91av

HAS your computer run out of processing power? Wouldn’t it be great if you
could just tap into someone else’s. Anyone else’s. This is the idea behind the
Grid. The name is borrowed from the US electricity grid, and the goal is to make
it as easy to access processing power over the Internet as it is to plug a TV
into the wall.

Once the Grid is up and running, users will be able to call on undreamed-of
resources simply by switching on their PC. Processing power, software and data
from computers across the world—all this will be at their fingertips. And
just like the electricity grid, it won’t matter where the juice actually comes
from.

“A tremendous amount of computing power is sleeping when the US is sleeping,
and when Europe is sleeping,” says computer scientist Fabrizio Gagliardi of
CERN, the European particle physics lab near Geneva. “If we could tap into that,
we could do very powerful things.”

Gagliardi is head of the Datagrid project at CERN, a grid that links
computers at 21 science and industry centres throughout Europe. Scientists at
CERN need the grid because in 2005 when they start smashing particles together
in their new accelerator, the Large Hadron Collider, raw data from the
collisions will pour out at a rate equivalent to a million feature-length movies
a second. Processing this data would swamp the CERN computers, so the
researchers need a way to share the burden. The Grid will help them to
distribute the data to computers across the continent.

Computer scientists in the US are working on a Grid of their own. The Grid
Physics Network (GriPhyN) links 16 universities and will be used to crunch data
from four major physics projects, including two Large Hadron Collider
experiments. Last month, the National Science Foundation awarded $11.9
million to the universities of Chicago and Florida to pursue the project.
GriPhyN should be up and running by 2005.

Managing shared resources isn’t easy, and the developers’ immediate task is
to develop a layer of software called “middleware” to keep order on the grid.
“The middleware is the guts of it. It is the broker that goes out and finds what
is available,” says Chris Jones, head of technology transfer at CERN. This
software also ensures that all the computers are speaking the same language. “It
allows me to identify myself,” says Gagliardi. “It establishes a secure
connection, so I can be charged. It asks: where are the resources? It looks for
the best way to do the job. It will also predict how long the job will take, and
how much it will cost.”

It is possible to gain access to other computers at the moment, but
incompatible systems and languages, bureaucratic rules and suspicious network
administrators make it complicated. A pervasive Grid would change all that. “All
the authentication, looking for appropriate data, software, space and payment
will happen automatically, without us seeing it,” says Carl Kesselman from the
University of Southern California in Los Angeles. Kesselman, along with Ian
Foster from the University of Chicago, introduced the concept of the Grid in
1996. Both are now working on GriPhyN. In ten years, they say, we will all be
part of one giant, global Grid.

If they’re right, it won’t be long before we can access the Grid at home,
simply by installing middleware on a PC and linking up to an ultra-fast network.
But what would we use it for? “We are still trying to realise what the
technology is really good for,” Kesselman admits. Foster sees working or playing
together as the killer applications. “What people really like to do is
communicate,” he says. “It is those applications, for example interactive gaming
or tele-immersion, that will really take off.” Such activities require huge
amounts of processing power and will only be possible if you can siphon it off
the Grid.