What do last week's hacker attacks on big commercial Web sites have in common with the search for life in outer space and a program called Napster?
If you're a conspiracy theorist, you'll take these hints and conclude that the headline-grabbing shutdowns of Yahoo!, Amazon, eBay, E*Trade and other victims were the work of sleep-deprived aliens. And that's as good a guess as any right now, because nobody knows whodunit.
But these three topics are related, in the sense that they illustrate that the Internet is a medium unlike any other -- an open community in which every member, for better or worse, has equal access to everyone else. This is the Internet's great strength and great weakness. When those computers are joined in a common purpose, they have the potential for good and evil, or both at the same time. Our biggest problem may be learning to live with this ambiguity.
First things first. To understand how the perps temporarily disabled Yahoo! and company, you have to know what the Internet is: a gargantuan web of computers that range from giant mainframes to home PCs, all of which are available to each other through unique electronic addresses. Nobody owns the Internet and nobody controls it -- when you hook a computer to the Net, all you're really doing is agreeing to abide by a set of common communication standards.
All computers on the Internet are equal, in the sense that each can get the attention of any other. That's what makes the whole thing work.
Obviously, I don't have to let you into my system, but if your computer sends mine a "U there?" message, my machine has to pay attention. It can always tell you to get lost, but if I'm not listening at all, I can't be part of the community. Zillions of these little messages float around every day -- they're the building blocks of Internet communication.
The people who pulled off the most recent attacks took advantage of this access and the fact that many of these connected computers have lousy security. They penetrated a bunch of these machines and planted tiny programs that did nothing but send millions and millions of little "hello" messages to Yahoo! and the other targets.
The victims' computers were bogged down processing this overload of routine traffic, and as a result, people legitimately trying to access their Web sites couldn't get in. It's known in the trade as a Denial of Service attack.
Because the attacking messages came from everywhere at once, often with fake return addresses, they were almost impossible to trace. When they could be tracked down, they usually came from computers whose owners had no idea they'd been hijacked.
If the Internet hadn't been designed as an open community, the hackers couldn't have commandeered those computers for the attack. Nor would the victims have had to pay attention to the flood of messages that brought their operations to a halt. But that's the way the Internet is. If you have malicious intent and enough skill and patience, you can use it to ruin someone's day.
Now consider life in outer space. For years, a Berkeley-based project called the Search for Extraterrestrial Intelligence (SETI) has been combing through intergalactic signals collected by the giant Aricebo Radio Telescope in Puerto Rico, looking for patterns that could indicate the presence of life elsewhere in the universe.
It's a serious effort by serious scientists. The problem: They don't have enough computing power to analyze the torrent of data that pours in. So last year a group decided to tap the collective computing power of the Internet and the Seti@Home project was born (www.seti.org).
The scientists asked volunteers with home and office PCs to download a program that would grab a chunk of data from SETI's servers and use their computers to crunch the numbers in the background. When a PC gets through with its portion, it automatically uploads the results to SETI, downloads another chunk, and goes to work in the background again.
So far, more than 1.6 million PCs in 224 counties have been enlisted, giving the underfunded project more processing power than the world's largest supercomputers. SETI's scientists may never discover E.T., but now they have the wherewithal to find him if he's out there -- thanks to the open design of the Internet.
Now to Napster, which has nothing to do with sleep but everything to do with music. This program, which has taken college campuses by storm (and been banned by many as a bandwidth hog), lets users connected to the Internet share their MP3 files with anyone running the same program.
Napster turns the Internet into one enormous disk drive full of music that users can search by title or artist. If you find a tune you want, you can download it from the owner's PC. If someone finds a song they want on your machine, they can download from you.
The last time I checked, the communal library held more than 217,000 songs. This is an amazing triumph of technology, except for one little problem: Most of the tunes are copyrighted tracks from record albums, and transferring them to someone else is against the law.
The recording industry is suing to shut down Napster's servers, which don't store or transmit files themselves but act as a clearinghouse for the network. Napster says it designed the system to allow struggling artists to take their music public and build a following, and it can certainly be used that way. But it can also be used as a cheap if illegal way to avoid buying CDs.
So there you have it -- the good, the bad and the ugly. We're just beginning to realize the consequences of creating a technological community that's open to all, with collective power that dwarfs anything we've seen before.
In the words of that old Chinese curse, we live in interesting times.