Star networks are one of the most common computer network topologies. In its simplest form, a star network consists of one central node, typically a switch or hub, which acts as a conduct to transmit messages. In star topology, every node (computer workstation or any other peripheral) is connected to a central node. The switch is the server and the peripherals are the clients.
A star network is an implementation of a spoke–hub distribution paradigm in computer networks. Thus, the hub and leaf nodes, and the transmission lines between them, form a graph with the topology of a star. Data on a star network passes through the hub, switch, or concentrator before continuing to its destination. The hub, switch, or concentrator manages and controls all functions of the network. It also acts as a repeater for the data flow. This configuration is common with twisted pair cable and optical fibre cable. However, it can also be used with coaxial cable.
The star topology reduces the impact of a line failure by connecting all of the systems to a central node. When applied to a bus-based network, this central hub re-broadcasts all transmissions received from any peripheral node to all peripheral nodes on the network, sometimes including the originating node. All peripheral nodes may thus communicate with all others by transmitting to, and receiving from, the central node only. The failure of a transmission line linking any peripheral node to the central node will result in the isolation of that peripheral node from all others, but the rest of the systems will be unaffected.