Reusable identity

Verify once, then reuse that verified identity elsewhere without starting over.

For example, a person who verified their identity with a bank can prove the same identity to a rental service with a single tap, and the second service never asks them to photograph an ID again.

A portable, cryptographically bound identity credential that can be presented to multiple relying parties after a single proofing event. A relying party is any service that accepts the credential instead of running its own identity check.

A reusable identity typically works in four steps:

1. The person completes identity proofing once with a trusted issuer.
2. The issuer provides a credential, which the person stores in a digital identity wallet or similar app.
3. When the person needs to prove who they are to a new service, they approve sharing the credential or the specific details the service requests.
4. The service checks the credential's cryptographic signature to confirm that a trusted issuer created it and that nobody has altered it.

Issuers come from different places:

• Governments issue digital IDs, such as mobile driver's licenses and national digital identity wallets.
• Private organizations, such as banks and identity providers, issue credentials after their own proofing process.

Reusable identity sits next to terms that are easy to mix up:

• Single sign-on (SSO) proves that a person controls an existing account, while reusable identity carries verified facts about who the person is.
• Digital identity wallet is the app that holds credentials, while reusable identity describes the idea of verifying once and reusing the result.
• Verifiable credential is the signed digital document format that often carries the reusable identity.