Question: In a 3GPP Access (PMIP-based) architecture, where is the Policy and Charging Enforcement Function typically allocated?
Option 1: Serving GW
Option 2: PDN GW
Option 3: Mobile Management Entity (MME)
Option 4: User Equipment (UE)
Explanation: In the context of 3GPP Access architectures utilizing PMIP, the Policy and Charging Enforcement Function plays a crucial role in managing network resources and enforcing policy decisions. Allocating this function to the PDN GW allows for efficient control over data plane traffic, as the PDN GW is responsible for interfacing with external packet data networks. This allocation enables effective policy enforcement and charging control at the point of intersection between the 3GPP network and external IP networks.