{
  "event": "addDevice",
  "payload": {
    "id": "of:0000ffffffffff04",
    "type": "roadm",
    "online": true,
    "master": "myInstB",
    "labels": [
      "",
      "opt-4",
      "0000ffffffffff04"
    ],
    "metaUi": {
      "x": 1100,
      "y": 600
    }
  }
}