UDP with multiple sender and one single receiver

Question

In a project I have multiple senders of UDP data, but only a single receiver.

If traffic gets higher, the receiver "forgets" lots of packets. I know that this is a problem inherent to UDP, but I want to minimize the number of lost packets.

I have read this SO question before!

Here is my code (Please excuse the massive code blocks, but I wanted the example to be self contained)

Sender side:

public class UdpSender
{
    private static int portNumber = 15000;

    public void Send(string data)
    {
        var udpServer = new UdpClient();
        var ipEndPoint = new IPEndPoint(IPAddress.Broadcast, portNumber);
        byte[] bytes = Encoding.ASCII.GetBytes(data);
        udpServer.Send(bytes, bytes.Length, ipEndPoint);
        udpServer.Close();
    }
}


class Program
{
    static void Main(string[] args)
    {
        var sender = new UdpSender();
        var count = 100000;

        for (var i = 0; i < count; ++i)
        {
            sender.Send(i.ToString());
        }

        Console.ReadKey();
    }
}

Receiver side:

public class UDPListener
{
    private static int portNumber = 15000;
    private readonly UdpClient udp = new UdpClient(portNumber);

    public volatile int CountOfReceived = 0;

    public void StartListening()
    {
        this.udp.BeginReceive(Receive, new object());
    }

    private void Receive(IAsyncResult ar)
    {
        Interlocked.Increment(ref CountOfReceived);

        IPEndPoint ip = new IPEndPoint(IPAddress.Any, portNumber);
        byte[] bytes = udp.EndReceive(ar, ref ip);
        string message = Encoding.ASCII.GetString(bytes);
        StartListening();
    }
}

class Program
{
    static void Main(string[] args)
    {
        var listener = new UDPListener();

        listener.StartListening();

        while (true)
        {
            Console.WriteLine(listener.CountOfReceived.ToString("000,000,000"));
        }

    }
}

Right now if I start 5 sender applications in parallel, only about a quarter of the messages is received. This is only on my local machine.

What can I do to minimize packets lost?

Related - http://stackoverflow.com/questions/4439954/improving-udp-reliability — Daniel Kelley, Aug 06 '14 at 14:18
thinking about the speed you're sending your packets on their trip i would say that the sinks buffer might be filled in a bit of time - increasing the buffer size could solve this issue, i guess. — Matthias R., Aug 06 '14 at 14:21
Yes, that really helps! Have increased buffer size to 8mb, now all messages get received. Are there any issues with a buffer of that size? — Mare Infinitus, Aug 06 '14 at 14:36
@Matt Now I chose 8MB as my buffer size, since then all packets are received. Are there any known issues regarding buffers of "enormous" size? (as the default size is only 8K on my machine). If you post your comment as an answer, I'll accept it. — Mare Infinitus, Aug 07 '14 at 08:15

score 2 · Accepted Answer · edited May 23 '17 at 12:05

2

thinking about the speed you're sending your packets on their trip i would say that the sinks buffer might be filled in a bit of time - increasing the buffer size (as shown here) could solve this issue, i guess.

edited May 23 '17 at 12:05

Community

1
1

answered Aug 07 '14 at 08:26

Matthias R.

441
2
15

1

For future readers an example would probably be appreciated or at least some link to a resource which explains it. At the moment it is a very scarce answer (even though it helped the OP). – default Aug 07 '14 at 08:31

UDP with multiple sender and one single receiver

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