Network Reliability and Fault-Tolerance

When we make a telephone call, the call is connected through a communication network to the receiving party. Similarly, when we send an e-mail using the Internet, the message is sent through a communication network to the recipient. Such communication networks are made up of nodes and links that connect the nodes by hardware as well as the software components that allow for the functionality to communicate through such networks. Network reliability refers to the reliability of the overall network to provide communication in the event of failure of a component or components in the network. The term fault-tolerant is usually used to refer to how reliable a particular component (element) of a network is (e.g., a switch or a router). The term fault-tolerant network, on the other hand, refers to how resilient the network is against the failure of a component.