Network Topology

What is Network Topology?

      In communication networks, a topology is a usually schematic description of the arrangement of a network, including its nodes and connecting lines. There are two ways of defining network geometry: the physical topology and the logical (or signal) topology.

       Computers in a network are physically set up using various arrangement of topologies. Here are some of the different types of network setup or topology:

• Bus Topology -  a network setup where each of the computers and network devices are connected to a single cable or backbone. Every workstation is connected to a main cable called the bus. Therefore, in effect, each workstation is directly connected to every other workstation in the network. If the network cable breaks, the entire network goes down.

• Star Topology - a very common network setup where each of the devices and computers on a network connect to a central bulb. Every workstation is indirectly connected to every other through the central computer.A major disadvantage is if the central hub fails, all computers connected to that hub will be disconnected.

• Tree Topology - a very common network setup that is similar to a bus topology and a star topology. It connects multiple star networks to other star networks. The central computers of the star networks are connected to a main bus. Thus, a tree network is a bus network of star networks. However, if the main cable or trunk between each of the two star topology networks failed, those networks would unable to communicate with each other.

• Mesh Topology - a network setup where each of the computers and network devices are interconnected with one another in all possible or partial combinations, allowing for most transmission to be distributed, even if one of the connection goes down. This topology employs either of two schemes, called full mesh and partial mesh. In the full mesh topology, each workstation is connected directly to each of the others. In the partial mesh topology, some workstations are connected to all the others, and some are connected only to those other nodes with which they exchange the most data.

• Ring Topology - configuration where network computer and device are connected to each other forming a large circle. Each packet is sent around the ring until it reaches its final destination. Today , the ring topology is seldom used.