Decentralized Identifiers (DIDs)

Decentralized Identifiers (DIDs) are a new type of identifier that enables verifiable, decentralized digital identity. They are fully under the control of the DID subject, independent from any centralized registry, identity provider, or certificate authority.

Key Characteristics of DIDs

Decentralized: DIDs are not issued or managed by a centralized authority. They are created and managed by the entity they refer to, the DID subject.

Persistent: Once generated, DIDs are permanent, globally unique identifiers. They do not need to be recycled or reassigned.

Resolvable: DIDs can be resolved to DID Documents, which provide a way to discover metadata about the DID subject, such as public keys and service endpoints.

Cryptographically Verifiable: DIDs are linked to cryptographic material, allowing for the verification of the DID subject.

Structure of a DID

DIDs follow a specific format: did:<method>:<identifier>

did: This is a fixed part of the identifier and indicates that the identifier is indeed a DID.

method: This refers to the specific DID method specification that defines how the DID is implemented. Examples include btcr for Bitcoin, ethr for Ethereum, and sov for Sovrin.

identifier: This is the specific identifier created by the DID method. This part of the DID is unique to the DID subject.

DID Documents

When a DID is resolved, it points to a DID Document. This document contains information about the DID, such as the public keys for verifying digital signatures, service endpoints for interacting with the DID subject, and the authentication methods used to prove control over the DID.

DID Methods

Different DID methods specify how a DID is created, resolved, updated, and deactivated on a specific blockchain or network. Each DID method has a specification that outlines these operations according to the particular system's capabilities and features.

DID Use Cases

DIDs can be used for any digital interaction where it's necessary to verify an entity's control over a digital identifier. Some use cases include authentication, signing blockchain transactions, encrypting/decrypting messages, and granting/verifying permissions.

The Future of DIDs

As we move towards a more decentralized web, DIDs are poised to play a pivotal role. They provide a foundation for building systems where users are in control of their data, enhancing privacy, security, and user agency.