A rebuttal to Arnold and Longley’s article Daniel Hardman, March 2020 CONTENTS Abstract Setting Expectations Rebuttal 1. The article defines “zero-knowledge proofs” too narrowly, setting up a basic fallacy. 2. It exaggerates and quotes experts out of context to build a straw man model of anonymity. 3. It oversimplifies the basis of trust. 4. It...Read More

In a previous post, I described how verifiable credentials differ in their approach to privacy: Correlating credentials correlate their holder to a disclosed identifier, and a disclosed signature, that’s the same in every use of a given credential. Other attributes are often identical as well, but these two perfect correlators are guaranteed to be present...Read More

In my previous post, I explained how issuers, holders, and verifiers of verifiable credentials (VCs) work together to unlock new business value with self-sovereign identity (SSI). I also contrasted verifiable credentials with other digital credential approaches. Now I’d like to go a bit deeper. Within the ocean of verifiable credentials, what variety exists? What motivates...Read More

What Are Verifiable Credentials? The tangible credentials we all use—driver’s licenses, passports, birth certificates, car titles, and plane tickets, for example—are now being re-imagined as digital files. We can carry these digital credentials on smartphones, index and search them, back them up, and make perfect copies of them on demand. But while digital records are...Read More

We all know that identity matters. We hear about cybersecurity breaches, GDPR, refugees, deep fakes, and election fraud. Each headline highlights a new way that identity impacts us. Yet we may be accepting naive assertions about what identity actually means. Some equate identity with authentication. Others map it to accounts and credentials. Still others think...Read More