What is the need of a broadcast domian?
A broadcast domain is a logical division or a valid division of a computer network where all nodes can contact each other by means of broadcast at the data link layer. It is a domain where a broadcast is forwarded. All ports on a hub or on a switch are in the same broadcast domain by default.
All ports in a router are in different broadcast domains. Also, routers don’t forward or send broadcasts from 1 broadcast domain to another. A collision domain, on the other hand, is a part or division of a network where packet collisions can happen. A collision happens when 2 devices send a packet simultaneously on the shared network segment.
When this happens, the packets collide and both devices have to send the packets again which then decreases the network efficiency.