1. Network Intrusion Detection System (NIDS): A NIDS is a system that monitors network traffic for suspicious activity and alerts the network administrator of any malicious activity. An example of a NIDS is Snort.
2. Host Intrusion Detection System (HIDS): A HIDS is a system that monitors the activities of a single host for suspicious activity and alerts the system administrator of any malicious activity. An example of a HIDS is OSSEC.
3. Signature-Based Detection: Signature-based detection is a type of IDS that looks for known malicious patterns in network traffic. It compares the network traffic against a database of known malicious patterns and alerts the network administrator if a match is found. An example of a signature-based IDS is Snort.
4. Anomaly-Based Detection: Anomaly-based detection is a type of IDS that looks for suspicious activity that is outside of the normal network traffic patterns. It compares the network traffic against a baseline of normal network traffic and alerts the network administrator if any suspicious activity is detected. An example of an anomaly-based IDS is Suricata.
5. Protocol Analysis: Protocol analysis is a type of IDS that looks for malicious activity in the data that is sent over the network. It looks for malicious patterns in the data and alerts the network administrator if any suspicious activity is detected. An example of a protocol analysis IDS is Bro.