Abstract:
A method, system and Application Server (AS) for distributing Push-To-Talk (PTT) voice and multimedia messages to communities of subscribers, using a definition os PTT groups. First, a PTT group of subscribers is created in the AS, either by one of the members or by a content provider server. Then, the subscribers register their interest in receiving PTT messages related to the created group, for example by joining a Session Initiation Protocol (SIP) related to that group. Finally, the content provider server sends a PTT message destined to the PTT group, the message comprising voice and/or multimedia information, such as for example news, stock quotes, sport updates, weather or commercial information. The message is received by the AS, which distributes it to the registered subscribers of the PTT group using its definition of the PTT group.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to the distribution of voice and multimedia information using Push-To-Talk (PTT) subscribers&#39; group.  
           [0003]    2. Description of the Related Art  
           [0004]    Push-To-Talk (PTT) defines a functionality wherein a user can simply push a button (or click or otherwise activate a key) of his communication terminal in order to have its voice being transmitted from its terminal to one or more other communications terminals. A wide range of variants of the PTT functionality have been implemented in different telecommunications systems in the industry, ranging from the simple radio walkie-talkies to more complex software applications running on top of Personal Computers (PCs) connected via the Internet, further to cellular telecommunications systems, wherein the subscribers make use of the cellular system to send their voice message.  
           [0005]    Nowadays, PTT is been also implemented in the cellular General Packet Radio Service (GPRS) systems. According to this implementation, GPRS users receiving the transmission hear the sender&#39;s voice automatically without having to answer the call. In this implementation, PTT is based on the IP Multimedia System (IMS), a technology standardized by the Third Generation Partnership Projects (3GPP). IMS adds two features on top of the packet-switched domain: it gives the ability to find a person via Session Initiation Protocol (SIP) to initiate a session, and provides the ability to integrate new revenue services, such as PTT.  
           [0006]    Reference is now made to FIG. 1. a  (Prior Art) that shows a simplified high-level network diagram of a system  10  with an existing PTT functionality that may be implemented in a cellular GPRS network. Shown in FIG. 1 are, first, four (4) User Equipments (UE): UE 1    12 , UE 2    14 , UE 3    16 , and UE 4    18 . UE 1    12  is provided wireless cellular service via a first wireless network  20 , while UE 2    14 , UE 3    16 , and UE 4    18  receive wireless cellular service via a second wireless network  22 . Both networks  20  and  22  are connected to a Session Initiation Protocol (SIP) Application Server (AS)  24 , which comprises a PTT module  26  responsible for the provision of the PTT service to the subscribers of the networks  20  and  22 . In the implementation shown in FIG. 1. a , first, a subscriber, such as for example the subscriber of the UE 2  may define a group of subscribers, comprising, for example, subscribers of the UE 1 , UE 2 , UE 3 , and UE 4 . Then, the subscribers may register with the PTT module  26  of the application server  24  to inform the network that they are ready to receive PTT messages related to that group. Finally, when anyone of the registered group subscribers pushes the button to send the PTT message, his voice is transmitted via its respective network  20  or  22  via the AS  24  to all the remaining registered members of the group.  
           [0007]    In this manner, small communities of persons that are defined in the same PTT group can communicate with each other by making use of the PTT functionality.  
           [0008]    Reference is now made to FIG. 1. b  (Prior Art) illustrating a high-level flowchart diagram of a flow of actions performed for sending a PTT message in the previously described network  10 . In action  100 , the first user creates the users group, then in action  102 , some, or all of the group&#39;s subscribers register with the AS  24  so that the network knows that they are ready to receive PTT messages. Finally, in action  104 , anyone of the registered users sends a PTT voice message to the other members of the group, and in action  106 , the PTT voice message is delivered to the targeted members of the group, and played on their terminals.  
           [0009]    Although there is no prior art solution as the one proposed hereinafter, the UK Patent Application GB 2,290,196 bears some relation with the present invention. In the UK Patent Application GB 2,290,196, there is disclosed a system for reducing access time in a PTT system. The system includes a unit with a list of ID numbers for members of a talk group held in memory. A paging command for a selected ID can be transmitted over a control channel, and a traffic channel is selected for further communication on receipt of a channel grant command. A second unit receives a paging command with an ID and a group channel grant command over the control channel and receives traffic over a traffic channel. The ID is compared with the ID for the second unit and the unit, which is being paged, is determined. An alert signal is generated in response to the paging command. A PTT command is input at a switch and a group call request is transmitted over the control channel. A central unit repeats the paging commands and traffic. Group call channel grant commands are transmitted in response to group call requests when a traffic channel is available. If the target unit PTT switch and is not operated within a preset time, the alert signal stops but a visual signal indicates someone has called.  
           [0010]    To date, the use of the PTT technology has been limited to the transmission of voice messages. Furthermore, the PTT functionality has been also used only for the transmission of voice information that originates from a subscriber&#39;s terminal. However, this concept has only limited applications. For example, the existing PTT service architecture does not allow non-voice information to be transmitted. Moreover, it prevents information originating from a variety of non-terminal sources to be transmitted to the groups of subscribers.  
           [0011]    Accordingly, it should be readily appreciated that in order to overcome the deficiencies and shortcomings of the existing solutions, it would be advantageous to have a new method and system for effectively allowing the transmission of voice and multimedia information from a third party content provider to a group of PTT subscribers. The present invention provides such a method and system.  
         SUMMARY OF THE INVENTION  
         [0012]    In one aspect, the present invention is a method for sending voice and multimedia information to subscribers of a telecommunications network, the method comprising the steps of:  
           [0013]    creating a Push-To-Talk (PTT) group of subscribers in the telecommunications network;  
           [0014]    receiving from a content provider server a PTT message destined to the PTT group; and  
           [0015]    distributing the PTT message to one or more subscribers of the PTT group.  
           [0016]    In another aspect, the present invention is a telecommunications network, comprising:  
           [0017]    a plurality of subscribers&#39; User Equipments (UEs);  
           [0018]    an Application Server (AS) storing a definition of a Push-To-Talk (PTT) group of subscribers that include one or more UEs from the plurality of subscribers&#39; UEs; and  
           [0019]    a content provider server;  
           [0020]    wherein the AS receives from the content provider server a PTT message destined to the PTT group, and distributes the PTT message to the one or more UEs of the PTT group.  
           [0021]    In yet another aspect, the present invention is an Application Server (AS) for use in a telecommunications network, the AS comprising:  
           [0022]    a group definition module for storing a definition of groups of User Equipments (UEs);  
           [0023]    a Push-To-Talk (PTT) module for providing PTT communication service to at least to certain UEs of the telecommunications network; and  
           [0024]    a content provider server;  
           [0025]    wherein the AS receives from the content provider server a PTT message destined to a selected one of the groups of UEs, and distributes the PTT message to one or more UEs that are members of the selected group. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0026]    For a more detailed understanding of the invention, for further objects and advantages thereof, reference can now be made to the following description, taken in conjunction with the accompanying drawings, in which:  
         [0027]    [0027]FIG. 1. a  (Prior Art) is a simplified high-level network diagram of an exemplary existing Push-To-Talk (PTT) functionality that may be implemented in a cellular General Packet Radio Service (GPRS) system;  
         [0028]    [0028]FIG. 1. b  (Prior Art) is a high-level flowchart diagram illustrative of a flow of actions performed for sending a PTT message;  
         [0029]    [0029]FIG. 2. a  is a simplified high-level network diagram of an exemplary PTT functionality implemented in a cellular system according to the preferred embodiment of the present invention;  
         [0030]    [0030]FIG. 2. b  is an exemplary table showing the subscribers&#39; group definition in the Application Server (AS) according to the preferred embodiment of the present invention;  
         [0031]    [0031]FIG. 3. a  is a first part of an exemplary nodal operation and signal flow diagram illustrative of a cellular system implementing the preferred embodiment of the present invention; and  
         [0032]    [0032]FIG. 3. b  is a second part of the exemplary nodal operation and signal flow diagram illustrative of a cellular system implementing the preferred embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0033]    The innovative teachings of the present invention will be described with particular reference to various exemplary embodiments. However, it should be understood that this class of embodiments provides only a few examples of the many advantageous uses of the innovative teachings of the invention. In general, statements made in the specification of the present application do not necessarily limit any of the various claimed aspects of the present invention. Moreover, some statements may apply to some inventive features but not to others. In the drawings, like or similar elements are designated with identical reference numerals throughout the several views.  
         [0034]    The present invention provides a new Push-To-Talk (PTT) service architecture along with corresponding method and system for allowing a content provider server to send voice and multimedia information to a subscribers&#39; group defined in an Application Server (AS). The present invention, allows for content provider server to connect to the AS, and to broadcast voice and/or multimedia information to group members.  
         [0035]    Reference is now made to FIG. 2. a , which is an exemplary high-level network diagram of a PTT functionality implemented in a cellular system  200  according to the preferred embodiment of the present invention. Shown in FIG. 2. a  are two wireless networks  202  and  204  that provide cellular access to User Equipments (UE) UE 1    206 , UE 2    208 , UE 3    210 , and UE 4    212 . The two wireless networks  202  and  204  each connect to an Application Server (AS)  214  that is responsible for providing one or more services for the subscribers of the UEs  206 - 212 . The AS  214  comprises a PTT module  216  that supports PTT service for said subscribers. The AS  214  may further comprise one or more groups definition module  218  where the subscriber groups information is stored.  
         [0036]    With reference being now made to FIG. 2. b , the groups definition module  218  may comprise one or more group information tables alike the group definition table  250  shown in FIG. 2. b , which illustrates how a subscriber group may be defined. The group definition table  250  preferably comprises a group ID  252  that uniquely identifies that group of subscribers, and a list of subscribers&#39; UEs that are members of the group. For each UE of the group, the group information table  250  may comprise an identifier  254   i , such as for example an SIP Uniform Resource Indicator (URI) with an email address of the subscriber, and optionally, an E.164 telephone number  264   i  of that UE. In some implementations, the E.164 telephone number  264   i  may also be part of the SIP URI.  
         [0037]    Reference is now made back to FIG. 2. a , wherein connected to the AS  214  is a content provider server  220  that may communicate with the AS  214  over the Internet  222 . According to the preferred embodiment of the invention, the third party content provider  220  may use the PTT service functionality of the AS  214  for sending information of various types, such as for example commercial advertisements, news, stock quotes, sport updates or news, etc, to the group subscribers of the UEs  206 - 212 , in the form of PTT voice or multimedia messages. This is achieved by using the subscribers&#39; group definition of the group module  218  of the AS  214 .  
         [0038]    Reference is now made to FIG. 3, which is an exemplary nodal operation and signal flow diagram of a cellular system  300  implementing the preferred embodiment of the present invention that allows a content provider  302  to send voice or multimedia information to a community of UEs using the PTT service functionality defined in the AS  214 . In FIG. 3, similar network functionalities are defined with the same numerals as the once previously used in relation to the FIG. 2.  
         [0039]    In the exemplary scenario shown in FIG. 3, firstly, a PTT subscribers group has to be defined. According to a first exemplary scenario shown in FIG. 3. a , the subscriber of the UE 1    206  is the one who initiates the creation of the PTT group, by sending Short Message Service (SMS) Messages  310 ,  312 , and  314  to subscribers of UE 2    208 , UE 3    210 , and UE 4    212 , for inviting them in joining a new PTT group.  
         [0040]    It is to be noted that signalling relevant to the first exemplary scenario, wherein a subscriber is the initiator of the creation of the subscribers&#39; group is represented throughout FIG. 3 with plain lines, a opposed to the dotted lines that relate to a second exemplary scenario that is yet to be discussed further in the present description. With reference to the first exemplary scenario described in FIG. 3. a , a group identifier  315  that uniquely identifies the newly created group is included in each of the messages  310 - 314 . In actions  316 ,  318 , and  320 , the subscribers of UE 2    208  and UE 3    210  accept the invitation to join the new group, while subscriber of the UE 4    212  declines. Reply messages  322 - 326  with the appropriate response are sent back from the invited subscribers to the UE 1    206 , which in action  330  sends via an XML message the definition of the newly created group to the AS  414 . The message  330  comprises the group identifier  315  and the UE identities  332 ,  334  and  336  of the PTT group members UE 1    206 , UE 2    208  and UE 3    210  respectively who accepted to be in the group. In action  340 , the AS  214  stores the group definition information received in message  330  in a group definition module  218  and, in action  342 , replies back to the UE 1    206  with an acknowledgment message confirming the establishment of the new PTT group. Finally, the UE 1    206  sends two SMS acknowledgment messages  344  and  246  for confirming the establishment of the new PTT group to the other group members UE 2    208  and UE 3    210  respectively.  
         [0041]    According to an optional implementation of the first exemplary scenario of the preferred embodiment of the invention, although the PTT subscribers group is already created at this stage, PTT messages cannot be sent without first having the group members UEs to register their interest in receiving PTT messages from that group. For this purpose, a group member, say UE 3    210 , is the first to send a SIP INVITE message with the group ID and an authorization request to the AS  214 , action  350 , for registration with the group. In action  352 , the AS  214  performs an authentication (provided the UE needs further authentication) and/or an authorization of the UE 3    210 , and if the result is a success, replies back to the UE 3    210  with a  200  OK message  354  for confirming the registration of the UE 3    210  with the group. The UE 3    210  replies with an acknowledgement message  355 . At that moment, the UE 3    210  is ready to send or receive PTT messages in that PTT group.  
         [0042]    At different moments, other group members, such as UE 1    206  and UE 2    208  may perform similar actions  356 - 367  and get registered with the AS  214  for PTT communications of that group, so that at a given point in time, all UE 1    206 , UE 2    208 , and UE 3    210  are ready to send or receive PTT communications in that group.  
         [0043]    According to a second exemplary scenario of the preferred embodiment of the present invention, the subscribers&#39; group may be created in other manner as well than by one of the subscribers itself. For example, the content provider server  302  may be the one initiating the group creation for the purpose of sending information of various kinds to a community of subscribers. According to this variant, with reference being still further made to FIG. 3. a , instead of having the UE 1    206  to send messages  310 - 314 , it is the content provider server that sends equivalent messages  390 - 396  to UEs  206 - 212  for inviting them to join the new group. In this scenario, it is assumed that UE 1    206 , UE 2    208 , and UE 3    210  accept the invitation, actions  313 ,  316 ,  318 , while UE 4    212  declines again, action  320 . Actions  398 - 404  are then performed, which are analogous to the ones of steps  322 - 330 , previously described, except for the fact that in the presently described second exemplary scenario, it is the content provider server, instead of the UE 1    206 , who is the initiator of the group creation. Messages  406 - 410  complete and confirm the creation of the new PTT group.  
         [0044]    Once the content provider  302  creates the group, it may further invite the member UEs  206 ,  208  and  210  to register their interest in receiving PTT messages of the group, by sending SIP INVITE messages  420 - 424  to the three group members. It is assumed that all respond positively to the content provider with 200 OK messages  426 - 430 , and that acknowledgement messages  432 - 436  finalise the registration of the group members.  
         [0045]    Once any one of the first or second scenario (or any combination there between) is used for creating the subscribers&#39; group, and for registration of the interest of the members in receiving or sending PTT messages, in action  370 , the content provider server  302  may send a media message comprising a media file and the group ID  315 , for the purpose of reaching the group members with the media message. The media message may comprise various kinds of information, such as for example but not limited to, news, sport scores, matches updates, commercial advertisement, announcements, etc, and may be sent to the AS  214  via a Web Service  374 . The AS  214  resolves the subscribers group using the group ID  315 , i.e. extracts the identities of the group members from the group information module  218  based on the received group ID  315 , action  375 , and sends the media file in actions  376 ,  378 , and  380  to the group members UE 1    206 , UE 2    208 , and UE 3    210 , which each plays the file upon receipt, actions  382 ,  384 , and  386  respectively.  
         [0046]    In an alternate variant of the invention, in action  370 , the content provider server  302  may rather send a media message comprising a link  371  to a media file rather than the entire media file itself, in order to save communications resources. The media message with the link, for example in the form of a SIP Uniform Resource Indicator (URI), may be sent to the AS  214  via the same Web Service  374 . The AS  214  resolves the subscribers group using the group ID  315  as described hereinbefore, action  375 , further retrieves the media file from the SIP URI, action  377 , and finally sends the Media file in same actions  376 ,  378 , and  380  to the group members UE 1    206 , UE 2    208 , and UE 3    210 , which each plays the file upon receipt, actions  382 ,  384 , and  386  respectively.  
         [0047]    Based upon the foregoing, it should now be apparent to those of ordinary skills in the art that the present invention provides an advantageous solution, which offers easy communication access for a third party content provider to PTT group subscribers for the purpose of allowing the transmission of voice and multimedia PTT messages to communities of users. Although the system and method of the present invention have been described in particular reference to certain exemplary scenarios, it should be realized upon reference hereto that the innovative teachings contained herein are not necessarily limited thereto and may be implemented advantageously with many alternative call scenarios, and any applicable radio telecommunications standard. It is believed that the operation and construction of the present invention will be apparent from the foregoing description. While the method and system shown and described have been characterized as being preferred, it will be readily apparent that various changes and modifications could be made therein without departing from the scope of the invention as defined by the claims set forth hereinbelow.  
         [0048]    Although several preferred embodiments of the method and system of the present invention have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the spirit of the invention as set forth and defined by the following claims.