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[Tal Tikotzki]

I was doing some POCs recently testing the Netduino Plus 2 platform for a certain project.

One of the POCs was to test the web-server capability and limitations. I scanned the web and came into several examples of implementing a simple HTTP web server. It seems that the basic implementation is very common:

Socket Listening method which runs on a different thread:

private void RunServer()
{
    listenSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
    IPEndPoint BindingAddress = new IPEndPoint(IPAddress.Any, LISTEN_PORT);
    listenSocket.Bind(BindingAddress);
    listenSocket.Listen(1);
    IsServerRunning = true;
    while (true)
    {
        acceptedSocket = listenSocket.Accept();
        ProcessRequest();
        acceptedSocket.Close();
    }
}

The processing Method:

 private void ProcessRequest()
        {
            acceptedSocket.Receive(RECEIVE_BUFFER);
            var request = new string(UTF8Encoding.UTF8.GetChars(RECEIVE_BUFFER));
            var HEADER = UTF8Encoding.UTF8.GetBytes(HtmlPageHeader + "text/html" + "; charset=utf-8\r\nContent-Length: " + fileLength.ToString() + "\r\n\r\n");

            acceptedSocket.Send(HEADER, 0, HEADER.Length, SocketFlags.None);
            while (FILE_LENGTH > sendBuffer.Length)
            {
                fileStream.Read(sendBuffer, 0, sendBuffer.Length);
                acceptedSocket.Send(sendBuffer, 0, sendBuffer.Length, SocketFlags.None);
                FILE_LENGTH -= sendBuffer.Length;
            }
            fileStream.Read(sendBuffer, 0, (int)FILE_LENGTH);
            acceptedSocket.Send(sendBuffer, 0, (int)FILE_LENGTH, SocketFlags.None);
            
            fileStream.Close();
        }

let's assume that the ProcessRequest method, always returns the same simple html file (Text and Styles only, no images etc...)

This works okay when a Chrome browser running on a Windows 7 machine is trying to access the pages, click several times (slowly) on the refresh button works as well but:
1. Trying to access the Netduino web server from a chrome running on Android 4.0.4 result many times with Timeout
2. Constantly clicking the Refresh button (F5) of the Chrome@win7 causes an exception on the Netduino, this usually happens after 10-20 requests one after the other.
The exception is:

A first chance exception of type 'System.Net.Sockets.SocketException' occurred in Microsoft.SPOT.Net.dll

On the client side I'm getting:

Chromium's connection attempt to 10.XXX.YYY.55 was rejected.

Any ideas?

Tal