What Does Network-based Intrusion Detection System (NIDS) Mean?
A network-based intrusion detection system (NIDS) is used to monitor and analyze network traffic to protect a system from network-based threats.
A NIDS reads all inbound packets and searches for any suspicious patterns. When threats are discovered, based on its severity, the system can take action such as notifying administrators, or barring the source IP address from accessing the network.
Techopedia Explains Network-based Intrusion Detection System (NIDS)
Intrusion detection systems (IDSs) are available in different types; the two main types are the host-based intrusion system (HBIS) and network-based intrusion system (NBIS). Additionally, there are IDSs that also detect movements by searching for particular signatures of well-known threats.
An IDS compliments, or is part of, a larger security system that also contains firewalls, anti-virus software, etc. A NIDS tries to detect malicious activity such as denial-of-service attacks, port scans and attacks by monitoring the network traffic.