An example of an unsolicited attachment - provision of additional information

{
  "resourceType" : "Communication",
  "id" : "fm-attachment",
  "text" : {
    "status" : "generated",
    "div" : "<div xmlns=\"http://www.w3.org/1999/xhtml\">Attachment which is unsolicited</div>"
  },
  "identifier" : [{
    "system" : "http://www.providerco.com/communication",
    "value" : "12345"
  }],
  "status" : "completed",
  "category" : [{
    "coding" : [{
      "system" : "http://acme.org/messagetypes",
      "code" : "SolicitedAttachment"
    }]
  }],
  "subject" : {
    "reference" : "Patient/1"
  },
  "about" : [{
    "identifier" : {
      "system" : "http://happyvalley.com/claim",
      "value" : "12345"
    }
  },
  {
    "identifier" : {
      "system" : "http://www.BenefitsInc.com/fhir/claimresponse",
      "value" : "R3500"
    }
  }],
  "sent" : "2016-06-12T18:01:10-08:00",
  "recipient" : [{
    "identifier" : {
      "system" : "http://www.jurisdiction.com/insurer",
      "value" : "123456"
    }
  }],
  "sender" : {
    "identifier" : {
      "system" : "http://www.jurisdiction.com/provideroffices",
      "value" : "3456"
    }
  },
  "payload" : [{
    "contentAttachment" : {
      "contentType" : "application/pdf",
      "data" : "SGVsbG8=",
      "title" : "accident notes 20100201.pdf",
      "creation" : "2010-02-01T11:50:23-05:00"
    }
  },
  {
    "contentAttachment" : {
      "contentType" : "application/pdf",
      "url" : "http://example.org/docs/AB12345",
      "size" : "104274",
      "hash" : "SGVsbG8gdGhlcmU=",
      "creation" : "2010-02-01T10:57:34+01:00"
    }
  }]
}