Question: In a Mission Critical Data (MCData) scenario with Session-based SDS, where should an MCData UE send Disposition Requests by default, and which alternative plane is used for Disposition Notifications when the primary method is unavailable?
Option 1: Media Plane for Requests; Signalling Plane for Notifications when Media Plane is down
Option 2: Signalling Plane for both Requests and Notifications, with no reliance on Media Plane
Option 3: Media Plane solely for all Disposition communications, without fallback
Option 4: Out-of-Band mechanism for all Session-based SDS Disposition communications
Explanation: According to the specified behavior for Session-based SDS in MCData, the default for sending Disposition Requests is via the Media Plane. However, when this primary method (Media Plane) is no longer available, the Signalling Plane is utilized as a fallback specifically for Disposition Notifications, ensuring continued communication capability under varying network conditions.