Wenas,

Si me podeis ayudar partiendo de un chat client solo me falta la parte del server que deveria ser por ms-dos en consola con Socket.

Código:
Imports System.Net.Sockets
Imports System.Text
Public Class Form1
 Dim client As TcpClient
 Dim data() As Byte

 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnstart.Click
 If txtserver.Text = "" Or txtport.Text = "" Or txtnick.Text = "" Then
 MsgBox("Ingrese Datos para la Conexion")
 Exit Sub
 End If

 If btnstart.Text.Trim = "START" Then
 MsgBox("in")
 Try
 '---connect to server
 client = New TcpClient
 client.Connect(txtserver.Text.Trim, txtport.Text.Trim)
 ReDim data(client.ReceiveBufferSize)
 SendMessage(txtnick.Text)
 '---read from server
 client.GetStream.BeginRead( _
 data, 0, CInt(client.ReceiveBufferSize), _
 AddressOf ReceiveMessage, Nothing)
 btnstart.Text = "OUT"
 btnsend.Enabled = True
 Catch ex As Exception
 MsgBox(ex.ToString)
 End Try
 Else
 'DESCONECTA
 Disconnect()
 btnstart.Text = "START"
 btnsend.Enabled = False
 End If


 End Sub

 Private Sub btnsend_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnsend.Click
 SendMessage(txtmsg.Text.Trim)
 txtmsg.Clear()
 End Sub

 Public Sub Disconnect()
 '---DESCONECTA
 Try
 client.GetStream.Close()
 client.Close()
 Catch ex As Exception
 MsgBox(ex.ToString)
 End Try
 End Sub

 Public Sub ReceiveMessage(ByVal ar As IAsyncResult)
 Try
 Dim bytesRead As Integer
 bytesRead = client.GetStream.EndRead(ar)
 If bytesRead < 1 Then
 Exit Sub
 Else
 Dim para() As Object = {System.Text.Encoding.ASCII.GetString(data, 0, bytesRead)}
 Me.Invoke(New delUpdateH(AddressOf Me.UpdateH), para)
 End If
 client.GetStream.BeginRead( _
 data, 0, CInt(client.ReceiveBufferSize), AddressOf ReceiveMessage, Nothing)
 Catch ex As Exception
 End Try
 End Sub

 Public Delegate Sub delUpdateH(ByVal str As String)
 Public Sub UpdateH(ByVal str As String)
 rtxt.AppendText(str)
 txtmain.AppendText(str)
 End Sub

 Public Sub SendMessage(ByVal message As String)
 Try
 '---send a message to the server
 Dim ns As NetworkStream = client.GetStream
 Dim data As Byte() = System.Text.Encoding.ASCII.GetBytes(message)
 '---send the text---
 ns.Write(data, 0, data.Length)
 ns.Flush()
 Catch ex As Exception
 MsgBox(ex.ToString)
 End Try
 End Sub

End Class
Si me podies ayudar a crear el server

Gracias,