Decentralized Identifier (DID)

A Decentralized Identifier (DID) is a class of identifier that lets a person, organization, or device prove control of a digital identity without relying on a central registry, an identity provider, or a certificate authority. A DID is just a string, such as did:key:z6Mk..., that resolves to a DID document describing the public keys and service endpoints needed to interact with the subject. Because the holder generates and keeps the corresponding private keys, the identifier is owned outright rather than rented from a platform. DIDs v1.0 became a W3C Recommendation in 2022, giving the model a formal standard.

Why it matters for sovereignty

Conventional logins are federated: Google, Apple, or a national ID system vouches for you — and can therefore revoke you, surveil you, or disappear with your accounts attached. A DID inverts that relationship. You can publish an identifier anchored to a blockchain, hosted on a domain you control, distributed over a peer-to-peer network, or derived purely from a key pair, and anyone can verify your control of it by checking a signature against the DID document. No platform sits between you and the proof. The custody discipline transfers directly from Bitcoin: the same care a Bitcoiner applies to a seed phrase applies to DID keys — lose them without a rotation path and you lose the identity; leak them and someone else is you. Key management is not a footnote to self-sovereign identity; it is the whole substance of it.

Methods and resolution

The portion after did: names a method that defines how identifiers of that type are created, resolved, updated, and deactivated. The methods span a spectrum of trade-offs. did:key is the minimal case — the identifier literally encodes the public key, requiring no infrastructure at all but allowing no key rotation. did:web anchors the DID document to a domain you control, cheap and human-legible but only as sovereign as your DNS. Ledger-anchored methods such as did:ion (which batches operations into Bitcoin transactions) buy censorship-resistant history at the cost of infrastructure. Resolving a DID returns its current document, and because the document can be updated, you can rotate keys without changing the public identifier — the property that separates a durable identity from a bare key pair.

Verification in practice is refreshingly simple: a verifier resolves the DID, reads the public keys from the document, and challenges the holder to sign a fresh nonce — a valid signature proves control, with no account, password, or identity provider anywhere in the loop. The document can list different keys for different purposes: authentication keys for logging in, assertion keys for signing credentials, key-agreement keys for encrypted messaging — so compromising one capability does not surrender the others, and each can be rotated on its own schedule. This is ordinary public-key cryptography arranged with unusual discipline, which is exactly the point: nothing exotic stands between you and operating your own identity infrastructure today.

The layer beneath credentials

DIDs are the foundation on which the rest of the decentralized-identity stack stands. A Verifiable Credential is a signed attestation from one DID about another ("this DID passed an electrician's certification"); a verifiable presentation lets the holder prove it to a third party, with selective disclosure revealing only the necessary fields. Together they form the model called Self-Sovereign Identity: you hold your identifiers and credentials the way you hold your coins.

A familiar shape

If this architecture feels familiar to a Bitcoiner, it should. Nostr already demonstrates key-based identity in production — an npub is control of a key, portable across every relay — and a DID generalizes the same principle with standardized resolution and rotation. D-Central's interest is practical: identity is one more layer of the stack that can either be rented from a platform or owned outright, and the tooling to own it now exists. Like every form of self-custody, it trades convenience for control — the trade this whole site is about.