V-PCRF
Visited – Policy and Charging Rules Function
The PCRF is a policy decision point for subscriber data flows in the network. Using inputs from other network nodes, the PCRF will formulate rules which control how traffic flows (required QoS, restrictions, throttling, blocking, billing, etc) over the network down to individual subscriber SDF (Service Data Flow) granularity. The PCRF passes these rules to the PCEF (Policy and Charging Enforcement Function). In a roaming scenario, a Home PCRF can pass policy decision information to V-PCRF in the visited network.