Next February, the Pentagon will award dozens of contracts for 14 separate programs involving Cyber Defense, seeking ways to defend computer networks from hackers (including those backed by unfriendly foreign governments). Two general categories of cyber defenses are being studied. Intelligence Software Agents track users inside a system and what kinds of files they access. If a given user starts accessing a different kind of file, or a kind of file he is not involved in, or a kind of file he is not authorized to use, it sounds the alarm. Humans could intervene and decide whether to kick the violator out of the system or try to track it back to the source. Neural Networks recognize patterns of activity, and look for new patterns. Rather than simply sounding an alarm, the Neural Network system can trigger network management systems that could block off parts of the network or stop certain types of new information from entering the network. -Stephen V Cole