What is a Router

Network Routers Explained

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A router is a device used in computer networks to connect networks that are dissimilar and that work on different protocols. For example, you are likely to find a router connecting a LAN and a WAN; for instance your private local area network to the Internet. You often get routers from Internet service providers, since these allow you to connect your computer or home network to the telephone line.

This is the definition of routers that most people know.

On a more technical note, a router has a very important role in the mechanism of the Internet and in IP networks in general. It has a central part in IP networks. 

Each router on a network forwards data packets traveling on that network towards their destinations, based on their IP addresses. The work a router does it called routing, which is somewhat like switching, but a router is different from a switch. The latter is simply a device to connect machines to form a LAN.

How a Router Works

When data packets are transmitted over a network (say the Internet), they move through many routers (because they pass through many networks) in their journey from the source machine to the destination machine. Routers work with IP packets, meaning that it works at the level of the IP protocol.

Each router keeps information about its neighbors (other routers in the same or other networks).

This information includes the IP address and the cost, which is in terms of time, delay and other network considerations. This information is kept in a routing table, found in all routers.

When a packet of data arrives at a router, its header information is analyzed by the router. Based on the destination and source IP addresses of the packet, the router decides which neighbor it will forward it to.

It chooses the route with the least cost and forwards the packet to the first router on that route. This happens at each router until the data packet reaches its destination. 

Wireless Routers 

A wireless router is one which connects to devices wirelessly. Most routers act as a hub as well, in the sense that they connect devices to a LAN. Wireless routers have a WiFi module and most have a small antenna allowing them to connect to devices. 

If you want to access your router, type 192.168.1.1 in the address bar of your browser. If prompted for login information, enter admin for both the username and the password. 

Do I Need a Router?

If you have a LAN and want to connect it to the Internet, then you need a router. If you are deploying VoIP on your LAN, then you need one. If you have a simple phone system, then choose an ATA. But as mentioned above, most of us use routers without realizing and we are offered routers to connect to the networks of ISPs.