How Does the Internet Works?

Everyone is talking about the internet and whether or how it should be regulated. But there are not enough people who know how the Internet really works, or what exactly the Internet is.

Next, I explain to you as clearly as possible how the Internet works and how the Internet connection is established, as well as who is involved in the network. The following explanation is for summary purposes and may also be geared towards children.

1. What Exactly is the Internet?

You probably have your own "local area network" in your home, and it is made up of all the devices connected to your router, which connects to the internet.

That's all the Internet really is: A host of computer networks around the world, connected to each other. Of course, there is a wealth of physical hardware, from cables under city streets, to massive cables on the ocean floor, to satellites orbiting the planet, which makes this communication possible.

There is also a lot of software running in the background, allowing you to type in a website address such as " Google.com " and have your computer send information to the physical location where that website is located in the fastest possible way.

2. Practical Example: Website

Even when you are connecting to a single website, there are many more things that happen. Your computer cannot directly send information, or "packet" of data, to the computer hosting the website. Instead, it passes the packet to your home router or router with information about where it is going and where the webserver should respond.

The router sends it to the routers of your Internet service provider (ISP), where it is sent to another router of another Internet service provider, and so on until it reaches its destination. All packets sent to your computer from the remote server go the reverse way.

To use an analogy, it's a bit like mailing a letter. Your (local) postal employee cannot simply take the letter and take it directly across the country or continent to your destination address. Instead, the letter goes to the local post office, where it is sent to another post office, and then to another, and so on, until it reaches its destination.

It takes more time for a letter to get to the other side of the world than to the other side of the country because it has to make more stops, and that is also true for the Internet. Packages will take a little longer to travel longer distances with more transfers, or " hops" as they are called.

Unlike physical mail, sending data packets is still very fast, occurring many times per second. All packets are very small and go back and forth when a large number of packets are sent when computers communicate. The travel time of a package is measured in milliseconds.

3. Data Can Go Many Ways

This network of networks is a little more interesting and complex than it seems. With all these networks connected, there is not a single data path. Because networks are connected to many other networks, there is a complete network of connections that spans the entire world. This means that those packets (small pieces of data sent between devices) can take multiple paths to reach their destination.

In other words, even if a network between you and a website fails, there is generally another route that the data can take. Routers along the route use something called the Border Gateway Protocol, or BGP, to communicate information about whether a network is down and what the optimal route is for the data to take.

Creating this interconnected network (or internet) is not as simple as connecting each network to a nearby one, one by one. Networks are connected in many different ways along many different routes, and the software running on these routers (so-called because they route traffic across the network) is always working to find the optimal routes to carry the data.

The Path that the Traceroute Packets Take

“Traceroute” is kind of a tool that helps you to find out the route that takes a data packet on the way to its destination. However, only devices are evaluated which evaluate the IP header of a data packet and are called “router” in-network jargon. If a data packet is transmitted based on the data link layer (e.g. via an Ethernet switch) or through a tunnel, devices on these network connections are not detected.

Nevertheless, “Traceroute” is a useful tool that supports both the Windows and the Linux operating system by default. This is useful because it gives you some insight into the external “Internet”, which helps you to troubleshoot problems, for example, if you think you have lost your connection to the Internet.

The basic the functioning of Traceroute is very simple and is based on the so-called Time To Live (TTL) field of the IP header data. This time to live field is reduced by 1 in every device that evaluates the IP header data of a data packet. If the value falls to 0, the data packet is deleted and a notification is sent to the source of the data packet using the ICMP protocol.

4. IP Addresses, DNS, TCP / IP, HTTP, and More Details

This is a big level overview of how the internet works. There are many small topics that are important to the Internet that we all use, and that you can read more about in detail.

IP Addresses

For example, each device on a network has a unique numerical IP address on that network. The data is sent to these addresses. There are IPv4 addresses (old) and IPv6 addresses (newer). The Full form of IP is Internet Protocol, that's why IP address is known as Internet Protocol Address These are the addresses used by devices on the network.

DNS

People use human-readable domain names like ccnadesdecero.es and Google.com, which are more memorable and understandable than a series of numbers. However, when you use domain names like these, your computer contacts the Domain Name System (DNS) server and asks for the numerical IP address for that domain.

Think of it as a great public address book for phone numbers. Businesses and individuals who want domain names have to pay to register them. You probably use the DNS service of your Internet service provider, but you can choose to use another DNS server such as Google Public DNS or Open DNS.

TCP / IP

Behind all this, there are different layers of "protocols" that devices use to communicate, even when using the Internet protocol. The most common transport protocol is TCP/ IP, which is called the Transmission Control Protocol over Internet Protocol. TCP is all about reliability, and devices converse and track data packets to make sure nothing is lost along the way. If it does, it is noticed and forwarded. There are also other protocols, such as UDP, that prioritize speed over reliability.

The previous transport protocols, such as TCP and UDP, are application protocols, such as HTTP or HTTPS - the Hypertext Transfer Protocol used by users in their web browser. The HTTP protocol works over the TCP protocol, which works over the IP protocol.

Other applications can use different protocols or create their own protocols that, however, operate on protocols such as TCP and IP. Much of the technology we use involves layers of technology built into other layers, and the same goes for the Internet.