Byteman Blows the Whistle on the Sysop Cops : THE CUCKOO’S EGG Tracking a Spy Through the Maze of Computer Espionage<i> by Clifford Stoll(Doubleday: $18.95; 336 pp.; 0-385-24946-2) </i>

Although trained as an astronomer and software writer, Cliff Stoll was working as a computer- system operator at the Berkeley Livermore Laboratory in late 1986 when he got involved in an attempt to catch a computer hacker. An accounting error of 75 cents led him to discover that someone was networking into the lab’s system and using it in odd ways. The hacker--wherever he was--was both reading files from his computer and using it as a conduit to break into other, primarily military, installations.

Stoll became more and more interested in the hacker and eventually set up a homemade system for watching and keeping a log describing each time he connected with the Berkeley computer. By keeping detailed records, he began to create a profile of the hacker: amazingly patient; kept notes or had an excellent memory; fairly competent at scooting around the maze of networks throughout the United States; good working knowledge of chronic weak points in both Vax and Unix systems.

Stoll’s efforts to trace the hacker met with frustration, and several times he was forced to decide whether to give it up or go ahead. As he tells the story, Luis Alvarez, Nobel Laureate, happened along with just the advice that he needed--to treat it not as a task with a single goal but as open-ended research. By investigating the break-ins and not worrying too much about the outcome, he would at least learn about computer networks and security. Whether he caught the malefactor or not, he would expand his own knowledge.

What unfolds is interesting in precisely those terms--as an inquiry into the insecurity of computer systems. As the author readily admits, it is not so interesting vis-a-vis the further dirty tricks of the hacker, which are distinguished only by persistence. Stoll reaches the conclusion that breaking into and exploiting a great number of networked computers requires only a modest degree of knowledge. The same half-dozen tricks work again and again. Rather than wizardry, it is a craft commensurate with, say, a working knowledge of heisting cars. Of the 430 computers that the hacker eventually attacks, he repeatedly makes it into at least 30 of them, sifting through them for information on such things as the Strategic Defense Initiative and the design of radar systems.

Reporting the matter to the authorities, Stoll learns that none of the “three-letter agencies” (FBI, CIA, NSA) acts terribly interested in the problem. When he tells them that computers at missile-testing facilities, the Pentagon or the Lawrence Livermore Lab are being rifled, they act as worried as if they’d been told someone was reading the magazines in the waiting room. If the systems are not classified--as none was--no one appears too worked up about it.

He informs them that the hacker is assuming system control in military and research computers as a method of entry, altering files for future re-entry and reading a ton of material, and they yawn. They do pat him on the back, tell him to keep up the good work and cooperate with his efforts to trace and log the hacker, but it hardly becomes a red alert.

Stoll begins to think that not only are most of the doors unlocked but there aren’t any cops in town. Meanwhile, he is doing little of his regular work at the lab, and his boss and others are getting impatient with his apparent obsession.

The story lies not in the hacker’s brilliance--Stoll often comments on how repetitious and “boring” his methods are--but in the search itself, the author’s continuing efforts to keep the three-letter agencies interested and the personal changes that he undergoes.

The saga is intriguing, yet the reader may grow impatient with some of it. It is written as if from his logbook, and not enough effort is made to get beyond this information--to frame, interpret or summarize from the enlarged perspective of later knowledge, or further information. Since the hacker’s dirty tricks are so repetitious, the author could have summarized more; and, since the changes that the agencies go through are frequent and unexplained, from interest to disinterest and back again, he might have condensed and tried to interpret their behavior. Finally, the outcome of the search is explained not with any basic research by the author but with information from a single popular magazine article.

In his attempt to dramatize the events, Stoll portrays himself as a gee-whiz whiz kid--the innocent, granola-eating, blue jeans-clad, bashful, yet brilliant “typical Berkeleyite.” We are treated to a great deal of information regarding his domestic life and love affair; his wife-to-be is sweet, brilliant and strong, and he cannot restrain himself from lacing the account with vignettes of their perfect Northern California relationship. One does not have to doubt the spin that he regularly puts on such events to grow weary of them.

Indeed, Stoll’s self-image plays a large role in the book, as the brilliant “old hippie” (he is 30 years old) faces off against the incompetent bureaucrats, in the process changing from someone with de rigueur anarchistic leanings into a one-man avenger of computer crime, far tougher than the foolish FBI. He seems to assume that dozens of agents should spring into overdrive at his command; when that doesn’t happen, he describes them as time-servers, and himself as Byteman, avenger of electronic wrong.

In short, I am suspicious of both sides of Stoll’s self-image--both the hapless “old hippie” and the born-again computer hard-liner who would like to chop the digits off those malicious hackers.

A very good thing about this book, however, is that it was written by an actual system operator. There is lots of popular writing concerning various computer fields, but little by the “sysops,” the people who actually are responsible for the system. His descriptions of break-ins and chronic weaknesses are detailed and reliable. And his point of view, finally--the severity with which he would treat hackers and computer criminals--is more understandable, considering the fact that he was in charge of keeping the boxes humming.