Glossary
Credentials
A set of one or more claims made by an issuer.
Source: W3C Verifiable Credential Data Model
Cryptographic Suite
A set of cryptographic algorithms and protocols used to secure data and communications. In the context of verifiable credentials, cryptographic suites ensure the integrity, authenticity, and confidentiality of data.
Decentralized Identifiers (DIDs)
A portable URL-based identifier associated with an entity. DIDs are commonly used in verifiable credentials to ensure they can be easily moved from one repository to another without needing to be reissued. Example: did:example:123456abcdef.
Source: W3C Verifiable Credential Data Model
DID Methods
DIDs are not created and maintained in a single type of database or network like many other types of URIs. There is no authoritative centralized registry — or a hierarchy of federated registries like DNS — where all DIDs are written and read. Many different types of DIDs exist in today’s SSI community. They all support the same basic functionality, but they differ in how that functionality is implemented, e.g. how exactly a DID is created or where and how a DID’s associated DID document is stored and retrieved.
These different types of DIDs are known as DID methods. The second part of the DID identifier format — between the first and second colons — is called the DID method name.
Example of DIDs created using five different DID methods:
did:sov:WRfXPg8dantKVubE3HX8pw— Sovrin (sov).did:btcr:xz35-jzv2-qqs2-gwjt— Bitcoin (btcr).did:v1:test:nym:3AEJTDMS×DDOpyUftiuoeZ2Bazp4Bswilce7FJGYbcUu— Veres One (v1).did:ethr:OXE6Fe788d8ca214A080b0f6aC7F48480b2AEfa9a6— Ethereum (ethr).did:jolo:1fb352353f51248C5104b407f9c04c3666627fcf5a167d693c9fc84675964e2— Jolocom (jolo).
Source: Self-Sovereign Identity: Decentralized digital identity and verifiable credentials
DIDComm Messaging
A secure messaging protocol designed for exchanging verifiable credentials and other cryptographic data in a privacy-respecting manner. DIDComm ensures the secure and private communication between entities in the SSI ecosystem.
Entity
A person, organization, device, or other identifiable actor with a distinct and independent existence that performs one or more roles in the digital identity ecosystem.
Source: W3C Verifiable Credential Data Model
Holder
An entity that possesses one or more verifiable credentials and generates presentations from them. Holders typically store their credentials in digital wallets or credential repositories.
Source: W3C Verifiable Credential Data Model
Issuer
A role an entity can perform by asserting claims about one or more subjects, creating a verifiable credential from these claims, and transmitting the verifiable credential to a holder.
Source: W3C Verifiable Credential Data Model
JSON Schema
A declarative language used to annotate and validate JSON documents, ensuring that they conform to a specified structure.
Source: Verifiable Credentials JSON Schema Specification
Self-Sovereign Identity (SSI)
Self-sovereign identity — commonly abbreviated SSI — is a new model for digital identity on the internet: i.e., how we prove who we are to the websites, services, and apps with which we need to establish trusted relationships to access or protect private information.
Source: Self-Sovereign Identity: Decentralized digital identity and verifiable credentials
User-Defined Types (UDT)
Custom data models created by users to define specific credential schemas. UDTs simplify credential lifecycle management by providing enhanced type safety and reducing the likelihood of errors during creation, issuance, and validation.
Verifiable Credentials (VCs)
A tamper-evident credential containing a set of claims made by an issuer, which can be cryptographically verified to ensure authenticity and integrity.
Source: W3C Verifiable Credential Data Model
Verifiable Credential JSON Schema
A JSON Schema used for validating W3C Verifiable Credentials. The schema is contained within the verifiable credential itself.
Source: Verifiable Credentials JSON Schema Specification
Verifiable Presentations (VPs)
Data derived from one or more verifiable credentials, issued by one or more issuers, that is shared with a specific verifier. A verifiable presentation is a tamper-evident presentation encoded in such a way that authorship of the data can be trusted after a process of cryptographic verification. Certain types of verifiable presentations might contain data that is synthesized from, but do not contain, the original verifiable credentials (for example, zero-knowledge proofs).
Source: W3C Verifiable Credential Data Model
Verifier
A role an entity performs by receiving one or more verifiable credentials, optionally inside a verifiable presentation for processing. Other specifications might refer to this concept as a relying party.
Source: W3C Verifiable Credential Data Model
Wallet
A program or application that stores, manages, and protects access to holders' verifiable credentials. Digital wallets allow users to control their digital identities and selectively share information with verifiers.