What Does a Router Do?

A router is hardware device or software program that is designed to manage the paths along which information packets are forwarded within a network. Routers are necessary for communication between computers on your personal network and the Internet. This article will describe the manner in which a router manages this data transfer.

What Does a Router Do?


Understanding how the Internet works is key to understanding what a router does? The Internet is a huge, global network of computers, by means of which we browse through the World Wide Web. Data is transferred on the Internet via the TCP/IP networking protocol--a set of protocols that are designed to communicate data across the Internet. The data that is transmitted over the TCP/IP network is first split into fragments that are called "packets." This is where routers come in.


A router enables data communication between the computers on any given network and others that are on the Internet. The router is designed to direct or "route" data packets to their destination, which is where the term "router" is derived. Routers link the numerous computer networks that make up the Internet, and are responsible for determining the destination to which each data packet is forwarded to, as well as the best possible route it should take to get to that destination.


Cisco 7600 Series Router - Image coutesy of Akc9000, under the GNU license

Routers range in size from the huge models that manage the massive flow of data traffic between the various computer networks on the Internet, to the small, more common models that are available at the local computer store or from Internet Service Providers. They also range in function from the basic router/switch to the more intricate, multi-function routing devices. These smaller models are typically installed in home networks to make it possible for users to share a single Internet connection among two or more computers on the network.


There are two basic types of routers: static and dynamic. A static router needs to be manually configured by a network administrator, who programs all of the routes along which the router will forward data packets. A dynamic router comes programmed to automatically manage the routing of data traffic across the network, which is facilitated by a routing protocol.


Routers can be used to integrate essential services and utilities into the network, to make it more secure and responsive. Routers may, for example, integrate a security utility such as a firewall. They may also help increase network functionality by integrating services like IP voice or video capability.