Characteristics of a Computer Network: Topology
The graphical arrangement of computer systems, or nodes to form a computer network, is called the network topology. A network topology can be one of two types: physical topology and logical topology.
Physical topology refers to the physical arrangement of computer nodes based on hardware configuration while logical topology defines how data is flowing through the network.
Both topologies exist in a Local Area Network (LAN). All the nodes in LAN are connected with each other through a valid media which shows its physical arrangement based on hardware used while data flow through this arrangement shows logical topology.
There are many types of physical topology. Some popular types are discussed as follows:
1. Peer–to–Peer Arrangement
Sometimes this is called as a point-to-point link. Each point–to–point link contains one transmitter and one receiver. Each station receives data exactly from one transmitter and each transmitter transmits data to exactly one receiver. Receiving and transmission process can be done over a single wire or can use separate wires for better performance.
2. Bus Topology
Bus topology is also called as point–to–multi–point arrangement. In a bus topology, all nodes or devices are linked with one transmitter or server computer via a single cable (mostly coaxial cable) called Backbone. All nodes are connected to the bus cable by drop lines. A drop line is a connection running between the nodes and the main cable.
3. Star Topology
In a star topology, each node has a dedicated point–to–point connection only with a central server, normally called a hub. The nodes are not directly connected to each other. Hence, direct data flow is not allowed in between the nodes. The central server or hub acts as a data exchanger as one node sends data exactly to hub and hub transmits this data to another node.
4. Tree Topology
Tree topology is a combination of one or more star topology arrangements. All the sub-central hubs are connected to a main central hub to form a tree topology. A cable TV network is a good example of this type of topology.
5. Ring Topology
In a ring topology, each node has a dedicated point–to–point line configuration only with the two nodes on either side of it. A signal is passed along the ring in one direction, from node to node, until it reaches its receiver. Each node in the ring is integrated as a repeater. When a node receives a signal intended from another node, its repeater regenerates the bits and passes them along.
6. Mesh Topology
In a mesh topology, each node has a dedicated point–to–point connection with rest of the nodes in the network. Dedicated connection means data can only be flown between two nodes, it connects.
7. Hybrid Topology
This topology is a common arrangement of one or more topologies described above. It means one or more above described topologies connected with each other to form a hybrid network arrangement.
© 2018 Karun Gaur