Star TopologyStar Topology is the most popular and widely used network topology in local area networks. In star topology, all computers are connected with a central device known as HUB or Switch. Now-a-days Hubs are often replaced by Fast Network Switches. The sender computer sends data to the hub. The hub sends it to the destination computer. So, all data communication is managed through HUB or Switch.
Note: The major difference between a Networking Hub and Networking Switch is that HUB sends data to all computers, and the destination computer will accept it while other computers will not. On the other hand, Switch sends data only to the destination computer. Therefore, switch can reduce network traffic and hence provides fast transmission speed.
Advantages of Star Network Topology
1. Easy Installation and maintenanceIt is easy to maintain network. That is why it is so popular.
2. Adding or removing computersAdding or removing computers can be done without disturbing the network. We connect the new computer with the HUB by means of a networking cable. One end of the cable (RJ 45 connector) is inserted in computer’s Network Interface Card and the other end (RJ 45 connector) is plugged into the HUB, and that’s it.
3. Fault DiagnosisIn a star network topology, finding faults is easy. If a computer is no more connected with your network, you can check its cable and connectors or network settings in its Operating system.
4. Network ReliabilitySingle computer failure will not disturb whole network, since all other computers are connected with separate links ( wires ) to HUB. Definitely, they will work fine.
5. Better performanceStar topology can prevents the passing of data through an excessive number of nodes. By using a Switch, at most, 3 devices and 2 links are involved in any communication between any two devices.
6. Device Isolation
Each device is separately connected to HUB or Switch and is isolated. This is why each device works independently.
Disadvantages of Star Network Topology1. In star network topology, data communication depends on HUB. If central hub fails, then whole network fails.
2. Since each computer will be connected with HUB by means of a separate wire, star network topology needs more cable to connect computers.
3. It is more expensive due to more wires.