Types of network topology, hub, switch, router, repeater and brouter

Geometric representation of how the computers are connected to each other is known as topology. There are five types of topology – Mesh, Star, Bus, Ring and Hybrid.

1. Types of Network Topology Topology defines the structure of the network of how all the components are interconnected to each other. There are two types of topology: physical and logical topology. https://www.slideshare.net

2. Bus Topology https://www.slideshare.net/ The bus topology is designed in such a way that all the stations are connected through a single cable known as a backbone cable. Each node is either connected to the backbone cable by drop cable or directly connected to the backbone cable. When a node wants to send a message over the network, it puts a message over the network. All the stations available in the network will receive the message whether it has been addressed or not. The bus topology is mainly used in 802.3 (Ethernet) and 802.4 standard networks. The configuration of a bus topology is quite simpler as compared to other topologies. The backbone cable is considered as a "single lane" through which the message is broadcast to all the stations. Advantages : • If N devices are connected to each other in a bus topology, then the number of cables required to connect them is 1, which is known as backbone cable, and N drop lines are required. The cost of the cable is less as compared to other topologies, but it is used to build small networks. Disadvantages : o If the common cable fails, then the whole system will crash down. o If the network traffic is heavy, it increases collisions in the network. To avoid this, various protocols are used in the MAC layer known as Pure Aloha, Slotted Aloha, CSMA/CD, etc. o Security is very low.

3. ring topology Ring topology is like a bus topology, but with connected ends. The node that receives the message from the previous computer will retransmit to the next node. The data flows in one direction, i.e., it is unidirectional. The data flows in a single loop continuously known as an endless loop. It has no terminated ends, i.e., each node is connected to other node and having no termination point. The data in a ring topology flow in a clockwise direction. Advantages: The possibility of collision is minimum in this type of topology. Cheap to install and expand. Disadvantages: • Troubleshooting is difficult in this topology. • The addition of stations in between or removal of stations can disturb the whole topology. Less secure. https://www.slideshare.net/

4. Star topology Star topology is an arrangement of the network in which every node is connected to the central hub, switch or a central computer. The central computer is known as a server, and the peripheral devices attached to the server are known as clients. • Coaxial cable or RJ-45 cables are used to connect the computers. Hubs or Switches are mainly used as connection devices in a physical star topology. Star topology is the most popular topology in network implementation. . Advantages: If N devices are connected to each other in a star topology, then the number of cables required to connect them is N. So, it is easy to set up. Each device requires only 1 port i.e. to connect to the hub, therefore the total number of ports required is N. Disadvantages: • If the concentrator (hub) on which the whole topology relies fails, the whole system will crash down. • The cost of installation is high. • Performance is based on the single concentrator hub. https://www.slideshare.net/

5. Tree Topology Tree Topology is a topology which is having a tree structure in which all the computer are connected like the branches which are connected with the tree. In Computer Network, tree topology is called as a combination of a Bus and Start network topology. The main advantages of this topology are these are very flexible and also have better scalability. Advantages of Tree Topology : This topology is the combination of bus and star topology. This topology provides a hierarchical as well as central data arrangement of the nodes. As the leaf nodes can add one or more nodes in the hierarchical chain, this topology provides high scalability. The other nodes in a network are not affected, if one of their nodes get damaged or not working. Tree topology provides easy maintenance and easy fault identification can be done. Disadvantages of Tree Topology : This network is very difficult to configure as compared to the other network topologies. Length of a segment is limited & the limit of the segment depends on the type of cabling used. Due to the presence of large number of nodes, the network performance of tree topology becomes a bit slowly. If the computer in first level is erroneous, next level computer will also go under problems. Requires large number of cables compared to star and ring topology. As the data needs to travel from the central cable this creates dense network traffic. /www.geeksforgeeks.org