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Intrusion Detection System (IDS)

Definition

A network or host-based monitoring system that analyses traffic or system behaviour against a rule set (signature-based) or a statistical baseline (anomaly-based) and generates alerts on matches. A network IDS (NIDS) such as Snort or Suricata sits on a span or tap port; a host IDS (HIDS) runs on individual endpoints.

Related terms

DHCP lease log
A record maintained by a Dynamic Host Configuration Protocol server that maps each IP address assignment to the requesting device's MAC address,...
NetFlow
A network protocol (originally Cisco, now standardised as IPFIX under RFC 7011) that records metadata about IP traffic flows: source and destination...
PCAP (packet capture)
A file format (and the process of creating it) that records every byte of every network packet passing a capture point, including...
RADIUS log
An authentication, authorisation, and accounting record produced by a Remote Authentication Dial-In User Service server. Each entry records the username, authenticating device...
Syslog
A standardised protocol (RFC 5424) for transmitting log messages from network devices to a centralised log server. Routers, switches, firewalls, and servers...

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