Star network
From Free net encyclopedia
Image:Star-Topology.gif Star networks are one of the most common computer network topologies. In its simplest form, a star network consists of one central switch, or hub computer which acts as a router to transmit messages.
When applied to a bus-based network, this central hub rebroadcasts 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.
If the central node is passive, the originating node must be able to tolerate the reception of an echo of its own transmission, delayed by the two-way transmission time (i.e. to and from the central node) plus any delay generated in the central node. An active star network has an active central node that usually has the means to prevent echo-related problems.
Comparing star networks to other types of network
- Easy to implement and extend, even in large networks
- Well suited for temporary networks (quick setup)
- The failure of a non-central node will not have major effects on the functionality of the network.
- Reliable market proven system
- No problems with collisions of Data since each station has its own cable to the server/hub.
- Security can be implemented in the hub/switch.
Disadvantages
- Limited cable length and number of stations
- Maintenance costs may be higher in the long run
- Failure of the central node can disable the entire network.
- One virus in the network can affect them all.
- Depending on the transmission media, length limitations may be imposed from the central location used.
See also
es:Red en estrella pt:Rede em estrela ru:Звезда (топология компьютерной сети) ta:விண்மீன் வலையமைப்பு zh:星型网