Network Topology

Definition

Computers in a network have to be connected in some logical manner. The layout pattern of the interconnections between computers in a network is called network topology. You can think of topology as the virtual shape or structure of the network. Network topology is also referred to as 'network architecture.'

Devices on the network are referred to as 'nodes.' The most common nodes are computers and peripheral devices. Network topology is illustrated by showing these nodes and their connections using cables. There are a number of different types of network topology 

         

Types of Network Topology

💻 STAR TOPOLOGY

💻 BUS TOPOLOGY

💻 RING TOPOLOGY

                     

STAR TOPOLOGY

• All the computers and other nodes on the network connect to a central device thus forming a star
• Use a central device (hub/switch) where are nodes connected using cables 
• Data travels passes through the hub/switch until reach destination
• Can be used with twisted pair, Optical Fibre or coaxial cable

Advantages of Star Topology

1. Fast performance with few nodes and low network traffic.
2. Hub can be upgraded easily.
3. Easy to troubleshoot.
4. Easy to setup and modify.
5. Only that node is affected which has failed, rest of the nodes can work smoothly.

Disadvantages of Star Topology

1. Cost of installation is high.
2. Expensive to use.
3. If the hub fails then the whole network is stopped because all the nodes depend on the hub.
4. Performance is based on the hub that is it depends on its capacity

       

BUS TOPOLOGY

• Consists of a single central to all computer and other nodes connect
• Single central cable (backbone) which connect all nodes on network using T-connecter
• Signals are send as electrical pulse that travel along the cable to all nodes and only recipient accept data
• Transmits data only in one direction.

Advantages of Bus Topology

1. It is cost effective.
2. Cable required is least compared to other network topology.
3. Used in small networks.
4. It is easy to understand.
5. Easy to expand joining two cables together.

Disadvantages of Bus Topology

1. Cables fails then whole network fails.
2. If network traffic is heavy or nodes are more the performance of the network decreases.
3. Cable has a limited length.
4. It is slower than the ring topology.

              

RING TOPOLOGY

• A cable form a closed loop (ring) with all computers and devices arranged along the ring
• Data travels from one node to another node in one direction until it reaches its destination by using token passing.

Advantages of Ring Topology

1. Transmitting network is not affected by high traffic or by adding more nodes, as only the nodes having tokens can transmit data.
2. Cheap to install and expand

Disadvantages of Ring Topology

1. Troubleshooting is difficult in ring topology.
2. Adding or deleting the computers disturbs the network activity.
3. Failure of one computer disturbs the whole network.