Herbert Blankesteijn

If I need some serious computing power for a short while every day, to play a game for instance or perform spreadsheet calculations, I may decide I need a faster computer. It will do hard work for a couple of minutes every day, and be idle otherwise. I wish I could have a part-time computer and spend only a fraction of the money. In the future this may be possible; in the world of science it's becoming a reality right now.

Over thirty years ago the foundations were laid for the current Internet. Computers at a handful of American institutions were connected by data links. In order to use them and access a remote database you needed to be skilled, and you needed to be authorized. It was nothing like pointing and clicking your way through the World Wide Web.

Now a similar revolution is taking shape. Computer scientists are discussing building a Grid, more or less on top of the Internet. The grid is supposed to help people, institutions and companies share computing resources. Like data, but the Internet does that to a large extent already. On the Web you can copy data (like text documents, graphics or software) from many remote machines. Or hard disk space, but this too is hardly new. People store data they will need while on the road, or set up homepages, on hard disk space on the internet. Often they don't even know where the disk space is located geographically.

What's really interesting and new is the idea of using somebody else's calculating power. Science is once again the inspiration. Remember that the World Wide Web, the clickable part of the Internet that attracted millions to networking, was invented at CERN by physicist Tim Berners-Lee when he was looking for ways to share data in an easy way. Now CERN faces some very serious computing work in the near future, when in 2005 the Large Hadron Collider - a particle accelerator - will barf up more data than a hundred thousand pc's can handle. CERN doesn't want to buy that much data processing machines. It wants to hire part-timers. And they are there.

There are millions of computers in the world, and most are switched on, but idle. Word processing is no hard work for a Pentium III. What if these could do some work for science? They do. A handful of scientific projects, like SETI, (Search for Extraterrestrial Intelligence) which looks for extraterrestrial messages in interstellar radio noise, have found volunteers willing to download and analyze raw data on their pc's. Intel saves tens of millions of dollars a year by dividing labour among idling computers, instead of buying new hardware. Some university departments do the same. There are even private companies that seek to make money by trying to match demand and supply of spare computing power on the Internet. The network is going to be the computer, as one computer company has been claiming for years.

It's a game for the skilled and the authorized so far, like in the early days of the Internet. Present gridlike initiatives all work in a different way. There is no way to plug into a wall socket, log on to an Grid provider, pay a fee and have your thing done. Scientists are now working together internationally to develop sets of rules called protocols that must govern the way the Grid will work. Protocols make sure all connected computers work the same way and understand each other. Similarly the Internet Protocol (IP) rules the Internet proper and the Hypertext Transfer Protocol (http) is the one language machines speak on the part of the Internet called the World Wide Web.

4-7 March 2001 Grid builders will meet in Amsterdam to discuss results and make further plans. If money is a measure, the work on the Grid is important. CERN has received 10 million euro from the EC, and the universities of Florida and Chicago got about the same amount, 12 M$, from the National Science Foundation. Those are just two examples - it's a multimillion dollar business.

If it becomes a reality the Grid will be a scientific tool for some time, as was the Internet. You won't be able to do much computing without a computer in the foreseeable future. But then again, someday you might.