title: Can Bluetooth masters be connected together?
body: <p>I am wondering if two Bluetooth masters can be connected to each other.
  I think it is not possible because there should be only one master in each piconet.
  Anyways, here is one scenario.</p>
  
  <p>Suppose that there are two smart phones, each one is using bluetooth headset or connected to some device, thus both phones are working as masters.
  Now, one smart phone wants to send files via bluetooth to the other smart phone.
  In this case, is it possible that the phones are connected?</p>
  
  <p>If they support role switch, one may be switched to a slave.
  But in this case, I think the already established connections would be broken because they will lose the master.</p>
  
  <p>If I want to send files from one master to another master, how can I do this?
  Is it possible or impossible??</p>