Bus topology

A bus topology is one in which every single node on the network is connected to every other node on the network by way of a single channel of communication, as seen in the following diagram:

Each connection coming off of a node is joined to a shared connection between all nodes by way of a simple connection interface. Any packets sent by a node on a bus topology will be transmitted on the same bus as every other packet transmitted over the network, and each node on the bus is responsible for identifying whether or not it is the most suitable node to service the request carried by that packet. Similar to the linear network previously described, packets on a bus topology must contain information about the target node for the request.

As is the case with each of the topologies of lesser complexity, the bus topology has the obvious benefit of a low upfront cost of implementation, and relatively low overheads for orchestration. Hopefully, however, the previous description I provided helps to characterize the particular challenges associated with this particular network topology. Because all network communication happens over a single channel, all traffic, even under ideal circumstances, is limited by the bandwidth of that channel. Especially chatty software doesn't do well on a bus topology, as it tends to monopolize the link between nodes.

Additionally, because there is only a single channel of communication across the whole of the network, that channel serves as a single point of failure for the network. If the central bus comes offline, then each node is isolated simultaneously.