 | What is a router? |
Technical Answer:
A router is a device that that forwards data packets between networks. Routers are placed at the intersections of networks, called gateways. The router examines the destination IP address of packets passing through it and determines where to send it. This decision is based upon data stored internally in the router's routing tables and network layer information. Advanced routers may also analyze the packets and take action based upon their contents. This action is commonly referred to as firewalling.
On a home network, the packets are often being passed between one or more PC's and an ISP, which connects to the internet. The internet itself is mostly composed of routers, and data packets may pass through over 20 routers on their way from source to destination. Each pass between routers is recorded in the packet itself. When the packet finally does get to the destination machine, a return packet is sent to acknowledge the receipt. However, if the destination machine is unreachable (it may be switched off, or undergoing maintenance), or the packet has passed through too many routers (usually because of a routing administration error), an error message is reported to the source machine.
The ISP assigns the router a public, routable, and globally-unique IP address. The router assigns each computer on the home network it's own private IP address. As only the IP address of the router is public, outside computers can only communicate directly with the router. This shields the computers behind the router from intrusion and exploitation. Anti-virus and anti-spam filters may also be in place on the router, substituting these unwanted packets with information regarding their contents. The filtering software is user-configurable and must be updated often.
Short Answer:
A router is a small box that connects several comp...
Long Answer:
A router is an external hardware component that connects several computers to each other and to a...