When two or more than two computers are connected with each other using any medium in such a way that they communicate with each other and share their resources then it is called computer network and a physical interconnection of a variety of elements including in a network is called topology. Topology is the structure or arrangement of a network which may be physical or logical. Physical topology included devices, location and installation of cables etc. and Logical topology included fact that where and how data transmit from one location to another location in a network.
Types of Computer Network Topologies
There are different types of network topologies which are in use .The type of network topology depend on the requirement of related institute. Topologies types are under
- Bus Topology
- Star Topology
- Ring Topology
- Mesh Topology
Bus Topology is used for small and simple network. Bus topology connects all computers in a linear shape with a backbone to connect all computers. A single cable is used to connect all computers devices with interface connector. A single device send message towards other devices attached with it but only intentional recipient accept and process the message. The compulsory part of Bus topology is backbone because if it fails then there is no communication possible among computers. In-fact Bus topology has some advantages such as it is very easy and understandable. There is no much wires used for connectivity therefore it is less expensive. A user can easily extend a Bus topology because two cables can easily joined with a one long cable which is Barrel connector. Bus Topology have some drawbacks that its speed become slow with heavy traffic and then only one computer can send any message., The troubleshooting of Bus Topology also very difficult. If any cable is loose or break from any part then all activities are stopped and the rest of the devices or computers connected to the network stop responding.
A central device like hub, router and switch is used to connect all computers in a star topology. The functionality of connected devices is entirely different from each other in star topology because it may be Shielded Twisted Pair (STP) cable or UTP cabled. The STP stands for shielded twisted pair cable and UTP stands for unshielded pair cable. It is a most usable topology in local area network from all over the world. Star topology can be easily put into practice in offices, café, offices, travel agencies, or in a building. For star topology we need many devices and cables as compared to Bus topology. Star topology has some benefits such as it is easy to configure, and you can easily increase computers in a network without any disturbance. You can easily diagnose the error due to central device. In star network if any cable or node failure then there is no effect on entire network but if switch, hub or router failure then all network lay down. The drawbacks of Star topology is that it is an expensive because all computers connected with central device via cables .
In Ring Topology all computers are situated in the form of a ring and each computer connected within two neighbor’s computer by the means of communication. In Ring topology all computers communicate with each other clockwise or anti clockwise. Generally FDDI, Token ring and SONET used to configure ring topology. The use of ring topology increasing day by day because a network can easily implement in home, office, building, and school .Ring topology have some benefits such as equal access to every one, transformation of data at very high speed but have disadvantages like The fault in any cable or wire may cause of failure network., trouble shooting also a major problem.
Mesh topology designed on the concept of Router because its all work depends on router. When a user send any message to any other user then router search any shortest way to reach their destination. In all other topologies messages are usually send and receive to every computer but in mesh topology message find its way for destination. If all devices connected to all other devices then it’s called full mesh topology but if a device connected indirectly to the other then it is called partial mesh.