6.2.7 Bearer Binding and Event Reporting Function (BBERF)

23.2033GPPPolicy and charging control architectureRelease 17TS

6.2.7.1 General

The BBERF includes the following functionalities:

– Bearer binding.

– Uplink bearer binding verification.

– Event reporting to the PCRF.

– Sending or receiving IP‑CAN-specific parameters, to or from the PCRF.

6.2.7.2 Service data flow detection

The service data flow detection at the BBERF is identical to the detection at PCEF with the following modifications:

– If the service data flow is tunnelled at the BBERF, the BBERF uses information on the mobility protocol tunnelling header provided by the PCRF and the QoS rules to detect the service data flows.

For the uplink direction, the BBERF applies QoS rules with a bearer binding to the bearer that the packet arrived on. The uplink bearer binding verification is successful if there is a QoS rule with a matching uplink SDF filter. The BBERF shall discard packets for which the uplink bearer binding verification fails.

6.2.7.3 QoS Control

The ARP, GBR, MBR and QCI are used by the BBERF in the same way as in the PCEF for resource reservation.

When access network is not utilizing QCI based QoS parameters, the BBERF shall be able to convert a QoS class identifier value to QoS attribute values used in the access network and determine the QoS class identifier value from a set of QoS attribute values used in the access network.

NOTE: The definition of the mapping between QCI and Non 3GPP access specific QoS is outside of scope for 3GPP.

The BBERF controls the QoS that is provided to a combined set of service data flows. BBERF ensures that the resources which can be used by an authorized set of service data flows are within the "authorized resources" specified via the Gxx interface by "authorized QoS". The authorized QoS provides an upper bound on the resources that can be reserved (GBR) or allocated (MBR) for the service data flows.

In order to support the different IP‑CAN bearer establishment modes (UE-only or UE/NW), the BBERF shall support the same procedures for handling different IP‑CAN bearer establishment modes as specified for the PCEF in clauses 6.2.2.1 and 6.2.2.4.