The difference from ordinary encryption#
With ordinary encryption, the connection between you and the server is encrypted, but the server itself sees and stores the message. With end-to-end encryption, the message is encrypted on the sender's phone and opened only on the recipient's phone. The server only moves unreadable data.
Why does it matter?#
Even if the service provider is hacked, or someone gains access to its servers, the content of the messages is unreadable. That means privacy is preserved even against the service itself.
Example#
WhatsApp uses this method for ordinary conversations. Telegram does not do so by default in regular chats and groups, and only its "secret chats" are end-to-end encrypted. So when choosing a messenger, you should pay attention to the type of protection, not just its appearance.
Limitations#
- E2EE doesn't protect your device. If the phone is infected or in someone else's hands, the messages can be read.
- A cloud backup may keep a copy without end-to-end protection.
- Metadata, such as who messaged whom and when, may be recorded.
- It doesn't stop the recipient from taking screenshots or forwarding.
What should we do?#
- Turn on the screen lock and the messenger's two-step verification.
- Check your backup settings.
- For sensitive conversations, use a messenger that has this feature by default and accept the encryption.