Add support for Decentralized Identifiers (DIDs) in Party Object

[howethomas]

did

If a Decentralized Identifier (DID) is known for the party, it can be included in the did parameter.

• did: "String" (optional)

The value of the did parameter MUST be a valid DID URI that enables verifiable, decentralized digital identity for the party. DIDs are designed to be decoupled from centralized registries and identity providers, allowing the controller of the DID to prove control without requiring permission from other parties. The DID can refer to any subject (person, organization, thing, etc.) as determined by the controller of the DID.

Attaching DID Documents

An alternative approach to including DIDs in the Party Object is to add Attachment Objects containing the complete DID documents for each party. This approach provides more comprehensive identity information including cryptographic material, verification methods, and services that enable a DID controller to prove control. When using this approach:

1. Create an Attachment Object for each party's DID document
2. Set the mediatype to "application/did+json" (or appropriate mediatype)
3. Include a reference to the party in the attachment's party parameter
4. Consider adding a custom type/purpose indicator that this is a DID document

The DID document approach provides richer identity information that can be used for verification beyond simple identification.

[dgpetrie]

Need a W3C reference for the normative reference section.

[howethomas]

All set, updated reference.

[dgpetrie]

Merged into vcon-core fork