Zax - secure messaging between you and your Guardians

Why are security, resilience, and decentralization of communication important?

The internet is like nature, both beautiful and diverse, but also dangerous at times. This is even more true in the young and still-wild blockchain and Web3 ecosystems. To achieve security and resilience, it is necessary to decentralize resources, encrypt all communications, and assume zero trust in service providers. Ideally, services can be self-sufficiently run by participating users alone, without any centralized servers acting as intermediary. These goals of security, resilience, and decentralization are pursued by honest and long-term participants in the industry. That's why the Vault12 team designed the "Guard" app to implement communications between Owner and Guardians in such a way that all users communicate independently without any centralized server. There is no risk of interception.

What are Zax intermediaries?

Even when intermediaries -- called Zax relays -- assist in message synchronization during device offline periods, they are only blind relays. These intermediaries may store encrypted messages from users until the recipient comes online. However, these relays have zero knowledge of the message contents or recipients. They act as temporary inboxes blindly and with no awareness of the message content.

Moreover, users can easily run their own private Zax relays to maximize independence and security. The source code of the relay is available on GitHub for everyone.

How strong is the Zax protocol?

The protocol's design incorporates multiple cutting-edge solutions to achieve top-notch resiliency:

1. Communication ratchet - This simple yet extremely powerful principle ensures that each individual message between Vault and Guardians is encrypted with a brand new private key, making it impossible for long-term, sophisticated, and expensive key attacks to succeed.
2. Proof-of-Work - Like Bitcoin's core innovation of the proof-of-work principle, we also adopted it for decentralized messaging: Zax relays implement a Proof-of-Work defense against potential DDoS (Denial of Service) attacks. This ensures that the service is consistently available.