What is the Internet?

Many people use the internet daily for various tasks without fully understanding what it is or how it works. Understanding how the Internet functions is important as it helps users make more informed decisions regarding online security and more

The Internet is a global network of interconnected computers that communicate using a standard set of protocols.

Originally called ARPANET (Advanced Research Project Agency), the Internet began in the 1960s as a project funded by the United States Department of Defense to decentralize communication and ensure survivability in the event of possible nuclear attacks. In the 1980s, the Internet evolved into a public infrastructure and gathered support from public universities and private companies. Today, it is used by billions of people around the world and is an essential part of modern life, providing access to information, facilitating communication, and more

The Internet is decentralized, meaning no one owns it. Instead, thousands of organizations operate their own networks and exchange traffic with each other based on voluntary interconnection agreements.

How data is sent

When you send data over the internet, it is broken into tiny pieces called packets sent from your device to a router. The router examines the packet and forwards it to the next router in the path towards its destination. This process continues until the packet reaches its final destination. Once the information reaches its destination the packets are reassembled into their original order

To ensure data is sent and received correctly, the Internet uses various protocols, including the Internet Protocol (IP) and the Transmission Control Protocol (TCP). IP is responsible for routing packets to their respective destination, while TCP ensures that packets are transmitted reliably and in the correct order.

Protocols

Protocols are defined set of rules or guidelines that dictate how devices and systems communicate and exchange information over the Internet. Some examples of protocols are TCP, IP, FTP, and HTTP, to name just a few.

Packets

Packets are small bits of data. Information on the Internet is transferred in the form of packets. These packets do not follow a fixed path; instead, they may take different routes depending on various factors, such as network congestion and availability. Breaking data into packets improves efficiency and network congestion.

Routers

Routers are devices responsible for directing data packets between different networks. They examine packets and forward them to the next router in their path until they reach their final destination. Every router has a unique IP address, just like a home address, which helps computers find each other.

IP Address

An IP address is a bunch of unique numbers assigned to each device connected to the Internet, similar to how homes have unique mailing addresses. IP addresses ensure that data, such as a video, is sent to the correct recipient and not someone else. Every device connected to the internet has an IP address

For example, an IP address might look like this:

174.129.14.120

Fortunately, you don't need to memorize IP addresses. Domain names make it easier for humans to access websites without remembering long strings of numbers.

DN

Computers can easily handle an IP address but humans would struggle to do so, especially as an IP address can change over time. To solve this problem, we use a domain name. A domain name is a unique, easy-to-remember address used to access websites, such as ‘google.com’. A system called Domain Name System (DNS) exists which associates domain names like ‘google.com’ to their corresponding IP address.

DNS

A Domain Name System (DNS) is a decentralized naming system that translates domain names to IP addresses. A single DNS server can't handle the multitude of devices looking to access any of the billions of websites. To address this, DNS servers are organised in a distributed hierarchy and are divided into zones, each responsible for the major domains such as; .org, .com, and so on. While DNS was originally created as a public system, its open nature made it susceptible to cyber attacks, necessitating security improvements over time.

HTTP and HTTPS

Hypertext Transfer Protocol (HTTP) is the protocol used to transfer data on the internet. HTTP requests are stateless, meaning each request is independent and does not retain information about previous interactions. Each request must contain all necessary data for the server to process it.

HTTPS (HTTP Secure) is the more secure version of HTTP that encrypts data transmitted between client and server. It protects the integrity of data being sent over the internet and ensures confidentiality. HTTPS uses SSL (Secure Sockets Layer) or TLS (Transport Layer Security) protocols to encrypt communications, safeguarding sensitive information from interception.

Parts of the Internet

The Internet consists of three main parts:

• The last mile: This is the segment of the internet that connects homes and small businesses to the internet.

• Data centres: These facilities house servers that store user data and host online applications and content. Some data centres are owned by large companies like Google and Facebook, while others are commercial facilities that provide services to multiple smaller websites.

• The backbone: The backbone consists of long-distance networks, primarily fibre optic cables, that transport data between data centres and end users across the globe.