Abstract:
A communications network system and a corresponding method for starting an AoC service of a user are disclosed. The system comprises a control means for sending a protocol message comprising a MIME indication of an AoC application to a user equipment (UE). The user equipment receives the protocol message and activates the AoC application by using the MIME indication.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to starting an AoC (Advice of Charge) service of a user in a communications network system, and in particular in an All-IP network system.  
         BACKGROUND OF THE INVENTION  
         [0002]    AoC (Advice of Charge) is a service which provides the means by which a user equipment may indicate the charge that will be made for the use of telecommunication services. In other words, AoC is a user-friendly service which informs an end-user about the cost of a transaction. In All-IP (All-Internet Protocol) networks this kind of service is even more important since there can be several application servers with different charges in the same transaction.  
           [0003]    However, due to the fragmented network architecture, AoC cannot be implemented in All-IP networks in the same way as in GSM (Global System for Mobile communications).  
         SUMMARY OF THE INVENTION  
         [0004]    It is therefore an object of the present invention to provide an implementation of AoC which is also suitable for an All-IP network.  
           [0005]    According to an aspect of the present invention, this object is achieved by a method of starting an AoC service of a use in a communications network system, comprising the steps of  
           [0006]    sending a protocol message comprising a MIME indication of an AoC application from a control means to a user equipment UE; and  
           [0007]    receiving the protocol message at the user equipment and activating the AoC application in the user equipment by the MIME indication.  
           [0008]    According to another aspect of the present invention, the above-mentioned object is achieved by a communications network system for starting an AoC service of a user, comprising:  
           [0009]    a control means for sending a protocol message comprising a MIME indication of an AoC application to a user equipment UE;  
           [0010]    wherein the user equipment receives the protocol message and activates the AoC application by using the MIME indication.  
           [0011]    The protocol message may further comprise charging parameters of a service application, and the AoC application may be activated with the charging parameters received at the user equipment.  
           [0012]    Moreover, in a protocol message, a service usage request for another service application may be sent from the user equipment to the control means, and the control means may, in a protocol message, return cost information of the application service usage to the user equipment. Then, the user equipment can update the AoC information in accordance with the returned cost information.  
           [0013]    When the control means receives the service usage request from the user equipment, it may fetch the cost information about the other service application and calculate new charging parameters and send the new charging parameters as cost information to the user equipment, or just send an add-on parameter set as cost information to the user equipment.  
           [0014]    In case of receiving the add-on parameter set, the user equipment combines the initially received charging parameters with the add-on parameter set.  
           [0015]    All the protocol messages sent between the user equipment and the control means may be SIP messages or messages of any protocol capable of carrying MIME encoded information between the control means and the UE in a communications network system, e.g. H.323 protocol.  
           [0016]    Furthermore, the protocol message comprising the MIME indication may be sent at the beginning of each call.  
           [0017]    In addition, the protocol message comprising the MIME indication may be sent when the charging parameters are available in the control means.  
           [0018]    According to a further aspect of the present invention, the above-mentioned object is achieved by a control means in a communications network system, wherein said control means is arranged to send a protocol message comprising a MIME indication of an AoC application to a user equipment UE having AoC service.  
           [0019]    According to the present invention, a simple and practical implementation of AoC in All-IP networks can be provided. Different AoC applications can be used, which AoC applications can have different MIME versions. AoC applications can be downloaded to the user equipment depending on what kind of charging agreement is selected. If needed, the charging agreement can be changed to be call-specific.  
           [0020]    In the following the present invention will be described by way of a preferred embodiment thereof with reference to the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]    [0021]FIG. 1 shows a schematic block diagram of a part of an All-IP network architecture; and  
         [0022]    [0022]FIG. 2 shows a signaling diagram illustrating an AoC mechanism according to an embodiment of the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0023]    The idea of the present invention is to use MIME (Multipurpose Internet Mail Extensions) as an indication for AoC. Initially, the MIME structure was developed for Internet e-mail, but it has a number of features which make it useful to provide a common structure for encoding multimedia data as a MIME-encapsulated message.  
         [0024]    The MIME AoC indication is sent to the user equipment in a protocol message, for example a SIP message. SIP (Session Initiation Protocol) is an application-layer control (signaling) protocol for creating, modifying and terminating sessions with one or more participants. These sessions include Internet multimedia conferences, Internet telephone calls and multimedia distribution. Members in a session can communicate via multicast or via a mesh of unicast relations, or a combination of these. SIP invitations used to create sessions carry session descriptions which allow participants to agree on a set of compatible media types. SIP supports user mobility by proxying and redirecting requests to the user&#39;s current location. Users can register their current location. SIP is not tied to any particular conference control protocol. SIP is designed to be independent of the lower-layer transport protocol and can be extended with additional capabilities.  
         [0025]    As can be seen from the foregoing, SIP is a flexible protocol which enables new methods to implement AoC. According to the present invention, MIME is used as an indication to AoC. The MIME AoC indication may be transferred to the user equipment in a SIP message. However, other protocol messages offering similar possibilities can be used, which can be defined between the required interfaces. When the protocol message including the MIME AoC indication is received at the user equipment, MIME activates the indicated AoC application in the user equipment.  
         [0026]    [0026]FIG. 1 shows part of an All-IP network architecture. In case a user has a call with a service application in a multimedia IP network, the user equipment UE accesses an access network. From the access network, the call connects to a serving node in a core network, for example to an SGSN (Serving GPRS Support Node) in a GPRS (General Packet Radio Service) network. From the SGSN, the call is directed to a gateway, such as an GGSN (Gateway GPRS Support Node) in GPRS, for routing the call to the multimedia IP network. A control means, for example a CSCF (Call State Control Function), performs signaling between the IP network and the GGSN for providing services to the user equipment.  
         [0027]    An embodiment of the present invention will be described in the following by referring to FIG. 2.  
         [0028]    [0028]FIG. 2 shows a signaling diagram illustrating the AoC mechanism according to an embodiment of the present invention. The CSCF has information that a user has an AoC service. When charging information is received in the CSCF for a service application in the multimedia IP network, the CSCF sends a SIP message comprising MIME AoC information and charging parameters to the user equipment UE (communication  1  in FIG. 2). Then, the UE starts AoC with the given charging parameters (block  2  in FIG. 2). As a result, information about the cost of the application can be presented to the user.  
         [0029]    In case the user wishes another application, for example an application X, a service usage request message is sent from lo the UE to the CSCF (communication  3  in FIG. 2). Thereupon, the CSCF makes a cost information request at the application X in the IP network (communication  4  in FIG. 2). When the CSCF gets returned the cost information from the application X, the CSCF either combines the tariffs or just sends add-on tariff (block  6  in FIG. 2) to the user equipment in a cost of the application service usage message comprising a MIME AoC indication in order to carry the message in the user equipment to the right application (communication  7  in FIG. 2). Finally, the UE updates the AoC information in accordance with the received new charging parameter set (block  8  in FIG. 2). When the UE receives only the add-on parameter set, it combines the add-on parameters with the initially received charging parameters.  
         [0030]    The CSCF may send the SIP message comprising the MIME informing AoC and the charging parameters at the beginning of each call to the user equipment.  
         [0031]    The present invention is especially useful in All-IP networks but not limited thereto.  
         [0032]    While the invention has been described with reference to a preferred embodiment, the description is illustrative of the invention and is not to be construed as limiting the invention. Various modifications and applications may occur to those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims.