Cisco-proprietary Aironet extensions detect the capabilities of Cisco Aironet client devices and support features that require specific interaction between the Cisco Access Point (AP) and associated client devices. Non-Cisco clients do not always support the Aironet extensions.
If disassociation of non-Cisco clients and Cisco APs is observed, disable Aironet extensions and set the preamble to long. A long preamble ensures compatibility between the Cisco AP and all early models of Cisco Aironet Wireless LAN Adapters (PC4800 and PC4800A). If these client devices do not associate to the AP, enable short preambles.