How available meeting rooms are listed in MS Outlook?

I want to write a custom Outlook plugin, clicking on which a search form will open up. I will fill up the form with basic search criteria and on clicking the Search button all the available meeting rooms will be listed in a popup inside Outlook.I know that in Outlook New Meeting window does this work for us. But, I don't want to use that, but want to build it from scratch. I am planning to write the log in inside the plugin using Java. So, first I need to know the internal mechanism of how Outlook retrieves the list of available room, while creating a new meeting request.

After spending a few hours searching online, this is what I understood:

1. All the meeting rooms are listed in some database in a central server.
2. MS Outlook communicates to the Database via MS Exchange.
3. After running the search query on the DB, Exchange returns the list of rooms to Outlook.
4. User selects a room, and then send meeting request.
5. Exchange sends the meeting request to others.
6. Exchange also checks room availability with the Facility DB maintaining room status.
7. If meeting room booking fails, Exchange sends a message back to Outlook

Is my understanding correct? If not please correct me. Also, can you please tell me, what are the protocols Outlook and Exchange uses to communicate with each other and the DB? Can I code this in Java?

Thanks!