Types of MAC Addresses Krish Advani 17/05/2013 Engineering Two basic forms of MAC which are used in most of today´s LAN are: Token passing method used by the token ring and FDDI. CSMA/CD carrier sense multiple access with collision detection. Token passing method: In this method, a special frame called token is passed from one workstation to the other. Only the system which possess this token is allowed to transmit its data on the network. A workstation, after transmitting its data will release the token to the next workstation. This method is used by the token ring and FDDI systems. CSMA/CD: The long form of CSMA/CD is carrier sense multiple access with collision detection. In this method when a workstation has to send some data, it listens to the network cable and if it is idle then sends the data. On CSMA/CD network the workstation can transmit simultaneously which results in packet collision. So this system has a collision detection mechanism. When a collision is detected, the corresponding data is retransmitted.