{
   "version":"1.0",
   "id":"6f57f5fa-1cd1-45be-a5c3-fb209be1e0ec",
   "timestamp":"2025-05-24T06:14:00Z",
   "sender":{
      "name":"Radiology Clinic A",
      "id":"org:au.gov.health.123456",
      "contact":"imaging@clinica.org.au",
      "assertion":{
         "signing_key":{
            "alg":"Ed25519",
            "public_key":"<base64>",
            "fingerprint":"SHA256:4f06faee"
         },
         "key_reference":"aurabox://org/clinic-a#key-ed25519",
         "signed_fields":[
            "id",
            "name",
            "contact",
            "manifest_hash"
         ],
         "signature":"<base64sig>",
         "expires_at":"2025-07-07T00:00:00Z",
         "directory_attestation":{
            "provider":"aurabox",
            "attestation_signature":"<JWS>",
            "attestation_timestamp":"2025-06-07T14:01:00Z",
            "attestation_public_key":"<base64>"
         }
      }
   },
   "requester":{
      "name":"Dr John Smith",
      "id":"org:au.gov.health.55555",
      "contact":"smith@clinicb.org.au",
      "assertion":{
         "signing_key":{
            "alg":"Ed25519",
            "public_key":"<base64>",
          "fingerprint":"SHA256:4f06faee"
         },
         "key_reference":"aurabox://org/clinic-b#key-ed25519",
         "signed_fields":[
            "id",
            "name",
            "contact"
         ],
         "signature":"<base64sig>",
         "expires_at":"2025-07-07T00:00:00Z",
         "directory_attestation":{
            "provider":"aurabox",
            "attestation_signature":"<JWS>",
            "attestation_timestamp":"2025-06-07T14:01:00Z",
            "attestation_public_key":"<base64>"
         }
      }
   },
   "receiver":[
      {
         "name":"Radiology Clinic B",
         "id":"org:au.gov.health.987654",
         "contact":{
            "system":"phone",
            "value":"+61049555555"
         },
         "assertion":{
            "signing_key":{
               "alg":"Ed25519",
               "public_key":"<base64>",
               "fingerprint":"SHA256:4f06faee"
            },
            "key_reference":"aurabox://org/clinic-b#key-ed25519",
            "signed_fields":[
               "id",
               "name",
               "contact"
            ],
            "signature":"<base64sig>",
            "expires_at":"2025-07-07T00:00:00Z",
            "directory_attestation":{
               "provider":"aurabox",
               "attestation_signature":"<JWS>",
               "attestation_timestamp":"2025-06-07T14:01:00Z",
               "attestation_public_key":"<base64>"
            }
         }
      }
   ],
   "security":{
      "classification":"confidential",
      "payload_hash":"sha256:4f06faee",
      "signature":{
         "alg":"RS256",
         "sig":"MEUCIBnA...",
         "hash":"sha256:4f06faee..."
      },
      "encryption":{
         "algorithm":"AES-256-GCM",
         "ephemeral_public_key":"<base64>",
         "iv":"<base64>",
         "auth_tag":"<base64>"
      }
   },
   "extensions":{
      "custom_tags":[
         "teaching",
         "priority-review"
      ]
   }
}