NETAD LESSON3

Network Topology

is the way devices are connected in a network. It defines how these components are connected and how data transfer between the network.

Physical Network topology and Logical Network Topology

There are two major categories of Network Topology

Physical Network Topology

refers to the actual structure of the physical medium for the transmission of data.

Logical network Topology

 refers to the transmission of data between devices present in the network irrespective of the way devices are connected.

Types of Network Topology

• Point to Point Topology

• Mesh Topology

• Star Topology

• Bus Topology

• Ring Topology

• Tree Topology

• Hybrid Topology

Point-to-Point

is a type of topology that works on the functionality of the sender and receiver. It is the simplest communication between two nodes, in which one is the sender and the other one is the receiver. it provides high bandwidth.

Mesh Topology

every device is connected to another device via a particular channel. Every device is connected to another via dedicated channels. These channels are known as links. In this topology, the protocols used are AHCP (Ad Hoc Configuration Protocols), DHCP (Dynamic Host Configuration Protocol), etc.

Star Topology

all the devices are connected to a single hub through a cable. This hub is the central node and all other nodes are connected to the central node. The hub can be passive in nature i.e., not an intelligent hub such as broadcasting devices, at the same time the hub can be intelligent known as an active hub. Active hubs have repeaters in them. Coaxial cables or RJ-45 cables are used to connect the computers. In this topology, many popular Ethernet LAN protocols are used as CD(Collision Detection), CSMA (Carrier Sense Multiple Access), etc.

Bus Topology

is a network type in which every computer and network device is connected to a single cable. It is bi-directional. It is a multi-point connection and a non-robust topology because if the backbone fails the topology crashes. In this Topology, various MAC (Media Access Control) protocols are followed by LAN ethernet connections like TDMA, Pure Aloha, CDMA, Slotted Aloha, etc.

Ring Topology

it forms a ring connecting devices with exactly two neighboring devices. A number of repeaters are used for this topology with a large number of nodes, because if someone wants to send some data to the last node in this topology with 100 nodes, then the data will have to pass through 99 nodes to reach the 100th node. Hence to prevent data loss repeaters are used in the network.

The data flows in one direction, i.e. it is unidirectional, but it can be made bidirectional by having 2 connections between each Network Node, it is called Dual Ring Topology. In-Ring Topology, the Token Ring Passing protocol is used by the workstations to transmit the data

Tree Topology

is the variation of the Star topology. This topology has a hierarchical flow of data. In This Topology, protocols like DHCP and SAC (Standard Automatic Configuration) are used.

Hybrid Topology

is the combination of all the various types of topologies we have studied above. It is used when the nodes are free to take any form. It means these can be individuals such as Ring or Star topology or can be a combination of various types of topologies