Wednesday, January 25, 2012

Difference between Hub, Switch, Router, Gateway & Bridge

I always confuse with the terms Hub, Switch & Router. Previously I have cleared the differences after searching in the Internet. After few days, again I forgot the differences. I am not involved in network related works. So this can be the reason behind forgetting the differences again & again. Thus this time I have decided to write it down in my blog so that I can find it anytime.

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.

Switch :
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.

Initially, a switch knows nothing and simply sends on incoming messages to all ports. Even accepting that first message, however, the switch has learned something - it knows on which connection the sender of the message is located. Thus, when machine "A" responds to the message, the switches only need to send that message out to the one connection.

Switches learn the location of the devices that they are connected to almost instantaneously. The net result is that most network traffic only goes where it needs to rather than to every port. On busy networks, this can make the network significantly faster.

Router is the smartest and most complicated of the bunch. Routers come in all shapes and sizes.A simple way to think of a router is as a computer that can be programmed to understand, possibly manipulate, and route the data that it's being asked to handle. Many routers today are, in fact, little computers dedicated to the task of routing network traffic.

A combination of hardware and software to link two different types of networks. This usually involves converting different protocols. For example, a gateway could be used to convert a TCP/IP packet to a NetWare IPX packet.

A combination of hardware and software to link two similar networks. It often connects LANs that use the same protocol, such as Ethernet. A bridge examines each data packet on a LAN and forwards any data packets addressed to a connected LAN. Bridges are faster than routers because they connect networks that are using the same protocol.