Internet Connection Check using 204 HTTPStatusCode

Questions & Answers
1

I’ve been working on an Internet Connection Checker…

I’ve tried many things, from pinging to WebRequests, from RESTful APIs to socket beacons.

The one thing I found most reliable and performatic, considering Unity restrictions, was to make a WebRequest to a ‘no content’ web page. Such as Google’s 204 Generator.

This will return a HttpWebResponse with the ‘No Content’ HttpStatusCode, which is labeled as number 204. This response has a length of 0 bytes, which means the only data that would be downloaded is the Header of the response.

Not only that, but since the page will return a fixed status code, you can check if the user is trapped inside a Walled Garden.

Although I didn’t find any downsides on using this, I would like a second (and more) opinion on the topic.

For instance, would this method be suited for constant streaming games? Such as MOBAs or real time multiplayer games?
Is the overhead of a WebRequest plus the header from the WebResponse large enough for it to be not performatic data wise?
Is this a reliable way to check for internet connection?
Are there any problems worth mentioning?
Have you guys ever tried this on a large scale project?

Thank you!

Ps.: Below is a simplified version of what I mean.

public enum ConnectionStatus
	{
		ERROR,
		NO_DNS_CONNECTION,
		WALLED_GARDEN,
		CONNECTED
	}
	
public static class ConnectionChecker
{
	private static Uri google204 = new Uri("http://clients3.google.com/generate_204");
	
	private static Thread checkerThread = null;
	private static bool threadIsRunning = false;
	private static bool threadShouldStop = false;

	public static ConnectionStatus Status { get; private set; }

	public static void StartConnectionCheck ()
	{
		if (threadIsRunning && !threadShouldStop)
			return;
		
		if (checkerThread == null)
			checkerThread = new Thread (CheckConnection);

		checkerThread.Start ();
	}
	
	public static void StopConnectionCheck ()
	{
		threadShouldStop = true;
	}
	
	private static void CheckConnection ()
	{
		threadIsRunning = true;
		
		while (!threadShouldStop)
		{
			WebRequest request;
			HttpWebResponse response;

			try
			{
				request = WebRequest.Create (google204);
				response = (HttpWebResponse) request.GetResponse();
			}
			catch (WebException webException)
			{
				Status = ConnectionStatus.NO_DNS_CONNECTION;
				continue;
			}
			catch (Exception e)
			{
				Status = ConnectionStatus.ERROR;
				continue;
			}

			if (response.StatusCode == HttpStatusCode.NoContent)
				Status = ConnectionStatus.CONNECTED;
			else
				Status = ConnectionStatus.WALLED_GARDEN;

			Thread.Sleep(1000);

			threadShouldStop = threadShouldStop || ThreadShouldStop();
		}
			
		threadIsRunning = false;
		threadShouldStop = false;
	}

	private static bool ThreadShouldStop ()
	{
		return 	Thread.CurrentThread.ThreadState == ThreadState.StopRequested ||
				Thread.CurrentThread.ThreadState == ThreadState.SuspendRequested ||
				Thread.CurrentThread.ThreadState == ThreadState.AbortRequested;
	}
}
2

hey man，have you found the solution for it?