Token Ring

The use of token ring LANs was popularized by IBM in the mid 1980s when it released its IBM token ring architecture. Physically, a token ring network is wired as a star, with 'hubs' and arms out to each station and the loop going out-and-back through each.

The IEEE ratified the Token ring LAN speeds of 4 Mbit/s and 16 Mbit/s in the IEEE 802.5 standard.

The original Token Ring specifications called for shielded twisted-pair (STP) cable using either a DB9 connector or a unique square connector called the IBM data connector. Later, Token Ring was adapted to use conventional unshielded twisted-pair (UTP) cable with RJ-45 connectors. The most common kinds of Token Ring cabling in use to day are Type 1 and Type 6 STP as well as Type 3 UTP.

Type 1 shielded twisted-pair (STP) cable is the original wiring for Token Ring. In Type 1 cabling, each wire is constructed of 22 AWG solid copper. Type 1 cable is not as flexible as Type 6 cable and is generally used for long runs in areas where twists and turns are less likely, such as in walls or conduits.

Type 6 Token Ring cable is a lighter, more pliable version of Type 1 cable. It’s constructed of two stranded 26 AWG copper pairs that are surrounded by an overall braided shield. Type 6 cable is commonly used in offices and open areas, and its flexible construction enables it to negotiate multiple twists and turns.

Type 3 or UTP Token Ring cabling uses the same twisted-pair CAT3, CAT5, or CAT5e cabling with RJ-45 connectors as 10BASE-T Ethernet does. Attaching older Type 1 Token Ring to UTP Token Ring requires a balun or adapter.

With the development of switched Ethernet and faster variants of Ethernet, the token ring networks have since declined in usage and the standards activity has since come to a standstill as 100Mbps switched Ethernet has dominated the LAN/layer 2 networking market.

Learn more: Standard en ThinNet Ethernet