5 CP data transfer domain charging principles and scenarios
32.2533GPPCharging managementControl Plane (CP) data transfer domain chargingRelease 17Telecommunication managementTS
5.1 CP data transfer domain charging principles
The following are high level charging requirements for Control Plane data transfer, derived from requirements in TS 23.682 [243]:
– Every PDN connection shall be assigned a unique identity number for billing purposes. (i.e. the Charging Id);
– CPCN shall be capable of identifying NIDD submission request events in mobile originated (MO) and mobile terminated (MT) direction;
– CPCN shall be capable of identifying data volume per NIDD submission request;
– CPCN shall be capable of handling the Charging Characteristics;
– CPCN shall be able, based on operator configuration, to collect charging information for the PDN connection in the same PLMN using offline charging;
– PDN connection in a different PLMN using offline charging.
For the PDN connection, the CPCN shall collect the following information:
– usage of the radio interface: the charging information shall describe the amount of data transmitted in MO and MT directions using Control Plane CIoT EPS Optimisation per each NIDD submission per RAT type and authorized Serving PLMN/APN Rate controls;
– usage duration: duration of PDN connection is counted as the time interval from PDN connection activation to PDN connection deactivation;
– destination and source: the charging information shall provide the user identity (IMSI) and subscriber equipment number (IMEISV) used by the subscriber for the PDN connection and the destination as determined by the Access Point Name (APN) and SCEF address;
– usage of the external data networks: the charging information shall describe the amount of data sent and received to and from the external data network with the corresponding time stamp per each NIDD submission;
– location of MS/UE: HPLMN, VPLMN, plus optional higher-accuracy location information.
5.2 CP data transfer domain offline charging scenarios
5.2.1 Basic principles
If charging is supported by an CPCN (SCEF, IWK-SCEF, or optionally MME), it shall be able to collect charging information per user per PDN connection, and per Non-IP Data Delivery submission in both originating and terminating directions with associated volume counts.
The user is identified by the IMSI, while the PDN connection to the SCEF can be determined by a unique identifier generated by the SCEF when creating a PDN connection. This identifier is forwarded to the MME so as to allow correlation of MME PDN connection CDRs if any, with the matching SCEF CDRs in the BD. In roaming case, this identifier is forwarded to the IWK-SCEF so as to allow correlation between IWK-SCEF PDN connection CDRs in VPLMN and SCEF PDN connection CDRs in the HPLMN.
The following chargeable events are defined for Control Plane data transfer charging for all CPCNs:
– Start of PDN connection. Upon encountering this event, a CDR for this PDN connection is created;
– End of PDN connection. Upon encountering this event, the CDR is closed;
– NIDD submission request. Upon encountering this event, the NIDD submission with associated volume count is added to the CDR;
– Mobility to a new MME. Upon encountering this event, the CDR is closed. In SCEF and IWK-SCEF, a new one is opened if the PDN connection is still active. In the new MME the CDR is created;
– Serving PLMN Rate Control change. This event closes the CDR, and a new one is opened if the PDN connection is still active.
– APN PLMN Rate Control change in SCEF. This event is applicable for the SCEF only. This event closes the CDR, and a new one is opened if the PDN connection is still active.
– PLMN change. This event closes the CDR. In the SCEF, a new one is opened if the PDN connection is still active;
– Intersystem change (e.g. change of RAT type). This event closes the CDR, and a new one is opened if the PDN connection is still active.
NOTE: Inter-RAT mobility between NB-IoT and other RAT is not supported in this release.
– Expiry of an operator configured time limit per PDN connection. This event closes the CDR, and a new one is opened if the PDN connection is still active;
– Expiry of an operator configured data volume limit per PDN connection. This event closes the CDR, and a new one is opened if the PDN connection is still active;
– Expiry of an operator configured NIDD submissions limit per PDN connection. This event closes the CDR, and a new one is opened if the PDN connection is still active.
Management intervention may also force trigger a chargeable event.
5.2.2 Rf message flows
5.2.2.1 Triggers for charging events from CPCN
When a charging event is reported to the CDF, it includes details such as user identity, Charging Id, APN, SCEF address, MME address, and in roaming scenario, IWK-SCEF address. NIDD submissions charging information, including associated volume count are reported with corresponding charging events to the CDF.
The Charging Characteristics are also used to set the coherent chargeable event conditions (e.g. time/volume limits that trigger CDR generation or information addition). The Charging Characteristics is provided by the HSS to the CPCNs as part of the subscription information. Further details about Charging Characteristics are defined in Annex A.
When offline charging is activated for CP data transfer in CPCN, it shall be possible to define separate trigger conditions values per Charging Characteristics profile for the following triggers:
– data volume limit;
– time (duration limit);
– maximum number of NIDD submissions.
If, according to the Charging Characteristics profile, offline charging is activated for CP data transfer in CPCN, Charging Data Request [Start] is sent at PDN connection creation.
Charging Data Request [Stop] is sent at PDN connection release.
Charging Data Request [Interim] is sent during the lifetime of the PDN connection, upon occurrence of the trigger conditions specified in Table 5.2.2.1.1.
Table 5.2.2.1.1: Triggers for Charging Data Request from CPCN
|
Message |
Trigger Conditions |
|
Charging Data Request [Start] |
PDN connection creation |
|
Charging Data Request [Interim] |
NIDD submit response receipt to NIDD submit request Serving PLMN Rate Control change RAT type change Expiry of time limit |
|
Charging Data Request [Stop] |
PDN connection release |
When applicable per Charging Characteristics, "data volume limit" and "maximum number of NIDD submissions" are trigger conditions met upon one particular "NIDD submit response to NIDD submit request". They shall be reported along with the Charging Data Request [Interim] triggered by this "NIDD submit response to NIDD submit request" within Change Condition under PS information of Service Information.
NOTE: Inter-RAT mobility between NB-IoT and other RAT is not supported in this release.
5.2.2.2 SCEF specific triggers for charging events
The subclause 5.2.2.1 is applicable for CP data transfer collection of charging information and triggers for SCEF CPCN.
Table 5.2.2.2.1 identifies the additional trigger conditions applicable to SCEF.
Table 5.2.2.2.1: SCEF specific triggers for Charging Data Request
|
Message |
Trigger Conditions |
|
Charging Data Request [Interim] |
NIDD submission response sending MME Change APN Rate Control change PLMN Change |
5.2.2.3 IWF-SCEF specific triggers for charging events
The subclause 5.2.2.1 is applicable for CP data transfer collection of charging information and triggers for IWK-SCEF CPCN.
Table 5.2.2.3.1 identifies the additional trigger conditions applicable to IWK-SCEF.
Table 5.2.2.3.1: IWF-SCEF specific triggers for Charging Data Request
|
Message |
Trigger Conditions |
|
Charging Data Request [Interim] |
NIDD submission response sending Change Serving PLMN Rate Control change |
|
Charging Data Request [Stop] |
PLMN Change |
5.2.2.4 MME specific triggers for charging events
When optional CP data transfer offline charging is supported by the MME, the subclause 5.2.2.1 is applicable for CP data transfer collection of charging information and triggers for MME CPCN.
Table 5.2.2.4.1 identifies the additional trigger conditions applicable to MME.
Table 5.2.2.4.1: MME specific triggers for Charging Data Request
|
Message |
Trigger Conditions |
|
Charging Data Request [Start] |
MME Change from old MME |
|
Charging Data Request [Interim] |
NIDD delivery to the UE NIDD delivery from the UE error |
|
Charging Data Request [Stop] |
MME Change to new MME PLMN Change |
5.2.3 CDR generation
5.2.3.1 Introduction
For each of the CPCNs (SCEF, IWK-SCEF and MME), a CP data transfer CDR is generated for subsequent transfer to the Charging Gateway Function (CGF).
The following clauses describe the trigger conditions for these CP data transfer CDRs creation, update and closure.
5.2.3.2 Triggers for CPDT-SCE-CDR creation and closure
5.2.3.2.1 General
A CPDT-SCE-CDR is used to collect charging information related to Control Plane data transfer offline charging from a SCEF.
A CPDT-SCE-CDR shall be opened at PDN connection start, and shall be closed as described in subclause 5.2.3.2.3.
Charging information shall be added to a CPDT-SCE-CDR as described in subclause 5.2.3.2.2.
5.2.3.2.2 Triggers for CPDT-SCE-CDR charging information addition
The "List of NIDD submissions" attributes of the CPDT-SCE-CDR consists of a set of containers. Each container identifies a NIDD submission and shall be added to the "List of NIDD submissions" per table 5.2.3.2.2.1 trigger conditions. Details of the container are defined in clause 6.1.3.4.
Table 5.2.3.2.2.1 identifies which conditions are supported to trigger CPDT-SCE-CDR charging information addition.
Table 5.2.3.2.2.1: Triggers for CPDT-SCE-CDR charging information addition
|
Trigger Conditions |
Description/Behaviour |
|
NIDD submission response receipt |
On receipt of NIDD submit response to NIDD submit request, the NIDD submission container shall be added to the CPDT-SCE-CDR. |
|
NIDD submission response sending |
On sending of NIDD submit response to received NIDD submit request, the NIDD submission container shall be added to the CPDT-SCE-CDR. |
|
NIDD submission timeout |
On timer expiry due to no NIDD submit response to a NIDD submit request, the NIDD submission container shall be added to the CPDT-SCE-CDR. |
5.2.3.2.3 Triggers for CPDT-SCE-CDR closure
The CPDT-SCE-CDR shall be closed on encountering any of the following trigger conditions identified in Table 5.2.3.2.3.1:
Table 5.2.3.2.3.1: Triggers for CPDT-SCE-CDR closure
|
Closure Conditions |
Description/Behaviour |
|
PDN connection release. |
PDN connection release shall result in the CDR being closed. The trigger condition covers: – termination of PDN connection; – any abnormal release. |
|
Partial Record Reason |
Partial Record Reason, shall result in the CDR being closed. The trigger condition covers: – data volume limit; – time (duration limit); – maximum number of NIDD submissions; – MME change; – Serving PLMN Rate Control change; – APN Rate Control change; – PLMN change; – radio access technology change (RAT Type); – Management intervention. |
The Partial Record generation trigger thresholds are those associated with the Charging Characteristics.
The Partial Record generation trigger thresholds are SCEF configuration parameters defined per Charging Characteristics profile by the operator through OAM&P means, as specified in Annex A.
In the event that the CPDT-SCE-CDR is closed and the PDN connection remains active, a further CPDT-SCE-CDR is opened with an incremented Sequence Number.
NOTE: Inter-RAT mobility between NB-IoT and other RAT is not supported in this release.
5.2.3.3 Triggers for CPDT-SNN-CDR creation and closure – IWK-SCEF
5.2.3.3.1 General
A CPDT-SNN-CDR is used to collect charging information related to Control Plane data transfer offline charging from a IWK-SCEF.
A CPDT-SNN-CDR shall be opened at PDN connection start for this IWK-SCEF, i.e. upon PDN connection creation and mobility towards the new IWK-SCEF (upon PLMN change).
A CPDT-SNN-CDR shall be closed as described in subclause 5.2.3.3.3.
Charging information shall be added to a CPDT-SNN-CDR as described in subclause 5.2.3.3.2.
5.2.3.3.2 Triggers for CPDT-SNN-CDR charging information addition – IWK-SCEF
The "List of NIDD submissions" attributes of the CPDT-SNN-CDR consists of a set of containers. Each container identifies a NIDD submission and shall be added to the "List of NIDD submissions" per table 5.2.3.3.2.1 trigger conditions. Details of the container are defined in clause 6.1.3.4.
Table 5.2.3.3.2.1 identifies which conditions are supported to trigger CPDT-SNN-CDR charging information addition.
Table 5.2.3.3.2.1: Triggers for CPDT-SNN-CDR charging information addition – IWK-SCEF
|
Trigger Conditions |
Description/Behaviour |
|
NIDD submission response receipt |
On receipt of NIDD submit response to NIDD submit request, the NIDD submission container shall be added to the CPDT-SNN-CDR. |
|
NIDD submission response sending |
On sending of NIDD submit response to received NIDD submit request, the NIDD submission container shall be added to the CPDT-SCE-CDR. |
5.2.3.3.3 Triggers for CPDT-SNN-CDR closure – IWK-SCEF
The CPDT-SNN-CDR shall be closed on encountering any of the following trigger conditions identified in Table 5.2.3.3.3.1:
Table 5.2.3.3.3.1: Triggers for CPDT-SNN-CDR closure- IWK-SCEF
|
Closure Conditions |
Description/Behaviour |
|
PDN connection release. |
PDN connection release shall result in the CDR being closed. The trigger condition covers: – termination of PDN connection; – PLMN Change; – any abnormal release. |
|
Partial Record Reason |
Partial Record Reason, shall result in the CDR being closed. The trigger condition covers: – data volume limit; – time (duration limit); – maximum number of NIDD submissions; – MME change; – Serving PLMN Rate Control change; – radio access technology change (RAT Type); – Management intervention. |
The Partial Record generation trigger thresholds are those associated with the Charging Characteristics.
The Partial Record generation trigger thresholds are IWK-SCEF configuration parameters defined per Charging Characteristics profile by the operator through OAM&P means, as specified in Annex A.
In the event that the CPDT-SNN-CDR is closed and the PDN connection remains active, a further CPDT-SNN-CDR is opened with an incremented Sequence Number.
NOTE: Inter-RAT mobility between NB-IoT and other RAT is not supported in this release.
5.2.3.4 Triggers for CPDT-SNN-CDR creation and closure – MME
5.2.3.4.1 General
When supported, a CPDT-SNN-CDR is used to collect charging information related to Control Plane data transfer offline charging from a MME.
A CPDT-SNN-CDR shall be opened at PDN connection start for this MME, i.e. upon PDN connection creation and Mobility to this new MME.
A CPDT-SNN-CDR shall be closed as described in subclause 5.2.3.4.3.
Charging information shall be added to a CPDT-SNN-CDR as described in subclause 5.2.3.4.2.
5.2.3.4.2 Triggers for CPDT-SNN-CDR charging information addition – MME
The "List of NIDD submissions" attributes of the CPDT-SNN-CDR consists of a set of containers. Each container identifies a NIDD submission and shall be added to the "List of NIDD submissions" per table 5.2.3.4.2.1 trigger conditions. Details of the container are defined in clause 6.1.3.4.
Table 5.2.3.4.2.1 identifies which conditions are supported to trigger CPDT-SNN-CDR charging information addition.
Table 5.2.3.4.2.1: Triggers for CPDT-SNN-CDR charging information addition – MME
|
Trigger Conditions |
Description/Behaviour |
|
NIDD submission response receipt |
On receipt of NIDD submit response to NIDD submit request, the NIDD submission container shall be added to the CPDT-SNN-CDR. |
|
NIDD delivery to the UE |
On NIDD delivery to the UE, the NIDD submission container shall be added to the CPDT-SNN-CDR. |
|
NIDD submission timeout |
On timer expiry due to no NIDD submit response to a NIDD submit request, the NIDD submission container shall be added to the CPDT-SCE-CDR. |
|
NIDD delivery from the UE error |
Error cases on receipt of NIDD delivery from the UE. |
5.2.3.4.3 Triggers for CPDT-SNN-CDR closure – MME
The CPDT-SNN-CDR shall be closed on encountering any of the following trigger conditions identified in Table 5.2.3.4.3.1:
Table 5.2.3.4.3.1: Triggers for CPDT-SNN-CDR closure — MME
|
Closure Conditions |
Description/Behaviour |
|
PDN connection release. |
PDN connection release shall result in the CDR being closed. The trigger condition covers: – termination of PDN connection; – MME Change; – any abnormal release. |
|
Partial Record Reason |
Partial Record Reason, shall result in the CDR being closed. The trigger condition covers: – data volume limit; – time (duration limit); – maximum number of NIDD submissions; – Serving PLMN Rate Control change; – radio access technology change (RAT Type); – Management intervention. |
The Partial Record generation trigger thresholds are those associated with the Charging Characteristics.
The Partial Record generation trigger thresholds are MME configuration parameters defined per Charging Characteristics profile by the operator through OAM&P means, as specified in Annex A.
In the event that the CPDT-SNN-CDR is closed and the PDN connection remains active, a further CPDT-SNN-CDR is opened with an incremented Sequence Number.
NOTE: Inter-RAT mobility between NB-IoT and other RAT is not supported in this release.
5.2.4 Ga record transfer flows
Details of the Ga protocol application are specified in TS 32.295 [54].
5.2.5 Bx CDR file transfer
Details of the Bx protocol application are specified in TS 32.297 [52].
5.3 CP data transfer domain online charging scenarios
5.3.1 Basic principles
Not specified in the present document.
5.3.2 Ro message flows
Not specified in the present document.