我有一个ac＃peer-2-peer项目，我的应用程序应该在用户设备中配置UPnP以打开端口并监听UDP数据报，我使用NATUPnP.dll Com来组建新的端点如下：
NATUPNPLib.UPnPNATClass upnpnat = new NATUPNPLib.UPnPNATClass();
NATUPNPLib.IStaticPortMappingCollection mappings = upnpnat.StaticPortMappingCollection;
mappings.Add(20000, "UDP", 20000, "192.168.8.102", true, "Local Web Server");
foreach (NATUPNPLib.IStaticPortMapping portMapping in mappings)
{
Console.WriteLine(portMapping.Description); //gives me "Local Web Server"
Console.WriteLine(portMapping.ExternalIPAddress); // gives me "10.178.196.123"
Console.WriteLine(portMapping.Enabled); // gives me "True"
}
Console.ReadKey();
在此之后，我用一个简单的UDP客户端编写一个简单的UDP监听器来测试我是否成功映射了新的端点（port forwarding）和 监听器的代码< / strong>是：
public static int Main()
{
bool done = false;
UdpClient listener = new UdpClient(listenPort);
IPEndPoint groupEP = new IPEndPoint(IPAddress.Any, listenPort);
string received_data;
byte[] receive_byte_array;
try
{
while (!done)
{
Console.WriteLine("Waiting for broadcast");
receive_byte_array = listener.Receive(ref groupEP);
Console.WriteLine("Received a broadcast from {0}", groupEP.ToString());
received_data = Encoding.ASCII.GetString(receive_byte_array, 0, receive_byte_array.Length);
Console.WriteLine("data follows \n{0}\n\n", received_data);
}
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
listener.Close();
return 0;
}
和 客户 ：
UdpClient udpSender = new UdpClient();
IPEndPoint localServerGateway = new IPEndPoint(IPAddress.Parse("10.178.196.123"), 20000);
string message = "testmessage";
byte[] messageBytes = Encoding.ASCII.GetBytes(message);
try
{
udpSender.Send(messageBytes, messageBytes.Length, localServerGateway);
}
catch (Exception error)
{
Console.WriteLine("Error while sending message: " + error.ToString());
}
udpSender.Close();
当我向环回地址（127.0.0.1）发送测试消息时，服务器控制台向我显示此消息并且每件事情都正常，但是当我向外部IP地址发送测试消息（10.178.196.123）时没有显示，所以我的问题是：我的代码有问题吗？如果不是为什么测试消息没有被服务器收到？这种方法是最合适的p2p应用方法（在我的情况下，打孔不是一种选择）？
映射端口并运行服务器（使用Netstat）后，这是我的连接：
Proto Local Address Foreign Address State
TCP 0.0.0.0:135 0.0.0.0:0 LISTENING
TCP 0.0.0.0:445 0.0.0.0:0 LISTENING
TCP 0.0.0.0:1025 0.0.0.0:0 LISTENING
TCP 0.0.0.0:1026 0.0.0.0:0 LISTENING
TCP 0.0.0.0:1027 0.0.0.0:0 LISTENING
TCP 0.0.0.0:1028 0.0.0.0:0 LISTENING
TCP 0.0.0.0:1029 0.0.0.0:0 LISTENING
TCP 0.0.0.0:2869 0.0.0.0:0 LISTENING
TCP 0.0.0.0:5357 0.0.0.0:0 LISTENING
TCP 127.0.0.1:1242 127.0.0.1:4823 ESTABLISH
TCP 127.0.0.1:1244 127.0.0.1:4836 ESTABLISH
TCP 127.0.0.1:4823 127.0.0.1:1242 ESTABLISH
TCP 127.0.0.1:4836 127.0.0.1:1244 ESTABLISH
TCP 192.168.8.102:139 0.0.0.0:0 LISTENING
TCP 192.168.8.102:2869 192.168.8.1:51156 TIME_WAIT
TCP 192.168.8.102:2869 192.168.8.1:51157 TIME_WAIT
TCP 192.168.8.102:2869 192.168.8.1:51158 TIME_WAIT
TCP 192.168.8.102:4683 198.252.206.25:443 ESTABLISH
TCP 192.168.8.102:4824 104.16.35.249:80 ESTABLISH
TCP 192.168.8.102:4831 172.217.19.238:443 ESTABLISH
TCP 192.168.8.102:4832 94.142.38.38:443 ESTABLISH
TCP 192.168.8.102:4835 94.142.38.53:443 ESTABLISH
TCP 192.168.8.102:4837 104.16.33.249:80 ESTABLISH
TCP 192.168.8.102:4839 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4840 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4841 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4842 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4843 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4844 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4845 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4846 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4847 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4848 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4849 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4850 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4851 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4852 192.168.8.1:50473 TIME_WAIT
TCP 192.168.8.102:4853 192.168.8.1:50473 TIME_WAIT
TCP [::]:135 [::]:0 LISTENING
TCP [::]:445 [::]:0 LISTENING
TCP [::]:1025 [::]:0 LISTENING
TCP [::]:1026 [::]:0 LISTENING
TCP [::]:1027 [::]:0 LISTENING
TCP [::]:1028 [::]:0 LISTENING
TCP [::]:1029 [::]:0 LISTENING
TCP [::]:2869 [::]:0 LISTENING
TCP [::]:5357 [::]:0 LISTENING
UDP 0.0.0.0:3702 *:*
UDP 0.0.0.0:3702 *:*
UDP 0.0.0.0:3702 *:*
UDP 0.0.0.0:3702 *:*
UDP 0.0.0.0:5355 *:*
UDP 0.0.0.0:20000 *:*
UDP 0.0.0.0:52766 *:*
UDP 0.0.0.0:55825 *:*
UDP 127.0.0.1:1900 *:*
UDP 127.0.0.1:63074 *:*
UDP 192.168.8.102:137 *:*
UDP 192.168.8.102:138 *:*
UDP 192.168.8.102:1900 *:*
UDP 192.168.8.102:63073 *:*
UDP [::]:3702 *:*
UDP [::]:3702 *:*
UDP [::]:3702 *:*
UDP [::]:3702 *:*
UDP [::]:5355 *:*
UDP [::]:52767 *:*
UDP [::]:55826 *:*
UDP [::1]:1900 *:*
UDP [::1]:63072 *:*
UDP [fe80::bc13:29c3:a8c3:c74a%16]:546 *:*
UDP [fe80::bc13:29c3:a8c3:c74a%16]:1900 *:*
UDP [fe80::bc13:29c3:a8c3:c74a%16]:63071 *:*