Computer Viruses Can Be Healthy for Innovation
The Melissa virus has struck, trailing in her wake an increasingly familiar chorus of admonitions about the dark underside of our technological revolution--warnings that the sophistication of computers today and the scale of the Internet make us uniquely vulnerable to these mysterious threats.
Yet one could also argue that computer viruses are pretty much as old as the computing networks that make them communicable--and that they can teach us valuable lessons as well as threaten us with calamity.
For proof, one need only go to the birthplace of the field: Xerox’s Palo Alto Research Center. The legendary Xerox PARC gave us not only the first personal computer, the first graphical user interface and the first laser printer, but arguably the first virus.
John Shoch, the inventor of this pioneering entity, would hardly enjoy being called the father of the virus, for his dynamic, roaming program known as the “worm” was designed not to destroy or damage computer systems but enhance them. Nevertheless, one night in 1978 Shoch’s worm got loose in PARC’s internal network, setting him and a handful of colleagues on the first desperate virus chase.
Shoch, now a venture capitalist in Silicon Valley, was a PARC engineer working on his Stanford doctorate when he created the first worm. The program took its name from the “tapeworm,” a program that appeared in John Brunner’s “The Shockwave Rider,” a popular science-fiction novel of the time, in which it is used by the hero to destroy a sinister computer network.
The PARC worm’s purpose was at first much more modest: to save Shoch hours of tedious scut work.
Shoch’s doctoral research was an analysis of the traffic patterns of PARC’s pioneering Ethernet, which linked about 200 of its Altos, the personal computers its engineers invented in 1973. His idea was to arrange for about 100 of the machines to spew digital bits into the Ethernet simultaneously, then measure how much electronic gridlock ensued. Rather than load the same program individually into every machine, he devised the worm to do the loading automatically by seeking out idle Altos and transmitting the test program by wire to all those that signaled they were available.
Thanks to the worm, he told me later, “you could send out a ‘Hello’ to any free machine and say, ‘I’m going to load this program on you through the net, and when I say “Go,” you’re to start generating bits onto the network. Then I’m going to take back all the data and make a printout. And then I’m going to produce this chart and get my PhD.’ ”
That test proving successful, he soon turned his thoughts from communicating directly with each machine to instructing them to talk among themselves. What if, rather than loading the same program onto 100 machines from one central point, he gave each machine the ability to seek out others, passing the program on from one to another?
The possibilities were infinite. Shoch imagined PARC’s Altos not as 200 computers, but as a single meta-computer with 200 processors, all linked via the worm. Shoch’s brainstorm hinted at a method of compounding processor power that would one day find wide application in the field of supercomputers.
“In the middle of the night, such a program could mobilize hundreds of machines in one building,” he wrote later. Before morning, as users arrived to reclaim their machines, the worm would retreat. After hibernating in a machine or two during the day, it would reemerge the next evening--an image that led one of Shoch’s colleagues to liken it less to a worm than to a vampire.
Shoch eventually was able to invest his worm with the ability to seek out idle Altos, boot up a host machine through the network and replicate by sending copies of itself from machine to machine, remainNing in communication with its dispersed offspring.
But he was also well aware that a program capable of commandeering idle computers in their owners’ absence would have to be stringently controlled. It was, for example, forbidden to access any Alto’s disk drive--a necessary precaution lest it inadvertently overwrite someone’s work, which he knew would be viewed as “a profoundly antisocial act.”
Nevertheless, one night something unexpectedly went wrong. Shoch and two colleagues had set a small worm loose in the PARC Ethernet to test a control function. Confident that their program was suitably innocuous, they left it running and went home.
At some point--they never figured out exactly when and why--the program became corrupted so badly it crashed its host computer. Sensing it had lost a segment, the control worm sent out a tendril to another idle Alto. That host crashed, and the next, and the next. For hours the silent carnage spread through the building until scores of machines were disabled.
Then morning came, and dozens of PARC researchers arrived for work to discover their machines had crashed. At first this did not cause any alarm--in those early years Altos frequently crashed for no reason. But soon it became obvious that this was no random occurrence. For one thing, whenever anyone stepped away from an Alto for even a few minutes, it crashed again, seized by the still-insatiable worm.
Summoned to the lab, Shoch and his colleagues began pursuing the program through the network like exterminators chasing rats through a sewer. Eventually they had no choice but to eradicate it with a sort of software bomb--a self-destruct command Shoch had preloaded as insurance against some unpredictable disaster.
To his relief, all worm activity ceased. That was the good news. The bad news was that the entire PARC Ethernet had been figuratively reduced to a smoking ruin. Scattered around the building were 100 dead Altos. “The embarrassing results,” he said, “were left for all to see.”
Yet it is a lesson to computer and network designers today that rather than treating the worm as a menace, PARC learned from its experience and continued to develop the concept of a roving, self-executing program.
Soon there were dozens of new applications. The Billboard worm snaked through the system depositing a “cartoon of the day” on every machine to greet workers each morning. The Alarm Clock worm maintained a table of wake-up call requests, and at the pertinent time placed a call to the user’s phone. The Peeker checked every Alto’s memory banks at night and notified technicians of which machines might need a new chip.
The principle survives today--”spiders,” “bots” and all sorts of other programs designed to rove the Internet, collecting information on behalf of their users.
That is the upside of the technologies that infect us with viruses. Whether they’re innocuous like Melissa or frighteningly destructive, they still point us toward the ever-expanding capabilities of the network to improve our lives.
Times staff writer Michael Hiltzik is author of the new book “Dealers of Lightning: Xerox PARC and the Dawn of the Computer Age.” He can be reached via e-mail at michael.hiltzik@latimes.com.
