Hi Marcin,

Please have a look at the example here, which covers pinging the server, getting a roundtip time and syncing Gametime accross different time zones using Gamesparks Real Time Api.

-If you wish to ping an ip address of your choice from Unity:

sing UnityEngine;
using System.Collections;

public class Check_InternetConnection : MonoBehaviour {

  public bool isConnectedToInternet = false;
  public float maxTime = 2.0F;
  public float timeTaken = 0.0F;

  void Awake()
  {
  StartCoroutine("ConnectionTest");
  }

  IEnumerator ConnectionTest()
  {

  while (true)
  {
  yield return new WaitForSeconds(2f);// the interval between ping attempts

  Ping testPing = new Ping("8.8.8.8");//Google - or Ip of your choice.
  Debug.Log("Testing......" + testPing.ToString());

  timeTaken = 0.0F;

  while (!testPing.isDone)
  {

  timeTaken += Time.deltaTime;


  if (timeTaken > maxTime)
  {
  // if time has exceeded the maxtime, break out and return false
  isConnectedToInternet = false;
  break;
  }

  yield return null;
  }

  if (timeTaken <= maxTime)
  {
  isConnectedToInternet = true;
  }
  yield return null;
  }
  }

}

Thanks,

-Dave.