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In t r u s I o n De t e c t I o n
Network intrusion detection systems (NIDS) monitor events on a
network and analyze them to determine if they indicate an incident.
If it is determined that there is an incident, an alert may be raised.
Network intrusion prevention systems (NIPS) are essentially the
same animal except that they will also block the potentially malicious
network activities. NIPS, as a packaged commercial product, came
after NIDS, although it should be said that even some of the earliest
open-source NIDS software packages could be congured to send a
TCP layer Reset packet to shut down the potentially malicious trans-
action in progress.
ere are glitzy well-marketed products available today that per-
form any kind of intrusio ...