w3tester on Nostr: A DID is a unique identifier of an entity. This identifier is generated by ...

A DID is a unique identifier of an entity. This identifier is generated by cryptographic method, just like a Nostr key, and you hold the private key. So you can say it is self-sovereign because only you ave control over this DID. In reality, this identifier is linked to a series of keys for you to use in different scenarios.