Patent ID: 8842830

Claim:
A method for sending a key on a Wireless Local Area Network (WLAN) in which an Access Controller (AC) is separated from a broadband remote access server (BRAS), the method comprising: receiving, by the BRAS, a first Control and Provisioning of Wireless Access Point (CAPWAP) message sent by the AC, wherein the first CAPWAP message carries an Internet Protocol (IP) address of an Access Point (AP), an IP address of the AC, and a media access control (MAC) address of a WLAN station; obtaining, by the BRAS, the IP address of the AP, the IP address of the AC, and the MAC address of the WLAN station from the first CAPWAP message, and storing the IP address of the AP, the IP address of the AC, and the MAC address of the WLAN station in a station information table; sending, by the BRAS, a second CAPWAP message to the AC to trigger the AC to send association success information to the WLAN station, wherein the second CAPWAP message carries the MAC address of the WLAN station; receiving, by the BRAS, an authentication request message of the WLAN station forwarded from the AC, and initiating authentication to an Authentication, Authorization and Accounting (AAA) server; when receiving a master key of the WLAN station sent from the AAA server, searching, by the BRAS, the station information table for an IP address of an AC associated with the WLAN station; and sending, by the BRAS, a third CAPWAP message to the AC to instruct the AC to perform a 4-way handshake with the WLAN station to agree on a transient key, wherein the third CAPWAP message carries the master key of the WLAN station, a 4-way handshake triggering bit, and the MAC address of the WLAN station.