token ring network

Definition

High speed, single channel, baseband local area network (LAN) architecture which eliminates the pervasive network problem of data-collision by using a data packet (called 'token') of control message. Although tens of thousands of tokens are generated every second by a designated computer (called token manager) in the network, there is only one token present in the network at any one point in time which passes from one device or computer (called node) to the next in one direction only. Since a source node must use a token to send data, it captures the circulating token, attaches to it the message and the address of the destination node, and passes it on to the next downstream node. As the token travels through the network, each node reads its destination address and acts accordingly. When the token reaches its destination, that node copies the message and sends the token downstream to the token manager which regenerates (resets) the token and the cycle starts again. Invented by IBM, token ring architecture can connect all types of computers through a wiring scheme that resembles a ring or a star (or a hybrid of both) at speeds higher than 16 million bits per second (Mbps) over shielded twisted-pair wire. See also Ethernet.