Routers
Routers are generally known as intermediate systems, which operates at the network layer of the OSI reference model, routers are devices used to connect two or more networks (IP networks) to the Internet.
At the centre of the network is the router. Simply said, 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.
Routers are now being added to satellites in space. These routers will have the ability to route IP traffic between satellites in space in much the same way that packets are moved on Earth, thereby reducing delays and offering greater networking flexibility.
Advantages of a Router
In addition to packet forwarding, a router provides other services as well. To meet the demands on today's networks, routers are also used to:
Ensures steady, reliance availability of network connectivity. Routers use alternative parts in the case the primary part fails to the delivery of packets.
Routers provide integrated services of data, video, and voice over wired and wireless networks.
Of course the most important of all is security, this is where router helps in mitigating the impact of worms, viruses, and other attacks on the network by permitting or denying the forwarding of packets.
Router Connecting Two LANs
Router Connects LAN to Internet
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