Moxie Marlinspike’s Crypto Protocol

Nowadays, since people life starts to rely their life on computers and internet, significance of encryption has been rise with it. Andy Greenberg, the author of the article “Meet Moxie Marlinspike, the anarchist bring encryption to all of us”, brought up with great achievement that has been never showed up in human history, which was unbreakable algorithm. Main character for this unbelievable invention, almost can be considered as a fairytale, was Moxie Marlinspike.

To introduce about Moxie Marlinespike, he is computer security engineer, who is widely known for Open whisper systems, Whisper Systems, Convergence (SSL), and Double Ratchet Algorithm. For his career, his focus point of his research paper was primarily on techniques for intercepting communication infrastructure against interception. He is also known as member of the Institute for Disruptive Studies, former head of the security team at Twitter, founder of Open Whisper system, and a fellow at the Shuttleworth Foundation. With such those outstanding career, however, his “Crypto Protocol, Signal” makes him much more remarkable.

To explain about his exceptional algorithm, it can be break down into 4 steps.

First, when Alice installs an app that uses Marlinspike’s “Crypto Protocol”, it will generates pairs of numeric sequences, which is known as keys. With each pair, one sequence, known as public key, will be sent to the app’s server and shared with her contacts. The other, known as private key, is stored on Alice’s phone and is never shared with anyone. The first pair of keys serves as an identity for Alice and never changes. Subsequent pairs will be generated with each message or voice call, and these temporary keys won’t be saved.

Then, when Alice contacts her Friend Bob, the app combines their public and private keys – both their identity keys and the temporary ones generated for a new message or voice call – to create a secret shared key. The shared key is then used to encrypt and decrypt their message or calls.
Next, the secret shared key changes with each message or call, and old shared keys aren’t stored. That means an eavesdropper who is recording their messages can’t decrypt their older communications even if that spy hacks one of their devices. (Alice and Bob should also periodically delete their message history.)

Lastly, in order to make sure that she is communicating with Bob and not an imposter, Alice can check Bob’s fingerprint, a shortened version of his public identity key. If that key changes either because someone is impersonating Bob in a so-called man in-the-middle attack or simply because he reinstalled the app, Alice’s app will display a warning.

With such creative and effective software, people around the World now can feel safe using Social Network Service’s messaging system. Furthermore, since those invention of amazing defensive system has been known to netizens, a lot of SNS programs, such as Facebook, Twitter, or Instagram start to use it.