Patent ID: 7958541

Claim:
A method for preventing Media Access Control (MAC) address counterfeiting, comprising: receiving, at an access device, an authentication request carrying a first source MAC address from an access port provided by the access device, wherein the authentication request is sent by a user device to the access device via the access port; after receiving the authentication request, storing, at the access device, a relationship between the first source MAC address and the first access port information of the access port, and sending the first source MAC address and first access port information of the access port from the access device to an authentication device; receiving, at the authentication device, the first source MAC address and the first access port information of the access port, wherein the first source MAC address and the first access port information are associated with the authentication request from the access port; determining, at the authentication device, whether the first source MAC address received is a counterfeit MAC address by detecting whether the first source MAC address received is consistent with a second source MAC address that is stored in the authentication device and the first access port information received is consistent with second access port information that is stored in the authentication device, wherein the second access port information is bound with the second source MAC address; and if the first source MAC address received is a counterfeit MAC address, rejecting, by the authentication device, the authentication request by sending an authentication failure message including the first access port information from the authentication device to the access device; in response to the authentication failure message, deleting the relationship between the first source MAC address and the first access port information of the access port at the access device.