Question: In the context of UMTS and combined UMTS/GSM networks, what is a prerequisite for a PDP (Packet Data Protocol) context activation to be counted towards the 'Successful PDP context activation procedures initiated by MS' measurement?
Option 1: The MS (Mobile Station) initiates a 'PDP Context Deactivation' request immediately after.
Option 2: The GGSN (Gateway GPRS Support Node) is updated successfully upon completion.
Option 3: The SGSN (Serving GPRS Support Node) and GGSN are both bypassed in the procedure.
Option 4: The measurement type is exclusively set to 'GSM' (Global System for Mobile Communications).
Explanation: For a PDP context activation to be considered successful under this measurement, it requires not just the initiation by the MS but also the successful update of the GGSN. This ensures that both the mobile's request and the network's acknowledgment (via GGSN update) are aligned, marking the procedure as complete and successful from both ends. This is crucial for accurate performance management in UMTS and combined UMTS/GSM networks.