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Signal

25
ResearchMountain View, United StatesEst. 2018
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About

Signal Messenger LLC, operated by the Signal Foundation, develops the open-source Signal end-to-end encrypted messaging protocol. The foundation was founded in 2018 by Moxie Marlinspike and Brian Acton. In September 2023, Signal upgraded its X3DH key agreement to PQXDH, which mixes the classical X25519 elliptic-curve handshake with the CRYSTALS-Kyber-1024 post-quantum KEM so that an attacker must break both to recover session keys. PQXDH became mandatory for new sessions across Signal clients in 2024. Signal has continued its post-quantum work with the SPQR (Sparse Post-Quantum Ratchet) extension, which brings post-quantum security to the message ratchet itself, aiming for full post-quantum forward secrecy throughout the session.

Quantum Specifications

Quantum Focushardware

Backed By

Lakestar
Lightspeed Venture Partners
Quantum Coast Capital
Type One Ventures
Trumpf Venture
Gic Government Of Singapore Investment Corporation
Hercules Capital
Inven Capital

Application Areas

Secure messagingOpen source cryptography

Frequently Asked Questions

Signal Messenger LLC, operated by the Signal Foundation, develops the open-source Signal end-to-end encrypted messaging protocol. The foundation was founded in 2018 by Moxie Marlinspike and Brian Acton. In September 2023, Signal upgraded its X3DH key agreement to PQXDH, which mixes the classical X25519 elliptic-curve handshake with the CRYSTALS-Kyber-1024 post-quantum KEM so that an attacker must break both to recover session keys. PQXDH became mandatory for new sessions across Signal client...
Signal is headquartered in Mountain View, United States.
Signal was founded in 2018.
Signal operates in the following sectors: post quantum cryptography, quantum security.