Routers

Routers

Routers serve as the hub for packets to get sent to individual IP addresses on a network. In the OSI model, routers operate in the Layer 3, Network, while it operates in the Internet layer of TCP/IP. 

When packets enter the router, the router looks at each packet to send it to the correct IP address destination. This is done via a routing table. A routing table consists of four columns: Destination LAN IP, Subnet Mask, Gateway, and Interface.

The Destination LAN IP is the IP address of the device running on the network. This is where the incoming packet with eventually be sent. 

A Subnet Mask is set of numbers that will always equal 32 bits. The Subnet Mask is designed to help determine if the receiving device is on particular network.

The Gateway is in charge of sending the packets to the correct IP. If the receiving IP isn't connected to the router, the Gateway will give the IP address to the correct router.

And finally, the Interface column is simply there to help determine which port, LAN or WAN, is to be used.