Imports System.IO
Imports System.Net
Imports System.Net.Sockets
Imports System.Text
Module Module1
    Dim server As Socket
    Dim ClientSocket As Socket
 
    Sub Main()
 
        ' Socket initialisieren
        Dim Server As New Socket(AddressFamily.InterNetwork, SocketType.Stream, _
          ProtocolType.IP)
        Dim IPHostInfo As IPHostEntry = Dns.Resolve(Dns.GetHostName)
        Dim ipAdress As IPAddress = IPHostInfo.AddressList(0)
        Dim localEP As New IPEndPoint(ipAdress, 930)
 
        ' Daten an das Socket binden
        Server.Bind(localEP)
        Console.WriteLine("Server wird gestartet ... " + Environment.NewLine)
 
        ' Socket aktivieren und Clientanruf abwarten
 
        Try
            Server.Listen(10)
            Console.WriteLine("LOG aktiv ... " + Environment.NewLine)
 
            ' Clientanfrage akzeptieren
            ClientSocket = Server.Accept
 
            Dim port As Int32 = CType(ClientSocket.RemoteEndPoint, _
              IPEndPoint).Port
            Dim TcpIP As String = CType(ClientSocket.RemoteEndPoint, _
            IPEndPoint).Address.ToString
 
            Console.WriteLine("Client connect : " + TcpIP.ToString + " : " + _
              port.ToString + Environment.NewLine)
 
            Messages()
 
        Catch ex As Exception
            Console.WriteLine(ex.ToString)
            Console.ReadLine()
        Finally
            ClientSocket.Shutdown(SocketShutdown.Both)
            ClientSocket.Close()
        End Try
 
    End Sub
 
    Sub Messages()
        Dim bytes(1024) As Byte
        Dim countBytesFromClient As Int32
 
        Do While True
 
            ' vom Client eine Mitteilung entgegen nehmen
            countBytesFromClient = ClientSocket.Receive(bytes)
            Dim str As String = Encoding.ASCII.GetString(bytes, 0, _
              countBytesFromClient)
            Console.WriteLine(str)
 
            Dim msg() As Byte = Encoding.ASCII.GetBytes(str)
            ClientSocket.Send(msg)
        Loop
 
    End Sub
End Module