Terminator in bus topology

Computers and peripheralsare called nodes and are each connected to a single cable on which datacan be sent. A bus network topology has a terminatoron each end. These are needed to ensure that the network functions correctly.

The bus carries data along a central cable. As the data arrives at each computer system, it checks the destination address to see if it matches. If the address does not match, the node ignores the packet. If the address of the node matches that contained in the data, it processes the data.

Advantages and disadvantages of using a bus network topology

Having nodes arranged in a bus network topology brings some benefits:

• it is easy to implement and to add more nodes to the network
• it is quick to set up
• it uses less cabling than some other network topologies and is therefore cost effective

However, bus network topologies also have disadvantages:

• it can be difficult to find out where an error has occurred
• as more nodes are added, the performance of the network can be reduced, making this unsuitable for large local area networks (LANs)
• if there is a problem with the main bus cable, the entire network stops working
• as all computers on the bus can see all data that is transmitted, it is not classed as a secure network and can easily be hacked
• data collisions are more likely, which causes the network to slow down

Bus network topologies in use

Bus network topologies are used when a small, cheap and often temporary network is needed that does not rely on very high data-transfer speeds. They may be used in locations such as a laboratory or office.