Router is a Microprocessor controlled device that forwards data packets across the computer network. It is used to connect two or more data lines from different net works. Function of the router is the traffic direction in the network. The most common router is the home router used to transfer small data packets like web pages, e-mails etc between the DSL modem and the Computer. Routers may be Enterprise routers transferring datas in business or ISP networks or Core routers that transfer data through optical fiber network.