In star-bus topology, why is it logical bus?

Question

It's obvious that it's physical star b/c the way machines are connected. In my book, a number of computers are connected to a central hub.

But I don't get why it's logical bus. Someone here was saying it's because data will be sent through all machines which is the characteristic of the bus topology.

But, then again, in a logical star, it seems the data should reach all machines as well because we have a central device (a hub, in this case) to pass information to all computers. Therefore, there's no difference between the logical bus and logical star. Then, how can we conclude it's a logical bus?

Thanks in advance!

Answer 1

Since a number of computers are connected using a hub, your hubs must be linked together like a bus network. Logical refers to how the data is sent. I think the key word in your problem is the fact they you are using a hub. With using a hub, all the computers will see the data that is transmitted but only the one it is intended for will read it. This would also occur with a star using a hub as well. If we change the hub to a smart or managed switch or even a router, then the data will only go to the computer it was intended for, thus giving us a logical star instead of a logical bus.

Answer 2

BUS topology: All devices are connected to a central cable, called the bus or backbone. Bus networks are relatively inexpensive and easy to install for small networks. Ethernet systems use a bus topology. RING topology : All devices are connected to one another in the shape of a closed loop, so that each device is connected directly to two other devices, one on either side of it. Ring topologies are relatively expensive and difficult to install, but they offer high bandwidth and can span large distances. STAR topology: All devices are connected to a central hub. Star networks are relatively easy to install and manage, but bottlenecks can occur because all data must pass through the hub.