5.11 Configuration of Policy Control and Charging entities
23.0023GPPNetwork architectureRelease 17TS
The PCC functionality is comprised by the functions of the Policy and Charging Enforcement Function (PCEF), the Bearer Binding and Event Reporting Function (BBERF), the Policy and Charging Rules Function (PCRF), the Application Function (AF), the Online Charging System (OCS), the Offline Charging System (OFCS), the Traffic Detection Function (TDF), the Traffic Steering Support Function (TSSF) and the Subscription Profile Repository (SPR) or the User Data Repository (UDR). Figures 5.11-1 through to 5.11-4 describe the non-roaming and roaming architecture for PCC.
The PCRF can receive RAN User Plane Congestion Information from the RAN Congestion Awareness Function (RCAF).
The PCC architecture extends the architecture of an IP-CAN, where the Policy and Charging Enforcement Function is a functional entity in the Gateway node implementing the IP access to the PDN. The allocation of the Bearer Binding and Event Reporting Function is specific to each IP-CAN type and specified in the TS 23.203 [73].
PCC function makes it possible to apply policy and charging control to any kind of 3GPP IP CAN and any non-3GPP accesses connected via EPC complying with TS 23.402 [77]. Applicability of PCC to other IP CAN is not restricted; however, it shall be possible for the PCC architecture to base decisions upon the type of IP CAN used (e.g. GPRS, I-WLAN, etc.). Support for policy control and charging when local breakout and roaming are applied as specified in TS 23.401 [76] and TS 23.402 [77] is supported.
Figure 5.11-1: Overall PCC logical architecture (non-roaming) when SPR is used
Figure 5.11-2: Overall PCC logical architecture (non-roaming) when UDR is used
Figure 5.11-3: Overall PCC architecture (roaming with home routed access) when SPR is used
Figure 5.11-4: Overall PCC architecture for roaming with PCEF in visited network (local breakout) when SPR is used
NOTE 1: The SCEF acts as an AF (using Rx) in some service capability exposure use cases as described in TS 23.682 [132].
NOTE 2: The PCEF of PDN GW and the TDF can be further split into control plane entities (PGW-C and TDF-C) and user plane entities (PGW-U and TDF-U). The architecture reference model for the control plane and user plane separation is defined in TS 23.214 [145].