Access control method and system, and access point

The present invention provides an access control method and system, and an access point. When a fault occurs in an AC, an AP configures a network-layer interface of the AP according to an IP address and a MAC address of the AC that are obtained by means of pre-learning, and then the 5 AP routes a received packet to a Web server on a WLAN by using the configured network-layer interface, where the packet is used by a first STA to request to access an external server. Therefore, interconnection and interworking among wireless local area networks are implemented, and a breakdown of a wireless local area network caused in a centralized network architecture due to occurrence of a fault in an AC is avoided. A first STA is connected to an AP 201 When the first STA accesses an external server, the AP listens to a packet of the first STA, and obtains an IP address and a MAC 202 address of an AC by means of learning After determining that a fault occurs in the AC, the AP configures a network-layer interface of the AP according to the 203 IP address and the MAC address of the AC that are obtained by means of pre-learning, and constructs an address pool The AP receives, by using the configured network-layer 204 interface, an http request packet sent by the first STA The AP redirects, according to an external routing entry, the http request packet to a URL for the content page that is 205 temporarily stored on a Web server A second STA is connected to the AP 206 The AP acquires an authorized user list from the AC when the 207 fault in the AC is cleared The AP removes the association with the second STA if the 208 second STA is not in the authorized user list