P2P on XP

Question

Hi,

I've been trying to create a small P2P application for testing purposes using WCF (System.Net.PeerToPeer namespace) but I'm having difficulties getting some simple code to work on XP.

This is my code to register a new peer name and then resolve any peers of a certain name that it can find.

Code Snippet

            var peerName = new PeerName("Test Peer", PeerNameType.Secured);
          
            _peerNameReg = new PeerNameRegistration(peerName, 80);
            _peerNameReg.Comment = "Test comment.";
            _peerNameReg.Start();

            testListBox.Items.Add(_peerNameReg.PeerName.ToString());

            var peerNameResolver = new PeerNameResolver();
            var result = peerNameResolver.Resolve(new PeerName("Test Peer", PeerNameType.Secured));

            foreach (var item in result)
                testListBox.Items.Add(item.PeerName.ToString());

This code works fine on Vista - the peer name is registered and PNRP resolution succeeds (though result contains zero records). On XP (SP3 with advanced networking installed) peer name registration succeeds but then I get the following exception on the line that calls peerNameResolver.Resolve.

System.Net.PeerToPeer.PeerToPeerException: Could not start name resolution. ---> System.Runtime.InteropServices.COMException (0x80631001): Exception from HRESULT: 0x80631001

   --- End of inner exception stack trace ---

   at System.Net.PeerToPeer.PeerNameResolver.Resolve(PeerName peerName, Cloud cloud, Int32 maxRecords)

   at System.Net.PeerToPeer.PeerNameResolver.Resolve(PeerName peerName, Cloud cloud)

   at P2pNetMessenger.MainWindow.OnInitialized(EventArgs e) in C:\Users\Alex\Documents\Visual Studio 2008\Projects\P2P Net Messenger\P2P Net Messenger\MainWindow.xaml.cs:line 40

   at System.Windows.FrameworkElement.TryFireInitialized()

   at System.Windows.FrameworkElement.EndInit()

   at System.Windows.Markup.BamlRecordReader.ElementEndInit(Object& element)

The HResult suggests that "An attempt has been made to access a cloud that does not exist." (see this), but even when I explicitly set the Cloud in code I receive the same error.

Is there perhaps something wrong with my XP configuration, or maybe there is a way to fix this issue in code?
Thanks in advance...

Answer 1

Hi,

I have a similar problem. This is my "server-side" code:

[CODE]

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Net.PeerToPeer;

using System.Net;

namespace TestPeerToPeerServer

{

    class Program

    {

        static void Main(string[] args)

        {

            PeerName peerName = new PeerName("TSFPeerServer", PeerNameType.Unsecured);

            PeerNameRegistration pnReg = new PeerNameRegistration(peerName, 8889, Cloud.AllLinkLocal);

            pnReg.Comment = "Server attualmente attivo";

            pnReg.Data = System.Text.Encoding.UTF8.GetBytes("Dati associati al peer");

            try

            {

                pnReg.Start();

                System.Console.WriteLine("Servizio attivo...");

            }

            catch (Exception exc)

            {

                System.Console.WriteLine(exc.Message);

            }

            ConsoleKeyInfo k;

            do

            {

                k = System.Console.ReadKey();

            }

            while (k.Key != ConsoleKey.Enter);

            System.Console.WriteLine("Fermo il servizio");

            pnReg.Stop();

        }

    }

}

[/CODE]

and this the "client-side" code:

[CODE]

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Net;

using System.Net.PeerToPeer;

namespace TestPeerToPeerClient

{

    class Program

    {

        static void Main(string[] args)

        {

            try

            {

                PeerNameResolver resolver = new PeerNameResolver();

                PeerName peerName = new PeerName("TSFPeerServer", PeerNameType.Unsecured);

                PeerNameRecordCollection results = resolver.Resolve(peerName);

                System.Console.WriteLine("Risoluzione dei nomi completata.\n", peerName);

                System.Console.WriteLine("Risultati per il nome: {0}", peerName);

                System.Console.WriteLine();

                foreach (PeerNameRecord record in results)

                {

                    System.Console.Write("Commenti:");

                    if (record.Comment != null)

                    {

                        Console.Write(record.Comment);

                    }

                    System.Console.WriteLine();

                    System.Console.Write("Dati:");

                    if (record.Data != null)

                    {

                        Console.Write(System.Text.Encoding.ASCII.GetString(record.Data));

                    }

                    System.Console.WriteLine();

                    System.Console.WriteLine("Endpoints:");

                    foreach (IPEndPoint endpoint in record.EndPointCollection)

                    {

                        Console.WriteLine("\t Endpoint:{0}", endpoint);

                        Console.WriteLine();

                    }

                }

                Console.ReadKey();

            }

            catch (Exception e)

            {

                System.Console.WriteLine(e.Message);

            }

        }

    }

}

[/CODE]

the problem is that if this two piece of software are executed by two Windows XP SP2 computers all works fine. If one of them is a Windows Server 2008 the client could not recognize the each other!

Have you got some hints?

Thank you a lot!