Proof-of-Humanity

A primary application of Proof-of-Humanity is the distribution of a Universal Basic Income (UBI) token. Verified humans on the registry receive a regular, unconditional stream of currency, funded by a continuous token mint. This creates a crypto-native social safety net and explores economic models where identity, not capital, is the basis for distribution.

• Example: The Proof of Humanity protocol on Ethereum issues UBI tokens to registered participants.

PoH registries provide a foundational layer for one-person-one-vote governance systems in DAOs and protocols. By linking a single verified identity to a wallet, it prevents Sybil attacks where a single entity creates multiple fake identities to manipulate votes. This enables more democratic and legitimate quadratic funding and token-curated registries.

• Key Benefit: Replaces capital-weighted (token-based) voting with human-weighted voting for specific community decisions.

Proof-of-Humanity enables social recovery mechanisms for smart contract wallets (like Safe). Instead of relying on a single seed phrase, users can designate verified humans from their trusted network as guardians. These guardians can collectively help recover access to a wallet if keys are lost, creating a more resilient and user-owned security model.

• Mechanism: Integrates with EIP-4337 (Account Abstraction) to allow recovery via multi-sig approvals from verified identities.

Projects use PoH registries to conduct fair airdrops and community distributions that target unique individuals rather than wallets. This mitigates sybil farming where bots or whales create thousands of addresses to hoard tokens. Eligibility is based on proven humanness, ensuring a broader, more equitable distribution of new tokens to a genuine user base.

A verified PoH profile acts as a core Decentralized Identifier (DID). This reusable, sovereign identity can be linked to verifiable credentials for KYC, professional attestations, or reputation scores across different dApps. It creates a user-controlled alternative to centralized identity providers, forming the bedrock of a web3 social graph.

• Standard: Often implements W3C Decentralized Identifier standards.

The primary security goal of PoH is Sybil resistance, preventing a single entity from creating multiple fraudulent identities. It achieves this by linking a unique on-chain identity (like a profile or token) to a verified off-chain human through methods such as:

• Video verification and biometric liveness checks.
• Social graph vouching from existing trusted members.
• Government ID submission (often via zero-knowledge proofs for privacy). This creates a cost (social, reputational, or procedural) to identity creation that is prohibitive for large-scale attacks.

PoH systems often introduce trusted third parties or centralized arbiters, creating potential attack vectors:

• Verifier Centralization: A single entity (e.g., the verification provider) can become a bottleneck or censor.
• Governance Attacks: Control over the registry's upgrade mechanism could allow malicious changes to verification rules.
• Legal Coercion: Verifiers may be compelled by legal jurisdictions to deactivate specific identities. Decentralized or community-governed verification processes are used to mitigate these risks.

PoH registries are targets for identity theft and submission fraud. Key vulnerabilities include:

• Deepfakes & Spoofing: Using AI-generated media to bypass video verification.
• Document Forgery: Submitting falsified government IDs.
• Vouching Collusion: Groups conspiring to vouch for fake profiles. Countermeasures involve multi-modal verification, time delays, stake-based slashing for false vouches, and continuous monitoring for duplicate biometric data.

Verification requires submitting sensitive personal data (video, ID documents). The security of this data is paramount.

• On-Chain Exposure: Storing raw data on-chain is highly risky. Solutions use hash commitments or zero-knowledge proofs (ZKPs) to prove verification without revealing underlying data.
• Verifier Trust: Users must trust the verification entity not to misuse or leak their biometric data. Decentralized Identifiers (DIDs) and self-sovereign identity models aim to return control to the user.

PoH systems often incorporate economic stakes to secure the registry.

• Staked Deposits: Users lock collateral (e.g., ETH) that can be slashed if they are found to be fraudulent or act maliciously.
• Challenge Periods: New registrations enter a challenge period where anyone can dispute them by putting up a stake, triggering a decentralized dispute resolution (e.g., Kleros court).
• Exit Costs: The time and cost to create a new identity acts as a deterrent against cheap, disposable Sybils.

The core property that Proof-of-Humanity systems aim to achieve. Sybil resistance refers to a protocol's ability to withstand Sybil attacks, where a single entity creates many fake identities (Sybils) to gain disproportionate influence. PoH is a direct mechanism for achieving this by binding one identity to one human, which is critical for:

• On-chain governance (one-person-one-vote)
• Fair airdrop distribution
• Preventing spam in decentralized social networks

A W3C-standardized method for verifiable, self-sovereign identity that does not rely on a central registry. While a PoH registry can serve as a verifiable data registry for DIDs, they are distinct concepts.

• DID: A URI that points to a DID document containing public keys and service endpoints.
• PoH: A specific application or claim that can be attached to a DID to prove humanness. Together, they enable portable, privacy-preserving proofs of unique humanity across applications.

A security model for crypto wallets where a user's private keys or account access can be recovered through the consensus of a pre-approved group of guardians. Proof-of-Humanity enhances social recovery by ensuring guardians are verified unique humans, not Sybil accounts or anonymous keys. This makes the recovery process more robust and resistant to collusion or attack, as guardians are accountable, real-world entities.

A blockchain-based implementation of a regular, unconditional income distribution. The Proof-of-Humanity registry is foundational for crypto UBI projects, as it solves the fundamental problem of ensuring payments go to unique individuals. Verified humans on the registry can receive periodic token distributions (e.g., UBI tokens), creating a decentralized, global basic income system without centralized means-testing or duplication.

Non-transferable non-fungible tokens (NFTs) that represent credentials, affiliations, or commitments. A Proof-of-Humanity verification is a prime example of a foundational SBT—it is minted to a wallet, attests to a specific trait (unique humanity), and cannot be sold or transferred. Other SBTs, like educational diplomas or professional licenses, can build upon this base layer of verified identity.