Ethernet networks use a Media Access Control (MAC) address to identify and communicate with each Ethernet-based device on the network. MAC addresses are 48 bits in length. The first 24 bits represent the manufacturer of the device. The final 24 bits are a number assigned by the manufacturer so that every Ethernet device produced has a globally unique hardware MAC address. There are some cases where the MAC address of one device needs to match the address of another. You can change your MAC address on a router running DD-WRT through the administrative interface.
Open a Web browser and then type the IP address of the router into the address bar. For example, type "192.168.0.1" and then press "Enter."
Click the "Setup" tab. Enter the router's user name and password, if prompted.
Click "MAC Address Clone."
Click "Enable" and then enter the desired MAC address into the "WAN" or "Wireless" field to change the MAC address of each device, respectively.
Click "Apply Settings" to save the changes.