title: Jenkins Master to slave communication; port forwarding
body: <p>I am a newbie to Jenkins and to networking, and i have a basic question here ... 
  I have Server X with Jenkins Master installed and running , and in an other network(w) I have a machine B witch doesn't have dedicated external IP , so basically it gets the external IP address of the network.</p>
  
  <p>I know that the slave should connect to the master through a specific port .
  but how will the communication work from Master to Slave ?  i suppose i need some forwarding rules to that specific Ip of machine B,Do I ?,
  How can i get this to work ?
  Please guide me, I hope my question is clear enough </p>