Bus Topology

Bus Topology is a networking topology that connects networking components along a single cable or that uses a series of cable segments that are connected linearly.

What is Bus Topology?

A networking topology that connects networking components along a single cable or that uses a series of cable segments that are connected linearly. A network that uses a bus topology is referred to as a “bus network.” Bus networks were the original form of Ethernet networks, using the 10Base5 cabling standard. Bus topology is used for:

  • Small workgroup local area networks (LANs) whose computers are connected using a thinnet cable
  • Trunk cables connecting hubs or switches of departmental LANs to form a larger LAN
  • Backboning, by joining switches and routers to form campus-wide networks

    Bus topology architecture

Bus topology is the cheapest way of connecting computers to form a workgroup or departmental LAN, but it has the disadvantage that a single loose connection or cable break can bring down the entire LAN.

NOTE

A hub or concentrator on an Ethernet network is really a collapsed bus topology. Physically, the network appears to be wired in a star topology, but internally the hub contains a collapsed bus, creating a configuration called a star-wired bus. However, in this case, a failure in one of the cables does not affect the remaining network.

TIP

Communication problems on bus networks might indicate that the bus ends are improperly terminated. A break in the cable will produce a similar result, since the ends of the break are not terminated. Use a cable tester to determine the nature and location of the problem.