Policy and Charging Control Function (PCRF) is defined using the policy and charging protocol architecture as outlined by 3GPP TS23.203 as the baseline.
The purpose of the function is to act as Quality of Service (QoS) coordinator between the external PDN (Public Data Network) and the EPC (Evolved Packet Core), managing:
Verification and enforcement of QoS parameters.
Facilitate usage charging in accordance with QoS parameters.
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