title: Which ports does android use?
body: <p>I have UnknownHostExeption, when i am using proxy. My App works finy in networks without proxy or with some proxies( not everyone). 
  I am aware that I need to setup proxy setings for networks with them
  for device: wify settings - advance - wifi proxy
  emulator: wireless networks - mobile networks - access points - telkia - proxy|port.
  I wish to know which essential options I have to ask admins to unlock for stable network comunications.</p>
  
  <pre><code>07-18 08:51:26.780: W/System.err(302): java.net.UnknownHostException: mirkvartir.ua
  07-18 08:51:26.780: W/System.err(302):  at java.net.InetAddress.lookupHostByName(InetAddress.java:513)
  07-18 08:51:26.780: W/System.err(302):  at java.net.InetAddress.getAllByNameImpl(InetAddress.java:278)
  07-18 08:51:26.780: W/System.err(302):  at java.net.InetAddress.getAllByName(InetAddress.java:242)
  07-18 08:51:26.780: W/System.err(302):  at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:136)
  07-18 08:51:26.780: W/System.err(302):  at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
  07-18 08:51:26.780: W/System.err(302):  at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
  07-18 08:51:26.780: W/System.err(302):  at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:348)
  07-18 08:51:26.780: W/System.err(302):  at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
  07-18 08:51:26.780: W/System.err(302):  at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
  07-18 08:51:26.780: W/System.err(302):  at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
  07-18 08:51:26.780: W/System.err(302):  at ua.mirkvartir.android.frontend.adapter.JSONParser.getJSONFromUrl(JSONParser.java:98)
  07-18 08:51:26.780: W/System.err(302):  at ua.mirkvartir.android.frontend.adapter.UserFunctions.loginUser(UserFunctions.java:76)
  07-18 08:51:26.787: W/System.err(302):  at ua.mirkvartir.android.frontend.LoginActivity$Login.doInBackground(LoginActivity.java:185)
  07-18 08:51:26.787: W/System.err(302):  at ua.mirkvartir.android.frontend.LoginActivity$Login.doInBackground(LoginActivity.java:1)
  07-18 08:51:26.787: W/System.err(302):  at android.os.AsyncTask$2.call(AsyncTask.java:185)
  07-18 08:51:26.787: W/System.err(302):  at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
  07-18 08:51:26.787: W/System.err(302):  at java.util.concurrent.FutureTask.run(FutureTask.java:137)
  07-18 08:51:26.787: W/System.err(302):  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
  07-18 08:51:26.787: W/System.err(302):  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
  07-18 08:51:26.787: W/System.err(302):  at java.lang.Thread.run(Thread.java:1096)
  </code></pre>