Microsoft has 3,700 access points deployed worldwide for their enterprises, and finds that managing them is a bear: Of course, they're using Cisco APs, but they're not using Cisco's WLSE for controlling the configuration of hundreds of APs at once. Cisco's own network of 3,000 APs is segregated into virtual LANs per building for ease of roaming because their technology doesn't allow policy-level management control across aggregations of APs only (obviously) across switches.