Question: In a Voice Group Call Service (VGCS) supporting additional subscriber-related information, what happens to the additional info message on the SACCH (Slow Associated Control Channel) of the downlink voice group call channel at intervals determined by timer T2?
Option 1: The BSS (Base Station Subsystem) sends a new additional info message only when there is an update in subscriber-related information.
Option 2: The BSS stops transmitting the additional info message on the SACCH after the first transmission, regardless of the current talker's status.
Option 3: The BSS repeats the additional info message every T2 seconds until the current talker releases the uplink or is released by the network.
Option 4: The BSS transmits the additional info message on the SACCH only once, at the start of the voice group call.
Explanation: This option correctly describes the behavior specified for networks supporting the transmission of additional subscriber-related information in VGCS. Repeating the message at T2 second intervals ensures all participants in the group call have consistent and potentially updated information, until the talker's status changes or they are released by the network. The value of T2 being operator-specific with a default of 5 seconds highlights flexibility in managing network resource utilization versus information freshness.