Why should you care about end-to-end encryption?

The Scary Truth About Your Messages

Imagine that every message you write to your friends goes through an intermediary server before reaching them. This server – let's say the app company – can read everything you write. It may not do so now, but it has the capability. And if the database is breached (, which happens constantly ), millions of messages are at risk.

This is where end-to-end encryption comes into play as a solution that truly makes your messages secure – so that no one can read them except for you and the original sender.

How did unencrypted messages work?

When you write a message in a regular app, it goes directly to a central server. This server knows your identity and the recipient's. It carries the message and delivers it. The problem? The server reads everything.

Yes, there may be an encryption layer between your device and the server (, like TLS), but once the message reaches the server, it becomes exposed. It can be stored in a database containing billions of other messages. And if someone hacks it? A disaster.

End-to-end encryption: the real solution

End-to-end encryption means one thing only: You and the recipient are the only ones who can read the messages. The server, the service provider, even the government – no one can.

Popular applications like WhatsApp, Signal, and Google Duo use this technology. The message is sent encrypted, and the key is only present on your device and the recipient's device.

The Real Magic: The Diffie-Hellman Key Exchange

How do both parties succeed in creating a secret key without having previously informed each other about it?

Imagine Alice and Bob in a hotel. They want to exchange a secret paint color without the spies seeing.

First, they agree on a common color in public – yellow. Each takes a little.

Then, in his private room, he adds Alice her secret color (blue), mixing yellow and blue. Bob does the same with his color (red), resulting in yellow, blue, and red.

They exchange the mixture in public. The spies see them, but they cannot discern the secret colors.

Now Alice takes the Bob mix and adds her secret blue color. Bob takes the Alice mix and adds his red color.

And the surprise: Both end with the same final mix – blue, yellow, and red. This is the common secret!

Spies have never seen the secret colors. This is the principle of perfect encryption between the parties.

Undeniable Advantages

✓ No one reads your messages – not even the messaging app

✓ Protection from breaches – If the database is breached, the messages are just random codes.

✓ Easy to use – You don't need to know anything about encryption technically.

✓ Available for Everyone – iMessage and Duo are already integrated into your phone

Real Challenges

No, end-to-end encryption is not perfect:

1. Man-in-the-Middle Attack (Man-in-the-Middle) If you are exchanging the key with someone, are you really sure it is them? You could be talking to a hacker and not even know it. To avoid this, use verification codes – strings of numbers or QR codes that you can verify through another secure channel.

2. Your device may be at risk Even if the messages are encrypted in transit, if someone gains access to your phone or personal device, they can read the messages. Or if you have malware.

3. Do not protect metadata The sender, the recipient, the time – all this information can be revealed. It is not as important as the content of the message, but it makes a difference.

4. Political Conflict Some governments want a “backdoor” to access messages. This completely undermines the idea.

Important Point: Encryption Alone Is Not Enough

End-to-end encryption protects messages while they are in transit. But there are other threats:

• Hacking your device directly
• Malware that spies before and after transmission
• Intermediate attacks at the beginning of the connection
• Metadata leakage

Therefore, end-to-end encryption is part of a larger strategy – complemented by Tor, virtual private networks (VPN), and secure security behaviors.

Summary

End-to-end encryption is not a magic trick, but it is a very powerful tool. In a world where breaches have become commonplace and companies store millions of messages, the ability to send a message that only the intended recipient can read – that is real value.

Some applications that you already use, such as iMessage, Signal, and WhatsApp, utilize this system. In the future, end-to-end encryption will become the standard, not the exception.