Alun Anderson, editor-in-chief of the New Scientist, recently wrote "The smart-dust revolution" for 'The World In 2004' published by The Economist. In this extremely interesting article, he argues that for almost 40 years, our vision of progress in the computing world was to pack more and more power on silicon chips. Now, another information revolution is emerging, driven by billions of tiny and intelligent sensors able to self-organize into scalable and fault-tolerant networks. Taken individually, these sensors have small brains, but using billions of them is an entirely other story.
Here are some excerpts.
Big boxy computers that were state-of-the-art 20 years ago can now be made about the size of an aspirin. Very soon they will be the size of a grain of rice and, before long, a grain of sand.
Enter "smart dust": computers so small that you would not notice if one floated in through your window on the breeze (and, of course, the CIA has already spotted what that might do for them). They lie at one extreme end of the sensor revolution that sees a glorious future in combining sensors, limited intelligence and communication abilities in vast numbers of tiny computers.
Smart-dust advocates have visions of sending billions of these machines into the atmosphere so that the entire planet could be wired. Stupendous networks of communicating sensors would give the earth a digital nervous system accessible to the web and giant search engines, from which we could instantly access anything about the state of the planet, from changing weather to the state of forests.
At the other end of the sensor revolution are entirely practical applications that are just coming on the market. Already, new American start-up companies (among them Dust Inc, Ember Corporation, Millennial Net, Crossbow Technology and Intel Research) are creating highly practical devices that can sense, compute and communicate -- and make businesses more efficient.
The author gives some details of an experience conducted by the U.S. Army in which small sensors, called "motes," were used to collectively detect military vehicles traffic. He also looks at the radio-frequency ID tags (RFID) which sooner or later will be deployed in supermarkets and at how sensors could be used in "intelligent" buildings.
What is so clever about all this? In these new sensor networks, there are no wires, so installing sensors costs very little. Messages pass from one sensor to another using radio waves (or even laser beams), choosing whatever route is most efficient until messages reach the point where the information is to be picked up. By passing on messages via multiple, changeable routes, the network is self-organising, fault-tolerant and scalable -- it can easily be made to grow, shrink and change configuration.
Just as important, because the network operates through short-range hops, very little power is used. Unlike a mobile phone, which runs its batteries flat in hours while communicating with distant base stations, smart sensors can keep going for years.
Here is the conclusion.
With the ability to expand systems with sensors of every kind, the sensors web begins to look more like our own nervous system, where vast arrays of sensors for heat, touch, pressure and so on are embedded in our skin. Giving the earth a digital skin is just a vision now, but in 2004 it will start to seem less fanciful.
If you are interested by this subject, here is a list of related stories.
- The Smart Sensor Web, October 5, 2003
- UCSD Chemists Develop 'Smart Dust', August 26, 2003
- Spray-on Nanocomputers Are Coming, August 19, 2003
- Smart bricks could monitor buildings, save lives, June 15, 2003
- Will Wireless Networks Lead to Better Wines?, April 6, 2003
- Wireless Mesh Networks, March 1, 2003
- The Intelligent Swarm, February 14, 2003
Sources: Alun Anderson, The New Scientist, for 'The World In 2004' published by The Economist print edition, readable online via a H-P sponsorship; and various websites