Ring Network Topology
What is a Ring Network Topology
A ring network is a network topology in which each node connects to exactly two other nodes, forming a single continuous pathway for signals through each node - a ring. Data travels from node to node, with each node along the way handling every packet.
Because a ring topology provides only one pathway between any two nodes, ring networks may be disrupted by the failure of a single link. A node failure or cable break might isolate every node attached to the ring.
FDDI networks overcome this vulnerability by sending data on a clockwise and a counterclockwise ring: in the event of a break data is wrapped back onto the complementary ring before it reaches the end of the cable, maintaining a path to every node along the resulting "C-Ring".
Many ring networks add a "counter-rotating ring" to form a redundant topology. Such "dual ring" networks include Spatial Reuse Protocol, Fiber Distributed Data Interface (FDDI), andResilient Packet Ring.
802.5 networks -- also known as IBM Token Ring networks—avoid the weakness of a ring topology altogether: they actually use a startopology at the physical layer and a Multistation Access Unit (MAU) to imitate a ring at the datalink layer.
Advantages
- Very orderly network where every device has access to the token and the opportunity to transmit
- Performs better than a bus topology under heavy network load
- Does not require a central node to manage the connectivity between the computers
- Due to the point to point line configuration of devices with a device on either side (each device is connected to its immediate neighbour), it is quite easy to install and reconfigure since adding or removing a device requires moving just two connections.
- Point to point line configuration makes it easy to identify and isolate faults.
Disadvantages
- One malfunctioning workstation can create problems for the entire network. This can be solved by using a dual ring or a switch that closes off the break.
- Moving, adding and changing the devices can affect the network
- Communication delay is directly proportional to number of nodes in the network
- Bandwidth is shared on all links between devices
- More difficult to configure than a Star: node adjunction ⇨ Ring shutdown and reconfiguration