Rapid authentication method, access controller and system for wireless local area network

The present invention relates to a rapid authentication method, an access controller (AC) and a system for a wireless local area network (WLAN). The method includes: after a terminal is attached to a network, an AC querying the media access control (MAC) address of the terminal and binding information about user agent (UA) and account information toward a local authentication, authorization and accounting (AAA) server; and performing portal authentication on the terminal and a central AAA server according to the MAC address and the binding information about the UA and account information. The present invention reserves the portal authentication flow of the existing central AAA server, adds a secondary local AAA used for the authentication of the MAC address and UA of a WLAN terminal, proposes to use the commonly supported terminal MAC address and UA as interaction information for authentication, and at the same time performing identity information check through short messages can be adapted for all WLAN terminals, which is compatible with the existing webpage authentication manner and can be realized by only slightly reforming the network and authentication system, thus it is convenient for the user to rapidly access the network, greatly reducing the user operation complexity of terminals such as mobile phones, and the user experience can be improved effectively.