Long-Lived Verifiable Credentials: Ensuring Durability Beyond the Issuer's Lifetime
Ricardo Bochnia, Jürgen Anke · 2024
Using Self-Sovereign Identity (SSI) and Verifiable Credentials (VCs) to digitize physical credentials is gaining momentum. In particular, credentials such as diplomas may need to remain valid for decades, sometimes outliving their issuers. For instance, a university diploma remains valid even if the issuing university merges or dissolves. We are therefore exploring the challenges that Long-Lived Verifiable Credentials (LLVCs) face in maintaining their value and verifiability over the long term. Although verifiers do not directly contact issuers when verifying a VC, they may still rely on an existing issuer, e.g., to verify the credential’s revocation state maintained by the issuer. If the issuer dissolves, the SSI trust triangle is broken, and the VC may lose its value, requiring approaches to preserve the longevity of LLVCs. To address the challenges of long-lived credentials, we analyze the management and requirements of physical education credentials as a prime example of long-lived physical credentials, leveraging them as a model for designing LLVCs. Our findings suggest combining approaches to design LLVCs to address their unique challenges effectively. Beyond technical approaches, our research also highlights the need for sustainable governance structures that extend beyond the life of the issuer to ensure that LLVCs achieve durability comparable to their physical counterparts.