Available conference rooms are listed in MS Outlook

I want to write a custom Outlook plugin that will open a search form by clicking on it. I filled out the form with basic search criteria and by clicking the "Search" button, all available conference rooms will be displayed in a pop-up window in Outlook. I know that in the New Outlook Appointment window, this works for us. But I don't want to use this, but I want to build it from scratch. I am planning to write a log inside a plugin using Java. So first I need to know the internal mechanism of how Outlook retrieves the list of available rooms when creating a new meeting request.

After spending a few hours on the internet, I realized:

• All conference rooms are listed in some database on a central server.
• MS Outlook communicates with the database via MS Exchange.
• After running a database search query, Exchange returns a list of numbers to Outlook.
• The user selects a room and then submits a meeting request.
• Exchange sends a meeting request to other users.
• Exchange also checks the availability of the number while maintaining the status of the database database.
• If the conference room reservation fails, Exchange sends a message to Outlook

Do I understand correctly? If not, please correct me. Also, can you tell me what protocols Outlook and Exchange use to communicate with each other and with the DB? Can I code this in Java?