Bus Topology

The Bus Topology is also known linear bus. It consists of several computers which are attached to a common cable called the trunk line.

Bus Network

In the bus topology, data on the network is sent to all the computers on the network. However, the data is accepted only by the computer that has the address matching the address in the signal. Only one computer at a time can send messages. The bus topology is a passive topology in which the computers on the bus are not responsible for moving data. In this, failure of one computer does not affect the performance of the network. The performance on a bus network can be affected by the following factors:

• Number of computers on the network
• Hardware capabilities of computers on the network
• Frequency of data transmission
• Types of cable used on the network
• Distance between computers on the network

Note: Every computer on the network has an address. Data that is sent from a computer that contains the address of the computer to which it is sent.

The Advantages and Disadvantages of Each Type of Topology

Topology	Advantages	Disadvantages
Bus Topology	Uses the least amount of cable. Media is inexpensive, simple and reliable. Is easy to extend.	Hardware bugs are difficult to isolate. Does not adequately support large number of I/O requests from users. Cable break can affect many users.
Ring Topology	Networks can cover greater distances. Performance is even despite many users.	Expanding the system can be costly. Network reconfiguration disrupts operation.
Star Topology	New computers can be easily added. Cable layouts are easy to modify. Failure of one computer does not affect the rest of the network.	Uses a large amount of cable. If the centralized point fails, the network fails.

Advantages and Disadvantages of the Standard Topologies