MPSK Local is a feature that can reduce the IT administration overhead associated with deploying devices that do not support 802.1X authentication while maintaining a secure environment. MPSK Local allows the switch to automatically generate and assign unique pre-shared keys for devices based on their MAC addresses, without requiring any configuration on the devices or an external authentication server. The other options are incorrect because they either require manual intervention by the installers or the MPSK gateway, or they do not provide unique pre-shared keys for devices. Reference: https://www.arubanetworks.com/techdocs/AOS-CX_10_08/UG/bk01-ch05.html https://www.arubanetworks.com/techdocs/AOS-CX_10_08/UG/bk01-ch06.html