title: how to block telnet somehow
body: <p>Scenario: 
  Scenario:
  In this part we have two System Administrators who administer a system which has
  windows OS installed. First Admin is beside the system and second Admin is on
  vacation. Both have username and password. In a negligence, second Admin left his
  notebook containing login information and Server IP in a CafeNet. An intruder from a
  black hat hackers group found it and decided to go another unknown place to access
  the server using telnet. But that takes 10 minutes to get there. Imagine you informed
  right from beginning minute. Now help first Admin to configure the system in a way
  that while receiving any telnet connection, it warns the intruder with a message and
  let him know that we have already covered this security hole. But, if it was a request
  of second Admin (he calls or chat you!), then we let him to go ahead with telnet
  connection!
  Note: For some reasons, we can not stop Telnet, or change password today!</p>