What is a router and how does it work?

The router, at least the common home network device that we usually call routers, is the network hardware that allows communication between the local home network, such as personal computers and other connected devices, and the Internet.

The router used in home and small networks is more specifically called a residential gateway, but you will never see it that way.

What is a router used for?

A router is the first line of intrusion security in a network. Enabling the highest level of security on the router activates things like the firewall and is the best way to protect your computer system and information from attacks.

Routers contain software called firmware which must be updated as published by the router manufacturer.

Most routers connect to other network devices only via network cables and do not require running drivers on Windows or other operating systems. However, routers that connect to a computer via a USB or FireWire port typically require that the drivers work properly.

Routers often act as DHCP servers in small networks, issuing unique IP addresses.

Most routers are made by companies like Linksys, 3Com, Belkin, D-Link, Motorola, TRENDnet and Cisco, but there are many more.

How routers work

Routers connect a modem (such as fiber, cable or DSL modem) to other devices to allow communication between these devices and the Internet. Most routers, even wireless routers, usually have multiple network ports to connect multiple devices to the Internet simultaneously.

A router usually connects physically, via a network cable, to the modem via the Internet or to the WAN port, and then physically, always via a network cable, to the network interface the card in all the wired network devices you own. A Wireless Router for Business can connect via various wireless standards to devices that also support the particular standard used.

The IP address assigned to the WAN or Internet connection is a public IP address. The IP address assigned to the LAN or to the connection to the local network is a private IP address. The private IP address assigned to a router is generally the default gateway for various devices on the network.

Wireless routers and wired routers with multiple connections also act as simple network switches that allows devices to communicate with each other. For example, you can configure multiple computers connected to a router to share printers and files with each other.

Routers are like small computers, so there are a processor and memory to handle incoming and outgoing data. Different software, such as DD-WRT, can be loaded on the router just like an operating system on a computer.

A router operates on the network layer (layer 3) of the OSI model and uses the routing tables to understand where the traffic is coming from and where it should go.

Manage a router

Most likely there will come a time when you need to change the way the network works. This is done by accessing the software on the router.

You will need to connect to the router, if you want to change the router connection password, encrypt the network, configure port forwarding rules, change the Wi-Fi password, choose a different wireless network name or update the firmware on the router.

Some other common tasks related to managing a router involve restarting the router and fully restoring the router software.