Why is end-to-end encryption essential in the digital age?

The security of your communication depends on the encryption method.

Imagine that every message you send travels through several layers of security to reach the recipient. Without proper protection, it could be read by those who manage the servers between you. That is why more and more people are turning to end-to-end encryption – a technique that ensures that only you and your contact have access to your communication.

End-to-end encryption (E2EE) is not a new concept. Back in the 1990s, Phil Zimmerman created Pretty Good Privacy (PGP), a program that demonstrated the power of cryptographic protection. Today, this idea has evolved into modern protocols that you use in applications like WhatsApp, Signal, or Google Duo.

How do usual (unencrypted) communication channels work?

When you send a message in a traditional messenger, your phone sends it to a central server. The server sees who it is intended for and forwards it to the appropriate recipient. At first glance, it seems simple, but the reality is more complex.

Although data is sent between your device and the server using TLS (Transport Layer Security), which is a security protocol that prevents interception during transmission. However, the server between you and the recipient has the key to read all messages. This means that the service provider can see the content of your communication. If hackers could access their database, your intimate conversations could become publicly available – as has already happened in dozens of massive data breaches.

The Principle of End-to-End Encryption: How is Your Message Actually Protected?

End-to-end encryption works on a simple principle: the server that transmits the message does not read it at all. Instead, your data is encrypted in such a way that only the intended recipient can decrypt it.

For it to work, you first need to create a shared secret with your partner – a process known as key exchange. The most famous method is the Diffie-Hellman key exchange, devised by cryptographers Whitfield Diffie, Martin Hellman, and Ralph Merkle.

How does key exchange work?

Imagine two participants, Alice and Bob, who want to create a secure channel over an insecure network - for example, over the Internet filled with potential spies.

Both will first agree on a common starting value - as if they were exchanging a public artifact that anyone can see. In our example, we will imagine it as a shared golden color. They receive it and return to their private rooms.

In private, everyone adds their secret shade - Alice mixes in blue, while Bob adds red. No one else sees these secret colors. Then they exchange the resulting mixtures in a public place. Alice receives Bob's blue-green-yellow mixture, and Bob gets Alice's red-green-yellow.

When everyone mixes in their secret shade again:

• Alice combines her blue with Bob's mixture
• Bob will combine his red with Alice's mixture

Both resulting colors will be identical – only those two know how to create it. The spies only saw the public mixtures, not the secret components.

The real mathematics on which the system is built is much more complex and cryptographically unbreakable.

They can then send encrypted messages.

Once the parties have a shared secret, they can use it for symmetric encryption. Modern applications add additional security layers, but the user is unaware of this. Encryption and decryption occur only on your devices.

Once you connect with a friend in an E2EE app, the communication is protected. Whether it's text, photos, files, or video calls – everything is encrypted. If someone - whether a hacker, provider, or state agent - intercepted the message, they would only see gibberish.

Real Risks: What E2EE Does Not Address

Although end-to-end encryption provides strong protection during transmission, there are still other threats:

Threat to your device: If someone takes your phone or installs malicious software on it, they can see messages before they are encrypted or after decryption. Encryption protects data in transit, not at the endpoints.

Attack “man in the middle”: During a key exchange, someone could deceive you. Instead of connecting with your friend, you might create a secret with the attacker. They could then read and modify your messages.

To prevent this, many applications include security codes – strings of numbers or QR codes that you can verify through a secure channel ( ideally in person or through an already verified channel ).

Why choose end-to-end encryption?

Despite the mentioned risks, E2EE is indispensable for privacy protection. Digital freedom activists around the world promote it precisely because it reduces the risk of misuse of your data.

The largest technology companies are experiencing cyber attacks. Information about users - sensitive communications, identity documents - is falling into the hands of those with malicious intent. If the company used E2EE, attackers would only gain metadata ( information about who is communicating with whom, but not the content ). While this still raises privacy concerns, it is fundamentally better than access to the messages themselves.

Range of Available End-to-End Encrypted Tools

End-to-end encryption is no longer just for tech enthusiasts. iOS and Android operating systems have integrated features - Apple iMessage and Google Duo. More and more software emphasizes privacy and security.

End-to-end encryption is not a universal solution against all cyber threats. But with minimal effort, you can actively use it and significantly reduce the risks you are exposed to online. Along with the Tor network, VPNs, and other digital security tools, end-to-end encryption becomes an indispensable part of your privacy protection.