Socket programming over internet - vb.net

Question

I am making just a simple chat system using socket programming technique in vb.net .
It works fine on local network but how to use that over internet ..
I also try Port forwarding on my router ... May be my way is wrong .
Please tell me the correct way for port forwarding .. and tell me how to connect client to the server ???
Am i have to use a public IP of server system ???
the server side code is this :
Imports System.Net.Sockets
Module Module1
Sub Main()
Console.WriteLine("")
Dim clientListener As New TcpListener(12380)
clientListener.Stop()
clientListener.Start()
Console.WriteLine("")
Dim mySocket As Socket = clientListener.AcceptSocket()
Console.WriteLine("")
Dim recieveBuff(225) As Byte
mySocket.Receive(recieveBuff, recieveBuff.Length, SocketFlags.None)
Dim str As String = System.Text.Encoding.ASCII.GetString(recieveBuff, 0, recieveBuff.Length).Trim(Microsoft.VisualBasic.ChrW(0))
While Not str.StartsWith(".")
Console.WriteLine(str)
mySocket.Receive(recieveBuff, recieveBuff.Length, SocketFlags.None)
str = System.Text.Encoding.ASCII.GetString(recieveBuff, 0, recieveBuff.Length).Trim(Microsoft.VisualBasic.ChrW(0))
End While
Console.WriteLine("")
clientListener.Stop()
End Sub
End Module
and the client side code is this : (those both are console applications)
Imports System.Net.Sockets
Imports System.IO
Module Module1
Sub Main()
Try
Console.WriteLine("Connecting to localhost ")
Dim serverListener As New TcpClient("192.168.1.103", 12380)
Dim readStream As Stream = serverListener.GetStream
serverListener.SendBufferSize = 256
Console.WriteLine("Input Lines:")
Dim str As String = Console.ReadLine()
While 370
Dim sendBuff As Byte() = System.Text.Encoding.ASCII.GetBytes(str)
readStream.Write(sendBuff, 0, sendBuff.Length)
If str.StartsWith(".") Then
GoTo Done
End If
str = Console.ReadLine()
End While
Done: Console.WriteLine("Done")
Catch exp As Exception
Console.WriteLine("Exception: " + exp.ToString())
End Try
End Sub
End Module

Answer 1

You will need to use the public IP if the client is outside of your LAN.

Answer 2

First you need to enable port forwarding in the router, port should be lie between 49152 and 65535 and Address would be the private address of the server ex:"192.168.1.x"
Make sure you start listening your server in the new port (the one between 49152 and 65535)
then go to canyouseeme.org
and type the new port that you used and press check port
if the result was success than your configuration was correct and your server now is accessible via internet ,if the result was a red Error then you might done something wrong,probably a firewall problem, or you need to change the router.
if you get success then you must change this line in every client instead of the old one:
Dim serverListener As New TcpClient(YourPublicIpAdrees,NewPort)
To get your public ip address go here myip.
This is how to send a socket over internet, try it and comment your result.