Welcome
At this documentation you will learn about our architecture and the APIs that can be combined or utilized as stand-alone solution in order to complete a successful flow in the encryption and decryption of the Zero Knowledge Face Proof (ZelfProof), first of its kind to be commercialized to the public.
What is Zelf?
Zelf is a cutting-edge privacy-preserving biometric verification system that revolutionizes identity management by utilizing advanced cryptographic techniques to ensure security without storing or exposing any biometric data. It uses face data to generate a unique, non-biometric binary representation called ZelfProof, which facilitates highly secure authentication, encryption, and verification processes.
Unlike traditional biometric systems that store templates and are subject to breaches or misuse, Zelf ensures that no biometric data is ever retained, making it a fully privacy-preserving solution designed for the next generation of identity verification, proof of personhood, and secure access control.
Join our Discord to request access to the API. https://discord.gg/49JnBAsaq9
Key Features
No Biometric Storage: Biometric data is not stored. Instead, we use facial recognition to generate an encrypted, randomized, privacy-preserving, non-biometric binary representation – which is your ZelfProof.
Liveness Detection: Our system can verify the end user's presence, preventing spoofing attempts and ensuring that only the legitimate user can access the wallet.
Offline Capability: Zelf works both online and offline, requiring no internet connection to function.
Easy Storage: Instead of storing the private information on the cloud, cold storage or written in a piece of paper, users can now store it in a QR Code(which contains the ZelfProof) and save it on IPFS as an optional storage that will help the user to do a safe and decentralized backup, and later decrypt it by presenting a the user's face + the password (optional).
How Does Zelf works?
Zelf is built on a foundation of privacy-preserving cryptography. Here’s an in-depth look at the process:
1. Registration (Encrypting)
Face & Metadata Capture: The user provides a live face scan along with optional sensitive information like your private key of your wallet, name, ID numbers, or other identifying information.
Zelf Processing: The captured face data is used as an input to generate a private key through proprietary cryptographic algorithms. Importantly, the face data is not stored or used beyond this, ensuring compliance with privacy regulations. The system simply utilizes the face as a one-time private key for generating a ZelfProof.
ZelfProof Processing: A ZelfProof, which is a privacy-preserving, non-biometric binary structure, is generated. Unlike a biometric template, ZelfProof is:
Encrypted
Unique to each session
Biometrically verifiable but non-biometric in nature
Unique ZelfProof: A new ZelfProof is created every time you authenticate with your face, password (optional), and any metadata. Each ZelfProof is unique to that session and cannot be reused or intercepted.
No Reuse Risk: Even if someone captures your face and password, without the correct ZelfProof for that session, they cannot authenticate. Similarly, without the right face or password, an old or different ZelfProof will not work.
2. Verification (Decrypting)
Live Face Scan: During verification, the user performs a live face scan. This scan is not stored but is used as a cryptographic key to initiate the verification process. It’s important to note that the system doesn’t compare the face to any stored biometric data. Instead, the face scan acts as a dynamic input to regenerate the cryptographic structure (ZelfProof) that was created during registration.
ZelfProof Matching: The ZelfProof generated during registration (when the user initially encrypted their data using their face) is dynamically recreated during verification. However, since the ZelfProof is non-biometric and unique to each session, the system does not retrieve or store the user's face data. It merely checks that the cryptographic structure matches the one generated during the session without retaining biometric information.
Decryption of Private Information: If the regenerated ZelfProof from the live scan matches the encrypted structure, any optional sensitive information (such as wallet keys, ID numbers, etc.) that was secured during registration is decrypted. This allows the user access to their credentials or services without exposing their biometric data at any point.
Final Verification: The system validates the integrity of the ZelfProof by checking the cryptographic signature against the trusted public key. If all checks pass, the user’s identity is verified, granting them access or confirming their credentials.
Key Properties of a ZelfProof
Revocable: ZelfProofs are revocable on the online version. This means that if a user's identity needs to be updated or revoked, a new ZelfProof can be generated from the same face and metadata, but with a different cryptographic key, effectively rendering the previous one invalid.
Offline & Distributed: The verification process can be done offline, making Zelf suitable for decentralized systems, distributed ledgers, and scenarios where internet access is limited or unavailable. Verification can occur without the need to access a centralized database, preserving privacy and enhancing security.
Multi-Use Credentials: A single face scan and metadata set can be used to generate multiple ZelfProofs, allowing different ZelfQR for different applications, such as:
Government ID
Corporate Access Cards
Proof of Personhood for decentralized applications (dApps)
Wallet encryptions
Zero-Trust Architecture: The system operates under a zero-trust model, meaning that neither the verifier nor any intermediary ever gains access to the user’s biometric data or identity attributes during the authentication process.
Advantages of Zelf and the ZelfProofs
1. No Biometric Data Storage
Traditional biometric systems store templates that are vulnerable to theft or misuse. Zelf ensures that no biometric data is ever stored or retrievable, eliminating compliance risks and enhancing user trust.
Since no biometric data is stored, there’s no risk of that data being hacked, leaked, or misused. The biometric input is used only during the session and discarded immediately after.
2. Revocability
Unlike traditional biometric templates, which cannot be revoked or regenerated, ZelfProof are revocable and renewable. If a ZelfProof is compromised, a new one can be generated, and the old one invalidated—making Zelf adaptable and future-proof.
3. Unlinkable
Each ZelfProof is inherently unlinkable, meaning that even if a user generates multiple ZelfProofs across different services, they cannot be linked back to a single identity, protecting user anonymity and privacy.
4. Offline & Distributed
Zelf supports fully offline verification, ideal for use in decentralized, offline, or low-connectivity environments. It can serve as a self-sovereign identity solution, where users maintain control over their credentials without relying on third-party servers or databases.
5. Enhanced Privacy & Compliance
Zelf complies with the strictest data privacy regulations, such as GDPR, by ensuring that no personally identifiable information (PII) or biometric data is ever exposed. This significantly reduces the regulatory burden on organizations that adopt Zelf.
Jump right in
Last updated