"The first generation of viruses were simple in their approach. The designers correctly assumed that no one was looking for them, and they could enter systems without any deterrence. They erase files, scramble data, re-format hard drives . . .make the comput- er data useless. "Then the second generation of viruses came along with the nom-de-guerre stealth. These viruses hid themselves more elabo- rately to avoid detection and had a built in self-preservation instinct. If the virus thinks it's being probed, it self de- structs or hides itself even further. "In addition, second generation viruses learned how to become targeted. Some viruses have been designed to only attack a competitor's product and nothing else." "Is that possible?" Asked Nancy Deere. "It's been done many times. Some software bugs in popular soft- ware are the result of viral infections, others may be genuine bugs. Imagine a virus who sole purpose is to attack Lotus 123 spreadsheets. The virus is designed to create computational errors in the program's spreadsheets. The user then thinks that Lotus is to blame and so he buys another product. Yes, ma'am, it is possible, and occurs every day of the week. Keeping up with it is the trick. "Other viruses attack on Friday the 13th. only, some attack only at a specified time . . .the damage to be done is only limited by imagination of the programmers. Third generation viruses were even more sophisticated. They were designed to do damage not only to the data, but to the computer hardware itself. Some were designed to overload communications ports with tight logical loops. Others were designed to destroy the hard disk by directly overdriving the disk or would cause amonitor to self-destruct. There is no limit to the possibilities. "You sound as though you hold their skills in high regard, Doc- tor." Rickfield continued to make snide remarks whenever possi- ble. "Yessir, I do. Many of them have extraordinary skills, that are unfortunately misguided. They are a new breed of bored criminal." "You mentioned earlier Doctor, that there were over 5000 known viruses. How fast is the epidemic, as you put it, spreading?" Senator Nancy Deere asked while making prolific notes throughout. "For all intents and purposes Senator, they spread unchecked. There is a certain amount of awareness of the problem, but it is only superficial. The current viral defenses include signature identification, cyclic redundancy checks and intercept verifica- tion, but the new viruses can combat those as a matter of rule. If the current rate of viral infection continues, it will be a safe bet that nearly every computer in the country will be in- fected ten times over within three years."