Network routers are essential devices in computer networking that serve as the central point of between different networks. They operate at the (Layer 3) of the TCP/IP networking model and are responsible for routing data packets between networks based on the source and destination IP address of the packet, enabling data to travel between devices on different or even across the internet. Home network routers are usually combined devices that also include a firewall, Ethernet switch, and wireless access point.
Routers are responsible for forwarding data packets between networks. When a router receives a packet, it examines the IP address and makes routing decisions to determine the most efficient path for the packet to reach its destination. Routing is the core function of a router. Routers use routing tables and algorithms to determine the best path for data packets to travel. They maintain these routing tables, which contain information about destinations and associated next-hop routers or interfaces. Routers also enable communication between devices on different networks or by routing data packets based on destination IP addresses.
A routing table contains information about network routes and is used to determine the best path for forwarding data packets from the source to the destination within a network. When a router receives a data packet from a connected device, it examines the packet's destination IP address. The router looks up the destination IP address in its routing table. If a matching route is found, the router determines the next hop or gateway to which the data packet should be sent, as well as the outgoing interface. If no specific matching route is found, the router may use a default route to send the packet to a default .
