Collisions are often in a hub environment, because each port on a hub is in the same collision domain. By contrast, each port on a bridge, a switch or a router is in a separate collision domain. We have 6 collision domains in the example above. Remember, each port on a hub is in the same collision domain.

How many collision domains do a hub has?

Hubs send out information to all hosts on the segment, creating a shared collision domain. Switches have one collision domain per port and keep an address table of the MAC addresses that are associated with each port.

Does hub have collision domain?

All the devices connected to a hub are in a single collision and single broadcast domain. Remember, hubs do not segment a network, they just connect network segments.