My AIR-LAP1252G-E-K9 access point doesn't register against the controller. The switch is seeing both the MAC and the IP of the AP, but the power inline seems not to be enough. Although the switch sees the AP's IP address by CDP, this one doesn't answer the ping request.
Powering the Aironet 1250 Series Access Point with 802.3af Power over Ethernet
The Aironet 1250 Series Access Point with one RM1252 radio module installed requires 12.95W, which is within the 802.3af Power over Ethernet (PoE) standard. Any Cisco switch supporting 802.3af may be used to power the Aironet 1250 Series Access Point with one RM1252 radio module installed. This is ideal for businesses that chose to only deploy on a single frequency (2.4 GHz or 5 GHz). A single radio provides optimum performance with approximately 300 Mbps maximum PHY data rate. Customers who deploy dual-band, 802.11n radios and power the 1250 Series using standard 802.3af will have more reliable and predictable coverage than that provided by traditional 802.11a/g networks; however, operation will be limited to a single transmitter per radio with maximum PHY data rates of 150 Mbps instead of 300 Mbps per radio. Customers with a significant investment in 802.11 a/b/g client devices that have low-to-medium bandwidth needs but high-reliability requirements will benefit the most from this type of deployment scenario.
Powering the Aironet 1250 Series Access Point with Cisco Enhanced PoE
Cisco Enhanced PoE was designed for customers who want to install new PoE-enabled technologies that require greater than 15.4W per port to function at full capability, such as wireless technology based on the IEEE 802.11n standard. Cisco Enhanced PoE provides the full power requirements for dual-radio modules and eliminates the need to run an additional cabling drop or insert a separate power injector. Support for Enhanced PoE is currently available on a variety of Cisco CatalystÂ® switching platforms. For more information on Enhanced PoE, visit