Patent Publication Number: US-2005118998-A1

Title: System for detecting and storing mobile terminals that access a foreign telephone network

Description:
OBJECT OF THE INVENTION  
      As expressed in the title of this specification, the present invention consists of a detection and storage system of mobile terminals accessing a foreign telephone network, and whose object is to permit providing specific services to those subscribers who are outside of their network, therefore each time a mobile terminal is registered in a foreign network, the terminal data are stored in a data base of the subscriber&#39;s mobile telephone network, such that it is known what subscribers are in a foreign network, in order to provide them with specific services in said foreign network.  
     BACKGROUND OF THE INVENTION  
      Currently, many mobile network subscribers travel from one country to another, causing the terminal to change to one of the networks of the country the subscriber is in. To avoid this drawback, Roaming (international mobile connection) technology has been developed by means of which a mobile network can detect subscribers located in other networks, such that the mobile terminal subscriber is permitted to use the terminal in a mobile network that is outside of coverage of the network to which the subscriber belongs, being able to thus make and receive calls or send and receive short messages. To do so, different mobile telephone networks from different countries are interconnected by means of gateways through which communication with the mobile terminal accessing a foreign network is permitted, therefore the gateway, among other signalings, indicates when a subscriber enters/exits a foreign network, the foreign network data and the data referring to the mobile terminal, all this to activate an indication in the mobile terminal network that said mobile terminal is in a foreign network.  
      In this sense, it is worth mentioning that there is a Roaming Out technology which is the case in which a mobile terminal is in a foreign network and wants to connect to its own. This same case seen from the foreign network is Roaming In, since in this case a foreign terminal accesses the network to communicate with a foreign network.  
      Currently, to provide different specific services to those subscribers who are outside of their network, services such as adapting the subscriber profile (subscriber contracted services) to the features of the network which the subscriber is in for optimizing services the subscriber has contracted with his/her network, has the drawback that it is necessary to know which terminals are outside of their own network and when the entrance and exit of these terminals in their network occurs in order to know which subscriber should be offered these services.  
     DESCRIPTION OF THE INVENTION  
      To know which subscribers should be provided with the specific services when located outside of their network, the invention has developed a new system in which, between the gateway and the mobile terminal network, processing means have been provided which detect, out of all the information circulating through the gateway, the entrance/exit signaling parameters of a terminal in a foreign network, the foreign network data and the data referring to the terminal, such that these data are separated from the remaining data and are sent to analysis means which, after analyzing the information, access storage means which store the terminals which enter/exit a foreign network, the foreign network data and the data of the terminals in a foreign network, to know which terminals and which network each terminal is in, and to thus be able to provide the contracted services in the foreign network.  
      The analysis means are connected to a real time service module which is informed every time an entrance/exit of a terminal in a foreign network is detected, for immediately providing services to the terminals in a foreign network, such that the real time services act in the moment when the subscriber changes network (enters in a foreign network or returns to its own network), all this such that it is not necessary to consult the data base, thus preventing making prior consultations for providing real time services, which significantly simplifies this functionality.  
      This structure prevents the different systems which provide real time services from consulting tables and only becoming operative when information of the subscriber entering/exiting the network which he/she is in at that time reaches the system of the invention.  
      With this solution, the location analyzer also acts when the terminal returns to its network, since, if it corresponds to a change to another foreign network, this has already been notified with the new network location update.  
      The invention foresees that when the analysis means detect the entrance of a terminal into a foreign network, then they consider that the subscriber has entered into said foreign network, storing this information in the data base such that the current subscriber location is updated, and at the same time communicate this to the real time service module so that it may act accordingly.  
      On the contrary, when the analysis means detect the exit of a terminal from a foreign network, then they verify whether they have received notification that the terminal has entered into another foreign network, and in the affirmative case, they consider the subscriber to have entered into said foreign network, storing this information and updating the current subscriber location in the data base, and at the same time communicate this to the real time service module, which acts accordingly; whereas if the verification is negative, then they consult their own network to verify whether the terminal has entered into their network again, and if an affirmative response is obtained, they eliminate the corresponding entry in the data base and report this to the real time service module.  
      The system of the invention also comprises an event-based service module which is connected to an event generator so that when the latter generates a service for subscribers, the event-based service module accesses the data base to know which subscribers are located in foreign networks and to thus be able to provide them with the service.  
      In either case, to permit the described functionality, it is necessary to store in the data base the data referring to the features of each foreign network so as to be able to determine which network the different data received belong to and to adjust the subscriber contracted services to the features of the foreign network, such that the contracted services are optimized according to the features of the foreign network in which the mobile terminal is in.  
      Furthermore, the data base stores the log of all visits made by each terminal to foreign networks to permit consultation thereof by other systems for carrying out statistics, etc. The system comprises the possibility of cleaning the data stored in the log to periodically eliminate all unnecessary information.  
      To help to better understand this specification and forming an integral part thereof, a single drawing is attached below which, with an illustrative and non-limiting character, shows the object of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       FIG. 1  shows a functional block diagram of a possible embodiment example of the system of the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
      A description of the invention is made below based on the aforementioned figure.  
      Currently, many mobile network subscribers travel from one country to another, which causes the subscriber to change to one of the networks of the country he/she is in. To prevent this, Roaming technology was developed with which a mobile network can detect mobile terminals in other networks, such that a mobile terminal subscriber is permitted to use the terminal in a mobile network outside of the coverage of the network to which he/she belongs, thus being able to make and receive calls or to send and receive short messages (SMS) from a network other than the one to which it belongs.  
      By means of the Roaming (international mobile connection) service, it is possible to provide specific services to those subscribers who are outside of their network, but the drawback is based on knowing which subscribers should be provided with these services, it is therefore necessary to know which mobile terminals are outside of their network, as well as to know when the terminals enter and exit their own network.  
      To do so, the invention has developed a system which permits knowing all these data in real time.  
      As is well known, a mobile telephone network  1  is connected to the different foreign mobile telephone networks  3  by means of gateways  2  for exchanging information between the HLR (Home Location Register) of the network  1  and the VLR (Visitor Location Register) of the foreign network.  
      This exchange of information is carried out by means of a protocol called MAP (Mobile Application Protocol) and different information is exchanged between them, among which the following parameters are worth mentioning: Update Location, Insert Subscriber and Cancel Location. The Update Location parameter is generated every time there is a change of mobile terminal location, and by means of this signaling, the location in which the subscriber is registered is updated in the subscriber profile in the HLR.  
      The subscriber profile not only contains the subscriber location, as mentioned, but rather it also includes the services the subscriber has contracted, such as news services, if fixing of rates is carried out by means of contract or pre-payment, if Roaming is active, etc. These subscriber data are located in the Insert Subscriber information, which come to form part of the visited VLR through the sending of an Insert Subscriber for the VLR to know what are this subscriber&#39;s features.  
      With regard to the Cancel Location information, it is worth mentioning that it is generated in the HLR and sent to the VLR so as to indicate that the subscriber has left the domain of this VLR, since an Update Location has been sent from another VLR to the HLR, and the subscriber information that was sent to it must be eliminated.  
      Therefore, signaling is exchanged between the HLR and the VLR of the different mobile telephone networks, by means of which signaling it is indicated when a subscriber enters/exits a foreign network, as well as the data referring to the mobile terminal which has accessed a foreign network, and the foreign network data are also sent, such that by using this information, a system can be created which is capable of knowing which terminals are outside of their own network.  
      For this, the system of the invention comprises a processor  4  connected between the connection gateway  2  of the foreign network  3  with the network  1 , such that all the information passing through the gateway, passes through the processor  4  which continuously reads the information exchanged between the international gateways  2  and a HLR  5  of the mobile terminal&#39;s own network  1 , such that it selects only the aforementioned MAP protocol parameters, i.e., it carries out filter functions by detecting said information. The processor  4  is connected to a location analyzer  6  which collects the information sent via HTTP (Hyper Text Transfer Protocol) and stores this information in a data base  7  while analyzing it in order to detect the detected location changes and to report said changes to a real time service module  8 , such that the latter knows each entrance/exit of a terminal in a foreign network, such that these terminals can be immediately provided with services to the terminals in a foreign network without having to make prior consultations.  
      Furthermore, the data base  7  is connected to an event-based service module  9  which is connected to an event generator  11 , so that when the latter generates a subscriber service, the event-based service module accesses the data base so as to know which subscribers are located in foreign networks, and to thus provide the service to them.  
      An example of an event-based service can be subscription services, such as news while abroad. This service is carried out every certain time by means of the event generator  11  so that the module  9  consults the data base  7  to see which of those subscribers who have contracted the service are abroad, and to thus be able to send them the news.  
      Modules  8  and  9  can be accessed by other systems  10  for providing real time services by means of systems outside of the network itself, or by the subscriber&#39;s network  1 .  
      When the analyzer  6  receives notification corresponding to the exit of a mobile terminal from a network and has not received notification of the entrance into another network, it consults the HLR to know in which VLR the subscriber is registered in order to check whether he/she has already returned to his/her network, since, if the subscriber has returned to his/her own network, there is no exchange of information between the VLR of the outside networks and its own HLR, there being no dialogue that the information processor  4  can pick up. Therefore, the analyzer  6  must consult the HLR  5  of its own network to see if the subscriber is in a VLR of the network, and to thus confirm the presence of the subscriber in the network, since there is no exchange of information through the gateway  2 .  
      Therefore, apart from storing the information received from the processor, the analyzer  6  also stores, in the data base  7 , the information it obtains from the consultations made to the HLR  5 .  
      It is necessary to indicate that the information processor only reports location updates (Update Location) corresponding to an entrance into a foreign network  3 , disregarding those corresponding to VLRs of the same network as the previous ones, since they correspond to movements within the foreign network  3  itself. In the same manner, it only reports location cancellations (Cancel Location) corresponding to an exit from the foreign network, disregarding those corresponding to the VLRs of the same network as the new VLR where it is located, since they correspond to movements within the same network.  
      Therefore, when the location analyzer receives an Update Location message, it considers that the subscriber has entered into a new foreign network  3  and proceeds as follows:  
      1.—It stores this information in the data base  7 , updating the entry corresponding to the current subscriber location.  
      2.—It notifies the real time service module  8  that a new entry has occurred.  
      In the same manner, when the location analyzer  6  receives a Cancel Location message, it considers the subscriber to have left the foreign network  3  in which the subscriber was in up to that time. In this case, two different situations occur:  
      A) It can happen that a location cancellation notification had been received when a network location update notification was received, in which case it is considered that the subscriber has left the network in which he/she was in up to that time and has entered into another new foreign network.  
      B) If a location cancellation notification has been received but a location update notification in another foreign network has not been received, it is considered that the mobile terminal has left the network it was in up to that time and has again entered into its own network  1 . To confirm whether the subscriber has entered in his/her network, a consultation is made in the HLR  5  to detect in which VLR the subscriber is in. This checking is necessary since the processor  4 , as was already described, does not pick up the VLR location update messages of the subscriber&#39;s own network  1 , since it only checks the international links by means of the information passing through the international gateways  2 .  
      In case B, the location analyzer  6  only acts when the client returns to the network since, if it corresponds to a change to another foreign network, the analyzer has already been notified with the location update in the new network. If it is verified that the subscriber has returned to his/her network, it proceeds in the following manner: 
          The corresponding data base entry is eliminated.     The real time service module  8  is informed of this return.        

      It is also worth mentioning that the data base incorporates a log table containing the networks visited by each client, therefore in the previous case, this log table is also updated.  
      Likewise, said log table is updated with each network change, such that by accessing this table, statistics can be carried out and any type of data of interest for systems outside of the subscriber&#39;s network  1  or for said network  1  can be obtained.  
      The MSISDN (Mobile Station International ISDN Number, which corresponds to the mobile telephone number) is stored in this table log, as well as the country code of the network in which it is located, the network operator identifier in which it is located, the Camel version supported by the network, the IN (Intelligent Network) service identifier, if there is or is not an agreement with the foreign network, and the location update date.  
      Also stored in the data base  7  is all the information necessary for identifying the foreign network VLRs, i.e., all the information necessary for knowing which network each VLR (operator table) belongs to.  
      This table stores the country code, the operator identifier, the numbering range identifying each VLR, the supported version for carrying out real time added services (the intelligent network Camel environment focused on mobile subscribers), and in case of not supporting a Camel version, this parameter will be blank, and it also stores whether there is or not an agreement with said foreign network.  
      Therefore, by means of this stored information, the VLR country code can be determined from the VLR number which comprises the country code plus the range, plus the remaining numbering. An example could be 39 348 4228995, which is received in the notifications of the information processor from which, consulting the data base, the VLR country code is obtained which, in the indicated example, is 39 and corresponds to Italy, as well as the identifier of the network to which it belongs, which in the case of the example is 348 and corresponds to Omnitel. In this manner, the system of the invention knows which foreign network a subscriber is registered in.  
      With regard to the update table of each subscriber&#39;s location, this contains the MSISDN, the country code, the operator identifier, the Camel version supported by the network, the IN service identifier if there is an agreement with the network, if it is pre-payment or not, and the date of the last location update.  
      The information sent by the location analyzer  6  to the real time service module  8  comprises the MSISDN, the country code of the network, the operator identifier, the Camel version supported by the network, and the IN service identifier.  
      When the location analyzer  6  receives notification of a location change, it acts on the data base  7  in the following manner: 
          It consults the operator table to obtain the necessary information regarding the VLR.     If it exists, it copies the entry that the subscriber has in the location update table in the log table.     It updates the subscriber data in the location update table.     If the subscriber does not have an entry in this table since he/she is located in his/her network up to that time, but has entered a foreign network, it creates an entry.     If the subscriber has an entry, since he/she is in a foreign network, but has entered another foreign network, it updates the entry.     If the subscriber returns to his/her network, his/her entry will be eliminated.