METHOD AND SYSTEM FOR PROVIDING AT LEAST ONE SUBSCRIBER SERVICE IN A COMMUNICATION SYSTEM COMPRISING AT LEAST TWO NETWORKS

Abstract: The present invention provides a method and system for providing supplementary services for a subscriber roaming from a first to a second network. The second network receives information on supplementary services during home location updating, and emulates the subscriber services. Therefore, the roaming subscriber is provided with the same supplementary services irrespective of roaming to another network.

Description: WO 01/76296 ~ λ ~ PCT/EP00/02982 METHOD AND SYSTEM FOR PROVIDING AT LEAST ONE SUBSCRIBER SERVICE IN A COMMUNICATION SYSTEM COMPRISING AT LEAST TWO NETWORKS FIELD OF THE INVENTION The present invention relates to a method and system for providing (implementing) at least one subscriber service in a communication system comprising at least two networks. The invention is particularly related to the handling of subscriber-defined services when roaming from the home communication network to another communication network. BACKGROUND OF THE INVENTION In a mobile communication network such as a GS -based network, it is customary to provide some subscriber- selectable services such as forwarding a call to a different terminating number either in every case or only when the called subscriber equipment is busy, for instance. A further example is the barring of outgoing calls, for instance of every outgoing call or only of outgoing international calls. The necessary information for handling a desired subscriber service may be stored in a register containing further subscriber-specific data. In a GSM telecommunication system, this register may be the home location register (HLR) or any other storage. The basic structure and function of such networks is standardised, see for instance GSM Technical Specification GSM 02.78 which is issued by ETSI (European Telecommunications Standards Institute) . This specification furthermore specifies the service definition of a CAMEL architecture (Customised Applications for Mobile network Enhanced Logic) . This subscriber information register may be accessed by the user equipment when information on the handling of specific events are necessary. When the subscriber is roaming in a second network different from his/her home network, the subscriber services indicated in the subscriber's services profile must be executed in this second network In normal case the home network and the second network are based on similar technology (like GSM technology) and they support similar standardized execution semantics for the services indicated. Thus, the user observes similar service experience in both networks. A problem arises if the second network does not support exactly similar service standards or the interpretation for a given service identified m the subscriber's services profile is missing in the second network. SUMMARY OF THE INVENTION The present invention aims at providing a method and system for providing a subscriber-defined service even when attaching to another network, without unduly increasing the data flow between the networks. According to one aspect, the present invention provides a method for activating at least one subscriber service in at least one communication system comprising, or using, at least a first and a second network, the first network having a register storing information on the at least one subscriber service. When an equipment is attaching to the second network, a control device of the second network accesses the first network for obtaining information on a (or more) presently activated subscriber service, and activates a control function for emulating the presently selected or activated subscriber service in the second network. The invention furthermore provides a system as defined in the independent system claim, m particular for carrying-out the above-defined method. According to the present invention, when a (or more) subscriber service is activated for a subscriber equipment which is attaching to a second network, the necessary information on the selected subscriber service is obtained, by the second network, from the first network, and is emulated in the second network. Therefore, the subscriber (or subscriber equipment) attaching to the second network, for instance because of a roaming subscriber, will be provided with the same service as the one selected in the home network. This is of benefit for the suoscriber as same will continue to receive the same service (s) without any necessity of specific operations by the subscriber. Furthermore, the second network has to access the first network only once for obtaining the information on the selected subscriber service (s). This access can even be performed in combination with the necessary location update of the register of the home network storing the location information on the respective subscriber. Thereafter, the second network will provide the same (or at least essentially the same) service as the one to which the subscriber is presently accustomed, without necessity of once again accessing the first network. This solution furthermore reduces the overall signalling and data traffic between the two networks, and avoids any time delays possibly caused by such frequent information transmission between two networks. BRIEF DESCRIPTION OF THE FIGURES Fig. 1 shows a schematical outline of a communication system comprising two different communication networks; Fig. 2 illustrates a block diagram of one embodiment of the invention; and Fig. 3 shows a flow chart of an embodiment of a method according to the present invention. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE PRESENT INVENTION Fig. 1 shows a communication system adapted to implement the present invention. The communication system comprises at least two networks, in particular telecommunication networks (mobile communication or circuit-switched networks for transmitting voice, data and/or other information). According to the example shown in Fig. 1, the communication system comprises a UMTS (Universal Mobile Telecommunications System) network 1 and an IP (Internet Protocol) network 6. These networks are only examples and may also be of a different type such as circuit-switched networks, GSM (Global Standard for Mobile Communication) or any other type, and may be networks based on identical standards or may be based, as shown in Fig. 1, on different standards (UMTS network 1 and all-IP-based network 6). The network 1 comprises several base stations 2 which may be mobile or fixed stations, and at least one home location register (HLR) 3. The home location register 3 stores information on registered subscribers including identification information such as IMSI (International Mobile Subscriber Identity), MSISDN (Phone Number), and information on supplementary services activated for subscribers such as an automatic incoming call forwarding to another number, or barring of outgoing calls. These supplementary services may be specified by the subscriber or other persons or companies. Fiq. 1 illustrates a case in which a mobile station (MS) 4 having its home location in communication network 1 is roaming and attaching to the communication network 6. This communication network 6 comprises one or more elements (SSS) 5 for providing supplementary services to the user of the mobile station 4 similar to same registered in the home location register 3. The device 5 is, in the present embodiment, a serving subscriber system SSS (Serving Subscriber System) which also serves as a visitor location register (VLL) for storing information on visiting users. The structure and functioning of home location registers and visitor location registers is known to the man skilled m the art and will, therefore, not be described in greater detail. Fig. 2 shows a block diagram illustrating an embodiment of the telecommunication system according to the present invention. As shown in Fig. 2, the system comprises a support node 7 which forms part of the network 1 and serves as a gateway node for communicating with a support node 8 of the network 6. This support node 8 may likewise be a gateway support node for inter-network communication. The borderline between the two networks 1 and 6 is indicated by means of the vertical broken line between the support nodes 7 and 8. The support node 7 communicates with the home location register 3 for reading-out subscriber information stored therein. The support node 8 of network 6 communicates with a visitor location register (VLL) 9 of network 6 which temporarily stores information on visiting users such as roaming subscribers as illustrated by mobile station 4 (Fig. 1) . The serving subscriber system 5 communicates with the visitor location register 9 and a network element (CSE) 10 which serves for implementing logic programs emulating the subscriber service (s) stored in home location register 3, for roaming subscribers. WO 01/76296 " b M PCT/EP00/02982 The basic idea of the present invention is to provide supplementary service transparency to subscribers roaming from one network into another network. For instance, the supplementary service stored in one network, here the network 1 is offered to roaming subscribers by using a supplementary service emulation. For instance, the network 1 may be a GSM network in accordance with the Release 99 specification whereas the network 6 may be a network as defined in the Release 2000, for instance a network according to ALL-IP- option of Release 2000. The supplementary service emulation is then preferably performed using CAMEL (customised application for mobile network enhanced logic) . Generally, when a subscriber is roaming from network 1 to network 6 and is attaching to network 6, the subscriber data stored in home location register 3 is read-out therefrom and is inserted into the serving subscriber system 5, i.e. into visitor location register 9 of network 6. These subscriber data include the supplementary services presently activated for the subscriber. The serving subscriber system 5 is analysing these supplementary services which are stored for the newly attached roaming subscriber 4 in the visitor location register 9. The serving subscriber system 5 then forms trigger data for the roaming subscriber to point to the CAMEL services emulating the supplementary services indicated in the subscriber data. Instead of using CAMEL services, the supplementary services standardised for GSM, as well as the other services, may also be implemented (emulated) using other service creation tool kits such as MExE or SAT, or may be implemented by using and/or designing specific control programs. The advantage of implementing the same supplementary services as the ones defined in the home network is that the subscribers roaming into a different network receives the same services in all visited networks. The services include WO 01/76296 ~ ~ ' " PCT/EP00/02982 standardised supplementary services (SS) that are standardised for the serving network and are therefore well defined and can be emulated in the visiting networks using pre-definable tools. Fig. 3 shows the basic steps of an embodiment of the method according to the present invention. When a subscriber carrying a user equipment such as mobile station 4, is roaming and entering the area of network 6, the user equipment is attaching to this network 6, step SI. Then, a location update procedure is performed with regard to the home location register 3 of network 1 to which the user was previously attached (first part of step S2) . As a result of the location update, the home location register 3 is returning the service profile information such as the supplementary services (SS) stored in the home location register 3 for the respective user which service profile information is transmitted to the network 6 (second part of step S2) . The serving subscriber system 5 of network 6 analyses the service profile information, for instance using a pre-defined algorithm to recognise the supplementary service(s); step S3. Furthermore, the serving subscriber system 5 controls the emulation of the service profile, step S4, for instance by setting-up programs implementing the functions of the service profile, i.e. the supplementary services. For implementing the service profile, the tool kits available in the serving network 6 are used. In the following, an example will be described. For instance, the following service profile (supplementary services) is activated for the subscriber: - call forward on busy (CFB) to number 123456; - barring of all outgoing international non-HPLMN calls (BOIC-exHC) active (all outgoing international calls are blocked unless directed to the home network 3 (HPLMN, home public land mobile network). The network 6 is implementing (emulating) this supplementary service profile by using, for instance, CAMEL. The serving subscriber system prepares the ability to trigger service logic programs (SLP) for implementing the functionality of the supplementary services, for instance into CAMEL service environment (CSE) , and arms relevant triggers in the BCSMs (Basic Call State Models) . For basic details with regard to CAMEL, CSE, and the function thereof, it is referred to the relevant standards such as GSM02.78, published by ETSI (European Telecommunications Stanαards Institute) . The service logic programs (SLPs) may be located in distict service control elements (SCE) . During the analysis of activated supplementary services, the control device such as SSS 5 will determine the address of an appropriate SCE based on a database mapping the supplementary services to the SCEs implementing these services. The SLPs may have been written and installed m the control function in advance. The SSS has been provided with information on the control function addresses and service logic program identities, I. e. address or port within the control function for each known supplementary service. For example, an SLP emulating a call forwarding service may consist of a means or function to fill m the forwarded-to number to the connect message to the CSCF/MSC. The supplementary services may be realised using, for instance, the following configuration: - Trigger from T-BCSM DP13 (T_Busy; Terminating Basic Call State Model Detection Point 13) to service logic program SLP that forwards the call to the number 123456; - Trigger from O-BCSM DP2 (Collected_Info; Originating Base Call State Model Detection Point 2) to SLP that analyses the called number and screens out all international calls not going to the home network of the subscriber. The service logic programs may be installed in the CAMEL service environments CSEs when deploying the supplementary services support. Then, when effecting the analysis of activated supplementary services, the visitor network 6 will select the appropriate service logic program providing (emulating) an activated supplementary service. Thus, the subscriber service system (SSS) 5 forms the trigger data for the roaming subscriber which point to the CAMEL services emulating the supplementary services mentioned in the subscriber data read-out of the home location register 3. According to the invention, an analysis of the standard supplementary services profile is performed, and these supplementary services are emulated m the visiting network. When a set of CAMEL services already exists in the trigger data, the subscriber service system (SSS) 5 may notify the CSE 10 at the subscriber data insertion (read-out from the HLR 3) and at the analysis of the standard supplementary services profile, for additionally implementing the supplementary services. There may be parameters associated with the services in the subscriber data of the HLR. For instance, call forwarding service is accompanied with forwarded-to numbers and conditions . hen subscriber service data is inserted to the second network, the control function of the second network is contacted to upload the parameters accompanying the standardised services to the control function. When e.g. the call forwarding service is implemented by triggering at the visited CSCF/MSC terminating basic call state model detection point T_Busy, the forwarding service is triggered at this detection point. The control function now knows the forwarded-to number because it has been uploaded there together with other service parameteres e.g. at subscriber data insertion. If the control function resides in the visited, i.e. the second network, the interaction of the services emulating the supplementary services and the intelligent network services of the home network control function may become a problem. E.g. a prepaid service triggered to the home network control function from detection point 0_Collected_Info may block the triggering of the call barring emulation service which is maybe triggered from the same detection point. A solution is that a different set of detection points parallel to the normal basic call state model detection points, which are used to trigger services from the home network control function, is defined. If there is a controlling service triggered from these normal basic call state model detection points, then that service does not prevent the triggering from the second set of detection points . The detection points of the second set of detection points can be defined in association with the normal detection points of the basic call state model, but they are treated separately in the service switching function, which is the interface between the control function and the basic call state model of the CSCF/MSC. The separate treatment means e.g. that the single point of control rule of intelligent network allowing only one control relationship with the control function does not apply to the second set of detection points. T^e benefit of the second set of detection points is that it is emulating quite closely the behaviour of the standardised supplementary service execution within a GSM/UMTS release 99 compliant switch call state model functionality. Although the invention has been described above by referring to preferred embodiments, the invention is not restricted to the details thereof and also covers any changes, modifications, amendments or alternatives.

Claims: CLAI MS 1. Method for providing at least one subscriber service in at least one communication system comprising at least a first and a second network, the first network having a register storing information on the at least one subscriber service, wherein a control device of the second network accesses the first network for obtaining information on at least one subscriber service, and prepares readiness m the second network to use a control function for the emulation of the at least one subscriber service. 2. Method according to claim 1, wherein the control device of the second network accesses the first network for obtaining the information on the at least one subscriber service when a subscriber equipment is attaching to the second network. 3. Method according to claim 1 or 2, wherein the second network is an IP-based network, preferably an IP-based mobile telephony network. 4. Method according to claim 1, 2 or 3, wherein the control device of the second network is part of an Intelligent Network. 5. Method according to claim 4, wherein the control device is CAMEL-based. 6. Method according to any one of the preceding claims, wnerein a set of detection points for invoking at least one of the emulated subscriber services at the occurrence of one of these detection points during handling of a call is defined in the second network. 7. Method according to claim 6, wherein the set of detection points for invoking at least one of the emulated subscriber services is defined in the second network in addition to detection points used for triggering other services from a service control function of the first network at the occurrence of one of these detection points during handling of a call. 8. System for providing at least one subscriber service in at least one communication system comprising at least a first and a second network, the first network having a register storing information on the at least one subscriber service, wherein the second network comprises a control device which is adapted to access the first network for obtaining information on a subscriber service, and is adapted to prepare readiness in the second network to use a control function for emulating the subscriber service. 9. System according to claim 8, wherein the control device of the second network is adapted to access the first network for obtaining the information on the at least one subscriber service when a subscriber equipment is attaching to the second network. 10. System according to claim 8 or 9, wherein the second network is an IP-based network, preferably an IP-based mobile telephony network. 11. System according to claim 8, 9, or 10, wherein the control device of the second network is part of an Intelligent Network. 12. System according to claim 11, wherein the control device is CAMEL-based. 13. System according to any one of the preceding claims 8 to 12, wherein a set of detection points for invoking at least one of the emulated subscriber services at the occurrence of one of these detection points during handling of a call is defined in the second network. 14. System according to claim 13, wherein the set of detection points for invoking at least one of the emulated subscriber services is defined in the second network in addition to detection points used for triggering other services from a service control function of the first network at the occurrence of one of these detection points during handling of a call.

Inventors: OJALA ERKKI, PAETTIKANGAS ESKO, SYRJAELAE JARI, USKELA SAMI, OJALA, ERKKI, PAETTIKANGAS, ESKO, SYRJAELAE, JARI, USKELA, SAMI
Applicants: NOKIA NETWORKS OY, OJALA ERKKI, PAETTIKANGAS ESKO, SYRJAELAE JARI, USKELA SAMI, OJALA, ERKKI, PAETTIKANGAS, ESKO, SYRJAELAE, JARI, USKELA, SAMI
Application year: 2000
Main classification: H04Q7
IPC codes: H04Q3, H04W8