5.4 IMS converged charging scenarios
32.2603GPPCharging managementIP Multimedia Subsystem (IMS) chargingRelease 17Telecommunication managementTS
5.4.1 Basic scenario
The Charging Data Request and Charging Data Response are exchanged between the IMS Nodes and the CHF using Nchf, based on either IEC, PEC, ECUR or SCUR scenarios specified in TS 32.290 [45].
Converged charging uses centralized or decentralized unit determination and centralized rating scenarios for event based converged charging as specified in TS 32.290 [45].
The contents and purpose of each charging event that triggers interaction with CHF, as well as the chargeable events that trigger them, are described in the following clauses 5.4.3.
A detailed formal description of the converged charging parameters defined in the present document is to be found in TS 32.291 [46].
A detailed formal description of the CDR parameters defined in the present document is to be found in TS 32.298 [51].
5.4.2 CHF and charging service selection
When use of Nchf interface is determined by the IMS Node, the CHF address(s) with possible associated CHF instance ID(s) and/or CHF set ID(s) can be selected from IMS signalling as per clause 5.1.1 , using NRF or can be configured locally.
Each IMS Node of the IMS converged charging architecture is configured with "converged charging" method or "offline only charging" method, except the IMS-GWF for which only the "converged charging" method is valid. When configured with "offline only charging" method, the Nchf converged charging service is the default one to be used by the IMS Node, unless based on Operator policy the alternative Nchf offline only service has to be used.
5.4.3 Applicable triggers for IMS charging
The IMS nodes for which SIP method a charging Data Request is sent shall be operator configurable. The tables below describe all possible Charging Data Requests that might be sent from IMS nodes.
The generation of a Charging Data Request message by the IMS nodes in response to a particular "triggering SIP method" shall be operator configurable (enable or disable).
Table 5.4.3.1: Default Trigger conditions in IMS Node
|
Trigger Conditions |
Trigger level |
Default category |
CHF allowed to change category |
CHF allowed to enable and disable |
Message when "immediate reporting" category |
|---|---|---|---|---|---|
|
SIP INVITE |
– |
Immediate |
Not Applicable |
Not Applicable |
SCUR: Charging Data Request [Initial] |
|
SIP NOTIFY |
– |
Immediate |
Not Applicable |
Not Applicable |
ECUR: Charging Data Request [Initial] IEC: Charging Data Request [Event] |
|
SIP MESSAGE |
– |
Immediate |
Not Applicable |
Not Applicable |
|
|
SIP REGISTER |
– |
Immediate |
Not Applicable |
Not Applicable |
|
|
SIP SUBSCRIBE |
– |
Immediate |
Not Applicable |
Not Applicable |
|
|
SIP REFER |
– |
Immediate |
Not Applicable |
Not Applicable |
|
|
SIP PUBLISH |
– |
Immediate |
Not Applicable |
Not Applicable |
|
|
Change of charging conditions |
SCUR: Charging Data Request [Update] |
||||
|
SIP RE-INVITE or UPDATE (e.g. change in media components, terminating identity change) |
– |
Immediate |
No |
No |
|
|
SIP 2xx acknowledging a SIP INVITE, RE-INVITE or UPDATE (e.g. change in media components) |
– |
Immediate |
No |
No |
|
|
SIP 1xx provisional response, mid-dialog requests, mid-dialog responses and SIP INFO embedding RTTI XML body |
– |
Immediate |
No |
No |
|
|
SIP 4xx, 5xx or 6xx response, indicating an unsuccessful SIP RE-INVITE or UPDATE |
– |
Immediate |
No |
No |
|
|
Any other SIP message during a SIP session, that allows the SIP session to continue |
– |
Immediate |
Yes |
No |
|
|
CHF limit |
|||||
|
Expiry of time limit |
– |
Immediate |
No |
Yes |
|
|
Expiry of limit of number of charging condition changes |
– |
Immediate |
No |
Yes |
|
|
Quota management |
|||||
|
Time threshold reached |
– |
Immediate |
No |
Yes |
|
|
Time quota exhausted |
– |
Immediate |
No |
Yes |
|
|
Unit quota exhausted |
– |
Immediate |
No |
Yes |
|
|
Expiry of quota validity time |
– |
Immediate |
No |
Yes |
|
|
Expiry of quota holding time |
– |
Immediate |
No |
Yes |
|
|
Re-authorization request by CHF |
– |
Immediate |
No |
Yes |
|
|
Other |
|||||
|
Management intervention |
– |
Immediate |
No |
No |
|
|
SIP BYE message |
– |
Immediate |
Not Applicable |
Not Applicable |
SCUR: Charging Data Request [Termination] |
|
SIP 2xx acknowledging a SIP BYE |
– |
Immediate |
Not Applicable |
Not Applicable |
|
|
Aborting a SIP session set-up procedure, using an internal trigger or a SIP CANCEL |
– |
Immediate |
Not Applicable |
Not Applicable |
|
|
SIP 3xx final or redirection response |
– |
Immediate |
Not Applicable |
Not Applicable |
|
|
SIP 2xx acknowledging non-session related SIP messages |
– |
Immediate |
Not Applicable |
Not Applicable |
ECUR: Charging Data Request [Termination] |
|
Deregistration |
– |
Immediate |
Not Applicable |
Not Applicable |
|
|
SIP 4xx, 5xx or 6xx final response, indicating an unsuccessful procedure |
– |
Immediate |
Not Applicable |
Not Applicable |
SCUR: Charging Data Request [Termination] ECUR: Charging Data Request [Termination] PEC: Charging Data Request [Event] |
For converged charging, the following details of chargeable events and corresponding actions in the IMS nodes are defined in Table 5.4.3.2:
Table 5.4.3.2: Chargeable events and their related actions in IMS nodes
|
Chargeable event |
Conditions |
IMS node action |
|---|---|---|
|
SIP INVITE |
SCUR: Charging Data Request [Initial] with a possible request quota for later use |
|
|
SIP NOTIFY |
ECUR: Charging Data Request [Initial] with a possible request quota for later use IEC: Charging Data Request [Event] |
|
|
SIP MESSAGE |
ECUR: Charging Data Request [Initial] with a possible request quota for later use IEC: Charging Data Request [Event] |
|
|
SIP REGISTER |
ECUR: Charging Data Request [Initial] with a possible request quota for later use IEC: Charging Data Request [Event] |
|
|
SIP SUBSCRIBE |
ECUR: Charging Data Request [Initial] with a possible request quota for later use IEC: Charging Data Request [Event] |
|
|
SIP REFER |
ECUR: Charging Data Request [Initial] with a possible request quota for later use IEC: Charging Data Request [Event] |
|
|
SIP PUBLISH |
ECUR: Charging Data Request [Initial] with a possible request quota for later use IEC: Charging Data Request [Event] |
|
|
SIP RE-INVITE or UPDATE (e.g. change in media components, terminating identity change) |
SCUR: Charging Data Request [Update] with a request quota with a possible amount of quota |
|
|
SIP 2xx acknowledging a SIP INVITE, RE-INVITE or UPDATE (e.g. change in media components) |
SCUR: Charging Data Request [Update] with a request quota with a possible amount of quota |
|
|
SIP 1xx provisional response, mid-dialog requests, mid-dialog responses and SIP INFO embedding RTTI XML body |
SCUR: Charging Data Request [Update] with a request quota with a possible amount of quota |
|
|
SIP 4xx, 5xx or 6xx response, indicating an unsuccessful SIP RE-INVITE or UPDATE |
SCUR: Charging Data Request [Update] with a request quota with a possible amount of quota |
|
|
Any other SIP message during a SIP session, that allows the SIP session to continue |
Start new counts with time stamps for all active service data flows. |
|
|
If the corresponding trigger is enabled and the category is set to "immediate reporting" |
SCUR: Charging Data Request [Update] with a possible request quota. |
|
|
Expiry of time limit |
If the corresponding trigger is enabled |
SCUR: Charging Data Request [Update] with a possible request quota Close the counts and start new counts with time stamps |
|
Expiry of limit of number of charging condition changes |
If the corresponding trigger is enabled |
SCUR: Charging Data Request [Update] with a possible request quota Close the counts and start new counts with time stamps |
|
Time threshold reached |
If the corresponding trigger is enabled |
SCUR: Charging Data Request [Update] with a possible request quota Close the counts and start new counts with time stamps |
|
Time quota exhausted |
If the corresponding trigger is enabled |
SCUR: Charging Data Request [Update] with a possible request quota Close the counts and start new counts with time stamps |
|
Unit quota exhausted |
If the corresponding trigger is enabled |
SCUR: Charging Data Request [Update] with a possible request quota Close the counts and start new counts with time stamps |
|
Expiry of quota validity time |
If the corresponding trigger is enabled |
SCUR: Charging Data Request [Update] with a possible request quota Close the counts and start new counts with time stamps |
|
Expiry of quota holding time |
If the corresponding trigger is enabled |
SCUR: Charging Data Request [Update] with a possible request quota Close the counts and start new counts with time stamps |
|
Re-authorization request by CHF |
If the corresponding trigger is enabled |
SCUR: Charging Data Request [Update] with a possible request quota Close the counts and start new counts with time stamps |
|
Management intervention |
SCUR: Charging Data Request [Update] with a possible request quota Close the counts and start new counts with time stamps |
|
|
SIP BYE message, both normal and abnormal session termination cases |
SCUR: Charging Data Request [Termination] Close the counts with time stamps |
|
|
SIP 2xx acknowledging a SIP BYE |
If last user location information of originating/ terminating party is required |
SCUR:Charging Data Request [Termination] Close the counts with time stamps |
|
SIP 2xx acknowledging non-session related SIP messages |
ECUR: Charging Data Request [Termination] Close the counts with time stamps |
|
|
Aborting a SIP session set-up procedure, using an internal trigger or a SIP CANCEL |
SCUR: Charging Data Request [Termination] ECUR: Charging Data Request [Termination] Close the counts with time stamps |
|
|
Deregistration |
SCUR: Charging Data Request [Termination] ECUR: Charging Data Request [Termination] Close the counts with time stamps |
|
|
SIP 3xx final or redirection response |
SCUR: Charging Data Request [Termination] ECUR: Charging Data Request [Termination] Close the counts with time stamps |
|
|
SIP 4xx, 5xx or 6xx final response, indicating an unsuccessful procedure |
SCUR: Charging Data Request [Termination] ECUR: Charging Data Request [Termination] Close the counts with time stamps IEC: Charging Data Request [Event] PEC: Charging Data Request [Event] |
5.4.4 CDR generation
5.4.4.1 Introduction
The CHF CDRs for IMS charging are generated by the CHF to collect charging information that they subsequently transfer to the Charging Gateway Function (CGF).
The CHF shall support generating, opening updating and closing the CHF CDR as described in clause 5.4.4.2.
5.4.4.2 Triggers for CHF CDR
5.4.4.2.1 General
A IMS charging CHF CDR is used to collect charging information related to IMS chargeable events.
5.4.4.2.2 Triggers for CHF CDR generation
A CHF CDR is generated by the CHF for each received Charging Data Request [Event].
5.4.4.2.3 Triggers for CHF CDR opening
A CHF CDR shall be opened when the CHF receives Charging Data Request [Initial].
5.4.4.2.4 Triggers for CHF CDR update
A CHF CDR shall be updated when the CHF receives Charging Data Request [Update].
5.4.4.2.5 Triggers for CHF CDR closure
The CHF CDR shall be closed when the CHF receives Charging Data Request [Termination].
5.4.5 Ga record transfer flows
Details of the Ga protocol application are specified in TS 32.295 [54].
5.4.6 Bi CDR file transfer
Details of the Bi protocol application are specified in TS 32.297 [52].