Not all the autonomous Cisco IOS Software-based AP models can be converted. These are the models that you can convert to Lightweight AP Protocol (LWAPP) mode:
*
All Cisco Aironet 1130 AG APs
*
All Aironet 1240 AG APs
*
For all Cisco IOS Software-based Aironet 1200 Series modular AP (1200/1220 Cisco IOS Software upgrade, 1210, and 1230 AP) platforms, the ability to convert the AP depends on the radio.
o
If the radio is IEEE 802.11g, MP21G and MP31G are supported.
o
If the radio is IEEE 802.11a, RM21A and RM22A are supported.
You can upgrade the 1200 Series APs with any combination of supported radios:
o
G only
o
A only
o
Both G and A
Note: An autonomous AP must run Cisco IOS Software Release 12.3(7)JA or later before you can convert it to LWAPP.
Note: Only the Cisco 4400 and 2006 wireless LAN controllers (WLCs) support autonomous APs that have been converted to lightweight mode. Cisco WLCs must run a minimum software version of 3.1. The Cisco Wireless Control System (WCS) must run a minimum version of 3.1. The upgrade utility is supported on the Microsoft Windows 2000 and Windows XP platforms.
Refer to Upgrading Autonomous Cisco Aironet Access Points to Lightweight Mode for details on how to perform the conversion.
http://www.cisco.com/en/US/products/hw/wireless/ps430/products_qanda_item09186a00806a4da3.shtml