Использование STUN

Imports System.Net.Sockets
Imports System.Net
Imports System.Threading
 
Imports LumiSoft.Net.STUN.Client
 
Public Class Form1
    Dim sock As Socket = New Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp)
    Dim publicEP As IPEndPoint
 
    Public ThreadReceive As System.Threading.Thread
 
    Dim sender As New IPEndPoint(IPAddress.Any, 0)
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        sock.Bind(New IPEndPoint(IPAddress.Any, 0))
 
        Dim result As STUN_Result = STUN_Client.Query("stunserver.org", 3478, sock)
 
        If Not (result.NetType = STUN_NetType.UdpBlocked) Then
                 publicEP = result.PublicEndPoint
 
                 ThreadReceive = New System.Threading.Thread(AddressOf receive)
                 ThreadReceive.Start()
        Else
                 MsgBox(":(")
        End If
    End Sub
 
    Private Sub receive()
        Dim msg() As Byte = New [Byte](255) {}
        Dim _from As IPEndPoint = New IPEndPoint(IPAddress.Any, 0)
 
        While (1)
            If Not (sock.ReceiveFrom(msg, SocketFlags.None, _from) = -1) Then
                MsgBox(System.Text.Encoding.ASCII.GetString(msg))
            End If
        End While
    End Sub

Imports System.Net.Sockets
Imports System.Net
Imports System.Text
 
Public Class Form1
    Dim sock As Socket = New Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp)
 
    Dim recIP As IPAddress = IPAddress.Parse("178.212.101.30")
    Dim recPORT As Integer = 53072
    Dim rmtIP As IPEndPoint = New IPEndPoint(recIP, recPORT)
 
    Dim msg As Byte() = New Byte() {}
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        msg = Encoding.ASCII.GetBytes("test")
 
        sock.Connect(rmtIP)
        sock.SendTo(msg, rmtIP)
    End Sub
End Class