A ring network is a network topology in which nodes or terminals are connected to only two other terminals at a time in what is called a closed loop configuration. Adjacent node pairs are directly connected, while every other node is indirectly connected. If data needs to go to a node that is further away, it will pass through all the nodes between the sender and the receiver.
This topology is used for networks with modest budgets and specifications. Ring networks need minimal cabling since only the two nearest nodes need to be connected with each other.
In a ring network, every node is only connected to the node that is directly adjacent to it until a ring is formed. All data from a sender node must pass all the nodes between that sender and the receiver node, which means that all nodes must be able to handle data packets.
There are some disadvantages to this type of network topology. The biggest issue is that when one node fails, the whole network may fail. To overcome this issue, a dual-ring network may be implemented. This creates two directions for data: clockwise and counterclockwise. In the event of a node failure, data is wrapped back on the ring in the opposite directing, effectively allowing data to reach all the other nodes and creating a c-shaped ring.
Dual-ring network protocols include Spatial Reuse Protocol, Resilient Packet Ring Protocol and Fiber Distributed Data Interface Protocol.