Bus topology is a network topology in which all nodes (devices such as computers, printers, and servers) are connected to a single communication channel, called a bus. In a bus topology, the bus serves as a shared communication medium to which all nodes have access.
Key characteristics of bus topology include:
Single Communication Channel:
The network consists of a single communication channel (the bus) that connects all nodes. This channel can be a physical cable or a wireless communication medium.
The ends of the bus are terminated with terminators to prevent signal reflection. Without terminators, signals could bounce back and interfere with communication on the network.
Bus topology is considered a passive topology because the nodes do not actively participate in the transmission of data. Instead, they share the communication channel.
All nodes share the same communication medium. When one node sends data, all other nodes on the bus receive the signal, but only the intended recipient processes the data.
Collisions can occur in bus topology when two or more nodes attempt to transmit data simultaneously. Collision detection and resolution mechanisms are essential to manage this issue.
Bus topology is relatively easy to install and requires less cabling than some other topologies. It is often used in small to medium-sized networks where simplicity and cost-effectiveness are priorities.
Bus topology may face limitations in terms of scalability. As more nodes are added to the bus, the potential for collisions and network congestion increases, which can negatively impact performance.
Single Point of Failure:
The bus itself represents a single point of failure. If the bus cable is damaged or fails, the entire network may be affected. Redundancy measures are often implemented to address this vulnerability.
Performance Degradation with Heavy Traffic:
As the number of nodes or the volume of traffic increases, the performance of the bus topology may degrade due to collisions and increased contention for the shared communication channel.
Bus topology was more common in the early days of networking but has been largely replaced by other topologies, such as star and ring topologies, in modern networks. While bus topology is simple and cost-effective, its limitations regarding scalability and potential for collisions make it less suitable for larger and more complex networks.