NIDS

NIDS can refer to:National Institute for Discovery ScienceNetwork intrusion detection system
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A network intrusion detection system (NIDS) is an intrusion detection system that tries to detect malicious activity such as denial of service attacks, port scans or even attempts to crack into computers by monitoring network traffic.The NIDS does this by reading all the incoming packets and trying to find suspicious patterns. If, for example, a large number of TCP connection requests to a very large number of different ports are observed, one could assume that there is someone committing a "port scan" at some of the computer(s) in the network. It also (mostly) tries to detect incoming shellcodes in the same manner that an ordinary intrusion detection systems does.
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n. nest, structure in which a bird lays eggs and cares for its young

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