DID Document

Since our DID method is a single, public key, the DID document itself may be reconstructed from a public key at any time. This layer exists purely for compatibility purposes. This is the W3C did:key specification.
Complete Example Document
DID documents of this type always follow this exact format:
{
  "@context": "https://w3id.org/did/v1",
  "id": "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH",
  "publicKey": [{
    "id": "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#pubkey",
    "type": "Ed25519VerificationKey2018",
    "controller": "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH",
    "publicKeyBase58": "B12NYF8RrR3h41TDCTJojY59usg3mbtbjnFs7Eud1Y6u"
  }],
  "authentication": [ 
    "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#pubkey"
  ],
  "assertionMethod": [ 
    "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#pubkey"
  ],
  "capabilityDelegation": [
    "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#pubkey"
  ],
  "capabilityInvocation": [
    "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#pubkey"
  ],
  "keyAgreement": [{
    "id": "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#kakey",
    "type": "X25519KeyAgreementKey2019",
    "controller": "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH",
    "publicKeyBase58": "JhNWeSVLMYccCk7iopQW4guaSJTojqpMEELgSLhKwRr"
  }]
}
​Example Source​
@context
The @context key states which version of the spec this DID conforms to.
For example: 'https://w3id.org/did/v1'
id
The id is the concatenation of the method did:key: with the public key.
For example
'did:nacl:Md8JiMIwsapml_FtQ2ngnGftNP5UmVCAUuhnLyAsPxI'
publicKey
The publicKey array MUST:
Contain EXACTLY one key record
The public keys MUST be identical
MUST use the index #pubkey
MUST have the type ED25519SignatureVerification2018
Be encoded in base64 (for transmission and consistency)
Example
"publicKey": [{
  "id": "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#pubkey",
  "type": "Ed25519VerificationKey2018",
  "controller": "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH",
  "publicKeyBase58": "B12NYF8RrR3h41TDCTJojY59usg3mbtbjnFs7Eud1Y6u"
}]
This contains a lot of redundant information, but is required to be compatible with other DID services
Unlike many other DID methods, a Fission Identity MUST contain exactly one key. Fission treats identity as pseudonymous at best and thus relegates access control to the realm of verifiable claims.
There is a need for non updateable DID's for use in IOT and other applications, where lack of network, size of code base and other such concerns are paramount to adoption. These concerns need to be addressed while not lowering the overall security guarantees.
~The uPort NaCL README​
Our motivation is focused primarily on universality. Rather than updating a document over time, the DID is minimal, immutable, and may be reconstructed from a key pair at any time.
authentication
The authentication array MUST:
Contain EXACTLY one key record
The key MUST be identical to #pubkey
Example
"authentication": [ 
  "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#pubkey"
]
assertionMethod
The assertionMethod array must contain EXACTLY the public key referenced in publicKey.id
Example
"assertionMethod": [ 
  "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#pubkey"
]
capabilityDelegation 
The capabilityDelegation array must contain EXACTLY the public key referenced in publicKey.id
Example
"capabilityDelegation": [
  "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#pubkey"
]
capabilityInvocation
The capabilityInvocation array must contain EXACTLY the public key referenced in publicKey.id
Example
"capabilityInvocation": [
  "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#pubkey"
]
keyAgreement
The keyAgreement array MUST
Include EXACTLY one key record
The id MUST match the public key, but indexed with #kakey
The type MUST set to X25519KeyAgreementKey2019
The controller MUST exactly match the public key
Include a base58-encoded public key
Example
"keyAgreement": [{
  "id": "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH#kakey",
  "type": "X25519KeyAgreementKey2019",
  "controller": "did:key:z6MkpTHR8VNsBxYAAWHut2Geadd9jSwuBV8xRoAnwWsdvktH",
  "publicKeyBase58": "JhNWeSVLMYccCk7iopQW4guaSJTojqpMEELgSLhKwRr"
}]