METHOD AND SYSTEM FOR THE PROCESSING OF TARIFF DATA

Abstract: Method and system for the processing of charge messages in a telecommunication system comprising a registering point (RP) where received charge messages are distinguished from each other on the basis of tariff category and signalling point code, a first telephone exchange (AX), to which the calling subscriber is connected, and a second telephone exchange (BX), to which the called subscriber is connected and which telephone exchange uses charge calculation based on charge messages of both the originating side (O) and the terminating side (T), a charge message being sent during call set-up from the originating side to the registering point. According to the invention, a charge message received from the terminating side (T) is checked on the originating side (O) of the second telephone exchange (BX); the charge data of the originating side (O) and terminating side (T) are combined if they bear similarities; the charge message is modified to form a replacing charge message that contains the combined charge data; and the replacing charge message is sent to the registering point (RP).

Description: METHOD AND SYSTEM FOR THE PROCESSING OF TARIFF DATA The present invention relates to the processing of tariff data for a telecommunication connection. In particular, the invention concerns a new and im- proved method and system for the transmission of charge data to a registering point. BACKGROUND OF THE INVENTION A prior-art method for charging for a tele- communication connection is based on CHG messages (CHarGe message) . CHG messages are used to transmit call tariff information, which is stored in charging records (CDR) . This method is used e.g. in ISDN networks and it necessitates the use of ISUP2 signalling (ISUP2, ISDN user part, version 2) . The charge message is a tariff message generated in the B-subscriber ' s telephone exchange and transmitted to the registering point during call set-up. The registering point is often the A-subscriber ' s telephone exchange. It may also be a telephone exchange between two networks or any other telephone exchange to which the subscribers are connected. In this context, A- subscriber means the committer of the connection, and B-subscriber means the subscriber with whom a connection is to be set up. To verify that the charge data have been received at the registering point and that the registering point has approved them, an acknowledgement or CHGA (CHarGe Acknowledgement) message is sent to the network element which sent the charge message. If the network element which has sent a CHG message does not receive a CHGA message within a certain length of time, then the telecommunication connection is disconnected. The charge data can be changed during the connection by sending a replacing charge message (replacing CHG tariff) to the registering point. This message transmitted to the registering point contains a new value and an indicator specifying the quantity to be replaced with the new value. The CHG messages are transmitted through all the telephone exchanges along the connection to the registering point, which stores them for use in calculation. A signalling point code included in the charge message is used in acknowledging the message to direct the acknowledgement to the exchange which sent the charge message . The signalling point code contains the addresses of the receiving network element and the network element which has sent the message. Moreover, charge messages contain an indication of the tariff category to be used, of which there is a limited number in use. From the charge and call data accumulated at the registering point, a charging centre later calculates the price to be charged to the subscriber. In call set-up referred to above, problems are encountered in situations where charge messages of the same tariff category are sent from both the originating and terminating sides. In a call for which charge messages are generated on the originating and terminating sides of the same network element, the signalling point codes for the messages are the same. If the tariff categories of the messages are also the same, then the registering point is unable to distinguish the messages from each other and the call is disconnected. The object of the present invention is to eliminate the drawbacks described above or at least to significantly alleviate them. A specific object of the present invention is to disclose a new type of method and system for transmitting charge messages to a registering point in a I situation where messages are sent from the originating and terminating sides of the called subscriber's telephone exchange . BRIEF DESCRIPTION OF THE INVENTION The present invention concerns a method for the processing of CHG messages (CHarGe messages) in a telecommunication system. This telecommunication sys- tern comprises a registering point where received charge messages are distinguished from each other e.g. on the basis of tariff category and signalling point code. Moreover, the system comprises a first telephone exchange, to which the A- subscriber is connected, and a second telephone exchange, to which the B-subscriber is connected. The second telephone exchange uses charge calculation based on charge messages of both the originating and terminating sides. In this charge calculation, a charge message is sent from the origi- nating side to the registering point during the establishment of the connection. In the method of the invention, a charge message received on the originating side from the terminating side is checked and the charge data for the originating and terminating sides are combined if they bear a similarity to each other. After this, according to the invention, the charge message is modified to form a replacing charge message containing the combined charge data, and the message is sent to the registering point . In an embodiment of the method, the tariff data sent in the charge message from the originating side to the registering point and the tariff data sent m the charge message from the terminating side are added together if the tariff categories of these mes- sages are the same. The sum is sent m the replacing charge message to the registering point . In a preferred embodiment, an acknowledgement message is sent from the originating side to the terminating side aζter the registering point has acknowl- edged the replacing charge message sent from the originating side. This is done because the terminating side waits for an acknowledgement before continuing its functions in the normal manner. According to the invention, all charge messages received by the originating side from the termi- nating side in which the charge data bear similarities to the charge data sent to the registering point can be combined. The registering point of the invention is preferably located in the first telephone exchange. The signalling used in the telecommunication network may be ISUP2 signalling (ISUP2, ISDN user part, version 2 ) . The invention also relates to a system for the processing of charge messages in a telecommunication system as described above. In the system of the invention, the originating side of the second telephone exchange comprises means for checking a charge message sent by the terminating side and means for combining the charge data sent by the originating side to the registering point and the charge data received from the terminating side if the charge data sent by the terminating side bear similarities to the charge data sent from the originating side to the registering point. Moreover, the system of the invention comprises means for modifying the charge data so as to form a replacing charge message containing combined charge data and means for sending a replacing charge message to the registering point. In a preferred embodiment of the invention, the originating side of the second telephone exchange comprises means for summing the tariff data sent to the registering point and the tariff data received from the terminating side when the tariff categories in the charge messages are the same. Moreover, the originating side of the second telephone exchange preferably comprises means for generating an acknowledgement message and sending it to the terminating side after the registering point has acknowledged the replacing charge message sent to it. In a preferred embodiment of the invention, the originating side of the second telephone exchange comprises means for combining all charge messages received from the terminating side if the charge data bear similarities to the charge data sent to the registering point. The registering point of the invention is preferably located in the first telephone exchange. The signalling used in the telecommunication network may be ISUP2 signalling. The invention helps achieve a successful telecommunication connection. It prevents the occur- rence of error situations and call setdown if charge messages with the same tariff categories are sent from both the originating and terminating sides of a network element. The invention also allows the introduction of new services using originating and terminating side calculation. LIST OF ILLUSTRATIONS In the following, the invention will be described in detail by the aid of a few examples of its embodiments, wherein Fig. 1 presents an embodiment of the system of the invention, and Fig. 2 presents a functional block diagram of an embodiment as illustrated in Fig. 1. DETAILED DESCRIPTION OF THE INVENTION The system illustrated in Fig. 1 comprises A and B-subscribers ' terminal devices A-DTE, B-DTE and A and B-subscribers ' telephone exchanges AX, BX. In Fig. 1, the registering point RP is located in the A- subscriber's telephone exchange. In the registering point, received CHG messages (Charge messages) are distinguished from each other on the basis of tariff category and signalling point code. Thus, charge data received from different addresses are stored m dif- ferent locations m the registering point. The subscriber is charged on the basis of the information m the registering point. In the B-subscriber ' s telephone exchange, both originating side and terminating side calculation is m use. Therefore, CHG messages are sent from both sides. For the verification of charge data, the originating side comprises means 11. For the summing of tariff data, the originating side comprises means 12. For the modification and transmission of the mes- sage, the originating side comprises means 13, 14. In the case of the present example, these means 11, 12, 13, 14 are implemented in a manner known to the skilled person, e.g. using software, memory and electronics and making small changes m existing technol- ogy. The originating side comprises means 15 for generating and sending a CHGA message of appropriate form. In the case of the example, these means are implemented m a manner known m itself and they will therefore not be described m greater detail . In addition, the system presented m Fig. 1 comprises means 16 for summing all CHG messages received from the terminating side T of the B- subscπber's telephone exchange BX and having the same tariff category and the same signalling point code as m the message sent to the registering point RP . These means are implemented m a manner known to the skilled person. In the telecommunication network m the example, ISUP2 signalling (ISUP2, ISDN user part, version 2) is used. In the embodiment illustrated m Fig. 1, an A-subscriber calls a B-subscriber m an ISDN network m which the charging for the connection is effected on the basis of CHG messages. The events m the example are presented m the block diagram m Fig. 2. The A- subscriber, using his/her telecommunication terminal, calls the B-subscriber . During the call set-up, a CHG message containing charge data is sent from the B-subscriber ' s telephone exchange BX to the registering point RP, block 21. This message is first stored on the originating side, block 21a, and then transmitted from the originating side 0 of the exchange. Storing the message ensures that control of tariffs sent will remain with the originating side. After this, the originating side remains waiting for a CHGA message (CHGA, CHarGe Acknowledgement) from the registering point, block 22. If the originating side receives an affirmative CHGA response, then a telecommunication connection can be set up between the subscribers' terminals, block 23. If no CHGA message is received within a certain length of time or if a negative one is received, then the call set-up procedure will be terminated, block 31. At a later stage of the call, the originating side can generate CHG tariff of the same tariff category as on the terminating side before. In this case, too, it must oe possible to combine the tariffs and send them as a replacing tariff to the originating line. Next, a CHG message is sent from the terminating side T of the B-subscriber ' s telephone exchange BX, which message is also transmitted to the originating side 0, block 24. On the originating side, the message is checked to determine its tariff category, block 25. If the tariff category is the same as m the CHG message sent from the originating side during call set-up, then the message is not sent directly to the registering point RP but is first modified to give it the right form. At this point, the charge data of the received and sent messages are summed together, block 26. In addition, the message is turned into a CHG up- date message and stored on the originating side, block 26a, and this message is sent to the registering point, block 27. If the tariff category differs from the tariff category of the message sent, then the CHG message of the terminating side can be first stored on the originating side, block 25a, and then transmitted further, block 32, because the registering point will distinguish these messages from each other. When the originating side 0 receives a replacing tariff from the terminating side T, a replacing tariff in which only the share of the terminating side tariff has been replaced must be sent to the originating connection. To make this possible, it is necessary for the originating side to separately maintain the originating side's own tariffs and the summed tariff of the originating/terminating side. Thus, in the summed tariff, the replacing tariff received from the terminating side only replaces the share of the terminating side. The registering point RP uses the CHG update message to replace the data of the CHG message received with the same signalling point code and tariff category. In the present example, the registering point thus replaces the old data with new summed tariff data of the originating and terminating sides, block 28. After the required changes have been accomplished, the registering point sends an affirmative CHGA acknowledgement message to the address indicated by the signalling point code, block 29. When the originating side 0 receives this message, it generates a CHGA message and sends it to the terminating side T, block 30. This CHGA message tells the terminating side whether the call set-up procedure can be continued or not. Having received an affirmative CHGA message from the originating side, the terminating side will con- tinue the call set-up procedure in the normal manner. The embodiment described in the example can be used e.g. in a "number transferability" service provided by a telecommunication network operator. The invention is not restricted to the examples of its embodiments described above, but many variations are possible within the scope of the inventive idea defined in the claims

Claims: CLAIMS 1. Method for the processing of charge messages in a telecommunication system comprising a registering point (RP) where received charge messages are distinguished from each other on the basis of tariff category and signalling point code, a first telephone exchange (AX) , to which the calling subscriber is connected, and a second telephone exchange (BX) , to which the called subscriber is connected and which telephone exchange uses charge calculation based on charge messages of both the originating side (0) and the terminating side (T) , a charge message being sent during call set-up from the originating side to the registering point, charac t e r i s ed in that a charge message received from the terminating side (T) is checked on the originating side (0) of the second telephone exchange (BX) ; the charge data of the originating side (0) and of the terminating side (T) are combined if they bear similarities; the charge message is modified to form a replacing charge message that contains the combined charge data; and the replacing charge message is sent to the registering point (RP) . 2. Method as defined in claim 1, char ac t eri sed in that the tariff data sent in the charge message from the originating side (0) to the registering point (RP) and the tariff data sent in the charge message from the terminating side (T) are summed together if the tariff category in these messages is the same, and the sum is sent in the replac- ing charge message to the registering point (RP) . 3. Method as defined in claim 1 or 2, charac t e r i s ed in that an acknowledgement message is sent from the originating side (0) to the terminating side (T,) after the registering point (RP) has acknowledged the replacing charge message sent from originating side. 4. Method as defined m any one of claims 1 - 3, charac t e r i s ed m that all charge messages received by the originating side (0) from the terminating side (T) m which the charge data bear simi- larities to the charge data sent to the registering point (RP) are combined. 5. Method as defined m any one of claims 1 - 4, charac t e ri s ed m that the registering point (RP) is comprised m the first telephone ex- change (AX) . 6. Method as defined m any one of claims 1 - 5, charac t e ri s ed m that ISUP2 signalling is used m the telecommunication network. 7. System for the processing of charge es- sages m a telecommunication system comprising a registering point (RP) where received charge messages are distinguished from each other on the basis of tariff category and signalling point code, a first telephone exchange (AX) , to which the calling subscriber is con- nected, and a second telephone exchange (BX) , to which the called subscriber is connected and which telephone exchange uses charge calculation based on charge messages of both the originating side (0) and the terminating side (T) , a charge message being sent during call set-up from the originating side to the registering point, charact eri sed m that the originating side (0) of the second telephone exchange (BX) comprises means (11) for checking a charge message received from the terminating side (T) ; means (12) for combining the charge data sent by the originating side (O) to the registering point (RP) and the charge data received from terminating side (T) if the charge data sent by the terminating side (T) bear similarities to the charge data sent from the originating side (0) to the registering point (RP) ; means (13) for modifying the charge message so as to form a replacing charge message containing the combined charge data; and means (14) for sending the replacing charge message to the registering point (RP) . 8. System as defined in claim 7, char ac t e ri s ed in that the originating side (0) of the second telephone exchange (BX) comprises means (12) for summing the tariff data sent by the originating side (0) to the registering point (RP) and the tariff data received from the terminating side (T) together when the tariff categories in the charge mes- sages are the same. 9. System as defined in claim 7 or 8, charac t e ri s ed in that the originating side (0) of the second telephone exchange (BX) comprises means (15) for generating an acknowledgement message and sending it to the terminating side (T) after the registering point (RP) has acknowledged the replacing charge message sent from the originating side. 10. System as defined in any one of claims 7 - 9 , charac t eri s ed in that the originating side (0) of the second telephone exchange (BX) comprises means (16) for combining all charge messages received from the terminating side (T) in which the charge data bear similarities to the charge data sent to the registering point (RP) . 11. System as defined in any one of claims 7 - 10, charac t e ri s ed in that the registering point is comprised in the first telephone exchange (AX) . 12. System as defined in any one of claims 7 - 11, charac t eri s ed in that ISUP2 signalling is used in the telecommunication network.

Inventors: SALONEN TIMO JUHANI, SIMONEN ARI-PEKKA, SALONEN, TIMO, JUHANI, SIMONEN, ARI-PEKKA
Applicants: NOKIA NETWORKS OY, SALONEN TIMO JUHANI, SIMONEN ARI PEKKA, SALONEN, TIMO, JUHANI, SIMONEN, ARI-PEKKA
Application year: 1999
Main classification: H04M15
IPC codes: H04L12, H04M15