The evolution of the Internet has profoundly changed the world, technology and people and it is difficult to imagine a life without being online. The device that makes all this possible is called Router, that small box connected to the wall socket, with several doors and lights on it, which allows all devices to connect to the Internet at the same time.
Without it, you wouldn't be able to surf the internet, you wouldn't be able to stream videos, or even connect to Facebook.
There is also a router for mobile mobile connections, even if this is not at home but in the control units of the network suppliers.
In this purely theoretical article we try to explain how a Router really works "> How to access the router
The Hardware
The first system that worked as a router is the gateway to ARPANET, the embryo of the modern internet from several years ago.
This router was a huge machine like a refrigerator.
The most common routers today can be held in hand, cost a few tens of Euros and are made up of a processor, RAM and flash memory and ethernet ports.
They are so simple that without being a computer wizard, it would be possible to take an old computer and convert it into a router without difficulty.
All routers have a WAN (Wide Area Network) port which is the wired connection that connects the router to the wall via cable.
Then, there is a large number of local area network ( LAN) ports for local area connections to connect everything to the network.
If there is an antenna (it may not be there) the router also has wireless wireless connectivity, which often transmits at 2.4 ghz and 5 ghz radio frequencies to connect all devices without interference ("dual-band" router ).
To activate a router, usually, you just need to connect all the necessary cables and turn it on.
In general, as written in a router configuration guide, you can access the control panel by entering its IP address in the browser (the number assigned for the Internet connection which usually begins with "192.168").
This may change depending on the router model and you need to consult the user manual.
How does it work?
The principle behind the operation of a router is quite simple: taking information from the cable or DSL through a WAN connection (which then comes from the internet), the router directs the information to the various connected devices making sure that all data is transmitted correctly .
The router is able to individually assign local IPs to all computers and simultaneously create a separate road for each system connected to the Internet.
All this to say that the router allows you to connect multiple devices to an ADSL modem .
In addition to translating data and routing connections, the router is also capable of functioning as a firewall, preventing unsolicited internet traffic from entering connected devices.
You can think of the router as the first line of defense of the network, which discards data that does not appear to be directed to one of the connected computers.
Practically discards unsolicited data thus preventing that there may be unauthorized external intrusions.
Although routers are not very different on how they get and transmit data, they are not all the same, at least when looking at wireless routers .
Wireless routers operate on two separate protocols, 802.11g and 802.11n which is faster.
This difference means that a computer with an 802.11g wifi card cannot connect to a router with 802.11n protocol.
Typically, 802.11n routers also work with 802.11g network cards although they will transmit slower without taking advantage of their best technology.
How do you connect to the Internet?
When we talk about computer networks, generally (not necessarily) we mean a group of devices connected to the same router.
They are connected to each other via the router which in turn is connected to the modem or cable to allow computers to go on the internet.
The Modem is the device that communicates with the Internet and receives / assigns an IP address belonging to the WAN network.
The various computers, passing through the router, come out on the internet as if they were a single entity, with the same network address or IP address, which is assigned by the provider and is different from the LAN network addresses that the router itself assigns to the various computer.
The WAN network is therefore separated, also for security reasons, from the LAN, the one that connects the home computers together.
The Internet is nothing more than the global WAN and, although they often tend to coincide in words, it is different from the World Wide Web which is only one of the Internet services.
The way a router actually communicates with a DSL modem to provide the Internet is an interesting concept that can be explained in an abstract way.
First of all it is important to know that every piece of information that passes on the Internet is actually called a " package ".
For example, when you open a web page, the computer sends a data packet and in return receives another packet that loads the requested information.
These packets go through a series of communication protocols and you can read about this in the article: " How do computers talk to each other on the network via TCP / IP? "
Routers play a key role in transmitting these packets, because they act as a sorting switchboard for each packet they send and receive.
All routers connected to the internet communicate with each other through the IP system to ensure that data is taken and returned to the right nodes (for example, from my computer to Google's servers when I do a search).
Given its importance, I recommend reading the guide on which wifi router to buy for the wireless home network
