What's the difference between a hub, a switch, and a router?

What's the difference between a hub, a switch,a bridge,a repeater and a router?

• Hubs

A hub is typically the least expensive, least intelligent, and least complicated of the three.
It's job is very simple - anything that comes in one port is sent out to the others.
Hub: Layer 1device, just a multi-port repeater and works on physical layer

• Switches

A switch does essentially what a hub does, but more efficiently.
By paying attention to the traffic that comes across it, it can "learn" where particular addresses are.
Switch: Layer 2 device, can work on data link layer

• Routers

A router is the smartest and most complicated.
a router operates exactly as a switch, learning the location of the computers on its connections and routing traffic only to those computers
Router: Layer 3 device, can work on physical, data and network layer

• Bridge

Bridge: Layer 2 device, can work on data link layer.

Reference:
http://ask-leo.com/whats_the_difference_between_a_hub_a_switch_and_a_router.html


Switches, and Routers, and Hubs! Oh my!
http://www.youtube.com/watch?v=reXS_e3fTAk&feature=related

• 1- What is the difference between a hub and a switch?

In the case of a hub, it broadcasts all data to every port. This can make for serious security and reliability concerns, as well as cause a number of collisions to occur on the network.
Switches on the other hand create connections dynamically, so that usually only the requesting port can receive the information destined for it.

http://resources.infosecinstitute.com/ramp-5-levels-top-50-network-administrator-interview-questions/