"End-to-end encrypted" is written everywhere — but what does it mean technically? And why does VOID talk about Olm and Megolm? This article explains it in plain terms.
What end-to-end encryption means
With true end-to-end encryption (E2E), messages are encrypted on your device and only decrypted again on the recipient's device. In between — including on the server — only ciphertext is visible. Not even the operator can read along.
The Matrix protocol
VOID is built on Matrix, an open, standardized communication protocol. For encryption, Matrix uses two complementary methods:
Olm — for one-on-one chats
Olm secures 1:1 communication. It builds on the proven Double Ratchet principle: fresh keys are derived for practically every message. If a key is compromised, earlier and later messages stay protected anyway (forward secrecy).
Megolm — for group chats
Megolm is optimized for groups. Instead of encrypting each message separately for every member, it uses an efficient, continuously rotating group key — secure and performant, even with many participants.
Why encryption alone is not enough
E2E protects the content — not necessarily the metadata (who, when, how often). This is exactly where VOID goes beyond encryption alone:
- Only its own server, no federation with third-party Matrix servers.
- No logging of connection or access data beyond what is technically essential.
- No phone number — access runs through an activation code.
Conclusion
Olm for one-on-one, Megolm for group chats: Matrix offers modern, open encryption at a high level. Together with its own no-logging server, that makes VOID a messenger that takes both content and metadata seriously.