BLK105 · Digital Identity and Verifiable Credentials

Go deep into decentralized identifiers, the W3C Verifiable Credentials Data Model 2.0, selective disclosure and revocation, and design a privacy-respecting credential flow for a real business need.

Advance · 8 hours · 4 lessons, a lab, an assessed assignment and a portfolio piece

Who it is for

Solution architects, developers, compliance and HR professionals and product owners working on identity, onboarding or document verification.

Prerequisites

BLK102 (keys and signatures); BLK103 is helpful but not required.

What you will be able to do

• Compare centralized, federated and self-sovereign identity models and their trust assumptions
• Explain how DIDs, DID documents and verifiable credentials work together in the issuer, holder and verifier model
• Issue, present and verify a signed credential in a notebook, including a revocation check
• Design a credential flow that applies data minimization, selective disclosure and privacy-law requirements

Lessons

• Lesson 1 · Identity models and decentralized identifiers
• Lesson 2 · Verifiable credentials and presentations
• Lesson 3 · Privacy, selective disclosure and governance
• Lesson 4 · Lab and assignment

Lab: Issue and verify a training-completion credential

You create an Ed25519 key pair for a fictional issuer and express it as a did:key identifier. You issue a credential following the VC Data Model 2.0 structure, signed as a JWT, then verify it as an employer would. Finally, you simulate a status list and show how the verifier detects that a credential has been revoked.

Free tools: Google Colab (free) with Python, the cryptography library and PyJWT

Assessed assignment

Design a verifiable-credential solution for one scenario: contractor safety training for a construction company, proof of age at a retail store, or student-discount eligibility for a gym chain. Produce a flow diagram of issuer, holder and verifier, the exact claims in the credential and which are disclosed in each presentation. Explain the DID method, signature format, revocation approach and wallet choice. Include a privacy analysis covering data minimization, consent, retention and the applicable privacy law, and attach your lab notebook.

Portfolio piece

A verifiable-credential solution design with a flow diagram, privacy analysis and a working issuance and verification notebook.

Self-paced, 12-month access. Questions are answered in writing through the student panel. A completion record is issued when you finish the course.