Question: In a RANflex configuration with group call redundancy, where is timer T3 (related to supervising group call setup) implemented, and what triggers its start?
Option 1: Implemented in the MSC; Started when a positive Send Group Call Info result is returned to the VMSC
Option 2: Implemented in the GCR; Started when initial talker information is stored
Option 3: Implemented in the VMSC; Started when Send Group Call Info is received from the MSC
Option 4: Implemented in the BSC; Started when group call resources are allocated
Explanation: In a RANflex configuration with redundancy for group calls, timer T3 is implemented in the Group Call Register (GCR) to oversee group call setup. It starts when initial talker information is stored, enhancing the robustness of group call setups by monitoring from the point where key speaker details are recorded.