Page 49 - M. Abrahim Thesis

Computer Network 2021

Figure 2-23 shown an Extended- Star Topology of Network Devices

2.10.1.3 Ring Topology

The logical ring topology is another important topology in LAN connectivity. As the name
implies, hosts are connected in the form of a ring or circle. Unlike the physical bus topology, the
ring topology has no beginning or end that needs to be terminated. Data is transmitted in a way
unlike the logical bus topology. A frame travels around the ring, stopping at each node. If a node
wants to transmit data, it is permitted to add that data as well as the destination address to the
frame. The frame then continues around the ring until it finds the destination node, which takes
the data out of the frame. The advantage of using this type of method is that there are no
collisions of data packets.
Two types of rings exist: ■ Single ring ■ Dual ring

2.10.1.3.1. Single Ring, as shown in Figure 2-24, all the devices on the network share a
single cable, and the data travels in one direction only. Each device waits its turn to send data
over the network. Most single-ring topologies are actually wired as a star.

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