All communication between JOAN devices, the JOAN Portal and the Microsoft Exchange calendar is managed through the official, standard NTLM authentication using the EWS API with access granted and certain credentials stored in encrypted form.
No calendar or event information is stored on our servers. The Visionect Software Suite only stores the email of the room's resource, all other information is gained through an API call, parsed and sent directly to the device. This information is temporarily stored in our cache, just to make sure the events are still displayed even if the calendar service experiences a downtime. Such information is never stored in our database.