Exchange Server's primary purpose is to send, receive, and store messages. In Exchange Server versions 2007 and 2010, message delivery was handled by an Exchange server running the Hub Transport role. A message would be generated on a Mailbox server, the Mailbox server would notify a Hub Transport server that a new message was ready, and the Hub Transport server would pick up the new message for processing.
In Exchange Server 2013, the responsibility for moving messages from one mailbox to another moved to the Mailbox and Client Access roles; in Exchange Server 2016, the Mailbox role performs all the transport services.
IN THIS CHAPTER, YOU WILL LEARN TO: