title: difference between ports and service ports?
body: <p>While exploring marathon REST API, I came across two port numbers ( ports and service ports ) defined in the information ( JSON output) given by the following API call-<br>
  <code>curl http://x.y.z.w:8080/v2/tasks | python -m json.tool | less</code><br>
  The sample output is as:   </p>
  
  <pre><code>{
    "tasks":[
      {
        "appId":"/test",
        "host":"172.20.75.145",
        "id":"test.1fc922a9-f4c8-11e5-8bff-005056a76a7f",
        "ipAddresses":[
  
        ],
        "ports":[
          31313
        ],
        "servicePorts":[
          10000
        ],
        "slaveId":"2130f59b-7289-40eb-b24d-72f0c6fe94c8-S1",
        "stagedAt":"2016-03-28T09:33:26.859Z",
        "startedAt":"2016-03-28T09:33:26.936Z",
        "version":"2016-03-28T09:33:26.800Z"
      }
    ]
  }
  </code></pre>
  
  <p>Does any one know the difference between ports and servicePorts here? Please also add more information.</p>