What Is a Router?
A router is a network device that forwards data packets between computer networks and carries out the traffic steering function on the Internet. Data sent over the internet, such as web pages or e-mails, is in the form of data packages. A packet is usually forwarded from one router to another through a network which is an internetwork until it reaches its destination node.
The router is connected to two or more data lines from different IP networks, and when a data packet enters one of the lines, it will read the network address information in the packet header to determine its final destination. Then, using information in the routing table or routing policy, it directs the packet to the next network on its journey.
Routers may have interfaces for various types of physical layer connections, such as copper cable, optical fiber, or wireless transmission. It also can support different network layer transmission standards. Each network interface is used to allow data packets to be forwarded from one transmission system to another. It can also be used to connect two or more logical groups of computer devices known as subnets, each with a different network prefix.
All sizes can be found within the company. The most powerful are usually found in ISPs, academic and research facilities. Large businesses may also need stronger ones to cope with the increasing demand for intranet data traffic. The hierarchical internetworking model for interconnections in large networks is commonly used.