WO2022033679A1

WO2022033679A1 - Mission critical push to talk private call initiation improvements

Info

Publication number: WO2022033679A1
Application number: PCT/EP2020/072686
Authority: WO
Inventors: Gábor ZSIGMOND; Szabolcs ZÁBÓ
Original assignee: Nokia Solutions And Networks Oy
Priority date: 2020-08-12
Filing date: 2020-08-12
Publication date: 2022-02-17

Abstract

There are provided measures for mission critical push to talk private call initiation improvements. Such measures exemplarily comprise, at a first mission critical push to talk server in a first mission critical push to talk system, receiving, from a first mission critical push to talk client, a private call request for a mission critical push to talk private call towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and deciding on a target of forwarding said private call request based on said functional alias information.

Description

Title

Mission critical push to talk private call initiation improvements

Field

The present invention relates to mission critical push to talk private call initiation improvements. More specifically, the present invention exemplarily relates to measures (including methods, apparatuses and computer program products) for realizing mission critical push to talk private call initiation improvements.

Background

The present specification generally relates to mission critical push to talk (MCPTT) and in particular to MCPTT private calls utilizing functional aliases.

MCPTT is a group communication service with fast setup times, ability to handle large groups, strong security and priority handling.

An MCPTT service is a push to talk communication service supporting applications for mission critical organizations and mission critical applications for other businesses and organizations (e.g., utilities, railways) with fast setup times, high availability, reliability and priority handling. An MCPTT system is the collection of applications, services, and enabling capabilities required to provide MCPTT for a mission critical organization.

An MCPTT request is the action taken by an MCPTT user to request the permission to transmit voice on a call. An MCPTT private call is a call between a pair of MCPTT users using the MCPTT service with or without MCPTT floor control. An MCPTT group call is a call between more than two MCPTT users using the MCPTT service. MCPTT floor control is an arbitration system in an MCPTT service that determines who has the authority to transmit (talk) at a point in time during an MCPTT call.

General details on MCPTT techniques and specifications can be found in Third Generation Partnership Project (3GPP) 22.179 (MCPTT stage 1), 3GPP TS 23.280 and TS 23.379 (MCPTT), 3GPP 24.379 (MCPTT call control protocol specification), 3GPP 23.280 chapter 5.2.9 (MCPTT migration), and 3GPP 23.781 (study on migration and interconnection for mission critical services).

An MCPTT server is an application server which provides P2P calls (private calls) and group calls (voice-video and data), currently on LTE and over SIP signaling. A client application on a user equipment (UE) makes the authentication and with the client application a user can initiate or receive P2P calls (private calls) and group calls.

A functional alias is a user selectable alias that is tied to the assignment or task of the user. A mission-critical-X (MCX) user can activate one or multiple functional aliases at the same time. The activation of the functional alias(es) will take place after the user has signed in to the MCX service using the MCX user ID. The functional alias can be an alternative identity beside or instead of the MCPTT ID.

Currently, 3GPP 23.379 allows for an MCPTT user to initiate an MCPTT private call towards a partner MCPTT system only with the called party's MCPTT identifier (ID). The usage of functional aliases is defined in 3GPP 23.280 and 23.379, but call initiation using the functional alias is allowed (in 3GPP 23.379) only within one and the same MCPTT system. While table 10.7.2.1.1- 1 of 3GPP 23.379 states for a MCPTT private call request (MCPTT client to MCPTT server) that at least one identity must be present (MCPTT ID or functional alias), according to table 10.7.2.1.2-1 of 3GPP 23.379 ("MCPTT private call request (MCPTT server to MCPTT server)") the MCPTT ID of the called party is stated as a mandatory element. This is necessary because the call initiating MCPTT system cannot be subscribed for the functional alias of the called party (user/client), as that user/client is within another MCPTT system (and never was in the call initiating MCPTT system), such that the primary MCPTT server (of the call initiating MCPTT system) cannot resolve the called functional alias mapping to the MCPTT ID of the called user/client.

This use case might for example be relevant in border crossing scenarios when a dispatcher of one country would like to call the dispatcher of a neighboring country on the other side of the border by her/his functional alias or when a migrated MCPTT user wants to call her/his dispatcher or boss in her/his home MCPTT system.

This use case might for example also be relevant within one country, when an area responsible policemen or police dispatcher would like to call an area responsible firemen or fire dispatcher. Currently, the call can be requested only when the calling party knows the MCPTT ID of the officer who is currently in service (which is not the typical case).

Similar constrains also arise in case within one MCPTT system (with several MCPTT servers) an MCPTT server (from which the call is initiated) is not aware of the functional alias of the called user/client because e.g. the MCPTT server (from which the call is initiated) never subscribed for functional alias status notification about the functional alias of the called user/client. Namely, also in such case the primary MCPTT server (the call initiating MCPTT server) cannot resolve the called functional alias mapping to the MCPTT ID of the called user/client.

As a result, private MCPTT calls can be initiated with a functional alias only within one MCPTT system (and under specific conditions), and private MCPTT call can be initiated towards partner MCPTT systems only with MCPTT ID of the called MCPTT user/client as mandatory element. Hence, the problem arises that in such scenarios the called user/client cannot be addressed by its functional alias but instead the MCPTT ID of the called user/client is necessary which, however, is not always known by the MCPTT server (from which the call is initiated).

Further, both private calls and group calls can be within one or within several MCPTT system(s). Depending on the initiated group calls, the partner MCPTT systems (serving some part of the group call or serving group members) can be different.

In case of several MCPTT systems, the initiating MCPTT server needs to forward call related information towards the partner MCPTT systems (on the interface MCPTT-3 and MCPTT-10).

There is a possibility to initiate MCPTT private and group calls which involve more than one MCPTT system. It can happen that the called party in a private call is under a partner MCPTT system or several group call participants are served by a partner MCPTT system.

For the case of group calls, the MCPTT group configuration data contain a list of partner MCPTT systems, such that group calls can be routed towards the relevant partner MCPTT system to involve the group call participants under that particular MCPTT system.

Namely, currently 3GPP 23.379 table A.4-2 ("Group configuration data (on network)") contains partner MCPTT system related configuration information:

However, at present there is no separate private call configuration data available nor specified, and the MCPTT service configuration data (described in 3GPP 23.379 chapter A.5) does not contain parameters like MC system identity of partner MCPTT system, such that private calls cannot be routed to the partner MCPTT system.

Namely, there is no other configuration parameter accessible for MCPTT private calls about partner MCPTT systems identity. In particular, at present there is no detailed description about how a call initiating MCPTT system defines the identity of the partner MCPTT system to where a private call needs to be routed.

According to 3GPP 23.379 chapter 10.7.2.3.1 it is merely demanded that "if authorized, MCPTT server 1 includes information that it communicates using MCPTT service, offers the same media types or a subset of the media types contained in the initial received request, includes an automatic commencement mode indication if automatic commencement mode was requested by and authorized for the calling user and sends the corresponding MCPTT private call request towards the MCPTT system (via session initiation protocol (SIP) core) of the MCPTT client specified in the original MCPTT private call request (MCPTT client 2) i.e., MCPTT server 2. If location information was included in the private call request, the MCPTT server checks the privacy policy of the MCPTT user to decide if the location information of MCPTT client 1 can be provided to the other user on the call (refer to Annex A.3 "Authorization to provide location information to other MCPTT users on a call when talking")".

Hence, the further problem arises that in such scenarios information for successfully sending MCPTT private call requests towards the MCPTT system corresponding to the called client (e.g. partner MCPTT system related configuration information) are not available for the MCPTT server at which the MCPTT private call is initiated.

Hence, there is a need to provide for mission critical push to talk private call initiation improvements.

Various exemplary embodiments of the present invention aim at addressing at least part of the above issues and/or problems and drawbacks.

Various aspects of exemplary embodiments of the present invention are set out in the appended claims.

According to an example aspect, there is provided a method of a first mission critical push to talk server in a first mission critical push to talk system, the method comprising receiving, from a first mission critical push to talk client, a private call request for a mission critical push to talk private call towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and deciding on a target of forwarding said private call request based on said functional alias information.

According to an example aspect, there is provided a method of a first mission critical push to talk server in a first mission critical push to talk system, the method comprising receiving, from a second mission critical push to talk server, a private call request for a mission critical push to talk private call from a first mission critical push to talk client towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and mapping said functional alias to a mission critical push to talk identifier of said second mission critical push to talk client. According to an example aspect, there is provided an apparatus of a first mission critical push to talk server in a first mission critical push to talk system, the apparatus comprising receiving circuitry configured to receive, from a first mission critical push to talk client, a private call request for a mission critical push to talk private call towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and deciding circuitry configured to decide on a target of forwarding said private call request based on said functional alias information.

According to an example aspect, there is provided an apparatus of a first mission critical push to talk server in a first mission critical push to talk system, the apparatus comprising receiving circuitry configured to receive, from a second mission critical push to talk server, a private call request for a mission critical push to talk private call from a first mission critical push to talk client towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and mapping circuitry configured to map said functional alias to a mission critical push to talk identifier of said second mission critical push to talk client.

According to an example aspect, there is provided an apparatus of a first mission critical push to talk server in a first mission critical push to talk system, the apparatus comprising at least one processor, at least one memory including computer program code, and at least one interface configured for communication with at least another apparatus, the at least one processor, with the at least one memory and the computer program code, being configured to cause the apparatus to perform receiving, from a first mission critical push to talk client, a private call request for a mission critical push to talk private call towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and deciding on a target of forwarding said private call request based on said functional alias information.

According to an example aspect, there is provided an apparatus of a first mission critical push to talk server in a first mission critical push to talk system, the apparatus comprising at least one processor, at least one memory including computer program code, and at least one interface configured for communication with at least another apparatus, the at least one processor, with the at least one memory and the computer program code, being configured to cause the apparatus to perform receiving, from a second mission critical push to talk server, a private call request for a mission critical push to talk private call from a first mission critical push to talk client towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and mapping said functional alias to a mission critical push to talk identifier of said second mission critical push to talk client.

According to an example aspect, there is provided a computer program product comprising computer-executable computer program code which, when the program is run on a computer (e.g. a computer of an apparatus according to any one of the aforementioned apparatus-related exemplary aspects of the present disclosure), is configured to cause the computer to carry out the method according to any one of the aforementioned method- related exemplary aspects of the present disclosure.

Such computer program product may comprise (or be embodied) a (tangible) computer-readable (storage) medium or the like on which the computerexecutable computer program code is stored, and/or the program may be directly loadable into an internal memory of the computer or a processor thereof. Any one of the above aspects enables an efficient initiation of mission critical push to talk private calls without the necessity to request additional information and without the constraints with respect to the cooperating MCPTT servers/sy stems illustrated above even in case only a functional alias of the called user/client is available to thereby solve at least part of the problems and drawbacks identified in relation to the prior art.

By way of exemplary embodiments of the present invention, there is provided mission critical push to talk private call initiation improvements. More specifically, by way of exemplary embodiments of the present invention, there are provided measures and mechanisms for realizing mission critical push to talk private call initiation improvements.

Thus, improvement is achieved by methods, apparatuses and computer program products enabling/realizing mission critical push to talk private call initiation improvements.

Brief description of the drawings

In the following, the present invention will be described in greater detail by way of non-limiting examples with reference to the accompanying drawings, in which

Figure 1 is a block diagram illustrating an apparatus according to exemplary embodiments of the present invention,

Figure 2 is a block diagram illustrating an apparatus according to exemplary embodiments of the present invention,

Figure 3 is a block diagram illustrating an apparatus according to exemplary embodiments of the present invention, Figure 4 is a block diagram illustrating an apparatus according to exemplary embodiments of the present invention,

Figure 5 is a schematic diagram of a procedure according to exemplary embodiments of the present invention,

Figure 6 is a schematic diagram of a procedure according to exemplary embodiments of the present invention,

Figure 7 shows a schematic diagram of signaling sequences according to exemplary embodiments of the present invention, and

Figure 8 is a block diagram alternatively illustrating apparatuses according to exemplary embodiments of the present invention.

Detailed description of drawings and embodiments of the present invention

The present invention is described herein with reference to particular nonlimiting examples and to what are presently considered to be conceivable embodiments of the present invention. A person skilled in the art will appreciate that the invention is by no means limited to these examples, and may be more broadly applied.

It is to be noted that the following description of the present invention and its embodiments mainly refers to specifications being used as non-limiting examples for certain exemplary network configurations and deployments. Namely, the present invention and its embodiments are mainly described in relation to 3GPP specifications being used as non-limiting examples for certain exemplary network configurations and deployments. As such, the description of exemplary embodiments given herein specifically refers to terminology which is directly related thereto. Such terminology is only used in the context of the presented non-limiting examples, and does naturally not limit the invention in any way. Rather, any other communication or communication related system deployment, etc. may also be utilized as long as compliant with the features described herein.

Hereinafter, various embodiments and implementations of the present invention and its aspects or embodiments are described using several variants and/or alternatives. It is generally noted that, according to certain needs and constraints, all of the described variants and/or alternatives may be provided alone or in any conceivable combination (also including combinations of individual features of the various variants and/or alternatives).

According to exemplary embodiments of the present invention, in general terms, there are provided measures and mechanisms for (enabling/realizing) mission critical push to talk private call initiation improvements.

Figure 1 is a block diagram illustrating an apparatus according to exemplary embodiments of the present invention. The apparatus may be a network node 10 such as a (initiating) mission critical push to talk server (in a first mission critical push to talk system) comprising a receiving circuitry 11 and a deciding circuitry 12. The receiving circuitry 11 receives, from a first mission critical push to talk client, a private call request for a mission critical push to talk private call towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client. The deciding circuitry 12 decides on a target of forwarding said private call request based on said functional alias information. Figure 5 is a schematic diagram of a procedure according to exemplary embodiments of the present invention. The apparatus according to Figure 1 may perform the method of Figure 5 but is not limited to this method. The method of Figure 5 may be performed by the apparatus of Figure 1 but is not limited to being performed by this apparatus.

As shown in Figure 5, a procedure (of a first mission critical push to talk server (being a (initiating) mission critical push to talk server) in a first mission critical push to talk system) according to exemplary embodiments of the present invention comprises an operation of receiving (S51), from a first mission critical push to talk client, a private call request for a mission critical push to talk private call towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and an operation of deciding (S52) on a target of forwarding said private call request based on said functional alias information.

Figure 2 is a block diagram illustrating an apparatus according to exemplary embodiments of the present invention. In particular, Figure 2 illustrates a variation of the apparatus shown in Figure 1. The apparatus according to Figure 2 may thus further comprise a forwarding circuitry 21, a matching circuitry 22, a determining circuitry 23, and/or a storing circuitry 24.

In an embodiment at least some of the functionalities of the apparatus shown in Figure 1 (or 2) may be shared between two physically separate devices forming one operational entity. Therefore, the apparatus may be seen to depict the operational entity comprising one or more physically separate devices for executing at least some of the described processes.

According to a variation of the procedure shown in Figure 5, exemplary additional operations are given, which are inherently independent from each other as such. According to such variation, an exemplary method according to exemplary embodiments of the present invention may comprise an operation of forwarding said private call request to said target, said private call request including said functional alias information.

According to exemplary embodiments of the present invention, said a format of said functional alias information is indicative of said target.

According to exemplary embodiments of the present invention, said target is a second mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said second mission critical push to talk system.

Alternatively, according to exemplary embodiments of the present invention, said target is a second mission critical push to talk server in said first mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said second mission critical push to talk server.

According to a variation of the procedure shown in Figure 5, exemplary details of the deciding operation (S52) are given, which are inherently independent from each other as such.

Such exemplary deciding operation (S52) according to exemplary embodiments of the present invention may comprise an operation of matching said functional alias information with structure/filter/mask information corresponding to each of a plurality of target candidates, and an operation of determining a target candidate of said plurality of target candidates for which said functional alias information matches with structure/filter/mask information as said target.

According to a variation of the procedure shown in Figure 5, exemplary additional operations are given, which are inherently independent from each other as such. According to such variation, an exemplary method according to exemplary embodiments of the present invention may comprise an operation of storing said structure/filter/mask information corresponding to each of said plurality of target candidates as mission critical push to talk service configuration data.

According to exemplary embodiments of the present invention, said functional alias is a user selectable alias that is tied to an assignment or a task of a user of said second mission critical push to talk client. Figure 3 is a block diagram illustrating an apparatus according to exemplary embodiments of the present invention. The apparatus may be a network node 10 such as a (terminating) mission critical push to talk server (in a first mission critical push to talk system) comprising a receiving circuitry 31 and a mapping circuitry 32. The receiving circuitry 31 receives, from a second mission critical push to talk server, a private call request for a mission critical push to talk private call from a first mission critical push to talk client towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client. The mapping circuitry 32 maps said functional alias to a mission critical push to talk identifier of said second mission critical push to talk client. Figure 6 is a schematic diagram of a procedure according to exemplary embodiments of the present invention. The apparatus according to Figure 3 may perform the method of Figure 6 but is not limited to this method. The method of Figure 6 may be performed by the apparatus of Figure 3 but is not limited to being performed by this apparatus.

As shown in Figure 6, a procedure (of a first mission critical push to talk server (being a (terminating) mission critical push to talk server) in a first mission critical push to talk system) according to exemplary embodiments of the present invention comprises an operation of receiving (S61), from a second mission critical push to talk server, a private call request for a mission critical push to talk private call from a first mission critical push to talk client towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and an operation of mapping (S62) said functional alias to a mission critical push to talk identifier of said second mission critical push to talk client.

Figure 4 is a block diagram illustrating an apparatus according to exemplary embodiments of the present invention. In particular, Figure 4 illustrates a variation of the apparatus shown in Figure 3. The apparatus according to Figure 4 may thus further comprise a forwarding circuitry 41. In an embodiment at least some of the functionalities of the apparatus shown in Figure 3 (or 4) may be shared between two physically separate devices forming one operational entity. Therefore, the apparatus may be seen to depict the operational entity comprising one or more physically separate devices for executing at least some of the described processes.

According to a variation of the procedure shown in Figure 6, exemplary additional operations are given, which are inherently independent from each other as such. According to such variation, an exemplary method according to exemplary embodiments of the present invention may comprise an operation of forwarding said private call request to said second mission critical push to talk client based on said mission critical push to talk identifier.

According to exemplary embodiments of the present invention, said second mission critical push to talk server is in a second mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said first mission critical push to talk system.

According to further exemplary embodiments of the present invention, in such case, a format of said functional alias information is indicative of said first mission critical push to talk system.

According to exemplary embodiments of the present invention, said second mission critical push to talk server is in said first mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said first mission critical push to talk server.

According to further exemplary embodiments of the present invention, in such case, a format of said functional alias information is indicative of said first mission critical push to talk server. According to still further exemplary embodiments of the present invention, said functional alias is a user selectable alias that is tied to an assignment or a task of a user of said second mission critical push to talk client.

In other words, according to exemplary embodiments of the present invention, the possibility for an MCPTT user to initiate a private MCPTT call with the functional alias of another MCPTT user towards the another MCPTT user under a partner MCPTT system is provided.

Namely, according to these exemplary embodiments of the present invention, the primary MCPTT server (i.e. initiating MCPTT server) is allowed to send an MCPTT private call request to the partner MCPTT server with the functional alias of the called party (i.e. without the MCPTT ID of the called party (client/user)).

In other words, according to exemplary embodiments of the present invention, a private call request can be sent from the primary MCPTT server (i.e. initiating MCPTT server) to the partner MCPTT server with the functional alias of the called party and without the MCPTT ID of the called party (user/client). The partner MCPTT server will do the functional alias to MCPTT ID mapping and the call can be established afterwards.

Further, according to exemplary embodiments of the present invention, the MCPTT configuration data is provided with functional alias formats containing the format of own functional aliases (functional aliases of the own MCPTT system) and formats of functional aliases from partner MCPTT systems. Based on this MCPTT configuration data the primary MCPTT server (i.e. initiating MCPTT server) can define (based on the functional alias of the called party) towards which partner MCPTT system the private call request shall be forwarded.

Heretofore, according to exemplary embodiments of the present invention, MCPTT service configuration data is established with the functional alias formats containing the format of own functional aliases (functional aliases of the own MCPTT system) and formats of functional aliases from partner MCPTT systems.

Namely, according to exemplary embodiments of the present invention, the "List of partner MCPTT system" parameter is relocated from group configuration data to service configuration data as private calls also requires such information. In this way both the private and group calls can access the configuration data containing the partner MCPTT system identities and both call types (private and group calls) can be routed to the appropriate MCPTT system.

Exemplary embodiments of the present invention are applicable both in automatic and manual commencement mode.

Exemplary embodiments of the present invention are useful also for private calls within one MCPTT system (with several MCPTT servers) if the MCPTT server 1 (from which the call is initiated) is not aware of the functional alias client 2 (addressed client), because the MCPTT server 1 never subscribed for functional alias status notification about functional alias client 2. Currently, this call cannot be established as MCPTT server 1 cannot include the called party's MCPTT ID into the private call request. However, according to exemplary embodiments of the present invention, MCPTT server 1 can identify the MCPTT server 2 that is aware of the functional alias client 2, can include the called party's functional alias into the private call request, while the MCPTT server 2 can map the called party's functional alias to the called party's MCPTT ID.

In other words, according to exemplary embodiments of the present invention, a private call request can be sent from the MCPTT server 1 to the MCPTT server 2 with the functional alias of the called party and without the MCPTT ID of the called party (user/client). The MCPTT server 2 will do the functional alias to MCPTT ID mapping and the call can be established afterwards.

In more specific terms, according to exemplary embodiments of the present invention, functional alias structure/filter/mask configuration data is provided (at least at the primary MCPTT server (i.e. initiating MCPTT server)), and/or the MCPTT private call request (MCPTT server to MCPTT server) information elements are modified, and/or the private call setup procedure is modified.

With respect to functional alias structure/filter/mask configuration data provided according to exemplary embodiments of the present invention, it is noted that currently, 3GPP 23.379 table A.4-2 ("Group configuration data (on network)) as cited above contains partner MCPTT system related configuration information.

According to further exemplary embodiments of the present invention, the corresponding part of MCPTT group configuration data (23.379 chapter A.4) is relocated to the MCPTT service configuration data (23.379 chapter A.5), and the MCPTT service configuration data is extended with functional alias structure/filter/mask (e.g. "*.de") information for all partner MCPTT systems. Based on the functional alias structure configured for all the partner MCPTT systems, the primary MCPTT can decide to which partner MCPTT system the MCPTT private call request shall be forwarded, if it was initiated with the functional alias of the called party.

With respect to the MCPTT private call request (MCPTT server to MCPTT server) information elements modified according to exemplary embodiments of the present invention, it is noted that these may be specified as follows in a modified 3GPP 23.379 table 10.7.2.1.2-1 ("MCPTT private call request (MCPTT server to MCPTT server) information elements"), where "0" means optional, and "M" means mandatory, thereby allowing that the communication between the initiating MCPTT server and the terminating MCPTT server may include only the functional alias of the addressed client/user while the private call can nevertheless be established due to the initiating MCPTT server's ability to address the competent terminating MCPTT server based on the functional alias format and the terminating MCPTT server's ability to map the functional alias to the MCPTT ID of the addressed user/client (called party).

That is, according to exemplary embodiments of the present invention, it is newly defined that both "MCPTT ID" ("The MCPTT ID of the called party") and "functional alias" ("The functional alias of the called party") are indicated optional but "at least one identity must be present".

With respect to the private call setup procedure modified according to exemplary embodiments of the present invention, it is noted that this may be specified as follows in a modified 3GPP 23.379 chapter 10.7.2.3.1 ("Private call setup in automatic commencement mode - MCPTT users in multiple MCPTT systems"), also explained with reference to Figure 7 showing a schematic diagram of signaling sequences according to exemplary embodiments of the present invention, thereby allowing that the communication between the initiating MCPTT server and the terminating MCPTT server may include only the functional alias of the addressed client/user while the private call can nevertheless be established due to the initiating MCPTT server's ability to address the competent terminating MCPTT server based on the functional alias format and the terminating MCPTT server's ability to map the functional alias to the MCPTT ID of the addressed user/client (called party).

While Figure 7 and the explanation below illustrates the modified private call setup procedure for the automatic commencement mode, exemplary embodiments of the present invention are applicable to the manual commencement mode and the modification of the private call setup procedure for the manual commencement mode corresponds to that of the modification of the private call setup procedure for the automatic commencement mode.

The procedures illustrated in Figure 7 is for the MCPTT client initiating establishment of a MCPTT private call with the chosen MCPTT user and assumes the following pre-conditions:

1. The calling MCPTT user has selected automatic (manual) commencement mode for the call; or

2. The called MCPTT client is set to automatic (manual) commencement mode. In step 1 of Figure 7, it is assumed that MCPTT users on MCPTT client 1 and MCPTT client 2 are already registered for receiving MCPTT service to their respective MCPTT service provider, as per procedure in subclause 10.2 (of 3GPP 23.379).

In step 2 of Figure 7, the MCPTT user at MCPTT client 1 would like to initiate an MCPTT private call for the chosen MCPTT user. For a private call with floor control, floor control is to be established.

In step 3 of Figure 7, the MCPTT client 1 sends an MCPTT private call request towards the home MCPTT server 1 (via SIP core) using a service identifier as defined in 3GPP TS 23.228 for MCPTT, for establishing private call with the MCPTT client 2 registered at MCPTT service provider 2. The MCPTT private call request contains the MCPTT id or Functional Alias of invited user and an SDP offer containing one or more media types. For a private call with floor control, the MCPTT private call request also contains an element that indicates that MCPTT client 1 is requesting the floor. If the private call request requests the floor it may include location information. The MCPTT client 1 may include a requested commencement mode that indicates that the call is to be established in automatic commencement mode if automatic commencement mode is requested by the initiating user.

That is, according to exemplary embodiments of the present invention, with respect to step 3 it is newly defined that "the MCPTT private call request contains the MCPTT id or Functional Alias of invited user and an SDP offer containing one or more media types" instead of that "the MCPTT private call request contains the MCPTT id of invited user and an SDP offer containing one or more media types".

In step 4 of Figure 7, the MCPTT server 1 checks whether the MCPTT user at MCPTT client 1 is authorized to initiate the private call. If the MCPTT private call request requested automatic commencement mode, then the MCPTT server 1 also checks whether the MCPTT user at MCPTT client 1 is authorized to initiate a call in automatic commencement mode.

In step 5 of Figure 7, the MCPTT server 1 may provide a progress indication to MCPTT client 1 to indicate progress in the call setup process.

NOTE: Step 5 of Figure 7 can occur at any time following step 4 of Figure

7, and prior to step 11 of Figure 7.

In step 6 of Figure 7, if authorized, the MCPTT server 1 includes information that it communicates using MCPTT service, offers the same media types or a subset of the media types contained in the initial received request, includes an automatic commencement mode indication if automatic commencement mode was requested by and authorised for the calling user and sends the corresponding MCPTT private call request towards the MCPTT system (via SIP core) of the MCPTT client specified in the original MCPTT private call request (MCPTT client 2) i.e., MCPTT server 2 (if MCPTT private call request is initiated with called party Functional Alias, then target MCPTT system can be identified from Service configuration data. If the next network node is an MC gateway, then same step shall be repeated and MC gateway shall forward the MCPTT private call request based on the Functional Alias of the called party).

If location information was included in the private call request, the MCPTT server checks the privacy policy of the MCPTT user to decide if the location information of MCPTT client 1 can be provided to the other user on the call (refer to Annex A.3 "Authorisation to provide location information to other MCPTT users on a call when talking").

That is, according to exemplary embodiments of the present invention, with respect to step 6 it is newly defined that "(if MCPTT private call request is initiated with called party Functional Alias, then target MCPTT system can be identified from Service configuration data. If the next network node is an MC gateway, then same step shall be repeated and MC gateway shall forward the MCPTT private call request based on the Functional Alias of the called party)".

In step 7 of Figure 7, the MCPTT server 2 checks whether the MCPTT user at MCPTT client 2 is authorized to receive a private call.

NOTE: If the received MCPTT private call request was received with called party Functional Alias, then MCPTT system should identify the called MCPTT user based on the received Functional Alias before checking whether the MCPTT user is authorized to receive a private call or not.

That is, according to exemplary embodiments of the present invention, with respect to step 7 the note is newly defined that "if the received MCPTT private call request was received with called party Functional Alias, then MCPTT system should identify the called MCPTT user based on the received Functional Alias before checking whether the MCPTT user is authorized to receive a private call or not".

In step 8 of Figure 7, the MCPTT server 2 includes information that it communicates using MCPTT service, offers the same media types or a subset of the media types contained in the initial received request, includes a requested automatic commencement mode indication based on a requested automatic commencement mode by the calling user or based upon the setting of the called MCPTT client and sends the received MCPTT private call request towards the MCPTT client specified by Functional Alias in the received MCPTT private call request (i.e., MCPTT client 2). If the called MCPTT user has registered to the MCPTT service with multiple MCPTT UEs and has designated the MCPTT UE for receiving the private calls, then the incoming MCPTT private call request is delivered only to the designated MCPTT UE.

In step 9 of Figure 7, the receiving MCPTT client 2 notifies the user about the incoming private call. In step 10 of Figure 7, the receiving MCPTT client 2 accepts the private call automatically, and an acknowledgement is sent to the MCPTT server 1 (via SIP core and MCPTT server 2).

In step 11 of Figure 7, upon receiving the MCPTT private call response from MCPTT client 2 accepting the private call request, MCPTT client 1 is informed about successful call establishment.

In step 12 of Figure 7, the MCPTT client 1 and MCPTT client 2 have successfully established media plane for communication and either user can transmit media. For successful call establishment of a private call with implicit floor control request from MCPTT client 1, floor participant at MCPTT client 1 is granted floor by the floor control server at MCPTT service provider 1, giving it permission to transmit. At the same time floor participant at MCPTT client 2 is informed by the floor control server at MCPTT service provider 1 that the floor is taken.

The above-described procedures and functions may be implemented by respective functional elements, processors, or the like, as described below.

In the foregoing exemplary description of the network entity, only the units that are relevant for understanding the principles of the invention have been described using functional blocks. The network entity may comprise further units that are necessary for its respective operation. However, a description of these units is omitted in this specification. The arrangement of the functional blocks of the devices is not construed to limit the invention, and the functions may be performed by one block or further split into sub-blocks.

When in the foregoing description it is stated that the apparatus, i.e. network entity (or some other means) is configured to perform some function, this is to be construed to be equivalent to a description stating that a (i.e. at least one) processor or corresponding circuitry, potentially in cooperation with computer program code stored in the memory of the respective apparatus, is configured to cause the apparatus to perform at least the thus mentioned function. Also, such function is to be construed to be equivalently implementable by specifically configured circuitry or means for performing the respective function (i.e. the expression "unit configured to" is construed to be equivalent to an expression such as "means for").

In Figure 8, an alternative illustration of apparatuses according to exemplary embodiments of the present invention is depicted. As indicated in Figure 8, according to exemplary embodiments of the present invention, the apparatus (network node) 10' (corresponding to the network node 10) comprises a processor 81, a memory 82 and an interface 83, which are connected by a bus 84 or the like. Further, according to exemplary embodiments of the present invention, the apparatus (network node) 30' (corresponding to the network node 30) comprises a processor 85, a memory 86 and an interface 87, which are connected by a bus 88 or the like, and the apparatuses may be connected via link 89, respectively.

The processor 81/85 and/or the interface 83/87 may also include a modem or the like to facilitate communication over a (hardwire or wireless) link, respectively. The interface 83/87 may include a suitable transceiver coupled to one or more antennas or communication means for (hardwire or wireless) communications with the linked or connected device(s), respectively. The interface 83/87 is generally configured to communicate with at least one other apparatus, i.e. the interface thereof.

The memory 82/86 may store respective programs assumed to include program instructions or computer program code that, when executed by the respective processor, enables the respective electronic device or apparatus to operate in accordance with the exemplary embodiments of the present invention.

In general terms, the respective devices/apparatuses (and/or parts thereof) may represent means for performing respective operations and/or exhibiting respective functionalities, and/or the respective devices (and/or parts thereof) may have functions for performing respective operations and/or exhibiting respective functionalities.

When in the subsequent description it is stated that the processor (or some other means) is configured to perform some function, this is to be construed to be equivalent to a description stating that at least one processor, potentially in cooperation with computer program code stored in the memory of the respective apparatus, is configured to cause the apparatus to perform at least the thus mentioned function. Also, such function is to be construed to be equivalently implementable by specifically configured means for performing the respective function (i.e. the expression "processor configured to [cause the apparatus to] perform xxx-ing" is construed to be equivalent to an expression such as "means for xxx-ing").

According to exemplary embodiments of the present invention, an apparatus representing the network node 10 (e.g. (of) a first mission critical push to talk server (initiating MCPTT server) in a first mission critical push to talk system) comprises at least one processor 81, at least one memory 82 including computer program code, and at least one interface 83 configured for communication with at least another apparatus. The processor (i.e. the at least one processor 81, with the at least one memory 82 and the computer program code) is configured to perform receiving, from a first mission critical push to talk client, a private call request for a mission critical push to talk private call towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client (thus the apparatus comprising corresponding means for receiving), and to perform deciding on a target of forwarding said private call request based on said functional alias information (thus the apparatus comprising corresponding means for deciding). According to further exemplary embodiments of the present invention, an apparatus representing the network node 30 (e.g. (of) a first mission critical push to talk server (terminating MCPTT server) in a first mission critical push to talk system) comprises at least one processor 85, at least one memory 86 including computer program code, and at least one interface 87 configured for communication with at least another apparatus. The processor (i.e. the at least one processor 85, with the at least one memory 86 and the computer program code) is configured to perform receiving, from a second mission critical push to talk server, a private call request for a mission critical push to talk private call from a first mission critical push to talk client towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client (thus the apparatus comprising corresponding means for receiving), and to perform mapping said functional alias to a mission critical push to talk identifier of said second mission critical push to talk client (thus the apparatus comprising corresponding means for mapping).

For further details regarding the operability/functionality of the individual apparatuses, reference is made to the above description in connection with any one of Figures 1 to 7, respectively.

For the purpose of the present invention as described herein above, it should be noted that

- method steps likely to be implemented as software code portions and being run using a processor at a network server or network entity (as examples of devices, apparatuses and/or modules thereof, or as examples of entities including apparatuses and/or modules therefore, e.g. MCPTT server), are software code independent and can be specified using any known or future developed programming language as long as the functionality defined by the method steps is preserved; - generally, any method step is suitable to be implemented as software or by hardware without changing the idea of the embodiments and its modification in terms of the functionality implemented;

- method steps and/or devices, units or means likely to be implemented as hardware components at the above-defined apparatuses, or any module(s) thereof, (e.g., devices carrying out the functions of the apparatuses according to the embodiments as described above) are hardware independent and can be implemented using any known or future developed hardware technology or any hybrids of these, such as MOS (Metal Oxide Semiconductor), CMOS (Complementary MOS), BiMOS (Bipolar MOS), BiCMOS (Bipolar CMOS), ECL (Emitter Coupled Logic), TTL (Transistor-Transistor Logic), etc., using for example ASIC (Application Specific IC (Integrated Circuit)) components, FPGA (Field-programmable Gate Arrays) components, CPLD (Complex Programmable Logic Device) components or DSP (Digital Signal Processor) components;

- devices, units or means (e.g. the above-defined network entity or network register, or any one of their respective units/means) can be implemented as individual devices, units or means, but this does not exclude that they are implemented in a distributed fashion throughout the system, as long as the functionality of the device, unit or means is preserved;

- an apparatus like the user equipment and the network entity /network register may be represented by a semiconductor chip, a chipset, or a (hardware) module comprising such chip or chipset; this, however, does not exclude the possibility that a functionality of an apparatus or module, instead of being hardware implemented, be implemented as software in a (software) module such as a computer program or a computer program product comprising executable software code portions for execution/being run on a processor;

- a device may be regarded as an apparatus or as an assembly of more than one apparatus, whether functionally in cooperation with each other or functionally independently of each other but in a same device housing, for example. In general, it is to be noted that respective functional blocks or elements according to above-described aspects can be implemented by any known means, either in hardware and/or software, respectively, if it is only adapted to perform the described functions of the respective parts. The mentioned method steps can be realized in individual functional blocks or by individual devices, or one or more of the method steps can be realized in a single functional block or by a single device.

Generally, any method step is suitable to be implemented as software or by hardware without changing the idea of the present invention. Devices and means can be implemented as individual devices, but this does not exclude that they are implemented in a distributed fashion throughout the system, as long as the functionality of the device is preserved. Such and similar principles are to be considered as known to a skilled person.

Software in the sense of the present description comprises software code as such comprising code means or portions or a computer program or a computer program product for performing the respective functions, as well as software (or a computer program or a computer program product) embodied on a tangible medium such as a computer-readable (storage) medium having stored thereon a respective data structure or code means/portions or embodied in a signal or in a chip, potentially during processing thereof.

The present invention also covers any conceivable combination of method steps and operations described above, and any conceivable combination of nodes, apparatuses, modules or elements described above, as long as the above-described concepts of methodology and structural arrangement are applicable.

In view of the above, there are provided measures for mission critical push to talk private call initiation improvements. Such measures exemplarily comprise, at a first mission critical push to talk server in a first mission critical push to talk system, receiving, from a first mission critical push to talk client, a private call request for a mission critical push to talk private call towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and deciding on a target of forwarding said private call request based on said functional alias information.

Even though the invention is described above with reference to the examples according to the accompanying drawings, it is to be understood that the invention is not restricted thereto. Rather, it is apparent to those skilled in the art that the present invention can be modified in many ways without departing from the scope of the inventive idea as disclosed herein.

List of acronyms and abbreviations

3GPP Third Generation Partnership Project

FA functional alias

ID identifier

MCPTT mission critical push to talk

MCX mission-critical-X

SIP session initiation protocol

UE user equipment

Claims

1. A method of a first mission critical push to talk server in a first mission critical push to talk system, the method comprising receiving, from a first mission critical push to talk client, a private call request for a mission critical push to talk private call towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and deciding on a target of forwarding said private call request based on said functional alias information.

2. The method according to claim 1, further comprising forwarding said private call request to said target, said private call request including said functional alias information.

3. The method according to claim 1 or 2, wherein a format of said functional alias information is indicative of said target.

4. The method according to any of claims 1 to 3, wherein said target is a second mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said second mission critical push to talk system, or wherein said target is a second mission critical push to talk server in said first mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said second mission critical push to talk server.

5. The method according to any of claims 1 to 4, wherein in relation to said deciding, the method further comprises matching said functional alias information with structure/filter/mask information corresponding to each of a plurality of target candidates, and determining a target candidate of said plurality of target candidates for which said functional alias information matches with structure/filter/mask information as said target.

6. The method according to claim 5, further comprising storing said structure/filter/mask information corresponding to each of said plurality of target candidates as mission critical push to talk service configuration data.

7. The method according to any of claims 1 to 6, wherein said functional alias is a user selectable alias that is tied to an assignment or a task of a user of said second mission critical push to talk client.

8. The method according to any of claims 1 to 7, wherein said private call request does not include a mission critical push to talk identifier of said second mission critical push to talk client.

9. A method of a first mission critical push to talk server in a first mission critical push to talk system, the method comprising receiving, from a second mission critical push to talk server, a private call request for a mission critical push to talk private call from a first mission critical push to talk client towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and mapping said functional alias to a mission critical push to talk identifier of said second mission critical push to talk client.

10. The method according to claim 9, further comprising forwarding said private call request to said second mission critical push to talk client based on said mission critical push to talk identifier.

11. The method according to claim 9 or 10, wherein said second mission critical push to talk server is in a second mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said first mission critical push to talk system.

12. The method according to claim 11, wherein a format of said functional alias information is indicative of said first mission critical push to talk system.

13. The method according to claim 9 or 10, wherein said second mission critical push to talk server is in said first mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said first mission critical push to talk server.

14. The method according to claim 13, wherein a format of said functional alias information is indicative of said first mission critical push to talk server.

15. The method according to any of claims 9 to 14, wherein said functional alias is a user selectable alias that is tied to an assignment or a task of a user of said second mission critical push to talk client.

16. The method according to any of claims 9 to 15, wherein said private call request does not include a mission critical push to talk identifier of said second mission critical push to talk client.

17. An apparatus of a first mission critical push to talk server in a first mission critical push to talk system, the apparatus comprising receiving circuitry configured to receive, from a first mission critical push to talk client, a private call request for a mission critical push to talk private call towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and deciding circuitry configured to decide on a target of forwarding said private call request based on said functional alias information.

18. The apparatus according to claim 17, further comprising forwarding circuitry configured to forward said private call request to said target, said private call request including said functional alias information.

19. The apparatus according to claim 17 or 18, wherein a format of said functional alias information is indicative of said target.

20. The apparatus according to any of claims 17 to 19, wherein said target is a second mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said second mission critical push to talk system, or wherein said target is a second mission critical push to talk server in said first mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said second mission critical push to talk server.

21. The apparatus according to any of claims 17 to 20, further comprising matching circuitry configured to match said functional alias information with structure/filter/mask information corresponding to each of a plurality of target candidates, and determining circuitry configured to determine a target candidate of said plurality of target candidates for which said functional alias information matches with structure/filter/mask information as said target.

22. The apparatus according to claim 21, further comprising storing circuitry configured to store said structure/filter/mask information corresponding to each of said plurality of target candidates as mission critical push to talk service configuration data.

23. The apparatus according to any of claims 17 to 22, wherein said functional alias is a user selectable alias that is tied to an assignment or a task of a user of said second mission critical push to talk client.

24. The apparatus according to any of claims 17 to 23, wherein said private call request does not include a mission critical push to talk identifier of said second mission critical push to talk client.

25. An apparatus of a first mission critical push to talk server in a first mission critical push to talk system, the apparatus comprising receiving circuitry configured to receive, from a second mission critical push to talk server, a private call request for a mission critical push to talk private call from a first mission critical push to talk client towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and mapping circuitry configured to map said functional alias to a mission critical push to talk identifier of said second mission critical push to talk client.

26. The apparatus according to claim 25, further comprising forwarding circuitry configured to forward said private call request to said second mission critical push to talk client based on said mission critical push to talk identifier.

27. The apparatus according to claim 25 or 26, wherein said second mission critical push to talk server is in a second mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said first mission critical push to talk system.

28. The apparatus according to claim 27, wherein a format of said functional alias information is indicative of said first mission critical push to talk system.

29. The apparatus according to claim 25 or 26, wherein said second mission critical push to talk server is in said first mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said first mission critical push to talk server.

30. The apparatus according to claim 29, wherein a format of said functional alias information is indicative of said first mission critical push to talk server.

31. The apparatus according to any of claims 25 to 30, wherein said functional alias is a user selectable alias that is tied to an assignment or a task of a user of said second mission critical push to talk client.

32. The apparatus according to any of claims 25 to 31, wherein said private call request does not include a mission critical push to talk identifier of said second mission critical push to talk client.

33. An apparatus of a first mission critical push to talk server in a first mission critical push to talk system, the apparatus comprising at least one processor, at least one memory including computer program code, and at least one interface configured for communication with at least another apparatus, the at least one processor, with the at least one memory and the computer program code, being configured to cause the apparatus to perform : receiving, from a first mission critical push to talk client, a private call request for a mission critical push to talk private call towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and deciding on a target of forwarding said private call request based on said functional alias information.

34. The apparatus according to claim 33, wherein the at least one processor, with the at least one memory and the computer program code, is configured to cause the apparatus to further perform : forwarding said private call request to said target, said private call request including said functional alias information.

35. The apparatus according to claim 33 or 34, wherein a format of said functional alias information is indicative of said target.

36. The apparatus according to any of claims 33 to 35, wherein said target is a second mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said second mission critical push to talk system, or wherein said target is a second mission critical push to talk server in said first mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said second mission critical push to talk server.

37. The apparatus according to any of claims 33 to 36, wherein in relation to said deciding, the at least one processor, with the at least one memory and the computer program code, is configured to cause the apparatus to further perform: matching said functional alias information with structure/filter/mask information corresponding to each of a plurality of target candidates, and determining a target candidate of said plurality of target candidates for which said functional alias information matches with structure/filter/mask information as said target.

38. The apparatus according to claim 37, wherein the at least one processor, with the at least one memory and the computer program code, is configured to cause the apparatus to further perform : storing said structure/filter/mask information corresponding to each of said plurality of target candidates as mission critical push to talk service configuration data.

39. The apparatus according to any of claims 33 to 38, wherein said functional alias is a user selectable alias that is tied to an assignment or a task of a user of said second mission critical push to talk client.

40. The apparatus according to any of claims 33 to 39, wherein said private call request does not include a mission critical push to talk identifier of said second mission critical push to talk client.

41. An apparatus of a first mission critical push to talk server in a first mission critical push to talk system, the apparatus comprising at least one processor, at least one memory including computer program code, and at least one interface configured for communication with at least another apparatus, the at least one processor, with the at least one memory and the computer program code, being configured to cause the apparatus to perform : receiving, from a second mission critical push to talk server, a private call request for a mission critical push to talk private call from a first mission critical push to talk client towards a second mission critical push to talk client, said private call request including functional alias information indicative of a functional alias of said second mission critical push to talk client, and mapping said functional alias to a mission critical push to talk identifier of said second mission critical push to talk client.

42. The apparatus according to claim 41, wherein the at least one processor, with the at least one memory and the computer program code, is configured to cause the apparatus to further perform : forwarding said private call request to said second mission critical push to talk client based on said mission critical push to talk identifier.

43. The apparatus according to claim 41 or 42, wherein said second mission critical push to talk server is in a second mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said first mission critical push to talk system.

44. The apparatus according to claim 43, wherein a format of said functional alias information is indicative of said first mission critical push to talk system.

45. The apparatus according to claim 41 or 42, wherein said second mission critical push to talk server is in said first mission critical push to talk system, and said second mission critical push to talk client is registered with said functional alias to said first mission critical push to talk server. 40

46. The apparatus according to claim 45, wherein a format of said functional alias information is indicative of said first mission critical push to talk server.

47. The apparatus according to any of claims 41 to 46, wherein said functional alias is a user selectable alias that is tied to an assignment or a task of a user of said second mission critical push to talk client.

48. The apparatus according to any of claims 41 to 47, wherein said private call request does not include a mission critical push to talk identifier of said second mission critical push to talk client.

49. A computer program product comprising computer-executable computer program code which, when the program is run on a computer, is configured to cause the computer to carry out the method according to any one of claims 1 to 8 or 9 to 16.

50. The computer program product according to claim 49, wherein the computer program product comprises a computer-readable medium on which the computer-executable computer program code is stored, and/or wherein the program is directly loadable into an internal memory of the computer or a processor thereof.