Token Ring topology
This topology is based on the topology of the “physical ring connecting a star.” In this topology, all workstations are connected to a central hub (Token Ring) in a physical star topology.
Central Hub – is an intelligent device that is using the serial connection provides jumpers out of one station to the entrance of another station. other words, using a hub, each station is connected only with the other two stations (previous and next stations). Thus, the workstations are connected the cable loop on which data packets are transmitted from one station to another, and each station retransmits these packets sent. Each workstation is available for this transceiver, which allows you to manage data flow in the network. Physically, such a network is the type of topology “star.” hub creates the primary (main) and backup rings. If the base ring will break, it can be circumvented by using redundant ring, because it uses four-core cable. Refusal station or open lines of communication workstation vlichet not in denial as a network topology ring because otklyuchet faulty hub station and close the circle transmission.
In architecture, Token Ring token is passed from node to node in the logical ring, create a central hub. This transfer is a marker in a fixed direction (the direction of motion and the marker data packets submitted by arrows blue). The station, which has a token can send data to another station. To transfer data workstations must first wait for the arrival of the free marker. In the marker contains the address of the station that sent this marker, as well as the address of the station to which it is intended. After that, the sender passes the token to the next station network to and that could send its data. One of nodes (typically by a file server), a token that is sent in a ring network. This node is an active monitor that ensures that the marker has been lost or destroyed. Advantages network topology Token Ring:
- topology provides equal access to all workstations;
- high reliability because the network is resistant to faults of individual stations and upon disconnection of individual stations. Disadvantages network topology Token Ring: high consumption and thus expensive cable wiring lines.