DE102005007342A1 - Communication system, for voice data messages via push-to-talk-over cellular service, uses server unit to generate further communication service-client units - Google Patents

Abstract

A communication system has a communication service-client-unit set up in order to generate one or more messages which contain at least one criterium. The server unit is set up to generate a list of the further communication service-client-units which fulfill the criterium and to communicate to the communication service-client-units. The communication service-server-unit is set up to prepare the communication service with the communication-client-unit and the further service units, which fulfill the criterium, as subscribers. Independent claims are included for; (1) A method for operating a communication system with communication service-client-unit; (2) A server-unit of a communication system; and (3) A communication service-client-unit of a communication system.

Description

The The invention relates to a communication system, a method of operation a communication system, a server unit, a method for operating a server unit, a communication service client unit and a method of operation a communication service client unit.

Of the Communication service push-to-talk-over-cellular (PoC) makes it possible a user of a mobile subscriber device, voice data to one or more recipients at the same time.

To Typically, a special PoC key is provided on the mobile subscriber unit, according to their operation the user can start to speak voice data.

The Voice data usually becomes already during the Einsprechens by means of a mobile communication network distributed, that is to the one or the desired Receiver transmitted. This process is called streaming.

The transmission takes place in the half-duplex method, that is, during the speech and during the transmission only the transmitter, that is the user who speaks and transmits the voice data, voice data to the recipients can, the receiver but can not simultaneously send voice data to the sender. Especially the transmitter can not be interrupted by the receivers.

clear corresponds to communication via PoC from the user's point of view the conventional CB radio, However, with the extension that the transmitter worldwide to recipients, the by means of the suitable switching technology of at least one mobile radio communication network are reachable, transmit voice data can.

I want one Users of PoC more often He will send voice messages to the same recipients at PoC allows, personal, to define fixed user groups. For example, a user of PoC define a group called "Friends", the appropriate members and their respective address, for example, a SIP URL (Session Initiation Protocol Uniform Resource Locator) in the form of a telephone number or in the form of a SIP address, having.

This Group can then have its own group address in the form of a SIP URL be assigned and in the construction of a PoC session, that is, a communication session using PoC, specifying the group address provided by a user is initiated, all members of the group are from a PoC server machine addressed and invited to the PoC session.

The Prerequisite for that a member of the group can be invited is that Member in the mobile communication network, by means of which the used PoC is provided, logged in, that is "online".

user of PoC active in a PoC session, ie as a transmitter, or passive, this means as receiver, are hereinafter referred to as PoC participants of the PoC session designated.

Group Management (group management) as described in [1] and [2], allows easy handling of groups within PoC. But groups can also be used in the context of other communication services. For example a user can use a corresponding group MMS (Multimedia Message Service) message to all members of his Send family.

in the Case of PoC can be a user using a corresponding Group, for example, a PoC session with all members of his Skat clubs start. For this purpose, in a PoC communication network, i.e. in a communication network providing PoC Group Management server (GM server) provided by means of which the user can create and manage a group. The user is called the administrator of the group.

• – Group identifier (Gruppenidentifikation): Mittels diesem wird die Gruppe eindeutig identifiziert. Er hat beispielsweise die Form sip:myfriends@myname.t-mobile.de
• – Group specific attributes (Gruppen-spezifische Attribute): Diese Attribute spezifizieren genauere Eigenschaften der Gruppe. Dies sind:
• – Group information (Gruppeninformation): Information in Form eines einfachen Textes (beispielsweise "Dies ist meine Familie")
• – Group visibility (Gruppensichtbarkeit): Dies spezifiziert, welche Benutzer die Gruppe (beispielsweise mittels einer Such-Funktion des GM-Servers) finden können. Beispielsweise spezifiziert die Group visibility, dass nur der Administrator der Gruppe die Gruppe finden kann.
• – Group duration (Gruppendauer): Dies spezifiziert, wie lange und/oder wann die Gruppe gültig bzw. verwendbar ist. Beispielsweise kann Group duration spezifizieren, dass die Gruppe der "Fußballstadion-Freunde" eines Benutzers nur samstags zwischen 14-18 Uhr verwendbar ist.
• – Service specific info (Kommunikationsdienstspezifische Informationen): Dies sind für den Kommunikationsdienst, in dessen Rahmen die Gruppe genutzt werden kann, spezifische Informationen. Beispielsweise existiert im Rahmen von PoC eine Unterscheidung zwischen "pre-arranged groups" und "chat groups". So kann, falls die Gruppe im Rahmen von PoC genutzt werden soll, mittels der Service specific info angegeben werden, um was für einen Typ von Gruppe es sich handelt.
• – Group members (Gruppen-Mitglieder): Dies ist eine Liste von Benutzern/Gruppen, die der Gruppe angehören, also von Gruppen-Mitgliedern. Jedes Gruppen-Mitglied, das insbesondere selbst eine Gruppe sein kann, wird mittels einer ID (Identifikation, beispielsweise einer SIP URI) eindeutig spezifiziert. Ferner können für jedes Gruppen-Mitglied folgende Attribute festgelegt werden:
• – Member rights (Mitglied-Rechte): Diese spezifizieren die Rechte des Gruppen-Mitglieds
• – Anonymity (Anonymität): Dies spezifiziert, ob das Gruppen-Mitglied bei einer Kommunikation im Rahmen der Gruppe anonym ist oder nicht
• – Service specific info (Kommunikationsdienstspezifische Informationen): Dies sind Kommunikationsdienst-spezifische Angaben. Im Falle von PoC kann beispielsweise die Funktion eines Moderators einer PoC-Session mittels der Service specific info einem Gruppen-Mitglied zugeordnet werden.

The main components of the specification of a group are according to the prior art:

• - Group identifier: this identifies the group uniquely. For example, it has the form sip: myfriends@myname.t-mobile.de
• - Group specific attributes: These attributes specify more specific properties of the group. These are:
• - Group information: information in the form of a simple text (for example, "This is my family")
• - Group visibility: This specifies which users can find the group (for example, using a search function of the GM server). For example, group visibility specifies that only the administrator of the group can find the group.
• - Group duration: This specifies how long and / or when the group is valid or usable. For example, Group duration may specify that a user's "Football Stadium Friends" group is usable only between 2pm and 6pm on Saturdays.
• - Service specific info: This is specific information for the communication service in which the group can be used. For example, in the context of PoC, there is a distinction between "pre-arranged groups" and "chat groups". Thus, if the group is to be used within PoC, the service specific info can be used to indicate what type of group it is.
• - Group members: This is a list of users / groups that belong to the group, that is, group members. Each group member, which in particular can itself be a group, is uniquely specified by means of an ID (identification, for example a SIP URI). Furthermore, the following attributes can be defined for each group member:
• - Member rights: These specify the rights of the group member
• - Anonymity: This specifies whether or not the group member is anonymous when communicating within the group
• - Service specific info: This is communication service specific information. In the case of PoC, for example, the function of a moderator of a PoC session can be assigned to a group member by means of the service-specific info.

• – Manipulation of groups (Gruppen-Manipulation)
• – Get a list of groups (Gruppenliste anfordern)
• – Create a new group (neue Gruppe erzeugen)
• – Delete a group (Gruppe löschen)
• – Modify group attributes (Gruppen-Attribute verändern)
• – Manipulation of members in a group (Manipulation von Mitgliedern einer Gruppe)
• – Get a list of members (Liste von Gruppen-Mitgliedern anfordern)
• – Add a member to a group (Gruppen-Mitglied zu Gruppe hinzufügen)
• – Delete a member from a group (Gruppen-Mitglied aus einer Gruppe löschen)
• – Modify member attributes (Gruppen-Mitglied-Attribute verändern)

A user with the appropriate right, for example, the administrator of a group, can perform the following group management operations as part of group management of the group (that is, group management) according to the prior art:

• - Manipulation of groups (group manipulation)
• - Get a list of groups
• - Create a new group
• - Delete a group
• - Modify group attributes
• - Manipulation of members in a group (manipulation of members of a group)
• - Get a list of members (request a list of group members)
• Add a member to a group
• - Delete a member from a group (Delete a group member from a group)
• - Modify member attributes (modify group member attributes)

For example, in the context of PoC, a group is made by a user as follows with reference to FIG 1 explained, used.

1 shows a message flow diagram 100 according to the prior art.

In step 106 If the user creates, he is the user of a first PoC client unit 101 , a group (PoC group) to which a second PoC client unit 102 (or the corresponding user) and a third PoC client unit 103 (or the corresponding user) belong in a GM server computer 104 by sending a first message 120 , The PoC group is assigned, for example, the ID (identification) sip: myfriends@abc.de and the user by means of a second message 121 that from the GM server machine 104 in step 107 to the first PoC client unit 101 is sent, communicated.

In step 108 the user selects the PoC group. In step 109 the user starts a PoC session with the PoC group. To do this, it sends using the first PoC client unit 101 a third message 122 to a PoC server computer 105 , The PoC server computer 105 puts in step 110 fixed that in the third message 122 specified ID (sip: myfriends@abc.de) specifies a PoC group. The PoC server computer then sends 105 in step 111 a fourth message 123 to the GM server computer 104 to resolve this PoC group, ie to determine which group members have this PoC group. The GM server computer 104 then send in step 112 by means of a fifth message 124 a list of all group members of the PoC group to the PoC server computer. In this example, the group has the second one PoC client unit 102 and the third PoC client unit 103 on.

By sending a sixth message 125 in step 113 to the second PoC client unit 102 and by sending a seventh message 126 to the third PoC client unit 103 loads the PoC server computer 105 All members of the PoC group to the to be established PoC session. Once the first group member has the invitation in step 114 by means of an eighth message 127 accepts, in this example, the second PoC client unit 102 , gets in step 116 to the initiator of the PoC session, ie to the first PoC client unit 101 a ninth message 128 sent, by means of which it is signaled that the PoC session is now started and voice packets can be sent in the context of the PoC session.

According to the state of technology when defining a group, for example when creating a group Group in a GM server, the members of the group are listed. In particular, the Determining which members the group has is very static. In the case of a group, all the family members of a user as a group member, this is not a serious disadvantage because the family members of a user do not change very often.

in the For example, a taxi operator who creates a group and want to use the group members as all taxis assigned to him (or the corresponding driver) that are currently free, it is very uncomfortable, the group management operation "Add a member to the group" or "Delete a member from the group "at the Perform GM server computer, as soon as a taxi becomes available or is occupied.

Next the considerable effort for the taxi operator and a resulting low ease of use does this to a very high signaling volume for the messages to the GM server, for example on the air interface of a mobile communication system, that for the communication is used.

Further is the information to decide who is currently a member of a Group, possibly to the user (for example in his mobile subscriber unit) not before. The user may need to do this with significant Determine effort.

in the Case of a taxi operator, the taxi operator (or for example his mobile subscriber device) Be notified each time a taxi is vacated or occupied so that the taxi operator is always informed about the current status is. The constant transmission of notification messages also to a very high signaling volume, for example on the air interface of the for the communication used mobile communication system.

Group Management operations using HTTP are described in [2]. HTTP get commands are described in [3].

In [4] is SIP INVITE, in [5] is SIP SUBSCRIBE and in [6] is SIP MESSAGE described. These are methods according to the SIP (Session Initiation Protocol).

In [7] a method for exchanging emails is described in a user can log on to a server and criteria specifying to which other users of sent e-mails should be sent and specify a profile can be used to decide whether sent by other users Emails are sent to him.

pamphlet [8] discloses a network-based system and method for dynamic Administration of user groups. It will periodically dynamic User data compared with group membership criteria to determine the user groups.

Of the Invention is based on the problem, a way to use groups in the context of communication services, in which the above mentioned disadvantages do not occur.

The Problem is solved by a communication system, a method of operation a communication system, a server unit, a method for operating a server unit, a communication service client unit and a method of operation a communication service client unit with the features according to the independent claims solved.

It becomes a communication system with a communication service client unit, another communication service client units, a communication service server unit and a server unit, wherein the communication service client unit is set up to generate one or more messages, which contain at least one criterion from the other communication service client units each fulfilled will or will not be fulfilled and the request for the provision of the communication service and a specification that the other communication service client units, that meet the criterion Participants of the provided communication service should be. The server unit is set up, a list of the other communication service client units, that meet the criterion to generate and transmit to the communication service server unit; and the communication service server unit is set up Communication service with the communication service client unit and the others Communication service client units, that meet the criterion to provide as participants.

Further are a method for operating a communication system, a server unit, a method for operating a server unit, a communication service client unit and a method of operating a communication service client unit according to the above provided communication system described.

clear specifies a user by means of his communication service client unit a criterion according to which when the user through his communication service client unit requesting a communication service, dynamically a group of other users (or other communication service client units) whose group members are created together with the user on the provided communication service, for example one PoC (Push to Talk over Cellular) communication, to participate.

Of the User does not statically put a group at the server unit, For example, a GM (Group Management) server, which he only manages manually Sending messages to the server unit can modify For example, by sending a message that specifies that a specific user should be added to the group, but specified a criterion according to which the server unit automatically (at the start of deployment of the Communication Service) the group determined dynamically.

For example can specify a user in a taxi center as a criterion that all drivers of taxis that are currently free, become a PoC group belong should. The server unit dynamically generates the PoC group, for example by demand at a presence server, for every taxi contains the information if the taxi is currently free. This way the user can always send exactly to the taxis voice messages that are currently free without always updating the PoC group manually to have to and without informing yourself which taxis are currently available, which would require a considerable signaling effort.

On this way increases the invention improves usability and reduces signaling overhead considerably.

In In the example above, the other communication service client units become realized for example by mobile subscriber devices of taxi drivers.

in the Within the scope of the invention the first communication service client unit and the other communication service client units for example, by mobile subscriber devices according to UMTS (Universal Mobile Telecommunication System) standard or the GSM (Global System for Mobile Communication) standard will be realized.

The However, invention is not only applicable when the communication service by means of a mobile communication network is provided, but also if the communication service by means of a landline, for example a PSTN (Public Switched Telephone Network) is provided. In both cases can the communication service is provided via the Internet, For example, the communication service is Internet-based Conference Communication Service and Communication Service Client Units accordingly conference communication terminals. The invention is suitable for one Variety of group-specific communication services.

Clearly, the other communication service client units that are to participate in the communication service, not (only) specified by means of a list, but are vividly "umschrie ben ", for example, filtered out of a list of potential participants according to the criterion and thus set dynamically using a predetermined criterion (or more specifiable criteria).

The Invention allows thus the use of dynamic, defined by means of criteria Groups in the context of communication services.

at the embodiments described below There is still the advantage that these exist on existing, in part already standardized, communication networks based. It have to for the realization of the embodiments no opposite new network elements are added to the existing communication networks, the existing network elements are extended in their functionality.

The embodiments can thus easy and inexpensive will be realized.

In an embodiment the user can specify a value which is the maximum number the other communication service client units connected to the communication service to participate, limited. Thus, the user has control over the Size of the dynamic generated group.

If the group of other communication service client units, that meet the criterion changes while the Communication service is already provided, ie during the Communication service exists, this can be taken into account and, for example additional communication service client units at the time the start of the deployment did not meet the criterion, but now fulfill, become subscribers, for example to the provided communication service (about a conference). Conversely, one of the other communication service client units that meet the criterion no longer fulfilled, be excluded from the provided communication service, for example, be removed from a conference. To realize this, the server unit can check the criteria periodically.

The Server unit and the communication service server unit can by means of the same server computer can be realized.

In an embodiment sends the communication service server unit in response to the second message, a message to the communication service client unit, by means of which communicated to the communication service client unit which of the other communication service client units is up to date fulfill the criterion. The communication service client unit can then confirm whether the communication service actually with the other communication service client units that are up to date fulfill the criterion be provided as participants or not.

clear the invention extends according to the state engineering group management operations. Further will be the requests that the communication service client unit sends to the communication service server unit sends, vividly expanded, for example by the specification, that the communication service with the group members of a dynamically defined Group should be provided as participants.

The Server unit can be configured as a group management server unit and by, for example, a GM (Group Management) server computer, the corresponding opposite The prior art is extended, realized, or by Any other server computer can be realized.

preferred Further developments of the invention will become apparent from the dependent claims. The Further embodiments of the invention, in connection with are described in the communication system, apply mutatis mutandis to the process for operating a communication system, the server unit, the A method of operating a server unit, the communication service client unit and the method of operating a communications service client device.

For example is the request in a first message of the one or more Messages are included and received by the communication service client unit transmitted to the communication service server unit.

In an embodiment is the criterion in a second message of one or more Messages are included and received by the communication service client unit transmitted to the server unit.

In an embodiment is the criterion in the first message of one or more Containing messages (and is forwarded, for example, from the communications service server unit to the server unit).

In an embodiment the server unit is set up to generate the list of other communication service client units to transmit to at least one information server unit a third message, which contains the request for information to check for the other communication service client units the criterion fulfill, required are.

clear requests the server unit at an information server unit, the above for the Critical information has information to it to produce the list according to the criterion.

For example the information server unit is a presence server unit or a location server unit. Accordingly, those are for the criterion relevant, for example, location information or presence information.

Checks the server unit the criteria periodically (to always be able to check which of the other communication service client units meet the criterion currently), For example, she can contact a location server or a Presence server subscribe so that they have status changes of the other communication service client units always informed.

In an embodiment contains the one or more messages further include another list of a part the other communication service client units, and one of the others Communication service client units should only be participants of the provided communication service, if on the other List listed and meets the criterion.

Of the Users of the communication service client unit can thus a Define a list of potential group members from which according to the criterion the participants of the communication service are filtered out.

For example the communication service is a communication service based on SIP (Session Initiation Protocol).

With Help of communication ids (communication identifications) can be made within a SIP session different group communications (or sub-group communications) can be realized using dynamic groups (or sub-groups) become. In particular, for example, "whispering" and "sidebars" can be realized. For example, can a user who participates in a group communication, voice data to send to a dynamically defined subgroup that is only used by the Members of the sub-group can be received.

In an embodiment In the one or more messages, the at least one Criterion according to XML (eXtended Markup Language).

Of the Communication service is, for example, a PoC communication service, a communication service for sending instant messages, an MMS communication service or a conference communication service.

As mentioned above checks the server unit in the course of providing the communication service the list the other communication service client units that meet the criterion fulfill, (for example, periodically) for validity, it updates if applicable and transmitted the updated list to the communication service server unit.

The Communication service server unit can be set up as mentioned above be, according to the updated List to change the participants of the communication service.

In an embodiment the communication service becomes part of another communication service provided by the communications service server unit provided.

Illustratively, dynamically generated subgroups of a group become part of a communica- tion service provided to the group. For example, a PoC communication is established as part of a PoC session, wherein the participants of the PoC communication (or the client units they use) meet the criterion.

embodiments The invention is illustrated in the figures and will be discussed below explained in more detail.

1 shows a message flow diagram according to the prior art.

2 shows a message flow diagram according to an embodiment of the invention.

3 shows a communication system according to an embodiment of the invention.

4 shows a message flow diagram according to an embodiment of the invention.

5 shows a message flow diagram according to an embodiment of the invention.

6 shows a message flow diagram according to an embodiment of the invention.

7 shows a message flow diagram according to an embodiment of the invention.

8th shows a message flow diagram according to an embodiment of the invention.

9 shows a message flow diagram according to an embodiment of the invention.

2 shows a message flow diagram 200 according to an embodiment of the invention.

The message flow 200 takes place between a GM (Group Management) client unit 201 , a ServiceX client device 202 , a ServiceX server unit 203 and a GM (Group Management) server unit 204 instead of. ServiceX stands for any communication service within which groups can be used.

Accordingly, the ServiceX is, for example, a PoC (Push to Talk over Cellular) communication service, a communication service for sending instant messages, an MMS (Multimedia Message Service) communication service or a conference communication service. The ServiceX client unit 202 and the ServiceX server unit 203 are arranged and configured according to the communication service. An architecture for using PoC is explained below.

• – eine Liste von potentiellen Gruppen-Mitgliedern der Gruppe und/oder eine erste Liste von Kriterien;
• – (optional) eine Spezifikation einer maximalen Anzahl von Gruppen-Mitgliedern der Gruppe;
• – (optional) eine Spezifikation, dass das Automatisches-Update-Flag (automatic update flag) gesetzt ist;
• – (optional) sonstige Werte von für den ServiceX spezifischen Parametern.

In step 205 sets the GM client unit 201 at the GM server unit 204 a (PoC) group. To do this, the GM client unit sends 201 a group-creation-request message 216 to the GM server unit 204 , The group-creation-request message 216 includes:

• A list of potential group members of the group and / or a first list of criteria;
• - (optional) a specification of a maximum number of group members of the group;
• (Optional) a specification that the automatic update flag is set;
• - (optional) other values of parameters specific to ServiceX.

The GM server unit 204 then creates a corresponding group and sends in step 206 a reply message 217 to the GM client unit 201 containing a unique identification (ID) of the created group.

• – die Identifikation der Gruppe und/oder eine zweite Liste von Kriterien;
• – (optional) eine weitere Liste von potentiellen Gruppen-Mitgliedern; falls in der group-creation-request-Nachricht 216 bereits eine Liste von potentiellen Gruppen-Mitgliedern angegeben wurde, so kann die weitere Liste von potentiellen Gruppen-Mitgliedern eine Erweiterung der Liste von potentiellen Gruppen-Mitgliedern sein;
• – (optional) die Spezifikation einer maximalen Anzahl von Gruppen-Mitgliedern der Gruppe;
• – (optional) die Spezifikation, dass das Automatisches-Update-Flag gesetzt ist;
• – (optional) eine Anforderungsidentifikation (request ID) für den angeforderten Kommunikationsdienst; in dem Fall, dass ServiceX ein PoC-Kommunikationsdienst ist, ist dies eine PoC-Kommunikations-ID, welche als id_roposal bezeichnet wird;
• – (optional) Werte von sonstigen für den ServiceX spezifischen Parametern.

In step 207 sends the ServiceX client unit 202 a request message 218 with the request to deploy the ServiceX to the ServiceX server unit 203 , The request message 218 includes:

• The identification of the group and / or a second list of criteria;
• - (optional) another list of potential group members; if in the group-creation-request message 216 If a list of potential group members has already been provided, the further list of potential group members may be an extension of the list of potential group members;
• - (optional) the specification of a maximum number of group members of the group;
• - (optional) the specification that the automatic update flag is set;
• - (optional) a request identification (request ID) for the requested communication service; in the case that ServiceX is a PoC communication service, this is a PoC communication ID, which is called id_roposal;
• - (optional) values of other parameters specific to ServiceX.

• – die Identifikation der Gruppe;
• – (optional) die zweite Liste von Kriterien;
• – (optional) die Liste von potentiellen Gruppen-Mitgliedern (darunter ist im Folgenden stets die gegebenenfalls um die weitere Liste von potentiellen Gruppen-Mitgliedern erweiterte Liste von potentiellen Gruppen-Mitgliedern zu verstehen bzw. gegebenenfalls die weitere Liste von potentiellen Gruppen-Mitgliedern selbst, falls in der group-creation-request-Nachricht 216 keine Liste von potentiellen Gruppen-Mitgliedern angegeben wurde);
• – (optional) die Spezifikation einer maximalen Anzahl von Gruppen-Mitgliedern in der Gruppe;
• – (optional) Werte von sonstigen, für den ServiceX spezifischen Parametern.

In step 208 Represents the ServiceX server unit 203 that she can not dissolve the group, ie that she can not designate the current group members. Therefore she sends a request message 219 to the GM server unit 204 with the request that the GM server unit 204 the group dissolves. The request message 219 includes:

• - the identification of the group;
• - (optional) the second list of criteria;
• - (optional) the list of potential group members (which will always be understood below as the list of potential group members, possibly extended to the further list of potential group members, or, where appropriate, the further list of potential group members themselves, if in the group-creation-request message 216 no list of potential group members has been provided);
• - (optional) the specification of a maximum number of group members in the group;
• - (optional) values of other parameters specific to the ServiceX.

If the automatic update flag is set, the ServiceX server unit prompts 203 by means of the request message 219 at the GM server unit 204 a longer-term Group Composite Change Notification. In this case, the ServiceX server unit becomes 203 from the GM server unit 204 informed each time that the composition of the group changes, for example, if a potential group member no longer meets or does not meet the criteria specified by the first list of criteria or the second list of criteria. In particular, in the case of a set auto-update flag, the GM server unit checks 204 Periodically, which potential group members currently meet the criteria.

This subscription, that is, the Group Composite Change Notification request, may alternatively be provided by the ServiceX server unit 203 also be carried out at a later date.

In step 210 determines the GM server unit 204 all users identified (if any) in the list of potential group members who meet the criteria (if any) of the first list of criteria and who meet the criteria (if any) of the second list of criteria. These users form the current list of group members. The way the GM server unit works 204 The current group members (ie, the members of the current list of group members) determined depends on the criteria specified by the first list of criteria and the second list of criteria, respectively. This will be explained below.

In step 211 sends the GM server unit 204 another answer message 220 containing the current list of group members to the ServiceX server unit 203 ,

The steps 212 and 213 are optional. In step 212 transmits the ServiceX server unit 203 an informational message 221 to the ServiceX client unit 202 by which it uses the ServiceX client unit 202 informed about the current list of group members. This can be the information message 221 for example, the number of current group members or the complete current list of group members.

In step 213 sends the ServiceX client unit 202 a confirmation message 222 to the ServiceX server unit 203 with which she in step 207 completed request of ServiceX confirmed. Alternatively, the ServiceX client unit 202 in step 213 withdraw the request for the serviceX and the process is terminated accordingly.

In step 214 will be the one in step 207 performed request for the ServiceX, if not in step 213 was withdrawn using the current list of group members from the ServiceX server unit 203 served. Depending on what type of communication service the ServiceX is, this is done by the ServiceX server unit 203 appropriate actions performed, such as an invitation of the group members to a group communication.

• – (optional) die momentane Liste von Gruppen-Mitgliedern;
• – eine Antwort-Identifikation (response ID); in dem Fall, dass der ServiceX ein PoC-Kommunikationsdienst ist, ist dies eine PoC-Kommunikations-ID, welche als PK_id bezeichnet wird;
• – (optional) Werte von sonstigen, für den ServiceX spezifischen Parametern.

In step 215 sends the ServiceX server unit 203 to confirm the in step 207 request the ServiceX request a request acknowledgment message 223 to the ServiceX client unit 202 , The request confirmation message 223 includes:

• - (optional) the current list of group members;
• A response ID (response ID); in the case that the service X is a PoC communication service, this is a PoC communication ID, which is referred to as PK_id;
• - (optional) values of other parameters specific to the ServiceX.

Has the ServiceX server unit 203 at the GM server unit 204 a Group Composite Change Notification is requested so the ServiceX server unit becomes 203 when the current list of group members changes over the changed current list of group members. Such is the ServiceX server unit 203 always known the current composition of the current list of group members. Depending on what type of communication service the ServiceX is concerned with changing the current list of group members (and the corresponding notification of the ServiceX server unit 203 ) associated with certain actions, such as an invitation to the current list of group members newly added group member to a group communication.

In another embodiment, the steps become 205 to 211 performed as described above. step 212 However, it is necessary and the information message 221 contains the current list of group members as well as a temporary group identification. In step 213 sends the ServiceX client unit 302 not a confirmation message 222 to the ServiceX server unit 203 but a re-request of the ServiceX to the ServiceX server unit 303 indicating the temporary group identification. The further procedure is analogous to above from step 214 ,

In one embodiment, the GM server unit is 204 not configured as a separate functional unit, but the functionality of the GM server unit described above 204 is provided by the ServiceX server unit 203 accepted. In particular, the interaction between the GM server unit is eliminated 204 and the ServiceX server unit 203 in the steps 219 and 220 and the notifications to the ServiceX server unit 203 as part of a Group Composite Change Notification.

3 shows a communication system 300 according to an embodiment of the invention.

A first PoC client unit 301 , a second PoC client unit 302 and a third PoC client unit 303 are each using an interface 304 each with a PoC subscriber server computer (PoC server computer Participant Function) 305 coupled. The PoC subscriber server computers 305 are with a PoC control server computer (PoC server computer controlling function) 306 coupled.

The PoC control server computer 306 is with a location server computer 307 , a GM (Group Management) server 308 and a presence server computer 309 coupled. The GM server computer 308 , is also with the location server computer 307 and the presence server computer 309 coupled.

The location server computer 307 provides location information. For example, the GM server computer 308 at the location server computer 307 the location of the second PoC client unit 302 ask.

The presence server computer calculator 309 provides presence information. For example, the GM server computer 308 at the presence server computer 309 ask if the second PoC client unit 302 is currently available and not, for example, is switched off or for any other reason no communication link can be established to her.

The interfaces 304 For example, by means of the RAN (Radio Access Network), the Core Network (CN) and the Internet Protocol Based Multimedia Subsystem (IMS) of a Universal Mobile Telecommunication System (UMTS) communication system or a Global System for Mobile Communication (GSM), Communication system provided.

The interfaces 304 however, they may also be provided, for example, by means of a PSTN (Public Switched Telephone Network) communication network.

The PoC client units 301 . 302 . 303 are each in a mobile communication terminal, according to the respective interface 304 For example, is set up for communication according to the UMTS standard, the GSM standard, the GPRS (General Packet Radio Service) standard or another mobile communication standard.

4 shows a message flow diagram 400 according to an embodiment of the invention.

The message flow shown is between a PoC client unit 401 , a PoC control server 402 , a GM server computer 403 , a location server machine 404 , a presence server computer 405 as well as other PoC client units 406 instead, as related to 3 are arranged and configured, wherein the second PoC client unit 302 and the third PoC client unit 303 the further PoC client unit 406 correspond.

• – allen seinen Freunden,
• – die sich momentan in der gleichen Stadt aufhalten wie er (in diesem Beispiel ist dies ein erstes Kriterium; criteria_1)
• – und die momentan nicht arbeiten (in diesem Beispiel ist dies ein zweites Kriterium; criteria_2)

eine PoC-Session starten möchte.In the embodiment explained below, it is assumed that the user of the PoC client unit 401 With

• - to all his friends,
• - who are currently in the same city as he is (in this example, this is a first criterion; criteria_1)
• - and that are currently not working (in this example, this is a second criterion; criteria_2)

would like to start a PoC session.

To do this, the user sets the PoC client unit 401 by sending a group_generation_request message 423 in step 407 a PoC group in the GM server computer 403 at. To define the PoC group, the user submits one in the group_generation_request message 423 contained listing (member_list) of twenty different users (the user's friends, these are the potential group members) and one in the group generation_request message 423 Specified first criterion (criteria_1) that the friends should be in the city of Hamburg at the time of using the PoC group.

The For example, sending the group_generation_request message may can be realized by means of an HTTP get command, as shown in the table 1 is configured.

Tabelle 1

Table 1

HTTP get commands are described in [3] (Group Management Operations using HTTP are described in [2]).

In Table 1 and in the other tables are the entries that according to the embodiments across from the conventional one News in addition are provided, shown in bold.

In step 408 sends the GM server computer 403 in response a group_generation_response message 424 which contains a unique group identification of the PoC group, in this case the identification sip: myfriends@abc.de, to the PoC client unit 401 ,

In step 409 the user selects the PoC client unit 401 the PoC group and sets the second criterion (criteria_2) (the first criterion and the second criterion can each also consist of several criteria), in order with the potential group members of the PoC group, which the first criterion and the second Meet criterion using the PoC client unit 401 to start a PoC session. The first criterion and the second criterion dynamically describe the PoC group because, over time, the potential group members, ie the users, in the group_generation_request message may change 423 list of users listed, meet the first criterion and the second criterion.

The user of the PoC client unit 401 would like the current composition of the PoC group to be taken into account during the PoC session to be started. The PoC group currently consists of the potential group members who meet the first criterion and the second criterion. In particular, in the course of the PoC session, potential group members who have not previously participated in the PoC session should be invited to the PoC session if they meet the first criterion and the second criterion (as opposed to before). To accomplish this, the user sets the PoC client unit 401 the automatic update flag (automatic_update_flag).

In step 410 the user sends an INVITE message to start the PoC session 425 to the PoC control server computer 402 , The INVITE message 425 is designed according to a SIP INVITE. SIP INVITE is described in [4]. The INVITE message 425 contains a specification of the second criterion (criteria_2) as well as the specification that the automatic update flag is set. This takes place, for example, by means of a content type newly defined in comparison with the prior art. The INVITE message 425 is designed, for example, according to Table 2.

Tabelle 2

Table 2

In step 411 represents the PoC control server 402 after receiving the INVITE message 425 It is clear that he can not dissolve the PoC group, ie that he can not determine from which group members the PoC group is currently composed.

Accordingly, the PoC control server computer asks 402 by transmitting a first SUBSCRIBE message 426 in step 412 at the GM server computer 403 to identify the current (current) group members, ie the group members that make up the PoC group currently. To the GM server computer 403 to allow the current group members to be identified contains the first SUBSCRIBE message 426 the second criterion. The first SUBSCRIBE message 426 is configured in this embodiment according to a SIP SUBSCRIBE, for example according to Table 3 (SIP SUBSCRIBE is described in [5].).

Tabelle 3

Table 3

The second criterion is as mentioned in that the group members should not work at the moment.

As the GM server computer 403 In order to determine the current group members, both the location status of the potential group members (or the PoC client units used by the potential group members) is required, the GM server computer sends 403 in step 413 a second SUBSCRIBE message 427 (according to SIP SUSCRIBE) to the location server computer 404 at the location server computer 404 to subscribe and to be informed about the respective location status of the potential group members.

Furthermore, the GM server computer is required 403 for determining the current group members, whether the potential group members are currently working. This information is for each potential group member in one for that group member of the presence server computers 405 managed presence information (presence status). Accordingly, the GM server computer sends 403 a third SUBSCRIBE message 428 in step 414 to the presence server computer 405 , The second SUBSCRIBE message 427 and the third SUBSCRIBE message 428 will be transmitted to each potential group member. In 4 this is exemplary for the first group member with the identification sip: freund_01@web.de, which in the first SUBSCRIBE message 427 and the second SUBSCRIBE message 428 is shown.

As mentioned, the first criterion is that the friends, ie the potential group members, should stay in the city of Hamburg. Alternatively, the first criterion may also be a location criterion that depends on the location of the user (or the PoC client unit 401 ) depends. The first criterion could be, for example, that only potential group members (or their PoC client units) are within 5 km of the user or PoC client unit location 401 ) stop. In this case, the GM server computer is required 403 for determining the current group members also the location information of the user of the PoC client unit 401 and accordingly sends the first SUBSCRIBE message 427 not just for each potential group member to the location server machine 404 but also for the user of the PoC client unit 401 , However, it is assumed that the first criterion is that the group members should be in the city of Hamburg.

The first SUBSCRIBE message 427 as mentioned, each for each potential group member to the location server computer 404 is transmitted from the location server computer 404 in step 415 each with a first NOTIFY message 429 which contains the location status of the respective group member.

Analog will be in step 416 the second SUBSCRIBE message 428 , if applicable, for each group member to the presence server computer 405 is sent, each from the presence server computer 405 by sending a second NOTIFY message 430 to the GM server computer 403 answered.

The second NOTIFY message 430 contains for each potential group member the information as to whether the respective potential group member is currently working.

Using the in step 415 and step 416 the GM server computer determines in step 417 the current group members by checking for each potential group member whether the potential group member meets the first criterion and the second criterion. In step 418 transmitted by the GM server computer 403 by means of a third NOTIFY message 431 the list of current group members (current_member_list) to the PoC control server 402 , The third NOTIFY message 431 is configured in this example according to a SIP NOTIFY and according to Table 4.

Tabelle 4

Table 4

After receiving the third NOTIFY message 431 is the PoC control server 402 informs which users are current group members. Optional are now the steps 419 and 420 carried out. In step 419 the PoC control server sends the list of current group members (current_member_list), in another embodiment, only the number of the current group members, by means of a MESSAGE message 432 to the PoC client unit 401 , The MESSAGE message 432 is configured as SIP MESSAGE. SIP MESSAGE is described in [6].

In step 420 replies the PoC client unit 401 by means of a second MESSAGE message 433 , which is also configured in accordance with SIP MESSAGE and specifies in this example that the PoC session with the current group members should actually be started.

In step 421 sends the PoC control server 402 a second INVITE message 434 to all current group members, in this example to all other PoC client units 406 , The second INVITE message 434 is configured as SIP INVITE. step 421 is clearly an invitation to all other PoC client units 406 to the PoC session to be established. This is done in a conventional way. In response, the other PoC client units send 406 each a first 200 OK message 435 (according to SIP 200 OK) to the PoC control server computer 401 ,

By sending the first 200 OK message 435 accepts one of the other PoC client units 406 (or the corresponding user) the invitation to the to be established PoC session. After the PoC control server 402 the first 200 OK message 435 received (ie as soon as one of the current group members has accepted the invitation to the PoC session) sends the PoC control server a second 200 OK message 436 to the PoC client unit 401 , which signals that one of the current group members has accepted the invitation to the PoC session.

Now the PoC session is running with all friends of the user of the PoC client unit 401 that meet the first criterion and the second criterion (and have accepted the invitation to the PoC session).

5 shows a message flow diagram 500 according to an embodiment of the invention.

The illustrated message flow is analogous to that with reference to FIG 4 described embodiment between a PoC client unit 501, a PoC control server computer 502 , a GM server computer 503, a location server computer 504 , a presence server computer 505 and other PoC client units 506 instead of.

In this embodiment, it is assumed that the user of the PoC client unit 501 with all users of PoC who are currently in the same university as he and who are currently not working, would like to start a PoC session. The term "current group members", etc. will be used hereinafter in analogy to that with reference to 4 illustrated embodiment used.

In step 507 transmits the PoC client unit 501 a group_generation_request message 524 to the GM server computer 503 to request that a PoC group be generated. The group_generation_request message 524 contains the specification of a first criterion (criteria_1), which states that at the time of the PoC session, ie at the time of using the PoC group in a PoC session, the group members are in the same university as the user of the PoC client unit 501 to stop. The group_generation_request message 524 also contains a specification of a second criterion (criteria_2) stating that the current group members (the PoC group) should not work. The group_generation_request message 524 For example, as shown in Table 5, the user sets by submitting the group_generation_request message 524 the PoC group dynamically defined by the first criterion and the second criterion.

Tabelle 5

Table 5

Now it is necessary that the GM server computer 503 determines all PoC users who meet the first criterion and the second criterion.

In one embodiment, which is not in 5 is shown, the GM server computer goes 530 as follows. Unlike the related to 4 explained embodiment was the GM server computer 503 from the PoC client unit 501 no list of potential group members transmitted. Therefore, the GM server computer determines 503 a list of potential group members, vividly a general list of members as a basis. For this purpose, the GM server computer at one or more network units requests a list of known or suitable PoC client units. These network units are for example an HLR (Home Location Register (the same operator)), which is also the communication network for communication between the PoC client unit 501 and the GM server computer 503 provides a "meta" HLR, ie an HLR that has stored over the information of HLRs from different operators, or different HLRs from different operators.

The requested list of potential group members uses the GM server computer 503 vividly as a basis and sends analogous to those with reference to 4 explained steps 413 and 414 SUBSCRIBE messages for each potential group member to the location server computer 504 or to the Presence server computer 505 and thus determines the location information and presence information of the potential group members required to determine the current list of group members. Subsequently, the GM server computer determines 503 the current list of group members (current_member_list). As the list of potential group members, the GM server computer 503 determined in this embodiment, which can typically be very large, a very high signaling effort is required, in particular for creating the list of potential group members. Therefore, the following embodiment is preferred, which also in 5 is illustrated.

In step 508 sends the GM server computer 503 a first SUBSCRIBE message 525 at the location server computer 504 , The first SUBSCRIBE message 525 will not only go to the location server machine 504 sent to all suitable location servers, ie to location servers, which manage location information of PoC client units.

By way of example, the further procedure is based on the location server computer 504 explained. The in steps 508 submitted first SUBSCRIBE message 525 has a specification of the first criterion (which is illustratively location-specific). The first SUBSCRIBE message 525 is designed, for example, according to Table 6.

Tabelle 6

Table 6

In step 509 the location server answers 504 Subscribe to the GM server 503 ie the first SUBSCRIBE message 525 , by transmitting a first NOTIFY message 526 to the GM server computer 503 , In this way, the location server computer signals 504 the GM server computer 503 a list of (PoC) users (or a list of PoC client units used by the users) that meet the first criterion (matched_users_list_1). The first NOTIFY message 526 is designed, for example, according to Table 7.

Tabelle 7

Table 7

Analogous to the steps 508 and 509 become the steps 510 and 511 carried out. That is, the GM server computer 503 transmitted in step 510 a second SUBSCRIBE message 527 with a specification of the second criterion to the presence server computer 505 (By way of example, analogously to the above, in each case a second SUBSCRIBE message is transmitted to all suitable presence server computers). In step 511 the presence server computer answers 505 by sending a second NOTIFY message 528 at the GM server computer 503 containing a list of (PoC) users (or a list of PoC client units used by users) that meet the second criterion (matched_users_list_2).

In step 512 determines the GM server computer 503 The current list of group members (current_member_list), taking the intersection of the list of users (or the PoC client units used by the users) that meet the first criterion and the list of users (or users) PoC client units used by users) that meet the second criterion.

In another embodiment, the second SUBSCRIBE message 527 sent to such presence server computers only, the presence information about users (or the PoC client units used by the users) contained in the NOTIFY message 526 listed, manage. The GM server computer asks clearly 503 only for the users who meet the first criterion. Accordingly receives the GM server computer 503 in step 511 only for the users who meet the first criterion, presence information. Using this presence information and the step in step 509 obtained information is determined by the GM server computer 503 in step 512 the current list of group members.

The further course is independent of how the current list of group members was determined, in particular the following procedure is also carried out if, as described above, the GM server computer 503 First, a list of potential group members is determined, for example, by requesting information from one or more HLRs.

In step 513 the GM server computer answers 503 that from the PoC client unit 501 in step 507 Request made by submitting a group_generation_response message 529 to the PoC client unit 501 , The group_generation_response message 529 contains a unique group identification of the created PoC group, in this case sip: myfriends@abc.de, and the current list of group members (or alternatively only the number of users that is part of the current list of group members ).

At a later date, in step 514 , the user selects the PoC client unit 501 the PoC group to contact the current group members of the PoC group via the first PoC client unit 501 to start a PoC session. Furthermore, the current composition of the PoC group should also be taken into account during the PoC session, ie the current group members (even if they change during the PoC session) should always be part of the PoC sessions (if this one Accept invitation).

For example, in the course of the PoC session, group members should be invited as soon as they have meet the first criterion and the second criterion. To accomplish this, the user sets the automatic update flag (automatic_update_flag).

In step 515 the user sends using the first PoC client unit 501 a first INVITE message 530 to start the PoC session. The first INVITE message 530 is configured in this example according to a SIP INVITE addressed to the unique group identification. In the first INVITE message 530 is specified that the automatic update flag is set, for example, by specifying this specification as a SIP header in the first INVITE message 530 is included.

Accordingly, the first INVITE message 530 designed according to Table 8.

Tabelle 8

Table 8

In step 516 represents the PoC control server 502 after receiving the first INVITE message 530 that he can not resolve the PoC group specified by means of the group identification. In step 531 Therefore, he asks by means of a third SUBSCRIBE message 531 at the GM server computer 503 that this determines the current group members. The third SUBSCRIBE message 531 is designed according to a SIP SUBSCRIBE and Table 9.

Tabelle 9

Table 9

In step 518 the GM server computer answers 503 to the third SUBSCRIBE message 531 by making the list of current group members by means of a third NOTIFY message 518 to the PoC control server computer 502 transmitted. The third NOTIFY message 532 is designed according to Table 10.

Tabelle 10

Table 10

After receiving the third NOTIFY message 532 is the PoC control server 502 informs which users are current group members. Optional are now the steps 519 and 520 carried out. In step 519 sends the PoC control server 502 the list of current group members (current_member_list), in another embodiment, only the number of the current group members, by means of an UPDATE message 533 to the PoC client unit 501 , The UPDATE message 533 is configured as SIP UPDATE (or alternatively as SIP INFO).

In step 520 replies the PoC client unit 501 by means of a second UPDATE message 534 , which is also configured in accordance with SIP UPDATE and specifies in this example that the PoC session with the current group members should actually be started. The PoC client unit 501 At this point in time, you can stop the flow by using the second UPDATE message instead 534 a CANCEL message (according to SIP CANCEL, see [4]) to the PoC control server computer 502 transmitted.

In step 521 sends the PoC control server 502 a second INVITE message 535 to all current group members, in this example to all other PoC client units 506 , The second INVITE message 535 is configured as SIP INVITE. step 521 is clearly an invitation to all other PoC client units 506 to the PoC session to be established. This is done in a conventional way. In response, the other PoC client units send 506 each a first 200 OK message 536 (according to SIP 200 OK) to the PoC control server computer 401 ,

By sending the first 200 OK message 536 accepts one of the other PoC client units 506 (or the corresponding user) the invitation to the to be established PoC session. After the PoC control server 502 the first 200 OK message 536 received (ie as soon as one of the current group members has accepted the invitation to the PoC session) sends the PoC control server a second 200 OK message 537 to the PoC client unit 401 , which signals that one of the current group members has accepted the invitation to the PoC session.

Now is running? PoC session with all PoC users, the first criterion and meet the second criterion (and have accepted the invitation to the PoC session).

After expiration of in 4 and 5 As has been explained, message flows shown are a PoC session between the first PoC client unit 401 . 501 and the PoC client units that make up the current list of group members. The following is with reference to 6 and 7 explains how to proceed according to an embodiment of the invention when the composition of the current list of group members changes.

6 shows a message flow diagram 600 according to an embodiment of the invention.

Corresponding 4 and 5 the illustrated message flow finds between a PoC client unit 601 , a PoC control server 602 , a GM server computer 603 , a location server machine 604 and other PoC client units 605 carried out the corresponding in 4 and 5 correspond to network elements shown. There is also a newly added PoC client unit 606 involved in the presented message flow.

As mentioned, it is assumed that a PoC session with the current group members is established as a subscriber, it is also assumed that the automatic update flag is set and the PoC control server computer 602 has been informed, for example by means of the first INVITE message 530 that in step 515 was transmitted.

It is assumed that the newly added PoC client unit 606 (or the user of the newly added PoC client unit) has not yet participated in the PoC session. For example, the current list of group members is determined according to the criterion that the current group members are to be in Hamburg (along with their PoC client units), the user of the newly added PoC client unit 606 , this is the user named Freund_17, but has not been in Hamburg until now, but now comes back to Hamburg during the already established PoC session.

It is further assumed that the GM server computer 603 at the location server 604 has requested to obtain location information about the user friend_17, for example, has been in step 413 for the user friend_17, a corresponding second SUBSCRIBE message 427 to the location server 404 because user friend_17 appears on the list of potential group members. Any further criteria according to which the current list of group members is determined, for example as above a criterion on the availability of the group members, is fulfilled by the user friend_17, for example he has set a corresponding presence status.

In step 607 becomes the GM server computer 603 as requested by a first NOTIFY message 614 informed that the user friend_17 with the newly added PoC client unit 606 is back in Hamburg, ie the GM server computer 603 is informed about the location status of the user friend_17 (location_status_17).

After receiving the first NOTIFY message 314 determines the GM server computer 603 in step 608 Recurring the current list of group members again vividly filters the criteria, and now finds that the user friend_17 meets all the specified criteria.

As described above, the PoC control server also has 602 a SUBSCRIBE message to the GM server computer 603 sent (for example, the first SUBSCRIBE message 426 in step 412 ) and requesting that he be informed about the current composition of the PoC group.

Accordingly, the GM server computer sends 603 in step 609 a second NOTIFY message 615 to the PoC control server computer 602 , by means of which the PoC control server computer 602 informed that a new current group member (new_member_17) has been added.

The following steps 610 and 611 are optional.

In step 610 sends the PoC control server 602 a first MESSAGE message 616 (according to SIP MESSAGE), to the PoC client unit 601 and thus informs the PoC client unit 601 about the newly added current group member.

The PoC client unit 601 sends in response in step 611 a second MESSAGE message 617 , by means of which the PoC client unit 601 confirms that the user friend_17 should be added, ie invited, to the current PoC session. In step 612 loads the PoC control server 602 the newly added PoC client unit 606 to the PoC session. This is done by sending an INVITE message 618 , The newly added PoC client unit 606 answers the INVITE message 618 in step 613 by means of a 200 OK message 619 , The steps 612 and 613 be in a conventional manner according to a SIP INVITE and a SIP 200 OK done. Subsequently, the user friend_17 participates in the PoC session.

7 shows a message flow diagram 700 according to an embodiment of the invention.

The illustrated message flow takes place as in 6 between a PoC client unit 701 , a PoC control server 702 , a GM server computer 703 , a location server machine 704 and other PoC client units 705 instead of. The assumptions apply as at the beginning of the 6 explained process, only this time is not in the course of PoC session a new user (or a new PoC client unit) added to the PoC session, but a leaving PoC client unit 706 which of the user with the Name friend_05 is used, leaves the PoC session.

First, it is assumed that the user friend_05 by means of the leaving PoC client unit 706 participates in the existing PoC session. In particular, the user friend_05 so far fulfills the criteria according to which the current group members are determined. Now it is assumed that the friend_05 violated one of the criteria. For example, one criterion is that the current group members should reside in the city of Hamburg, and the user friend_05 leaves with the leaving PoC client unit 706 the city of Hamburg.

Analogous to step 607 sends the location server computer 704 then a NOTIFY message 714 in step 707 to the GM server computer 703 , by means of which the GM server computer is informed about the new location status of the user friend_05.

Analogous to step 608 determines the GM server computer 703 in step 708 again the current composition of the PoC group. This is the GM server computer 703 determines that the user friend_05 does not meet the criteria that the current group members should meet.

Accordingly and analogous to step 609 he informs in step 709 the PoC control server computer 702 by means of a second NOTIFY message 715 that user friend_05 is no longer a current group member.

The steps 710 and 711 are optional. In step 710 sends the PoC control server 702 a first MESSAGE message 716 (according to SIP MESSAGE) is configured to the PoC client unit 701 and thus signals the PoC client unit 701 that user friend_05 is no longer a current group member (remove_member_05). In step 711 confirms the PoC client unit 701 by means of a second MESSAGE message 717 (according to SIP MESSAGE) that the user friend_05 should be removed from the existing PoC session.

In step 712 removes the PoC control server 702 the leaving PoC client unit 706 from the existing PoC session by the PoC control server 702 a BYE message 718 to the leaving PoC client unit 706 sends.

This confirms the leaving PoC client unit 706 in step 713 by means of a 200 OK message 719 , The steps 712 and 713 are performed, for example, in a conventional manner.

Then it is the user friend_05 is no longer part of the existing PoC session.

The following is with reference to 8th and 9 an embodiment described for another application in which a different signaling is performed as in the embodiments described above.

8th shows a message flow diagram 800 according to an embodiment of the invention.

Analogously to the embodiments described above, the message flow shown is located between a PoC client unit 801 , a PoC control server 802 , a GM server computer 803 , a location server machine 804 , a presence server computer 805 as well as other PoC client units 806 instead of.

There are two functional units of the PoC control server computer 802 considered: a session controller 807 as well as a media mixer 808 , The session controller 807 is for the signaling tasks of the PoC control server computer 802 responsible, ie he leads from the PoC control server computer 802 Signaling to be performed, for example, signaling to invite a PoC client unit to a PoC session. These signaling are performed according to the SIP (Session Initiation Protocol). The media mixer (media mixer) 808 regulates the distribution of communication data as part of a PoC session to all participating in the PoC session PoC client units.

In this embodiment, it is assumed that the PoC client unit 801 the PoC client unit is a taxi center of a Berlin taxi company. All taxi drivers (each equipped with one of the other PoC client units) should become a PoC group called "taxis" 906 ) belong. Each time the taxi center receives an order for passenger transport, should one PoC communication is started within a running PoC session, whereby all taxi drivers (or the PoC client units they use) should take part in the PoC communication, which are within x kilometers of the passengers to be transported and have their presence status set to "taxi-free" signaling that they are not transporting a passenger.

A PoC communication within the PoC session is performed as explained below an identification is uniquely identified and between the participants the PoC communication (which are a subgroup of the participants of the PoC session) are (under the PoC session and as part of the PoC communication) voice data exchanged. For example, in the course of a PoC session, the while a whole day (between all the taxi drivers and the taxi center), several PoC communications built in the context of several content related Voice messages (between the participants of the respective PoC communication) transmitted become.

The Generate multiple PoC communications (one for each incoming order) within a PoC session has against the Creating multiple PoC sessions (one per job) has the advantage of that requires significantly less signaling overhead is.

First, in a conventional manner, a PoC session between the PoC client unit 801 and the other PoC client units 806 which, as mentioned, are the PoC client units of all registered taxis, ie all taxis currently in service (regardless of whether the taxis are free or busy) (this step is not shown). This may be done in a conventional manner, for example as with reference to FIG 1 explained. For the rest, it is irrelevant whether it is a so-called one-to-many-to-one topology (ie the PoC client unit 801 receives communication data from all other PoC client units as part of the PoC session 806 but the other PoC client units 806 do not receive each other communication data, ie receive no communication data from the other PoC client units of other PoC client units 806 ) or is a one-to-many topology (ie, that the PoC client units 801 and also the other PoC client units 806 all communication data from the other PoC client units 806 that is, that everyone clearly hears everyone).

Analogous to the embodiments described above, for example analogous to the steps 413 and 415 in 4 , is between the GM server computer 803 and the location server computer 804 a first SUBSCRIBE NOTIFY message pair 833 for each PoC client unit of the other PoC client units 806 exchanged, so, as above with respect to 4 described, the GM server computer 803 from the location server computer 804 always the current location status of the other PoC client units 806 is signaled.

Analog will be in step 810 between the GM server computer 803 and the presence server computer 805 a second SUBSCRIBE-NOTIFY message pair 834 exchanged, so the GM server computer 803 from the presence server computer 805 always above the current presence status of the other PoC client units 806 is informed, analogous to the embodiments described above.

In step 811 There is a PoC session between the first PoC client unit 801 and the other PoC client units 806 ,

• – an der bestehenden PoC-Session teilnehmen
• – sich im Umkreis von 3km des Berliner Alexanderplatzes befinden (in diesem Beispiel das erste Kriterium) und
• – deren Presence-Status "Taxi frei" ist (in diesem Beispiel das zweite Kriterium).

Now it is assumed that the first order for the carriage of a passenger, which is located at Alexanderplatz in Berlin, received at the taxi headquarters. The following steps will now be performed by the PoC client unit 801 within the existing PoC session a PoC communication with those of the other PoC client units 806 built that

• - participate in the existing PoC session
• - are within 3km of the Berlin Alexanderplatz (in this example the first criterion) and
• - whose presence status is "taxi free" (the second criterion in this example).

These PoC client units of other PoC client units 806 are hereinafter referred to as the PoC client units to be included.

In step 812 the PoC client unit sends a re-INVITE message 835 (designed according to a SIP re-INVITE) with a corresponding Content-Type (Application / Criteria + XML, compare Table 2), by means of which the first criterion and the second criterion are specified, to the PoC control server ner 802 , The re-INVITE message 835 contains in one embodiment a unique PoC communication identification (PK_id_rop). In step 813 generates the PoC control server 802 a (separate) PoC communication identification (PK_id). In step 814 sends the PoC control server 802 a confirmation (illustrative as a preliminary answer) to the PoC client unit 801 in the form of a 183-session-processing message 836 (designed according to SIP 183 session processing), by means of which also the PoC communication identification PK_id is signaled.

A PoC communication identification is, for example, a port number which enables the unique addressing of an application for application-specific data. In one embodiment, there are two PoC communication identifications, for example, a PoC communication identification PK_id_prop on the PoC client unit side 801 and a PoC communication identification PK_id on the PoC control server computer side 802 ,

In step 815 sends the PoC control server 802 a SUBSCRIBE message 837 to the GM server computer 803 , by means of which the PoC communication identification PK_id, the first criterion and the second criterion are signaled.

As explained above, the GM server computer is 803 always about the current location status and the current presence status of each POC client unit of the other PoC client units 806 informed. Based on this information, the GM server computer determines 803 in step 816 All participating PoC client units, ie all PoC client units of the other PoC client units 806 that meet the first criterion and the second criterion.

The participating PoC client units 806 are specified by the GM server computer in the current list by the group members (current_member_list). In step 817 sends the GM server computer 803 a NOTIFY message 838 to the PoC control server computers 802 by which it displays the current list of group members, which is the current list of group members to the PoC communication, by the ones in the SUBSCRIBE message 837 contained PoC communication identification PK_id is signaled.

The steps 818 and 819 are optional. In step 818 signals the PoC server computer 802 by means of a first MESSAGE message 839 the PoC client unit 801 which PoC client units of the further PoC client units 806 meet the first criterion and the second criterion. In another embodiment, the PoC control server computer signals 802 only the number of PoC client units to be included, ie the number of further PoC client units 806 that meet the first criterion and the second criterion (#_of_members).

In step 819 signals the first PoC client unit 801 whether to establish a PoC communication with the PoC client units specified by the current list of group members. In this example, it is assumed that no PoC communication is to be established with the PoC client units specified by the current list of group members. For example, the current list of PoC client units has the specification of 100 PoC client units, and the user in the taxi center decides that these are too many.

Accordingly, the PoC client unit sends 801 in step 819 a second MESSAGE message 840 to the PoC control server computer 802 by which it is specified that no PoC communication should be established with the PoC client units specified by the current list of group members (accept = no). Furthermore, the second MESSAGE message contains 840 modified criteria (criteria update), for example the change of the first criterion that the participating PoC client units should not be located within three kilometers of the Berlin Alexanderplatz, but within a radius of one kilometer of the Berlin Alexanderplatz. According to the modified criteria is analogous to the steps 815 . 816 and 817 In particular, a third new SUBSCRIBE NOTIFY message pair is identified 841 between the PoC control server 802 and the GM server computer 803 replaced.

Analogous to step 818 becomes the PoC client unit 801 the (new) current list of group members signals (not shown). Now it is assumed that PoC communication is to be established with the PoC client units specified by the new current list of group members. Accordingly, the PoC client unit sends 801 in step 821 a third MESSAGE message 842 to the PoC control server computer 802 , by means of which the PoC client unit 801 specifies that one PoC communication with the participating PoC client units (which meet the modified criteria) should be established (accept = yes).

By means of a PK_start message 843 signals the session controller 807 in step 822 the media mixer 808 that a new PoC communication was generated within the existing PoC session. The PK_start message 843 contains the PoC communication identification PK_id of the generated PoC communication and the current list of group members.

In step 823 confirms the media mixer 808 the receipt of the PK_start message 843 by means of an OK message 844 , In step 824 sends the PoC control server 802 in response to the re-INVITE message 835 a 200 OK message 845 ,

In step 825 sends the PoC client unit 801 a floor request message 846 to the PoC control server computer 802 , whereby it requests the language right, ie the right to send communication data, in the context of the generated PoC communication. The floor request message 846 contains the PoC communication identification PK_id of the generated PoC communication.

In step 826 it is decided if the PoC client unit 801 the language right is granted, this can be done by the session controller 807 or the media mixer 808 Therefore, messages may be exchanged between the session controller 807 and the media mixer 808 exchanged or the floor request message 846 gets directly to the media mixer 808 Posted. It is believed that the PoC client unit 801 the language right is granted. Accordingly, send in step 827 the media mixer 808 or in step 828 the session controller 807 , depending on which functional unit of the PoC control server computer 802 the language right awards a floor-granted message 848 to the PoC client unit 801 , by means of which the PoC client unit 801 the language right is granted.

In step 829 gets from the session controller 807 or in step 830 from the media mixer 808 (depending on which functional unit of the PoC control server computer 802 the language right granted) a Floor Taken message 849 sent to all participating PoC client units, by means of which the participating PoC client units, ie the PoC client units of the other PoC client units 806 , which are specified by means of the current list of group members, is signaled that the language right in the context of PoC communication by the in the Floor Taken message 849 contained PoC communication identification PK_id is specified, the voice right to the PoC client unit 801 was awarded.

In step 831 now sends the PoC client unit 801 communications data 850 in the context of the generated PoC communication, which is specified by the PoC communication identification PK_id, to the media mixer 808 for forwarding to participating PoC client unit. In step 832 directs the media mixer 808 the communication data 850 to the participating PoC client units through which he will step in 822 previously informed.

If another order arrives in the taxi center, regardless of the PoC communication generated, another PoC communication is carried out analogously to step by means of a re-INVITE message 812 started. In this way, the taxi center can lead to each order independent, independent of the other orders PoC communication within the existing PoC session.

By Generate further PoC communications within existing ones PoC session can also sub-group communications parallel to group communications or within group communication be realized, involving only a part of the members of a group participate, such as "Whispering" or "Sidebars".

9 shows a message flow diagram 900 according to an embodiment of the invention.

Analogous to those related to 8th The message flow described in the 9 illustrated message flow between a PoC client unit 901 (a taxi center), a PoC control server computer 902 who is a session controller 907 and a media mixer 908 has a GM server computer 903 , a location server machine 904 , a presence server computer 905 and other PoC client units 906 (by taxi drivers) instead.

The embodiment described below is a variant of with reference to 8th be written embodiment.

The steps 909 . 910 and 911 are analogous to the steps 809 . 810 and 811 ,

In step 912 sends the PoC client unit 901 instead of a re-INVITE message 835 as in step 812 a floor request message 934 to the PoC control server computer 902 ,

In the steps 913 and 914 . 916 and 917 in the event that the media mixer 908 The language rights management regulates messages between the session controller 907 and the media mixer 908 replaced.

The steps 915 . 918 to 927 become analogous to the news 813 to 823 performed (in step 918 however, an OK message is sent, not as in step 814 a 183-session-processing message). In this embodiment, the 200 OK message 845 not sent, which is the answer to the re-INVITE message 835 which is according to the in 9 message flow is not sent. Further, the floor request message 846 not sent, there already in step 912 the floor request message 934 was sent. Similarly, the step is omitted 826 , Analogous to the steps 827 and 828 will in the steps 929 and 928 a floor-granted message 935 to the PoC client unit 901 sent the response to the floor request message 934 is. The next steps 930 - 933 are analogous to the steps 829 - 832 ,

Analogous to those related to 6 and 7 described processes can also in the embodiments according to 8th and 9 Group members join a group or leave a group. This can be similar to with regard to 6 and 7 and will not be explained in detail.

In another embodiment is the communications service within which the invention is used , the 3GPP (3rd Generation Partnership Project) specified "IMS Conferencing". This is a conference communication service on the IMS (Internet Protocol based Multimedia Subsystem) architecture based. The functionality of a GM server computer in this case is a conference policy server covered. A conference policy server manages the rules and states used in a conference by means of a conference policy document.

A Conference client unit in this embodiment sends criteria according to which a group of conference participants should be created dynamically, according to CPCP (Conference Policy Control Protocol) to the Conference Policy Server, which meets the criteria in an appropriate format in the Conference Policy document stores. In one embodiment holds the Conference Policy server both the criteria and the list the current group members in the Conference Policy document. To generate the list of information required by current group members (for example as above presence information and Location information), the Conference Policy server determines analogously to the embodiments described above.

In the above explained embodiments only the use case was handled, that possible participants (or corresponding client units) to a communication service (for example, a PoC session) when (or once) they meet specified criteria.

The However, invention is also applicable if possible participants (or equivalent Client units) are not invited, but actively themselves dial have to, i.e. have to initiate their participation themselves. An example of this is a Chat session (or PoC session) to which users must dial in themselves.

For example, a user wishes to dial in to a PoC control server computer providing a PoC session by means of a client unit he uses, for example by sending a dial-in message according to SIP INVITE in order to be able to participate in the PoC session. Analogous to the above exemplary embodiments, criteria are defined and the PoC control server computer checks, for example analogous to above by requesting a GM server computer, whether the user who wishes to dial in fulfills the defined criteria. Only if the user (or the client unit used by him) meets the criteria, the dial-in is accepted and (for example, according to SIP 200 OK) and the user is then a participant in the PoC session. If the user does not meet the criteria, the dial-in message is answered in the negative, for example by means of a refusal message according to SIP REJECT, the may also include an indication of the reason for the refusal, and the user will not be a participant in the PoC session.

• [1] 3GPP TS 22.250 V6.0.0 (2002-12), "IP Multimedia Subsystem (IMS) group management"
• [2] Push to Talk over Cellular (PoC); List Management and Do-not-Disturb; PoC Release 2.0
• [3] RFC "Hypertext Transfer Protocol -- HTTP/1.1"
• [4] RF3261 "SIP: Session Initiation Protocol"
• [5] RFC3265 "Session Initiation Protocol (SIP)-Specific Event Notification"
• [6] RFC3428 "Session Initiation Protocol (SIP) Extension for Instant Messaging"
• [7] WO 00/16209
• [8] WO 02/103570 A1

This document cites the following publications:

• [1] 3GPP TS 22.250 V6.0.0 (2002-12), "IP Multimedia Subsystem (IMS) group management"
• [2] push to talk over cellular (PoC); List Management and Do-not Disturb; PoC Release 2.0
• [3] RFC "Hypertext Transfer Protocol - HTTP / 1.1"
• [4] RF3261 "SIP: Session Initiation Protocol"
• [5] RFC3265 "Session Initiation Protocol (SIP) -Specific Event Notification"
• [6] RFC3428 "Session Initiation Protocol (SIP) Extension for Instant Messaging"
• [7] WO 00/16209
• [8] WO 02/103570 A1

100

Message flow diagram

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PoC client units

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GM server computer

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PoC server computer

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process steps

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news

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Message flow diagram

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GM client unit

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ServiceX client unit

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ServiceX server unit

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GM server unit

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process steps

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news

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communication system

301-303

PoC client units

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interface

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PoC subscriber server computer

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PoC control server computer

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Chair

308

GM (Group Management) -Serverrechner

309

Presence server computer

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Message flow diagram

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PoC client unit

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PoC control server computer

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GM server computer

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Location server computer

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Presence server computer

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Further PoC client units

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process steps

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Message flow diagram

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PoC client unit

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PoC control server computer

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GM server computer

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Location server computer

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Presence server computer

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Further PoC client units

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process steps

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news

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PoC client unit

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PoC control server computer

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GM server computer

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Location server computer

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Further PoC client units

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New added PoC client unit

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process steps

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news

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PoC client unit

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PoC control server computer

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GM server computer

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Location server computer

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Further PoC client units

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leaving PoC client unit

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process steps

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news

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PoC client unit

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PoC control server computer

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GM server computer

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Location server computer

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Presence server computer

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Further PoC client units

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session controller

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Media mixer

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process steps

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news

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PoC client unit

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PoC control server computer

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GM server computer

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Location server computer

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Presence server computer

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Further PoC client units

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session controller

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Media mixer

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process steps

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Claims (18)

Communication system with a communication service client unit, another Communication service client units, a communication service server unit and a server unit, in which - the Communication service client unit is set up, one or to generate several messages which are at least one criterion contained by the other communication service client units each fulfilled will or will not be fulfilled and the request for the provision of the communication service and a specification that the other communication service client units, that meet the criterion Be participants in the provided communication service; - the server unit is set up, a list of the other communication service client units, that meet the criterion to generate and transmit to the communication service server unit; and - the Communication service server unit is set up, the communication service with the communication service client unit and the other communication service client units using the Fulfill criterion, as Provide participants. The communication system of claim 1, wherein the request in a first message containing one or more messages is transmitted from the communication service client unit to the communication service server unit becomes. Communication system according to claim 2, wherein the criterion in a second message containing one or more messages is transmitted from the communication service client unit to the server unit becomes. Communication system according to claim 2, wherein the criterion in the first message containing one or more messages is. Communication system according to one of claims 1 to 4, wherein the server unit is arranged to transmit to a third party at least one information server unit for generating the list of the further communication service client units, which contains the request for information, which are required to check whether the other communication service client units meet the criterion. The communication system according to claim 5, wherein the information server unit is a presence server unit or a location server unit. Communication system according to one of claims 1 to 6, wherein the one or more messages further include another list contains a portion of the other communication service client units, and one of the other communication service client units only then Participant of the provided communication service should be if it is listed on the further list and the criterion Fulfills. Communication system according to one of claims 1 to 7, wherein the communication service is a communication service, based on SIP. Communication system according to one of claims 1 to 8, wherein in the one or more messages the at least one Criterion specified according to XML becomes. Communication system according to one of claims 1 to 9, wherein the server unit is set up in the course of deployment the communication service the list of other communication service client units, that meet the criterion on validity to check and If necessary, update and update the updated list Communication service server unit to submit. The communication system of claim 10, wherein the communication service server unit is set up according to the updated List to change the participants of the communication service. Communication system according to one of claims 1 to 11, wherein the communication service in the context of another communication service is provided by the communication service server unit provided. Communication system according to one of claims 1 to 12, wherein the communication service is a PoC communication service, a communication service for sending instant messages, an MMS communication service or a conference communication service is. Method for operating a communication system, which communication system is a communication service client unit, more Communication service client units, a communication service server unit and a server unit wherein, according to the method The communication service client unit generates one or more messages which are at least one criterion contained by the other communication service client units respectively Fulfills will or will not be fulfilled and the request for the provision of the communication service and a specification that the other communication service client units, that meet the criterion Be participants in the provided communication service; - the server unit a list of other communication service client units that fulfill the criterion and transmitted to the communication service server unit; and The communication service server unit, the communication service with the communication service client unit and the others Communication service client units, that meet the criterion as participants. Server unit of a communication system, which Communication system communication service client units and a Communication service server unit, wherein the server unit is set up - one Message containing at least one criterion from the communication service client units each fulfilled will or will not be fulfilled is to receive; and - one List of communication service client units that meet the criterion fulfill, to generate and transmit to the communication service server unit. A method of operating a server unit of a communication system, the communication system comprising communication service client units and a communication service server unit, wherein according to the method the server unit - a message containing at least one criterion supplied by the communication service client Units is met or not met, receives; and A list of the communication service client units meeting the criterion is generated and transmitted to the communication service server unit. Communication service client unit of a communication system, which communication system further communication service client units, a communication service server unit and a server unit wherein the communication service client unit is set up or to generate several messages which are at least one criterion contained by the other communication service client units respectively Fulfills will or will not be fulfilled and the request for the provision of the communication service and a specification that the other communication service client units, that meet the criterion Participants of the provided communication service should be. Method for operating a communication service client unit of a Communication system, which communication system further communication service client units, a communication service server unit and a server unit, wherein according to the method the communication service client unit generates one or more messages which are at least one criterion contained by the other communication service client units respectively Fulfills will or will not be fulfilled and the request for the provision of the communication service and a specification that the other communication service client units, that meet the criterion Participants of the provided communication service should be.