Intr. with R. & S. Lec_1

Introduction to Routing and Packet Forwarding

At the center of the network is the router. Stated simply, a router connects one network to another network. Therefore, the router is responsible for the delivery of packets across different networks. The destination of the IP packet might be a web server in another country or an e-mail server on the local area network. It is the responsibility of the routers to deliver those packets in a timely manner. The effectiveness of internetwork communications depends, to a large degree, on the ability of routers to forward packets in the most efficient way possible.

In addition to packet forwarding, a router provides other services:
1- (Availability), Routers use alternate paths in case the primary path fails.
2- Provide integrated services of data, video, and voice over wired and wireless networks. Routers use Quality of service (QoS) prioritization of IP packets to ensure that real-time traffic, such as voice, video and critical data are not dropped or delayed.
3- Mitigate the impact of worms, viruses, and other attacks on the network by permitting or denying the forwarding of packets.