What is IDS and IPS?
An IDS detects suspicious traffic and raises an alert. An IPS sits in the path and can block it.
In plain English
Both look for known attack patterns or unusual behaviour. An intrusion detection system watches a copy of the traffic and tells people. An intrusion prevention system sits in line with the traffic, so it can drop the bad packets as they pass. The trade-off is that an in-line device can also block good traffic by mistake.
Example
If a device only logs an alert about a port scan, it is acting as an IDS. If it automatically drops the scanning traffic, it is acting as an IPS.
Where you will meet it
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Related terms
- Zero trust: A security approach that never assumes a request is safe just because it comes from inside the network.
- CIA triad: Three goals of information security: confidentiality, integrity and availability.
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