While intrusion detection systems (IDS) monitor the network and send alerts to network administrators about potential threats, intrusion prevention systems take more substantial actions to control access to the network, monitor intrusion data, and prevent attacks from developing.

IPS evolved from IDS. IDS technology uses the same concept of identifying traffic and some of the similar techniques with the major difference being that IPS are deployed in-line and IDS are deployed off-line or on tap where they still inspect a copy of the entire traffic or flow but cannot take any preventive action. IDS are deployed to only monitor and provide analytics and visibility into the threats on the network.

Historically, IPS only reacted to cyber breaches, but this reactive stance is no longer satisfactory. IPS is now part of full network security suites, including threat monitoring, firewalls, intrusion detection, anti-virus, anti-malware, ransomware prevention, spam detection, and security analytics.

Recent trends in IPS include using AI to automate the detection process. The future of IPS technology extends network perimeter security with a multi-layered defense. Cloud IPS services perform this security function using extended detection, response, and endpoint protection.

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What is an Intrusion Prevention System? Definition ... - Fortinet