If you’re reading this article, you are one of more than 5.1 billion people who have access to the internet (according to internetworldstats). For many around the world, access to the internet is not a luxury but a necessity, providing them a means of livelihood, education, social interaction, etc. It’s therefore strange that many of the internet’s most consistent users who use it for critical purposes don’t know how the technology works.
What Is The Internet?
The internet is a worldwide system of computer networks that are wirelessly connected. The internet is a network of networks because it is decentralized and consists of various kinds of networks– public, private, government, academic, and so on– linked by different devices. The internet is a means of transmitting various types of services and resources to other users globally.
History Of The Internet
The earliest work on the design of what we now call the internet began in the early 1970s with the development led by Vinton Cerf and Bob Kahn. The original experiment they were working on was called ARPANET (Advanced Research Projects Agency Network), a research project sponsored by the United States Defense Department.
The primary motivation behind the ARPANET research was to build a decentralized network system. The pursuit of a decentralized network stemmed from the ongoing Cold War and the risk of a nuclear attack from Eastern bloc forces. Creating a centralized network would have made that location a target of Soviet forces; the Defense Department wanted to create a network that an attack could not shut down.
In the early 1960s, a Polish-American engineer known as Paul Baran had developed a means of grouping data into packets– which contained a header and a payload– over a digital network. His work was later popularized in 1965 by Welsh computer scientist Donald Davies who coined the term packet switching; this was the basis on which they formed the new decentralized network. The Defense Department built an experimental nationwide packet network, and it worked.
The primary use of the internet in the 1980s was for academic purposes, and the modern-day model of internet usage that covers every aspect of modern life began in the 1990s. Enterprises and commercial networks linking themselves to the internet facilitated the switch, leading to a massive leap in popularity that has continued to date.
A Breakdown Of How The Internet Works
Below is a breakdown of how the internet works into short sections for easy understanding:
1. Servers And Data Centers
The internet consists of various types of computers that perform various functions; a category of computers vital to the internet’s operation is a server. Servers are computers dedicated to providing or serving users on the internet with data that service providers save or host on their storage. Servers are not fancy computers like the ones we use for office work and gaming; instead, they are machines built to endure long running hours and optimize efficiency.
Data centers are entire buildings dedicated to housing multiple servers. Most servers and data centers host files from multiple users and service providers; however, big companies like Facebook and Google use up entire data centers.
2. The Internet Backbone
Data centers can send and receive requests and responses from users around the globe via a complex optical fiber network known as the Internet Backbone. The Internet Backbone is a connection of optical fiber cables that transmit light pulses carrying packets of data to various parts of the world. Large companies have to lay these cables underneath the earth and beneath the sea over significant distances for the internet to work.
For wired connections, cables connect your router to the Internet Backbone; and finally, you can receive the data on your computer via ethernet cables. Cell towers facilitate wireless connections; they work by receiving data via optical cables from the Internet Backbone and transmitting that data as electromagnetic waves to wireless devices like phones and laptops.
3. Efficiency Via Data Packets
The internet can achieve high efficiency and low latency by breaking down large files into little bits known as packets, each consisting of a sequence number. These packets are routed to users via the best available paths and automatically reassembled on your device according to their sequence number. Some packets might get lost on their way to your device; in this case, your device will resend a request to the server to try and get that lost packet.
4. Protocols To Bring Order
As explained above, the flow of data packets is a highly complex process; as with other types of network connections, protocols are essential to bringing order to the system. These protocols set the rules for transferring and converting data packets between the data centers, routers, and user devices. Protocols also attach the source and destination addresses to each packet.
Different applications and services use various types of protocols; some of the common ones are:
- HyperText Transfer Protocol / Secured (HTTP/HTTPS) for web browsing.
- File Transfer Protocol (FTP) for the sending and receiving of files.
- Simple Mail Transfer Protocol (SMTP), the Post Office Protocol (POP), and the Internet Message Access Protocol (IMAP) for email services.
- Real-time Transport Protocol (RTP) for video and audio streams.
5. Addressing And Recognizing Devices
Every device connected to the internet has an Internet Protocol Address– commonly known as an IP Address; this address is a string of numbers that uniquely identifies that device on the internet. An IP Address prevents data requests and responses from being misplaced among the billions of interconnected devices.
IP Addresses are assigned to devices by Internet Service Providers (ISPs). These ISPs are companies that provide users with access to the internet; they are the ones who own the huge cell towers that convert optical data into wireless electromagnetic signals. Your ISPs are also the companies that sell access to the internet via various data subscription plans.
6. Domain Names For Ease Of Access
Since all websites and other forms of data are stored on servers, and every server has an IP Address, you can access these websites via their IP Addresses. However, remembering multiple IP Addresses is a difficult task that is made easy by using domain names. Domain names are strings used to identify a particular IP Address; examples are facebook.com, youtube.com, clouddevelop.org, etc.
Accessing a website via its IP Address is only possible in a few cases because servers usually host more than one website. When multiple websites are on a server, things like request headers finetune the request.