Tag: signal

  • Re: The Ecosystem is Moving

    Moxie Marlinspike gave a talk at 36C3 that misrepresented decentralized systems. This is my opinion regarding his arguments.

  • Closer Look at the Double Ratchet

    In this post I try to explain the Double Ratchet Algorithm that drives the cryptography behind OMEMO and Signal. This is the second part of my series about the crypto behind OMEMO.

  • Shaking Hands With OMEMO: X3DH Key Exchange

    In this blog post I take a detailed look at how the Extended Triple Diffie-Hellman Key Exchange (X3DH) works. This algorithm is part of the cryptography that drives OMEMO.


    Recently there was a lot of news coverage of an alleged „backdoor“ in WhatsApp, the proprietary messaging application owned by Facebook. WhatsApp deployed OpenWhisperSystem’s Signal-protocol roughly a year ago. Now a researcher showed, that WhatsApp’s servers are able to register a new device key for a user, so that messages that the user did not…