DIDs & verifiable credentials
Cryptographically checkable claims — a nursing licence or a SIDHI certificate any employer can verify in seconds without calling anyone.
In one line
A DID is an identifier you control via cryptographic keys (no central registrar); a verifiable credential (VC) is a signed claim — "this person holds this qualification" — that anyone can check mathematically against the issuer's keys.
How it works
An issuer (university, council, platform) signs a credential bound to the holder's identifier. The holder stores it in a wallet and presents it — wholly or selectively ("over 18" without the birthdate) — to a verifier, who checks the signature and revocation status without contacting the issuer. Open Badges 3.0 aligns education credentials with this model.
Where it shows up in digital health
Clinician licence verification across states and borders; tamper-proof training certificates; health-data sharing consents as signed artefacts; vaccination certificates (India's DIVOC-issued COVID certificates were verifiable credentials at national scale). This platform's SIDHI certificates are planned as VCs from day one — decided in ADR 0010 precisely because credential formats are painful to retrofit.