MPSK (Multi Pre-Shared Key) is a feature that allows assigning different pre-shared keys (PSKs) to different devices or groups of devices on the same WLAN. MPSK improves security over WPA2 in personal mode, which uses a single PSK for all devices on the WLAN. With MPSK, you can create and manage multiple PSKs, each with its own role, policy, and expiration date. You can also revoke or change a PSK for a specific device or group without affecting other devices on the WLAN. MPSK is compatible with devices that support WPA2 in personal mode only, as they do not need to support any additional protocols or certificates.

To use MPSK on the WLAN to which the devices connect, you need to enable MPSK in the WLAN settings and configure the PSKs in Aruba ClearPass Policy Manager (CPPM). You can find more information about how to configure MPSK in the [Configuring Multi Pre-Shared Key - Aruba] page and the [ClearPass Policy Manager User Guide] . The other options are not correct because they either do not improve security or are not applicable for devices that support WPA2 in personal mode only. For example, configuring WIDS policies that apply extra monitoring to these particular devices would not prevent them from being compromised or spoofed, but rather detect and mitigate potential attacks. Connecting these devices to the same WLAN to which 802.1X-capable clients connect, using MAC-Auth fallback, would not provide strong authentication or encryption, as MAC addresses can be easily spoofed or captured. Enabling dynamic authorization (RFC 3576) in the AAA profile for the devices would not affect the authentication process, but rather allow CPPM to change the attributes or status of a user session on the controller without requiring re-authentication.