Self-Sovereign Identity (SSI)

Self-Sovereign Identity (SSI) is a concept where individuals are empowered to own, control and manage their digital identities without an intervening authority. An SSI platform can be implemented by using the blockchain technology as an identity trust fabric. 

Verifiable Presentation (VP)

A verifiable presentation is a presentation of a verifiable credential, which is tamper-evident and can be cryptographically verified. A verifiable presentation is created by a holder and verified by a verifier. 


A holder is a role of an entity that holds a verifiable credential, created by an issuer. A holder can present her verifiable credential in the form of a verifiable presentation to a verifier. 

Hash Function

A cryptographic hash function is a one-way function for converting a digital message into a seemingly random bit array of a fixed size. For a given hash value, it is infeasible to reverse-engineer the hash function and obtain its original message, called the hash preimage.  

Digital Signature

A digital signature is a cryptographic scheme for verifying authenticity of digital messages and documents. A digital document that is cryptographically signed is tamper-evident. In asymmetric cryptography, a private key is used for signed a document whereas a public key is used for verifying the document. 


A blockchain is a list of immutable records, called blocks, that are cryptographically linked. Each block contains a cryptographic hash of the previous block. Integrity of the whole blockchain can be verified by iteratively verifying the hash values all the way back to the original genesis block. A blockchain that is distributed over a network […]

Identity Management (IM)

An identity management (IM) is a framework of policies and technologies for ensuring that the people in an enterprise have appropriate accesses to resources. 

Hardware Security Module (HSM)

A hardware security module (HSM) is a physical computing for managing and safeguarding cryptographic keys. A HSM contains a secure storage for cryptographic keys and crypto-processor chips for executing cryptographic operations such as key generation and digital signature. 

Public Key Infrastructure (PKI)

A public key infrastructure (PKI) is a system for managing cryptographic public keys. A PKI system includes hardware, software, policies and roles, such as a certificate authority, for creating, managing distributing, storing and revoking public key certificates. A public key infrastructure that is built on a distributed ledger is called a decentralized public key infrastructure […]

Zero-Knowledge Proof (ZKP)

A zero-knowledge proof (ZKP) is a cryptographic protocol by which one party (called the prover) can prove to another party (the verifier) that she knows something without revealing its underlying information or content. One application of a ZKP is selective disclosure for minimal revealing information in a credential. 

New : 2020 Guidance for Decentralized Identity and Verifiable Claims

Get the guide