Chapter 1: Introduction
What Is FayID
FayID is the unified identity infrastructure of the iFay ecosystem. It provides a consistent set of identification, binding, and authentication-exchange mechanisms for every participant in the ecosystem — real natural persons, digital personas they create, public-facing shared roles, and organizational entities alike.
In one line: FayID gives every participant in the iFay ecosystem an identity that is verifiable, traceable, and privacy-preserving.
Four Kinds of Subjects
The FayID system is organized around four kinds of core subjects:
| Subject | Description |
|---|---|
| Human Prototype | A real person in the physical world. Each human prototype holds a unique Human ID as their root identity, backed up via a Mnemonic. |
| Digital Persona (iFay) | An AI persona that a natural person creates within the iFay ecosystem. One person can own multiple iFays; each iFay carries its own iFay ID, but every iFay is bound back to the same Human ID. |
| Public Role (coFay) | A public-facing shared role that may be created and owned by an individual or an organization. Each coFay has its own coFay ID and Verification Code. |
| Organization | A company, team, or other legal entity. An Organization ID is published in plaintext and does not require Dynamic Code protection. |
The ownership and binding relationships among these four kinds of subjects form the skeleton of the FayID system — see Chapter 3 Entities and Relationships for details.
Why FayID Is Needed
On the traditional internet, a single person often has to maintain a large number of independent accounts, passwords, certificates, and tokens for different systems. FayID's design is motivated by three core needs:
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One person, one identity, many tickets aggregated: a natural person holds a single Human ID and can exchange it for any number of traditional authentication tickets (passwords, certificates, access tokens, smart contracts, etc.) without having to remember each one.
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Root identity privacy: the Human ID is the root identity and must never appear in public communication. External interactions use a time-limited Dynamic Code instead, which rotates automatically when it expires; Dynamic Codes generated at different times cannot be correlated with each other.
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A foundation for the Global Merit Chain: FayID is the identity layer of the iFay ecosystem's long-term reputation system, the Global Merit Chain. Reputation records must accumulate over time without ever exposing a natural person's root identity — FayID resolves this tension through an irreversible reference, the opaqueRef.
The Long-Term Vision: Global Merit Chain
The Global Merit Chain is the long-term vision of the iFay ecosystem: a decentralized reputation-record system that accumulates over time. In this system:
- iFay IDs, coFay IDs, and Organization IDs serve as plaintext subject identifiers for reputation records and are visible on-chain.
- A natural person's reputation is associated indirectly through an irreversible reference, preserving reputation continuity while protecting the root identity.
- The identification, ownership, and revocation primitives provided by FayID are prerequisites for the Global Merit Chain to function.
FayID is not the Global Merit Chain itself; it is the foundational identity layer beneath it. Without a stable, verifiable, privacy-preserving identity system, reputation records have nothing to anchor to.
How to Read This Blueprint
This blueprint is organized into separate chapter files. For a first read, we recommend the following order:
- Glossary (Chapter 2): establish a shared vocabulary
- Entities and Relationships (Chapter 3): understand ownership and binding among the four kinds of subjects
- Credentials and Lifecycle (Chapter 4): learn how Dynamic Codes, Verification Codes, and Authorization Grants are created and expire
- Auth Exchange (Chapter 5): see how FayID replaces traditional authentication
- Privacy and the GMC Interface (Chapter 6): understand the privacy hard constraints and the on-chain interface boundary
- Open Questions (Chapter 7): review the open problems that the current protocol layer leaves undecided
Each chapter can be read on its own, but a first end-to-end read helps build a complete mental model.