entations that expose a network interface
  described by a Thing Description will be referred to as "servers".
  Implementations that consume Thing Descriptions
  will be referred to as "clients".
  Note that these terms will be used with these specific definitions 
  in the following regardless of which device initiates
  network requests.  Normally the client initiates requests and the
  server responds.  However, in some protocols or sub-protocols that
  support push notifications (such as webhooks or MQ