According to the Designing Aruba Solutions course, dedicated Air Monitors (AMs) are APs that are configured to scan all channels for wireless threats and perform wireless intrusion prevention system (WIPS) functions. One of the advantages of using dedicated AMs over APs that are doing WIPS in AP mode (hybrid) is that AMs can implement wireless containment on any channel on which they detect a threat without affecting the service of legitimate clients. Wireless containment is a technique that prevents rogue APs or clients from communicating with the network by sending deauthentication or disassociation frames to them. However, if an AP that is serving clients performs wireless containment on a different channel, it will have to switch channels frequently, which will degrade the performance and user experience of the clients. Therefore, dedicated AMs are recommended for customers who need effective and efficient wireless containment without compromising client service.

References:

Designing Aruba Solutions, Rev. 20.11, Module 5: Aruba Security Design, page 5-13

Aruba Validated Reference Design: Wireless Intrusion Prevention System, page 10