5.1 MMTel charging principles

32.2753GPPCharging managementMultiMedia Telephony (MMTel) chargingRelease 17Telecommunication managementTS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

5.1.0 Introduction

The MMTel charging encompasses the Multimedia telephony service (e.g. multimedia conversational communications between two or more users, with speech as a typical usage, and also others combinations of media) together with the associated supplementary services charging aspects.

Every Supplementary services described in TS 22.173 [200] are subject to be involved in MMTel charging function description.

MMTel service and supplementary services charging function focuses on charging information provided by the CTFs supporting MMtel specific service charging: calling user identification, called user identification, media component characteristics and usage (speech only, speech with other component, add/retrieve components..), supplementary services applied. It enables to apply different flexible charging based on supplementary service type and options.

All the CTFs supporting MMtel specific service charging (AS) pertain to IMS domain, and as explained in TS 32.260 [20], it is possible to correlate session/transaction related charging data generated from these different Nodes (AS), and others IMS Nodes involved in the session used for MMTel service handling , based on IMS Charging Identifier (ICID).

For AS(s) providing MMTel specific service and supplementary services, the "OneChargingSession" option, as described in TS 32.260 [20] can be applied, when acting as a B2BUA with IMS Charging Identifier (ICID) preserved between dialogs.

5.1.1 Supplementary services invocation

5.1.1.1 OIP charging

The Originating Identification Presentation (OIP) service provides the terminating user with the possibility of receiving trusted (i.e. network‑provided) identity information in order to identify the originating user.

5.1.1.2 OIR charging

The Originating Identification Restriction (OIR) service is a service offered to the originating user. It restricts presentation of the originating user’s identity information to the terminating user.

5.1.1.3 TIP charging

The Terminating Identification Presentation (TIP) service provides the originating party with the possibility of receiving trusted information in order to identify the terminating party.

5.1.1.4 TIR charging

The Terminating Identification Restriction (TIR) is a service offered to the terminating party which enables the terminating party to prevent presentation of the terminating identity information to originating party.

5.1.1.5 HOLD charging

The Communication Hold supplementary service enables a user to suspend the media stream(s) of an established IP multimedia session, and resume the media stream(s) at a later time.

The charged parties may be any of the Hold parties. These roles are:

– Calling Party;

– Called Party;

Editor’s note: When one of the parties originates a new call to a third party and the new call overbooks the bearer resource reserved by the held call, overbooking may be taken into account in charging. The solution for that is FFS.

5.1.1.6 CB charging

The Communication Barring (CB) service offers the following services:

– The Incoming Communications Barring (ICB) is a service that rejects incoming communications that fulfil certain provisioned or configured conditions on behalf of the terminating user.

– The Anonymous Communication Rejection (ACR) is a particular case of the ICB service, that allows barring of incoming communications from an anonymous originator on behalf of the terminating user.

– The Outgoing Communication Barring (OCB) is a service that rejects outgoing communications that fulfil certain provisioned or configured conditions on behalf of the originating user.

5.1.1.7 CDIV charging

The Communications Diversion (CDIV) services enables the diverting user, to divert the communications addressed to the diverting user to another destination.

There are three actors active in a CDIV service of one diversion with the following roles:

– Diverting user; the party that initiates the diversion of an incoming communication;

– Originating user; the party which has initiated the communication and that stays in the communication which is diverted;

– Diverted to user;

In case there is another diversion, the user that was first the diverting user (user B), is the originating user in the second diversion. The diverted to user of the first diversion (user C) is the diverting user of the second diversion.

The charging of the diverting user for the B-C leg is measured by the MMTel AS handling the CDIV service, i.e. by the MMTel AS of the diverting user (user B). For the diverting user a separate charging dialog (online and/or offline charging) is needed. Charging of the originating and the terminating user (user C) is done in alignment with the TS 32.260 [20].

Typically the diverting user is charged for the forwarded leg (B-C leg), however, normal roaming charging principles apply for the diverted to user also in case of communication diversion. If there is another diversion, the user that performs the second diversion (user C) is charged (typically) for the new forwarded leg (C-D leg).

Charging at the S-CSCF is done in alignment with the TS 32.260 [20] but the S-CSCF has no knowledge of the CDIV service.

5.1.1.8 CW charging

The Communication Waiting (CW) service enables the application server to indicate to the subscriber, that there is at least one new communication is requested, and that no resources are available for that incoming communication. The user has then the choice of accepting, rejecting or ignoring the incoming communication. The maximum number of communications that may be waiting is a service provider option. If the current number of communications waiting is equal to the maximum, then any new attempted incoming communication request shall be rejected with a busy cause.

5.1.1.9 ECT charging

The Explicit Communication Transfer (ECT) service provides a party involved in a communication to transfer that communication to a third party.

There are three actors active in a transfer, they are acting in the following roles:

– Transferor: the party that initiates the transfer of the active communication that it has with the Transferee;

– Transferee: the party which stays in the communication which is transferred;

– transfer target: the party which the communication is transferred to and which replaces the Transferor in the communication.

The charging of the Transferor is measured by the MMTel AS handling the ECT service for the Transferor.
The charging of the Transferee is measured by the MMTel AS handling the ECT service for the Transferee.

5.1.1.10 MWI charging

The Message Waiting Indication (MWI) service enables the application server to indicate to the subscriber, that there is at least one message waiting. The indication is delivered to the subscriber’s UE after successful subscription to the MWI service as described in the present document.

5.1.1.11 CONF charging

The Conference (CONF) service enables a user to participate in and control a simultaneous communication involving a number of users.

CONF Charging for the conference owner could be based on:

– establishment of the conference;

– number of participants;

– duration.

CONF Charging for the conference participants could be based on:

– duration.

The charging of the conference owners and participants is measured by the SIP AS and MRFC handling conference service. For each participant (call leg) a separate charging dialog at the SIP AS is needed.

5.1.1.12 CCBS charging

The Completion of Communication to Busy Subscriber (CCBS) service enables user A, encountering a busy destination B, to have the communication completed without the user having to manually initiate a new communication attempt when the destination B becomes not busy.

When user A requests the CCBS supplementary service, the network monitors for destination B becoming free again.

When destination B becomes free again, the network waits a short time in order to allow the resources to be re-used for originating a communication. If the resources are not re-used by destination B within this time, the network automatically recalls user A.

When user A accepts the CCBS recall, the network automatically generates a CCBS call to destination B.

5.1.1.13 CCNR charging

The Completion of Communications on No Reply (CCNR) service enables user A, encountering a destination B which does not answer the communication (No Reply), to have the communication completed without the user having to manually initiate a new communication attempt when the destination becomes not busy after having initiated and completed a new communication.

When user A encounters a destination B which does not answer the communication (No Reply), user A can request the CCNR supplementary service.

When user A requests the CCNR supplementary service, the network monitors for destination B becoming not busy after having initiated and completed a new communication.

When destination B becomes not busy after having initiated and completed a new communication, the network waits a short time (as defined by the destination B idle guard timer) in order to allow the resources to be reused for originating a communication. If the resources are not reused by destination B within this time, the network automatically recalls user A.

When user A accepts the CCNR recall, then the network automatically generates a CCNR call to destination B.

5.1.1.14 FA charging

Flexible Alerting (FA) causes a call to a "Pilot Identity" to branch the call into several legs to alert several termination addresses (FA group members) simultaneously.
Additional calls may be delivered to the FA Pilot Identity at any time.
The first leg to be answered is connected to the calling party. The other call legs are abandoned.

The FA group, identified by the "Pilot Identity" consists of a list of FA group members alerted through their the public addressable identity.

5.1.1.15 MCID charging

The Malicious Communication Identification (MCID) service enables an incoming communication to be identified as malicious and registered.

The Network shall register the communication related information (such as Terminating Identity Information, Originator Identity Information, Local Time and Date…), which shall be kept under Network Operator’s control (i.e. not available to the terminating entity nor the originating entity).

This service has two modes: permanent mode and temporary mode. The permanent mode is active for all incoming communications, and the temporary mode is active only for the incoming communications declared by the served user.

The MCID service can be invoked during the active phase of the communication, or after the active phase for a limited period (but never after communication termination) by the served user, or, automatically invoked during the alerting phase.

5.1.1.16 CAT charging

The Customized Alerting Tone Service (CAT) service is an operator specific service by which an operator enables the subscriber to customize the alerting tone which is played to the calling party.

5.1.1.17 CUG charging

The Closed User Group (CUG) service enables users to form groups of members, whose communication profile is restricted for incoming and outgoing communications. Members of a specific CUG can communicate among themselves but not, in general, with users outside the group.

Specific CUG members can have additional capabilities that allow them to initiate outgoing communications to users outside the group, and/or to accept incoming communications from users outside the group. Specific CUG members can have additional restrictions that prevent outgoing communications to other members of the CUG, or prevent incoming communications from other members of the CUG.

A specific user may be a member of one or more CUGs.

5.1.1.18 PNM charging

The Personal Network Management (PNM) service allows a user to manage his UEs in regard to terminating services according to preferences set by the user, capabilities and availabilities of devices. Charging for the "PN UE redirection" functionality of the defined PNM service, is considered in the scope of MMTel supplementary service charging, and applies to the active UE the terminating services are delivered to.

5.1.1.19 CRS charging

The Customized Ringing Signal (CRS) service is an operator specific service by which an operator enables the subscriber to customize the ringing signal which is played to the called party.

5.1.1.20 Reverse charging

The Reverse charging at communication set up time service allows the terminating party to be charged for the entire communication. The service, requested by the originating party at communication set up time, is explicitly indicated to the terminating party so he can accept or deny the reverse charge communication request.

Editor’s Note: There is no stage 3 description for Reverse Charging in this Release: FFS.

5.1.1.21 AoC charging

The Advice of Charge (AoC) service allows the served user to be provided with MMTel service charging information related to:

– AoC at communication set-up time (AoC-S);

– AoC during the communication (AoC-D);

– AoC at the end of the communication (AoC-E).

5.1.2 Supplementary services management by the user

When an IMS supplementary service control can be provided to the UE as a subscription option, every action performed by the user for this service (Provision/Withdrawal, Registration/Erasure, Activation/Deactivation, interrogation) may be subject to produce charging information, but this aspect is out of the scope of the present document.

5.1.3 OCS-provided announcements for MMTel service

During an online charging session from an AS providing MMTel service and supplementary services, the OCS may utilize the Announcement service specified in TS 32.281 [41] to request this AS to render video or audio announcements to a subscriber involved in the MMTel service/supplementary services.

Further details on announcements interaction with MMTel supplementary services are specified in clause 5.3.2.1

5.1.4 CHF provided announcements for MMTel service

During converged charging sessions from an AS providing MMTel service and supplementary services, the CHF may utilize the Announcement service specified in TS 32.281 [41] to request this AS to render video or audio announcements to a subscriber involved in the MMTel service/supplementary services.

Further details on announcements interaction with MMTel supplementary services are specified in clause 5.4.2.