bridge vs hub difficult to understand

Question

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What is the difference between a hub and a switch?

i find it difficult to understand the difference between a hub and a bridge. Please help me. :(

Answer 1

There is a better question to answer than your original bridge vs hub: Instead start with the difference between a bridge vs a repeater and then move onto a switch vs hub.

A repeater unquestioningly always forwards packets from one LAN segment to another. A bridge does this selectively by knowing (and learning) which devices are on which side of it and only forwarding packets which are actually originating on one side and going to a host in the other side.

Having understood this distinction between repeater and bridge, hubs are now simply multi-port repeaters and switches are multi-port bridges, where each port on the switch is a separate collision domain.

Answer 2

Hubs and repeaters replicate packets coming in to all of their ports unconditionally. Bridges and switches attempt to only send packets to the port leading to their destination, thus helping to reduce network congestion. Additionally, full duplex operation is only possible when connecting directly to a switch or bridge.