What is the difference between a switch, router and hub?

Question

What is the difference between a switch, router and hub?

Answer 1

Hub: device to connect several networked devices. All devices share the hub & any traffic from one device is seen by all devices. Leads to collisions when two devices transmit at the same time. Can also lead to broadcast storms when all devices transmit at once.

Switch: Connects several networked devices, but 'switches' the circuits, so that when one device transmits, the Switch 'switches' it's internal circuits so only the receiving device sees the data. No collisions or storms - much better than a hub.

Router: connects different networks so they can talk to each other. It routes traffic from (say) your home network to the Internet & back again.

Answer 2

Hub is the earlier version of the three, signals are broadcast to all client, the clients discarded the signals untill the real recipient received it.  in switch. the signal goes direct to the recipient client.

while a router does this work with additional security (firewall)

Answer 3

There are three different degrees of internet sharing involved with each:

Hub: This is the most basic and merely splits your internet connection into multiple ports so that it can be shared by multiple computers

Switch: This one is a little more complicated as it can also help more evenly distribute and share the bandwidth amongst the different ports for each computer.

Router: This one is the most advanced. This one has built in firewalls (usually) and can prevent attacks, and will also provide full speed bandwidth to each of the computers connected to it. This one is the only one with built in security features.  

Answer 4

To quote from the site I am linking...

"...A hub is typically the least expensive, least intelligent, and least complicated of the three. Its job is very simple: anything that comes in one port is sent out to the others. That's it. Every computer connected to the hub "sees" everything that every other computer on the hub sees. The hub itself is blissfully ignorant of the data being transmitted. For years, simple hubs have been quick and easy ways to connect computers in small networks.

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. For example, if it sees traffic from machine A coming in on port 2, it now knows that machine A is connected to that port and that traffic to machine A needs to only be sent to that port and not any of the others. The net result of using a switch over a hub is that most of the network traffic only goes where it needs to rather than to every port. On busy networks this can make the network significantly faster.

A router is the smartest and most complicated of the bunch. Routers come in all shapes and sizes from the small four-port broadband routers that are very popular right now to the large industrial strength devices that drive the internet itself. A simple way to think of a router is as a computer that can be programmed to understand, possibly manipulate, and route the data its being asked to handle. For example, broadband routers include the ability to "hide" computers behind a type of firewall which involves slightly modifying the packets of network traffic as they traverse the device. All routers include some kind of user interface for configuring how the router will treat traffic. The really large routers include the equivalent of a full-blown programming language to describe how they should operate as well as the ability to communicate with other routers to describe or determine the best way to get network traffic from point A to point B..."