Physical Network Topologies
1. Bus Topology
In a bus topology, all devices are connected to a single central cable, known as the bus or backbone. Data transmitted on the bus is received by all devices connected to it. Each device checks the destination address of the data packet to determine if it should process the data.
Key Features:
- Simple and easy to implement.
- Cost-effective as it requires less cable.
- If the central cable fails, the entire network is affected.
Example: Think of a bus topology as a single highway. All vehicles (data packets) travel on this highway, and each driver (device) checks the destination address to see if the package is meant for them. If the highway is blocked, all traffic stops.
2. Ring Topology
In a ring topology, each device is connected to exactly two other devices, forming a circular path. Data travels in one direction around the ring, passing through each device until it reaches its destination. Each device acts as a repeater to boost the signal.
Key Features:
- Data travels in a single direction, reducing the risk of collision.
- If one device or cable fails, it can disrupt the entire network.
- Symmetric design allows for balanced traffic distribution.
Example: Imagine a ring topology as a circular track. Each runner (data packet) passes the baton (data) to the next runner in a clockwise direction. If one runner drops the baton, the relay race is disrupted.