{
  "event": "addLink",
  "payload": {
    "id": "of:0000000000000004/3-of:0000000000000003/4",
    "type": "direct",
    "online": true,
    "src": "of:0000000000000004",
    "srcPort": "3",
    "dst": "of:0000000000000003",
    "dstPort": "4"
  }
}