A token ring is a ring network that constantly sends a small message, or token, around the network. Tokens are constantly present on the network medium so when a computer wants to send a message, it takes a token.
Developed by IBM, Token Ring offers a method to connect devices in a LAN (local area network). Hence, Token Ring offers the same service as Ethernet, implemented in a different manner: an electronic token (a data packet) is passed around stations in a ring. Most small businesses install Ethernet networks, due to their comparative simplicity to Token Ring. Token Ring networks take on the physical appearance of a star, but actually operate as a logical ring. A device (such as a PC) takes possession of the token, transmits its data, then frees the token after the data has made a complete circuit of the electrical ring. The IEEE 802.5 standard specifies the wiring on which Token Ring operates (STP, UTP or fiber-optic cable); Token Ring operates at either 4 or 16Mbps. Also see Ethernet Fibre Optic Cable IEEE LAN Mbps Network Packet PC STP UTP