A ring topology is a single closed ring

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A ring topology is a single closed ring containing nodes and links, with each

A ring topology is a single closed ring containing nodes and links, with each node connecting to only the two adjacent nodes.

The Token Ring topology was originally developed by IBM in the 1970 s. It

The Token Ring topology was originally developed by IBM in the 1970 s. It is still IBM's primary LAN technology and is second only to Ethernet/IEEE 802. 3 in general LAN popularity. The related IEEE 802. 5 specification is nearly identical to and completely compatible with IBM's Token Ring network. In fact, the IEEE 802. 5 specification was modeled after IBM’s Token Ring, and it continues to shadow the IBM Token Ring development. The term Token Ring is generally used to refer back to both IBM's Token Ring network and IEEE 802. 5 networks.

When a Token Ring network starts up, all machines take part in a negotiation

When a Token Ring network starts up, all machines take part in a negotiation to decide who will control the ring, or become the 'Active Monitor' to give it all control. This is won by the machine with the highest MAC address who is participating in the contention procedure, and all other machines become 'Standby Monitors'. The job of the Active Monitor is to make sure that none of the machines are causing problems or defective on the network, and to re-boot the ring after a break or an error has occurred. The Active Monitor performs ring purges when there appears to be a problem and Ring Polling every seven seconds. The ring polling allows all machines on the network to find out who is participating in the ring and to learn the address of their Nearest Active Upstream Neighbour (NAUN).

The cabling typically used for Token Ring LANs is either STP or UTP cables.

The cabling typically used for Token Ring LANs is either STP or UTP cables. The standard recommends the use of either STP Type 1 A cable or UTP Cat 5 cable. Two pairs of twisted wires are used. One used for receiving data, the other used for transmitting data. It is only recommended to run at max lobe length for UTP when using a passive concentrator, 100 meters. This length can be doubled when using an active re-timing concentrator. An active concentrator has a repeater unit at every lobe port and performs the same function of timing recovery and re-transmission as the physical layer of the NIC (station).

http: //www. cisco. com/univercd/cc/td/doc/cisintwk/ito_doc/toke nrng. htm http: //www. rad. com/networks/1997/nettut/token_ring. html http: //www. iol.

http: //www. cisco. com/univercd/cc/td/doc/cisintwk/ito_doc/toke nrng. htm http: //www. rad. com/networks/1997/nettut/token_ring. html http: //www. iol. unh. edu/training/tokenring/vjs_thesis/vjthes 9. ht ml by: Craig Messenger