InstantMessagingCall is the class that supports instant messaging-based communication.
Assembly: Microsoft.Rtc.Collaboration (in Microsoft.Rtc.Collaboration.dll)
Instant messaging communication is realtime, text-based communication. InstantMessagingCall is an implementation of the abstract Call class. It implements signaling for instant messaging calls. Actual text messages are exchanged on an instance of InstantMessagingFlow, which is created at the time when the call is established.