In which topology are all network devices connected to a common device called a hub or switch?

• A. Star topology
• B. Bus topology
• C. Ring topology
• D. Mesh topology

Answer: (A)

The main idea here is a central point that all devices connect to, creating a hub-and-spoke layout. Each device has its own link to a single central device (a hub or switch). This setup makes it easy to add or remove devices, and it helps isolate problems to a single branch of the network rather than affecting every device. With a switch, the central device also manages traffic efficiently by keeping each connection separate, which can improve performance. The trade-off is that if the central hub or switch fails, the entire network can go down because everything routes through that one point.

In other topologies, the connectivity patterns differ: a single shared cable in a bus topology means everyone talks on the same channel, so performance suffers as more devices join and any break can disrupt the whole network; a ring topology links devices in a circle and data travels around the loop, so a failure can break the ring unless there are protective mechanisms; a mesh topology interconnects devices with multiple paths, offering high resilience but at a much higher cost.