Access control method and authentication device

The embodiments of the invention provide an access control method and an authentication device. The invention aims to perform dynamic access control on the IP address of a terminal. According to the embodiments of the invention, the method comprises the following steps that: the authentication device obtains the medium access control (MAC) address and current Internet protocol (IP) address of the terminal; the authentication device sends an authentication request to a server, wherein the authentication request includes the MAC address and the current IP address of the terminal; the authentication device receives an authentication response message sent by the server, wherein the authentication response message includes an access control policy corresponding to the MAC address and current IP address of the terminal; and the authentication device performs access control on the current IP address of the terminal according to the access control policy. With the access control method and the authentication device o