How does the Internet work?
It would seem that laptops and search engines have appeared recently, but we can already put a computer in our pocket! How does the Internet work – a technology that allows you to carry a library, a music center or a dozen games with you? We talk about what a domain, server, router and other complex phenomena are in simple language!
The availability of computers and the ability to use the World Wide Web have become the greatest phenomena in the life of modern man. Thanks to them, everything has become more efficient: we can work more productively and have better rest. In the office, we look for business ideas, information on financial matters, and so on. At home, we watch movies or listen to music. Yet how did the Internet appear and what is its work based on?
What is the World Wide Web?
In short, this is a system that connects a huge number of computers in different countries and is built on the basis of a database of IP addresses. Simply put, these are computers assembled on the same network using a remote connection. They can transmit information remotely. By computer in this case we mean any device capable of transmitting signals. Thanks to
4G and 5G, these include mobiles, tablets, TVs, and sometimes even home appliances.
If you dig deeper, then you should think about what is the storage and transmission of information? Now by this they mean the communication of people on the network and the exchange of news. In addition, this is the use of cloud storage, buying and selling something. Therefore, the World Wide Web is a unified device that exchanges and stores information.
History of the Internet
The first mention of the creation of the Internet appears in 1962, in the work "The Galactic Network" by Joseph Licklider, where he describes the idea of the World Wide Web. American engineer Paul Baran at about the same time suggests in one of his reports that it is possible to create a confidential system of peer-to-peer devices interconnected.
This was the time of the Cold War, and the idea attracted attention because it was possible to be able to control the troops even at the start of a nuclear war. Money was allocated for technology research, and a few years later Larry Roberts proposed creating an internal network, connecting the computers of organizations with each other. This was done by the Universities of California, the Stanford Institute, the University of Utah. A cable was laid between them, and by 1969 the most important technical problems had been solved.
In the future, other scientists joined the development of the network project. After 2 years, the first e-mail appeared, and a few years later a transatlantic cable was laid. In the 1970s, computers were used to exchange letters, receive news, and view ads.
In the meantime, there is a need to develop universal protocols according to certain standards: IP, TCP, FTP, etc. appear. In the 1980s, when the use of the IP protocol expands, the term “Internet" appears. By 1989, Tim Berners Lee, a nuclear researcher, formulates and proposes the concept of the World Wide Web: HTTP, HTML, and URI appear. By 1993, the NCSA browser was developed, making the Internet convenient. The number of users is growing,
providers are appearing, the network is becoming the main way to exchange information.
How does the network work?
In fact, the principles of the Internet are very simple, and it differs from other networks for the most part only in scale. The World Wide Web consists of communication channels connecting a client, a server, and network devices. The client is a device that can request network information and provide it in an understandable way, the server is the storage medium that stores it in a database format that provides information to the client.
Network devices connect the client and the server. The scheme looks like this: the client sends a request to the server, it arrives through the network equipment. Therefore, the server processes it and finds the answer, sending it, using the same network equipment, to the client.
Network devices, that is, modems, switches, routers, and other communication channels must work continuously. First, the modem converts data from analog to digital and vice versa. Second, the router stores addresses and packets of information. Thirdly, the switch allows you to transfer data over the cable.
What are network nodes?
Devices that are part of a network and interconnected are called nodes. They can be both universal, such as computers or telephones, and special, such as routers.
The web server, that is, the software and the computer on which it is installed, processes HTTP requests and responses from clients that may contain HTML, that is, files, pictures, and any other data. The server recodes domains into IP addresses, stores network data, and so on. The client, that is, a web browser and the device on which it runs, sends requests to the server to obtain URLs that indicate the desired resources. The exchange between them takes place using the HTTP protocol.
Routers i.e. routers
These are devices that send data between different network segments, using established rules. It paves the way from, for example, a computer, to the site that the user wants to see. Without a router, it would be impossible to combine networks with different structures and protocols.
A data transfer protocol is an interface convention. First, they define a system for exchanging data between different software. Secondly, they create a unified algorithm for messaging and error correction when programs installed on different devices connected by a network interface come into contact.
Accordingly, the algorithms that make it possible to connect devices and exchange data are called network protocols. Modern protocols are defined by the IETF, that is, the international community of developers. The most common classification divides protocols into levels:
- Physical, characterizing the properties of the communication line
- Channel, which determines the algorithm for using the first level by network nodes
- Network and transport layers that regulate the addressing and delivery of information
- Session, managing the operation of device software
- The presentation layer that converts the data into a readable format
- Application, creating a boundary between application software and other levels.
All seven layers make the network work. Today, among the main protocols are IP and FTP, HTTP and SMTP, etc.
Every second, many devices connect to the network, and each of them needs to be defined somehow. Each device connected to the Internet has its own unique IP address, which includes both the domain address and the address of the host itself. The network ID is assigned when registering a domain. In addition, there is also a node address, which is assigned by the person who manages the operation of the domain.
Such a digital record is convenient for equipment, but is not perceived by people, so domains are assigned names written in letters. So, for example, the domain “doroga.com” may have an ip-address “123.33.305.69” and vice versa.
In addition, programmers often use the concept of a domain zone, that is, a zone of responsibility in the DNS system – the domain name system. DNS is, simply put, a system of devices united according to some criteria. It can contain one or many devices. Let’s say that one server is enough to create one small site, but many more devices are called the yandex.ru domain.
The domain system is based on a clear hierarchy and allows the structure of the Internet. There are three levels of domains, and 1st level domains are divided into geographic (ru, us), administrative (com, gov), thematic (today, bar).
DNS servers i.e. domain name service
Great, we know the address of the resource, it remains only to find it. It is worth saying that the difficulty is that one device will not be able to store such volumes of information. Therefore, DNS servers are used for lookups. They are located in different parts of the world and control different parts of the network. As a result, when a domain is created on one of its servers, a catalog of corresponding IP addresses is developed.
The device with it is a DNS server, the main task of which is to provide address information upon a client request. If the desired address cannot be found immediately, the server sends a request to its counterparts, and this continues until the address is found. This usually happens within a few seconds.
This happens so quickly because every resource on the Internet is also assigned a unique file location locator, a URL. It consists of the name of the protocol by which you can access the data, the address of the server, the name of the file on the server.
What is HTML language?
Based on the data that we already have, we can roughly understand the information exchange system. However, how do we get an answer that we can perceive?
Tim Berners-Lee, whom we talked about at the beginning, also developed the HTML language, which is used by browsers such as Google Chrome or Opera. As a result, it is a language created according to certain standards for marking up Internet documents. Thus, most of the pages have an HTML version.
We briefly described how the Internet works. Of course, there are more complex algorithms that are responsible for speed, information ranking, blocking, etc., but this is a much broader topic.