Signal
Signal is a cross-platform encrypted messaging service developed by the Signal-Foundation and Signal-Messenger-LLC. It is widely considered the industry standard for secure communication due to its use of End-to-End-Encryption. The application is recommended by high-profile privacy advocates such as Edward-Snowden and Jack-Dorsey for its commitment to user anonymity and data protection.
The Signal Protocol
The foundation of the app's security is the Signal-Protocol, a cryptographic protocol that was previously known as the TextSecure Protocol. It combines the Double-Ratchet-Algorithm with a Triple Diffie-Hellman handshake. According to the Signal Technical Documentation, this ensures that every message has a unique key, providing perfect forward secrecy. This technology has been adopted by other platforms, including WhatsApp and Google-Messages.
History and Governance
The service was created by Moxie-Marlinspike, a security researcher who founded Whisper Systems. In 2018, Brian-Acton, the co-founder of WhatsApp, provided $50 million in funding to establish the Signal-Foundation as a non-profit organization. As reported by Wired, this move was intended to ensure that the development of Signal remains independent of corporate influence or advertising revenue.
Transparency and Open Source
One of the key advantages of Signal is that it is Open-Source-Software. The client and server code are publicly available for audit on the official Signal GitHub. This transparency allows the Cybersecurity community to verify that the software does not contain backdoors. Unlike many competitors, Signal collects minimal metadata, storing only the date of account creation and the last date of connection.