The present invention relates to a method for updating a list of identification numbers, such as subscriber numbers, which are stored in memory means of a communication device, the communication device being arranged to communicate with a plurality of communication networks. In a further aspect, the present invention relates to a communication device for communicating with a plurality of communication networks, the communication device comprising processing means and memory means connectable to the processing means.

Such a method and system are known from European patent application EP-A- 1. 158. 825. In this document, a method and a communication device are described, enabling a user to dial a subscriber number with a usual format, e. g. stored in a phone book file. The subscriber number is intercepted after dialing by an application running on the communication device, a mobile telephone. After interception, the application adds a prefix at real-time and dials the converted number. This method offers seamless usage to the user, e. g. when roaming in a network of a different provider it is possible to use the normal phone book as stored on the mobile telephone. However, it requires specific capabilities of the mobile device, such as'Call Control'which enables the application to intercept outgoing phone calls.

Applications for mobile network operators, with a focus on mobile device based applications on Subscriber Identity Module (SIM) cards, in handsets or Personal Digital Assistants (PDA's) are becoming widely available. One of the area's that is often addressed in these type of applications, is the conversion of telephone numbers to another format for usage with additional services. When considering the objective; simplifying the usage of these services by preventing the user from having to remember and to key in complicated codes, several alternative methods are possible to offer seamless functionality.

It is an objective of the present invention to provide a method for converting identification numbers stored in a communication device, which operates as invisible to a user as possible, and which can be used in present communication devices with minimal additional requirements on hardware capabilities.

Therefore, the present invention relates to a method of the type as defined in the preamble above, in which the method comprises the steps of retrieving the

identification numbers of the stored list of identification numbers from the memory means, modifying the identification numbers according to a predefined set of conversion rules, and storing the list of modified identification numbers in the memory means.

In this way, the identification numbers codes are always in the correct format, and ready to use for establishing a connection. The method according to the invention is much less depending on hardware capabilities than the known method, and can be used on a vast majority of phones currently in the market. The present method is particularly suited for mobile communication networks that offer special network services accessible via special dialling codes, e. g. roaming on communication networks which are not operated by the user's own service provider. The method can work virtually unnoticeable to the user.

In a further embodiment of the present invention, the step of modifying the list of identification numbers is executed after detection of a predetermined event. The predetermined event is e. g. a change of communication network. Using this embodiment, the user of a mobile telephone can use his phone book (list of identification numbers) in every communication network without any further actions required. The method can also be executed, at any time, on initiative of the user e. g. via the menu of the communications device.

The predetermined event may also be a combination of a power-up of the communication device and the detection of a difference of the current communication network and the previous communication network. This may e. g. be monitored by storing a communication network in memory.

Alternatively, the predetermined event may be an initiation by a user of the communication device. In an embodiment, the step of modifying is executed only after prompting a user of the communication device. Prompting may be realised via a menu on a screen of the communication device.

The predetermined event may also be an initiation by a network operator; e. g. it may be a command from a communication network using USSD, SMS and/or Over- The-Air signaling (OTA).

In a further embodiment, the predefined set of conversion rules comprise the addition of a prefix sequence of characters and/or a suffix sequence of characters to an identification number in the list, the prefix and/or suffix sequence being dependent on

the communication network with which the communication device is in contact. This may be especially advantageous when the service provider e. g. provides a call back or carrier select functionality for its subscribers, as the usage of this functionality usually requires selection of additional symbols or numbers by the user. When returning to its home network, the prefix and/or suffix sequence may be blanks, thus effectively reversing the conversion of the list of identification numbers.

Also, in a further embodiment, the predefined set of conversion rules further comprise the modification of the identification number. E. g. when a conversion is necessary from a national subscriber number to an international subscriber number, it is usually required to delete the first zero of the subscriber number and to add the country code (e. g.: 020 1234567 >> +3120 1234567).

The prefix and/or suffix sequence and the identification number may in a further embodiment form a USSD message. Such a USSD message may be transferred automatically to a home network provider exchange when received in a communication network when roaming.

In a further aspect, the present invention also relates to a communication device for communicating with a plurality of communication networks, the communication device comprising processing means and memory means, such as a SIM card, connectable to the processing means, in which the processing means are arranged to execute the steps of the present method.

Also, the present invention relates to a software program, which, when loaded on a communication device for communicating with a plurality of communication networks, provides the communication device with the functionality of the present method, and to a SIM card or a data carrier provided with such a software program.

The present invention will now be explained in further detail using an exemplary embodiment of the invention, with reference to the accompanying drawings, in which Fig. 1 shows a schematic diagram of a communication device; Fig. 2 shows a schematic diagram of a SIM card.

Fig. 3 shows a schematic representation of a conversion module according to an embodiment of the present invention; Fig. 4 shows a representation of two possible formats of phonebook entries;

Fig. 5 shows a schematic representation of a conversion recommendation module as used in an embodiment of the present invention; Fig. 6 and 7 show flow charts of a conversion procedure according to an embodiment of the invention.

In this embodiment the method is executed by a phonebook application, which may be loaded on a SIM card in a mobile telephone. Figure 1 shows a schematic diagram of a communication device 1, which will be referred to as mobile telephone 1.

The mobile telephone 1 comprises a processor 2, a SIM card 3, a memory 4, a radio transmitter and receiver 5 and an antenna 6. The SIM card 3 is used to provide user-specific data and algorithms, and data specific for the network providing a mobile telephone service.

Fig. 2 shows a schematic diagram of the SIM card 3 in more detail. The SIM card 3 comprises an interface 11, a SIM processor 12, a RAM memory 13, an EEPROM memory 10 and a ROM memory 14. In the EEPROM memory 10, or in the memory 4 of the mobile telephone 1, data is stored for establishing a connection. This data may comprise entries of a phone book or software for the functioning of the mobile telephone 1.

According to the invention, the data also comprises a new phonebook application.

The phonebook application offers the functionality to convert telephone numbers stored on a mobile device, to different formats. In an embodiment, the application consists of two major functional modules: - a conversion module (CM) that does the actual conversion of phonebook entries, - a conversion recommendation module (CRM) that determines when conversion is applicable.

Figure 3 shows a schematic representation of the conversion module 15. A first phonebook 16 in state A is inputted into the conversion module 15. Also a set of predetermined conversion rules 17, and application parameters 18 are input for the conversion module 15. The application parameters 18 comprise specific operator and subscriber information. The conversion module 15 outputs a second phonebook 19, which entries are in state B. The conversion module 15 converts a phonebook in a state A 16 into a phonebook in a state B 19 based on the set of predetermined conversion rules 17 and the application parameters 18 specific for A->B conversion.

Figure 4 shows an example of two formats of the phonebook entries. In state A, a phonebook entry constitutes an (optional) international code followed by a national telephone number, as indicated by reference numeral 20. Format A is the'normal' format used in prior art devices. In state B, a phonebook entry constitutes an optional prefix code, followed by an (optional) international code, followed by a national telephone number, followed by an optional suffix, as indicated by reference numeral 21. The prefix and suffix may contain any characters, such as numbers like 0... 9, or letters like a... z, but also other characters which are used in present USSD messages, like for example'#'and'*'. The allowed characters are only limited by the specific implementation, the used device and/or communication protocol.

When format B is no longer applicable, the application according to one embodiment of the invention performs the reverse process, i. e. the conversion from state B back to state A. This is indicated by the arrows in figure 4.

Figure 5 shows a schematic representation of a conversion recommendation module (CRM) 31. The CRM 31 has several inputs. The first is a current phonebook state 32, (i. e. 'A'or'B'). A second input is a network and country code 33 of a current physical location of the mobile telephone. A third input is a network and country code of a last known (i. e. stored) location 34. Yet another input is a status 35 which indicates if any phonebook entry has been changed. The CRM 31 outputs information 36 about a possible conversion or update of the phonebook. The CRM 31 uses the country codes and network codes of the current, 33, and last known, 34, physical location of the mobile telephone, and the status 35 and the current phonebook state 32 to recommend or initiate a conversion. The difference between a recommendation and an initiation is that at a recommendation, the CRM 31 triggers the CM 15, only after asking a user whether a conversion is required, where an initiation directly triggers the CM 15. The user can also manually initiate the CM 15 (e. g. via a menu item). In another embodiment, the CRM 31 also recommends or initiates an update procedure, which converts only part of a phonebook. E. g. when a user enters new numbers that are not compliant with the current state.

Figure 6 shows a flow chart outlining the procedure executed by the CRM 31 and the CM 15. The procedure may be triggered by a predetermined event, like for example a power-up of the mobile telephone, or by a location change of the mobile telephone.

After the start of the procedure, indicated by reference numeral 401, an exception table

is checked in step 402. In this exception table, several combinations of Mobile Country Codes (MCC) and Mobile Network Codes (MNC) are stored. MNC/MCC combinations stored in this table represent networks where the phonebook should be converted to a specific state (or should not be converted to a state, depending on the implementation). If the current MNC/MCC is an exception, the procedure ends, see step 404. If the current MNC/MCC is not an exception, step 406 follows, in which is tested whether the new location type (NLT), i. e. 'A'or'B', equals the last known location type (LKLT). If the NLT does not equal the LKLT, step 408 follows, where the NLT is compared to the current phonebook state (PBS). The current phonebook state PBS may e. g. be stored in a register in one of the memories 4,10, 14. If the NLT is not equal to the PBS, step 410 follows. The operator may choose to have the application automatically convert the phonebook, without user interaction, when a relevant location change is detected. If this is the case, step 412 follows in which the conversion is started (by the CM 1). If the operator chooses to let the user interact, no automatic conversion is executed, but step 416 follows in which a suggestion to the user is made, for a conversion. If the user wants to convert, see step 418, step 412 follows. If the user does not want to convert, step 414 follows. At step 414, the LKLT becomes equal to the NLT. After step 412, in which the conversion is started, step 414 follows. After step 414, the procedure ends at step 416.

If, at step 406, the NLT equals the LKLT, step 418 follows, where the NLT is compared to the current phonebook state (PBS). If this is not the case, the procedure ends at step 404. If however, NLT equals the PBS, then the next step is step 420 where the PBS is checked. When at step 408, the NLT is equal to the PBS, step 422 follows, where the LKLT becomes the NLT. Then step 420 is executed. If at step 420, PBS is 'A', then the procedure ends at step 404. The application will now remain in an idle state, and wait for a next trigger to start again. If PBS is'B'then the procedure proceeds with step 426 shown in figure 7. In step 426, it is tested if the initiating event was a power-up. If this is the case then step 430 follows. If this was not the case, step 428 follows where the procedure ends. The test at step 426 is executed because an update of phone book takes time, and must not be done too frequently.

At step 430, it is checked whether there are any records (i. e. entries) in the phonebook that are not in the B-state. If all records comply with the B-state, the procedure ends at step 428. If there are any records not in the B-state, step 432 follows,

in which the user is suggested to update the phonebook. If the user indicates that an update is required, see step 434, the records are updated in step 436. If no update is required, the procedure ends at step 428. After updating the records at step 436, the procedure ends at step 438.

The invention may be used to offer simple usage of existing USSD Callback services. USSD Callback is a service to enable prepaid customers to call when roaming foreign networks. To use this service, a proprietary dialling sequence (in the form of a USSD message) must be sent as a message, instead of calling the destination number.

The USSD message triggers the operator backend and the user receives a callback from the home network, after which he is connected to the number he wants to call. To sent the USSD message the user must enter :"*<node-number>*<telephone-number>#"and press the send button.

Using the invention, the entries in the phonebook can be converted to USSD messages automatically, when the user switches on the device in a foreign network.

This way, the user can simply call an entry in the phonebook, without worrying about format and codes. In certain cases, the phonebook converter is also used to complement existing SIM Controlled Calling USSD Callback application. This is done by using the invention for phones that do not support the'Call control'functionality needed to use the method where the telephone application intercepts a dialled number, as was described in the preamble.

The invention can also be used for postpaid customers who want to convert national numbers into the international format, needed for calling on roaming networks.

Furthermore, the invention can also be used to add a prefix carrier code in front of telephone numbers to enable"carrier pre select"in networks where this service is available.

While the invention has been described in connection with a preferred embodiment, it will be understood that modifications thereof within the principles outlined above will be evident to those skilled in the art. For example, the communication network, next to GSM, may well be a wireless local area network (WLAN) or a UMTS network. Each communication device will then comprise an application for setting up communication connections, wherein identification codes, representing other communication devices, can be converted prior to the actual communication. When roaming in the network, (or between different networks) the application in a communication device (e. g. a notebook) will modify identification codes to a proper format, with or without interaction of a user.