Content for  TS 23.060  Word version:  18.0.0

The GGSN sends an Update PDP Context Request (TEID, NSAPI, PDP Address, QoS Requested, Negotiated Evolved ARP, Prohibit Payload Compression, APN Restriction, MS Info Change Reporting Action, CSG Information Reporting Action, TFT, Protocol Configuration Options, BCM, APN-AMBR, Retrieve Location) message to the SGSN. The GGSN sets the Negotiated Evolved ARP based on local policy or PCC. The Allocation/Retention Priority of the QoS Profile Negotiated is derived from the Evolved ARP according to the mapping principles of TS 23.401, Annex E. QoS Requested indicates the desired QoS profile. The QoS Requested may be equal to, an upgrade or a downgrade compared to the current QoS of the PDP context. PDP Address is optional. The Prohibit Payload Compression indicates that the SGSN should negotiate no data compression for this PDP context. If the Bearer Control Mode is set to 'MS/NW', the TFT may be included in order to add, modify or delete the TFT related to the PDP Context (in accordance with the requirements in clauses 9.2.0 and 15.3.0). Protocol Configuration Options may contain the BCM as well as optional PDP parameters that the GGSN may transfer to the MS. BCM shall also be sent as a separate IE to the SGSN. BCM indicates the Bearer Control Mode applicable to all PDP Contexts within the activated PDP Address/APN pair. The GGSN shall only indicate Bearer Control Modes allowed according to the NRSN and NRSU previously indicated by the SGSN and MS respectively. The SGSN may restrict a desired QoS profile given its capabilities, the current load, the current QoS profile, and the subscribed QoS profile. The SGSN shall apply a Negotiated Evolved ARP even if it is different from the Subscribed Evolved ARP. The BCM is used by the SGSN to handle unexpected session management signalling. If the GGSN determines the active APN-AMBR needs to be modified, the APN-AMBR is included in the request message. If the modification is triggered by a change of the APN-AMBR only, then only one PDP context associated with that APN shall be modified. The SGSN recalculates the UE-AMBR if the APN-AMBR was received from the GGSN: see clause 15.2.2. "Retrieve Location" is indicated if requested by the PCRF. If the MS is in IDLE state and extended idle mode DRX is enabled for the MS, the SGSN will trigger Network Initiated Service Request Procedure from step 2 (which is specified in clause 6.12.2), and start a timer which is configured to a value smaller than the GTP re-transmission timer. If the SGSN receives no response from the MS before the timer expires, the SGSN rejects the Update PDP Context Request message with a rejection cause indicating that the MS is temporarily not reachable due to power saving and, if a Delay Tolerant Connection indication was set for the PDN connection, the SGSN sets the internal flag Pending Network Initiated PDN Connection Signalling.

In A/Gb mode, BSS packet flow context procedures may be executed. These procedures are defined in clause "BSS Context".

In Iu mode, radio access bearer modification may be performed by the RAB Assignment procedure.

The SGSN selects Radio Priority and Packet Flow Id based on QoS Negotiated, and sends a Modify PDP Context Request (TI, PDP Address, QoS Negotiated, Radio Priority, Packet Flow Id, TFT, PCO, WLAN offloadability indication) message to the MS. PDP Address is optional. If the MS indicated in the MS Network Capability it does not support BSS packet flow procedures, then the SGSN shall not include the Packet Flow Id. In A/Gb mode, the QoS Negotiated shall be included if modified and take into account the Aggregate BSS QoS Profile, if any, returned from the BSS. The TFT is included only if it was received from the GGSN in the Update PDP Context Request message. Protocol Configuration Options contains the BCM as well as optional PDP parameters that the GGSN may transfer to the MS. Protocol Configuration Options is sent transparently through the SGSN. BCM indicates the Bearer Control Mode applicable to all PDP Contexts within the activated PDP Address/APN pair. If only QoS parameter ARP is modified Steps 4, 5 may be skipped unless ISR is activated. If the procedure is performed without steps 4 and 5 and location retrieval is requested and the UE is PMM_CONNECTED and unless the SGSN is configured not to retrieve CGI/SAI from the RNC under this condition, the SGSN uses the Location Reporting Procedure described in clause 12.7.5 to retrieve the SAI from the RNC. The SGSN may include an indication whether the traffic of this PDP context is allowed to be offloaded to WLAN as described in clause 5.3.21.

The MS should accept the PDP context modification requested by the network if it is capable of supporting any modified QoS Negotiated as well as any modified TFT. For a successful modification the MS acknowledges by returning a Modify PDP Context Accept message. If the MS is incapable of accepting a new QoS Negotiated it shall instead de-activate the PDP context with the PDP Context Deactivation Initiated by MS procedure. An E-UTRAN capable MS shall set its TIN to "P-TMSI" if the modified PDP context was established before ISR activation. If the BCM parameter is not included in the Modify PDP Context Request message then the MS shall set the Bearer Control Mode to 'MS_only' for the PDP Address/APN pair (see clause 9.2).

Upon receipt of the Modify PDP Context Accept message, or upon completion of the RAB modification procedure, the SGSN returns an Update PDP Context Response (TEID, QoS Negotiated, CGI/SAI) message to the GGSN. If the SGSN receives a Deactivate PDP Context Request message, it shall instead follow the PDP Context Deactivation Initiated by MS procedure. The SGSN includes the last known location information. If the Update PDP Context Request message is rejected with a cause indicating that the MS is temporarily not reachable due to power saving, then the GGSN re-attempts the same procedure after it receives the indication that the is UE available for end to end signalling in a subsequent PDP Context Modification procedure.

The P-GW sends the Update Bearer Request (TEID, EPS Bearer Identity, EPS Bearer QoS, APN-AMBR, Prohibit Payload Compression, MS Info Change Reporting Action, CSG Information Reporting Action, TFT, Protocol Configuration Options, Retrieve Location) message to the S-GW. PDN Address Information is included if it was provided by the P-GW. The Prohibit Payload Compression indicates that the SGSN should negotiate no data compression for this EPS Bearer. The TFT is optional and included in order to add, modify or delete the TFT related to the PDP Context (in accordance with the requirements in clauses 9.2.0 and 15.3.0). Protocol Configuration Options optional EPS Bearer parameters that the P-GW/PCRF may transfer to the MS. The PDN-GW may have interacted with PCRF beforehand (refer to TS 23.203). "Retrieve Location" is indicated if requested by the PCRF. If the MS is in IDLE state and extended idle mode DRX is enabled for the MS, the SGSN will trigger Network Initiated Service Request Procedure from step 2 (which is specified in clause 6.12.2) and start a timer which is configured to a value smaller than the GTP re-transmission timer. If the SGSN receives no response from the MS before the timer expires, the SGSN sends an Update Bearer Response with a rejection cause indicating that MS is temporarily not reachable due to power saving and then sets the internal flag Pending Network Initiated PDN Connection Signalling. The rejection is forwarded by the Serving GW to the PDN-GW.

If ISR is activated and UE is in PMM_IDLE or STANDBY state, S-GW shall first trigger the Network Triggered Service Request procedure (refer to TS 23.401). The S-GW sends the Update Bearer Request (TEID, EPS Bearer Identity, EPS Bearer QoS, APN-AMBR, Prohibit Payload Compression, MS Info Change Reporting Action, CSG Information Reporting Action, TFT, Protocol Configuration Options, Retrieve Location) message to the SGSN. If the "Higher bit rates than 16 Mbps flag" in the MM Context of the UE is set to "not allowed", then the S4-SGSN shall, for non-GBR bearers, restrict the MBR sent to the UE to within 16 Mbps.

The SGSN acknowledges the bearer modification to the S-GW by sending an Update Bearer Response (EPS Bearer Identity, User Location Information) message to the S-GW. If there is no signalling with the MS, e.g. because the MS is in PMM_IDLE or STANDBY state, the SGSN provides the last known location information.

The S-GW acknowledges the bearer modification to the P-GW by sending an Update Bearer Response (EPS Bearer Identity, User Location Information) message. The PDN-GW may interact with PCRF (refer to TS 23.203). The P-GW may interact with PCRF (refer to TS 23.203, e.g. to deliver User Location Information and/or UE Time Zone Information if it was requested by the PRCF. If the bearer modification is rejected with a cause indicating that the MS is temporarily not reachable due to power saving, then the PDN-GW re-attempts the same procedure after it receives the indication that MS is available for end to end signalling in the subsequent Modify Bearer Request message.