Intrusion Detection System (IDS) are a necessary part of any strategy for enterprise security. What are Intrusion Detection Systems? CERIAS, The Center for Education and Research in Information Assurance and Security, defines it thus:
“The purpose of an intrusion detection system (or IDS) is to detect unauthorized access or misuse of a computer system. Intrusion detection systems are like the anti-theft alarms for computers. They sound alarms and sometimes even take corrective action when an intruder or abuser is detected. Many intrusion detection systems have been developed but the detection schemes generally fall into one of two categories, detection anomaly or misuse detection. detectors to search for abnormalities in behavior that deviates from normal system use. Misuse detectors look for behavior that matches a known attack scenario. A lot of time and money ‘ efforts have been invested in intrusion detection, and this list provides links to many sites that deal with some of these efforts “(http://www.cerias.purdue.edu/about/history/coast_resources / intrusion_detection / )
There is a sub-category of intrusion detection systems called systems intrusion detection system (NIDS). These systems control packets on the network and son looking for suspicious activity. Network intrusion detection systems can control multiple computers at once on a network, while other intrusion detection systems may only monitor alone.