What characterizes a bus network topology?

A bus network topology is characterized by all devices connecting through a single circuit. In this setup, all network nodes share a common communication line, which is referred to as the "bus." This means that data packets are sent along this single communication path, where every device on the bus can listen to the data transmitted. However, only the intended recipient processes the data, while others ignore the information.

This configuration is straightforward and cost-effective, particularly for small networks, as it requires less cabling than other topologies. However, it can become less efficient with an increase in devices because all devices share the same communication medium, which may lead to data collisions and increased network traffic.

In contrast, the characteristics of the other options do not accurately describe a bus topology. A closed-loop is indicative of a ring topology, dedicated lines suggest a star topology, and multiple directional data movement relates to a network using a multipoint or mesh configuration. Therefore, the defining feature of a bus network is indeed that all devices link through a single circuit.