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If your computer crashes, think of these two

Three decades ago, alum Fred Cohen coined a famous term in computer science

by Arash Zandi

Computer problems can cause a lot of stress, especially when valuable data, photos, music or memories are deleted from our devices. Three decades ago these malicious defects didn’t have a name. A USC Viterbi graduate student and his professor gave them one.

Not all viruses are bad, according to USC alum Fred Cohen. (Photo/courtesy of free images.com)

Not all viruses are bad, according to USC alum Fred Cohen. (Photo/courtesy of free images.com)

The year was 1983. USC Viterbi School of Engineering student Fred Cohen PhD ’86 was in a class taught by computer science Professor Leonard Adleman, who was talking about a malicious program in a timesharing system at UCLA.

Once [Leonard] Adleman came up with the name, I started working on it and writing on it.

Fred Cohen

“All of a sudden, the proverbial light came up above my head like in a cartoon, an ‘aha’ moment,” Cohen said.

He realized that when a program placed a copy of itself into other programs, it would spread like a disease. Cohen shared his observation with Adleman, who suggested that he call it a computer virus.

“Once Adleman came up with the name, I started working on it and writing on it,” Cohen said.

Once he had the name, Cohen wanted to see a virus in practice to test his theory on how it spread. He conducted a test on one of the computers he oversaw as a systems administrator to see how fast it would spread. Then he started trying to find defenses for it — a line of work he continued until 1992.

Cohen has written more than 50 professional publications and 11 books. He won the Techno-Security Industry Professional of the Year Award in 2002 and is now one of the world’s most trusted individuals in the information protection field.
He provides research and advisory services for the U.S. government and leading firms across all industries.

“The first virus scanner, if you want to call it that, was something that I wrote which looked for copies of my viruses on my computer,” he said. “I understood that it would not be an effective defense because I could just keep writing more viruses and could guarantee that the scanner would always produce an unlimited number of false positives, false negatives or run forever.”

But Cohen emphasized that not all viruses are bad, as he believes in the existence of “benevolent viruses.” The concept may sound contradictory, but Cohen said it’s not.

An example of a benevolent virus would be maintenance viruses that simply automate the work that systems administrators would otherwise do manually, such as deleting old files, clearing up disk space and checking for errors.

Cohen wrote a paper on them in 1991.

“In the case of computer viruses, we have not adequately considered the potential for beneficial uses. … Perhaps we will even learn something about ourselves and our environment through this effort, and perhaps we will not, but I don’t think we can afford to ignore the implications,” Cohen wrote.

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