Exploring Self-Sovereign Identity Through a Digital Transcript Proof-of-Concept

Credential forgery presents a significant threat to the integrity of academic and employment documents. While Self-Sovereign Identity (SSI) and Verifiable Credentials (VC) offer a decentralized alternative, existing solutions often struggle to balance institutional trust with holder privacy. This paper proposes a novel, dual-layered architectural framework for digital transcripts. We implement a strategic bimodal DID approach, utilizing did:web for the issuing institution to leverage established web reputation and did:key for the student holder to ensure lightweight, stateless mobility. Furthermore, we address privacy vulnerabilities in credential status checks by developing a k-anonymous Revocation List. This mechanism protects students by grouping 40,000 individual records into a single compressed bitstring (k = 40,000), ensuring that a specific student’s status cannot be uniquely identified or singled out during a check. Benchmarking results confirm the system’s efficiency, with core local cryptographic verifications executing in under 1 ms. We identify that system latency is primarily driven by network dependent interactions, specifically the time required for API-based credential retrieval and sending presentations to verifiers. Comprehensive functionality and security tests validate that this integrated approach successfully enhances credential integrity while maintaining superior user privacy compared to standard decentralized models.