Question: In an E-UTRAN, which type of signaling is used for the SgNB Counter Check procedure initiated by the en-gNB to verify PDCP COUNTs for SN terminated bearers?
Option 1: Non-UE Associated Signaling (e.g., for general network management)
Option 2: UE-Unassociated Signaling (for cell-specific operations)
Option 3: Control Plane Signaling (primarily for RRC and NAS messages)
Option 4: UE-Associated Signaling (since it involves specific UE context)
Explanation: The correct answer is Option 4 because the SgNB Counter Check procedure, as described, involves verifying PDCP COUNTs associated with Specific Network (SN) terminated bearers for a particular User Equipment (UE). This implies that the signaling must be tied to the context of that UE, making UE-Associated Signaling the appropriate choice. This type of signaling is used when procedures are specific to a UE's session or bearers, ensuring the integrity and management of that UE's network interaction.