Building Blocks

On a high level, there are several building blocks that are required for an effective PoP mechanism. Those include “deduplication” to ensure everyone can only verify once, “authentication” to ensure only the legitimate owner of the proof of personhood credential can use it and “recovery” in case of lost or compromised credentials. This section discusses those building blocks on a high level.

A proof of personhood mechanism consists of three different actors and the data that they exchange.

For the context of this section, these terms are defined as follows:

• User: An individual seeking to prove specific claims about herself in order to access certain resources or more generally qualify for certain actions. Within the context of a PoP protocol those claims are related to proving uniqueness and personhood.

• Credential: A collection of data that serves as proof for particular attributes of the user that indicate the user is a human being. This could be a range of things, from the possession of a valid government ID to being verified as human and unique through biometrics.

• Issuer: An trusted entity that affirms certain information about the user and grants them a PoP credential, which enables the user to prove their claims to others.

• Verifier: An entity that examines a user's PoP credential and checks its authenticity as part of a verification process to grant the user access to certain actions.

Certain interactions between users, issuers and verifiers, like deduplication, recovery and authentication are important building blocks for a functional PoP mechanism. This section gives a high level overview of the building blocks of a general PoP mechanism. Detailed explanations on how those are implemented with ChainX ID follow in later sections.