Section: B.2.1 APN Rate Control in the PGW
Content: To enable APN rate control it shall be configured in the PGW per APN. The APN rate control parameters, if configured, shall consist of: - the maximum number of DL user data packets per time unit, - the maximum number of UL user data packets per time unit, - an indication whether the UE is allowed to send additional exception reports when the limit for the UL APN rate control has been reached , and - if UE supports it, the maximum number of additional UL exception reports per time unit. Possible time units shall be, minute, hour, day or week. If the UE does not indicate APN rate control support, the GGSN/PGW may refrain from providing APN rate control information to the UE. NOTE 1: The UE indicates support for APN rate control with help of an indicator in the Protocol Configuration Options IE (PCO IE) or the Extended Protocol Configuration Options IE (ePCO IE), see 3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ]  [54] or 3GPP TS 24.301[ Non-Access-Stratum (NAS) protocol for Evolved Packet System (EPS); Stage 3 ]  [84] for IE definition. The APN rate control indicator within the PCO/ePCO IE is received at IP-CAN session establishment. NOTE 2: The UE and network support of the ePCO IE, is indicated with help of the Indication IE. The ePCO support indication within the Indication IE can be received at IP-CAN session establishment or at IP-CAN session modification. See 3GPP TS 29.274[ 3GPP Evolved Packet System (EPS); Evolved General Packet Radio Service (GPRS) Tunnelling Protocol for Control plane (GTPv2-C); Stage 3 ]  [81] for IE definition. If the APN rate control is supported by the UE and the Indication IE is received indicating support of ePCO IE at the IP-CAN session establishment request and the PGW supports the ePCO IE, the PGW shall in the reply, if configured for the APN used, include APN UL rate control parameters in the ePCO IE, see 3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ]  [54] for IE definition. If the ePCO IE is not supported the PGW shall use the PCO IE. The GGSN shall use the PCO IE. If the APN rate control UL parameter(s) is modified and the ePCO IE is supported, the PGW shall initiate an IP-CAN session modification procedure and include the APN UL rate control parameters in the ePCO IE. If the ePCO IE is not supported the PGW shall use the PCO IE. The GGSN shall use the PCO IE. The GGSN/PGW shall enforce the APN rate control per UE and APN according to the configuration for DL and may enforce APN rate control for UL, e.g. when the PGW have indicated to the UE that the UE is not allowed to send exception reports when the limit for the UL APN rate control has been reached. NOTE 3: The UE locally enforces this uplink APN rate control instruction. The UE considers this APN rate control instruction as valid until it receives a new one from the GGSN/PGW.