What is Bus Topology?
A bus topology is a network where each device is connected to a cable that extends from one end of the network to the other. This type of topology is often called a Line topology. In a bus topology, data is transmitted in only one direction. If the bus topology has two endpoints, it is called a Linear bus topology.
In this bus network topology, all computers are connected by a coaxial cable. This cable is called the backbone cable. The terminator terminates both ends of the backbone cable. To connect your computer to a backbone cable, use a drop cable. To connect the drop cable to the computer and the backbone cable, a BNC plug and a BNC T connector are used, respectively.
The logical bus topology directs all devices in the network through a cable that extends in a single direction from one end of the network to the other, which is sometimes called a “line topology” or a “backbone topology.” Data flow on the network also follows the route of the cable, moving in one direction.
Bus Topology Diagram
It is mainly used for small networks. Small networks with this topology use coaxial or RJ45 cables to link the devices together. However, the bus topology layout is outdated, and you are unlikely to encounter companies using bus topology today.
Features of Bus Topology Network
- It only transfers data in one direction.
- Each device is connected to one cable.
- Simplicity is the simplest and most commonly used method in Ethernet.
- Long cables act as a backbone network connecting all devices in the network.
- Use fewer cables than other topology.
- All nodes of the bus topology are directly connected to the link, and there are no other connections between the nodes.
- Physically, each host is connected to a standard cable, so although a disconnected cable can cause the host to disconnect, they can communicate directly.
- No signal is generated on each node or router.
- The number of devices connected to the bus affects network performance.
- Compared to the point-to-point topology, it is clear that the bus topology has major advantages because the instant point-to-point topology can only provide access to two nodes, while the bus topology allows multiple nodes to communicate.
- This means that multiple different computers, printers, routers, or other data devices can be connected to this network. For small area connections such as small business or small school networks, this makes the bus topology a better choice.
Bus Topology Working
- The type of wiring used can be coaxial cable, twisted pair, or fiber optic.
- Information travels through the cable in both directions at approximately 10/100 Mbps, or with resistance at both ends (terminals).
- Network data sent to all computers on the network as electronic signals. Only one computer can send messages using this topology at a time.
- A computer connected to the bus, or transmitting data to other computers on the network, or a computer that expects to receive data from another computer.
- The bus topology is not responsible for transferring data from one computer to another. Therefore, if the computer fails, it will not affect the rest of the network.
- To prevent the signal from bouncing across the cable, a terminator is placed at each end of the cable to absorb all signals. It allows the cable to be released from these signals so that other computers can send data.
Using bus topology, a computer sends a signal; the signal travels along the length of the cable in both directions from the sending computer. When the signal reaches the end of the cable length, it bounces back and returns to the direction it came from. This is called a signal bounce. Signal bounce can cause problems in computer networks because if another signal is sent on the cable at the same time, the two signals will collide. Collisions in computer networks can greatly reduce the performance of computer networks.
Bus Topology Examples
- An example of a bus topology is connecting two floors through a single line.
- Ethernet also uses a Ethernet bus topology.
- In a bus topology, one computer on the network acts as a server, and the other computers act as clients. The purpose of the server is to exchange data between client computers.
- You can use a bus topology network to add printers, scanners, and other input/output devices in the office/home.
Bus Network Terminators
A terminator is a device that provides resistance at the end of a transmission line to absorb transmission line signals, so it prevents them from rebounding and being received again by a network site.
The best cable that can be used in a bus network is a coaxial cable because it is the safest and gives you higher speed and network resistance.
Bus Network Topology Advantages and Disadvantages
- Easy to install and maintain.
- Cheap because it requires less wiring.
- Comfortable for small temporary networks.
- The internet and cables can be used simultaneously.
- Easy to expand by connecting two bus topology cables.
- Easy to connect a computer or peripheral to a linear bus.
- If any computer or device fails, it will not affect other devices or networks.
- The entire network does not rely on any central elements, and the failure of these elements will prevent all sites from working properly.
- Limited cable length.
- It needs a lot of maintenance.
- The speed of this network connection is insufficient.
- Slower because one computer is transferred at a time.
- Loss of signal over long distances (repeaters can be used).
- High transmission loss due to collisions between messages.
- Terminators are required at both ends of the backbone cable.
- It cannot be used as a standalone solution in large buildings.
- If the backbone cable is damaged, the entire system/network will fail.
- If any equipment failure occurs, it is difficult to find failure in the network.
- It is called a passive topology because the computer does not regenerate signals.
- Correct termination is required to prevent signal bounce. It would be best if you used a terminator.