6.4b APN related policy information
23.2033GPPPolicy and charging control architectureRelease 17TS
The purpose of the APN related policy information is to provide policy and charging control related information that is applicable to all IP‑CAN sessions of a UE to the same APN. The PCRF provides APN related policy information to the PCEF using the PCC provision procedure together with PCC rules or separately.
Table 6.4b-1 lists the applicable PCC specific APN related policy information.
Table 6.4b-1: PCC specific APN related policy information
Attribute |
Description |
PCRF permitted to modify the attribute |
Scope |
Authorized APN-AMBR |
Defines the APN-AMBR for the total bandwidth usage of non-GBR QCI traffic at the APN. |
Yes |
All IP‑CAN sessions for the same UE within the same APN |
Subsequent APN-AMBR (NOTE 1) |
Defines the APN-AMBR for the total bandwidth usage of non-GBR QCI traffic at the APN to be applied by the PCEF when the APN-AMBR change time is reached. |
No |
All IP‑CAN sessions for the same UE within the same APN |
APN-AMBR change time (NOTE 1) |
Defines the time at which the PCEF shall apply the Subsequent APN-AMBR for the total bandwidth usage of non-GBR QCI traffic at the APN. |
No |
All IP‑CAN sessions for the same UE within the same APN |
NOTE 1: Both parameters shall be provided together. The PCRF may provide up to four instances of them. If multiple instances are provided, the values of the APN-AMBR change time have to be different and should not be too close to each other in order to reduce the risk for signalling overload. NOTE 2: The PCRF may replace all instances that have been provided previously with a new instruction. A previously provided Subsequent APN-AMBR or APN-AMBR change time cannot be individually modified. |
The PCRF may provide the (unconditional) Authorized APN-AMBR in every interaction with the PCEF. The PCEF shall apply the Authorized APN-AMBR as APN-AMBR for all IP‑CAN sessions of the UE to the same APN and shall communicate the changed APN-AMBR to the UE.
NOTE 1: There is always an unconditional value for the APN-AM BR available at the PCEF. The initial value is received as Subscribed APN-AMBR in an access specific manner and the PCRF can overwrite it by providing an Authorized APN-AMBR.
NOTE 2: In order to reduce the risk for signalling overload, the PCRF should avoid simultaneous provisioning of Authorized APN-AMBR for many UEs (e.g. by spreading over time).
The Authorized APN-AMBR may be provided together with conditions, i.e. a list of RAT types and/or a list of IP-CAN types. One or multiple instances of conditional APN-AMBR, with different conditions, may be provided by the PCRF. The PCEF shall apply a conditional Authorized APN-AMBR as APN-AMBR only if the current RAT type and IP-CAN type match one of the RAT types and IP-CAN types specified in the conditions, respectively. Otherwise the PCEF shall apply the unconditional Authorized APN-AMBR as APN-AMBR. A changed APN-AMBR shall be communicated to the UE.
NOTE 3: Guidance what conditional Authorized APN-AMBR value to use in case the current RAT type and IP-CAN type match multiple conditional Authorized APN-AMBRs is specified in stage 3.
Conditional Authorized APN-AMBR(s) are not applied for a PDN connection supporting NBIFOM.
Upon PCRF changing the unconditional Authorized APN-AMBR or providing a conditional Authorized APN-AMBR, the PCEF shall discard any previously received conditional Authorized APN-AMBR.
The PCRF may provide the unconditional and/or one or multiple instances of conditional Authorized APN-AMBR together with an APN-AMBR change time, referred to as Subsequent APN-AMBR. When the APN-AMBR change time is reached, the PCEF shall apply the unconditional and/or conditional Subsequent APN-AMBR as unconditional and/or conditional Authorized APN-AMBR and discard any previously applied conditional Authorized APN-AMBRs.
NOTE 4: The modification is made in the same way as if the PCRF had modified the Authorized APN-AMBR at that point in time.
Up to four instances of Subsequent APN-AMBR may be provided by the PCRF. The PCEF shall discard any previously received Subsequent APN-AMBR instances on explicit instruction as well as whenever the PCRF provides a new instruction for one or more subsequent changes to the APN-AMBR or any other subsequent parameter.
NOTE 5: In order to provide further Subsequent APN-AMBRs in a timely fashion the PCRF can use its own clock to issue the desired changes or use the Revalidation time limit parameter (clause 6.4) to trigger a PCEF request for a policy decision.