Switching connectivity between first and second mobile radio networks

Abstract

A method for switching connectivity between a first mobile radio network and a second mobile radio network in a SIM hosted in a mobile radio communication device, characterized in that: a first ADFUSIM entry and a second ADFUSIM entry are included in the same configuration file; a handover of connectivity from the first mobile radio network to the second mobile radio network is performed by switching the configuration of the configuration file from using the first ADFUSIM entry to using the second ADFUSIM entry.

Description

Technical Field

[0001] The invention relates to a method in a SIM hosted in a mobile radio communication device for switching connectivity between a first mobile radio network and a second mobile radio network. Background Art

[0002] Mobile radio devices are widely known and are used by consumers, in particular in the form of smartphones and tablet PCs or notebooks having a mobile radio interface.

[0003] The mobile radio device comprises a chipset, at least one radio interface for a mobile radio network, and at least one configuration file by which the mobile radio device authenticates itself for providing services in a radio network of a mobile network operator.

[0004] The profiles are contained in the Subscriber Identity Module SIM in the mobile radio device, which is a secure enclave for profiles for the mobile radio device. SIMs for profiles are currently available on the market in the form of removable plug-in SIM cards, pSIMs or UICCs (UICC = Universal Integrated Circuit Card), as well as in the form of fixed soldered eSIMs or eUICCs (embedded SIM, embedded UICC), and in the form of integrated SIMs, iSIMs or iUICCs, integrated in a chip of the chipset of the mobile radio device.

[0005] According to the GSMA specification [1] SGP.22 RSP Technical Specification Version 3.0, 19 October 2022 (or simply SGP.22) and previous versions, a profile is "a combination of data and applications provided on an eUICC in order to provide a service" (1.5 Definition of Terms). This definition applies more or less to any profile, is also independent of SGP.22, and also applies to other form factors of the secure enclave besides the eUICC, such as a plug-in SIM card or UICC.

[0006] As described in [1] SGP.22, Section 3.1 and as described in this document Figure 1 The provision of the profile shown in implies the following steps: (i) initialization (Chapter 3.1.1), (ii) mutual authentication between SM-DP+ and eUICC (Chapter 3.1.2), and (iii) profile download and installation (Chapter 3.1.3).

[0007] According to [1] SGP.22 Chapter 2.4.5 "Configuration Files", a configuration file consists of the following configuration file components:

[0008] One MNO-SD

[0009] Supplementary Security Domain (SSD) and CASD

[0010] Small applications

[0011] Applications, such as NFC applications

[0012] NAAs (Network Access Applications)

[0013] Other elements of the file system

[0014] Profile metadata, including profile policy rules.

[0015] In particular, the profile comprises a subscriber identifier as one element of the profile. A 4G profile for a 4G mobile radio network (fourth generation mobile radio network) comprises an International Mobile Subscriber Identity IMSI as a subscriber identifier. A 5G profile for a 5G mobile radio network (fifth generation mobile radio network) comprises a Subscriber Permanent Identifier SUPI as a subscriber identifier.

[0016] Additional profile elements are the authentication key and the OTA key or a set of OTA keys.

[0017] Each profile is owned by a mobile network operator, MNO, and is dedicated to a specific mobile radio network associated with the MNO. Different profiles are usually provided for different networks of different MNOs. A SIM can host several profiles for several MNOs.

[0018] Document [2] [TS31.102] ETSI TS131 102 V17.5.0, Universal Mobile Telecommunications System (UMTS); LTE; 5G; Characteristics of the Universal Subscriber Identity Module (USIM) application from the prior art (3GPP TS 31.102 Version 17.5.0 Version 17), 2022-04 describes the characteristics of SIMs (referred to as UISMs in [2]) and the file structure of the SIM managed profile elements.

[0019] The user identifier is stored in the file ADFUSIM in the file system of the SIM.

[0020] According to [2] [TS31.102], Annex N, for 5G mobile radio networks, IMSI type and non-IMSI type SUPIs are known. IMSI type SUPIs are usually dedicated to public mobile radio networks. Non-IMSI type SUPIs are usually dedicated to private mobile radio networks.

[0021] A 5G network use case is the handover of connectivity between a public mobile radio network and a private mobile radio network. In a private mobile radio network, the network owner (e.g. a company) can establish a customized security and pricing architecture that is more suitable for the owner than the security and pricing architecture of the public mobile radio network. When the mobile radio device is under the coverage of the private radio network, a non-IMSI type profile including a non-IMSI type SUPI dedicated to the private radio network is used. Only when the mobile radio device leaves the coverage of the private radio network, the network connectivity is switched to an IMSI type profile including an IMSI type SUPI for the public mobile radio network.

[0022] In the SIM considered in [2] Annex N.2, a SIM enabling connectivity in both a public IMSI type mobile radio network and a private non-IMSI type mobile radio network is expected to include two complete profiles in parallel, namely one public profile including an IMSI type SUPI in its file system and one private profile including a non-IMSI type SUPI in its file system. In particular, [2] Annex N.2 explicitly assumes that both SIMs contain all mandatory EFs for the respective USIM applications. Therefore, having a public IMSI type profile and a non-IMSI type private profile in one SIM involves high memory consumption.

[0023] It would be advantageous to have a solution that can selectively connect to a private or public mobile radio network with reduced memory consumption.

[0024] Prior art document [3] WO2021089533A1 from Thales discloses a method for switching the value of a profile file set of an MNO (including SUPI) to a new value of the MNO of the visited country and routing the attachment request back to the network of the home MNO.

[0025] Prior art document [4] US10356569B2 from Verizon discloses a method comprising modifying a UICC so that it matches the network to which the device hosting the UICC is connected.

[0026] Purpose of the invention:

[0027] An object of the present invention is to provide a solution that enables switching connectivity between a first and a second mobile radio network with reduced memory consumption in the SIM. In particular, an object of the present invention is to provide a solution that enables switching connectivity between a first and a second mobile radio network with reduced memory consumption in the SIM, wherein one of the first and second mobile radio networks is a public IMSI type network and the other is a private non-IMSI type network. Summary of the invention

[0028] The object of the invention is achieved by a method according to claim 1 having the following features. Embodiments of the invention are presented in the dependent claims.

[0029] In more detail, the object of the present invention is achieved by a method for switching connectivity between a first mobile radio network and a second mobile radio network in a SIM hosted in a mobile radio communication device, the method comprising the following steps:

[0030] (1) operating the SIM with respect to connectivity in a first mobile radio network using a profile hosted in the SIM, the profile comprising a first ADF USIM file entry corresponding to the first mobile radio network,

[0031] (2) Switching connectivity using a configuration file hosted in the SIM to operate the SIM with respect to connectivity in a second mobile radio network, the configuration file comprising a second ADF USIM file entry corresponding to the second mobile radio network.

[0032] The method is characterized by:

[0033] - the first ADFUSIM entry and the second ADFUSIM entry are included in the same configuration file;

[0034] - Performing a switch of connectivity from the first mobile radio network to the second mobile radio network by switching configuration of the profile from using the first ADD USIM entry to using the second ADD USIM entry.

[0035] The ADFUSIM entry may be, for example, an identifier of an ADFUSIM application, in particular an AID of the ADFUSIM application, in particular a unique AID of the respective ADFUSIM application.

[0036] The configuration file including the first ADFUSIM entry and the second ADFUSIM entry enables the two configuration files to be included in a single configuration file in practice without having to provide the entire overhead of the configuration file twice. In particular, common files of the configuration file can be shared between the first and second ADFUSIM entries.

[0037] The invention therefore provides a solution which enables switching of connectivity between a first and a second mobile radio network with reduced memory consumption in a SIM.

[0038] According to some embodiments of the present invention, switching the configuration of the profile from using the first AD F U SIM entry to using the second AD F U SIM entry is performed by the following switching schedule:

[0039] - in order to perform step (1), operating the SIM in the first mobile radio network with respect to connectivity, providing an entry for an identifier of the first ADFUSIM, in particular an AID, in an elementary file directory EFDIR provided in the SIM;

[0040] - To perform step (2), switch connectivity to operate the SIM in terms of connectivity in a second mobile radio network, remove the identifier entry of the first ADFUSIM, in particular the AID, from the basic file directory EFDIR and enter the identifier entry of the second ADFUSIM, in particular the AID, into the basic file directory EFDIR.

[0041] In other words, before the connectivity switching, the identifier (AID) of the ADFUSIM application for the first mobile radio network is registered in the EFDIR, and in order to implement the connectivity switching, the identifier (AID) of the ADFUSIM application for the first mobile radio network is replaced with the identifier (AID) of the ADFUSIM application for the second mobile radio network in the EFDIR. According to a preferred embodiment, by modifying the application identifier (e.g., AID) of the ADFUSIM application from the first mobile wireless network to the second mobile wireless network in the basic file directory EFDIR, the connectivity of the SIM is implemented from the first mobile wireless network to the second mobile wireless network in a very efficient mode.

[0042] According to some embodiments of the present invention, along with ADFUSIM, all required or desired additional configuration file elements and / or file system entries are switched.

[0043] Therefore, according to some embodiments, together with the switching of ADFUSIM, a switching of one or several of the following configuration file elements and / or file system entries is performed:

[0044] - Authentication key;

[0045] - OTA key or OTA key set;

[0046] -EFDIR;

[0047] -EFAD;

[0048] -EFUST;

[0049] -EFLastADF;

[0050] -EF-SUCI_Calc;

[0051] -DF5G / AFSUPI_NAI.

[0052] According to some embodiments, the switching of one or several of the following profile elements is performed by one of the following switching schedules:

[0053] - providing only one profile element entry of ADFUSIM in the profile file, the profile element entry including the profile element entry of the first ADFUSIM and used to switch and update or overwrite the profile element entry of the first ADFUSIM with the profile element entry of the second ADFUSIM;

[0054] - Only one profile element entry of ADFUSIM is provided in the profile file, the profile element entry contains the profile element entry of the first ADFUSIM, and for switching, the profile element entry of the second ADFUSIM is created as a new profile element entry.

[0055] According to some embodiments,

[0056] - deactivating the configuration file element of the first ADFUSIM is achieved by removing the identifier entry of the configuration file element of the first ADFUSIM from the basic file directory EFDIR, in particular the AID; and

[0057] - The activation of the profile element of the second ADFUSIM is achieved by entering an identifier entry of the profile element of the second ADFUSIM, in particular the AID, into the basic file directory EFDIR.

[0058] According to some embodiments, one of the first and second mobile radio networks is a public IMSI type mobile radio network and the other mobile radio network is a private non-IMSI type mobile radio network.

[0059] According to some embodiments, the first mobile radio network is a 4G network, wherein the SIM comprises an entry in the ADFI SIM for the first mobile radio network, and the second mobile radio network is a 5G network, wherein the handover comprises the additional steps of:

[0060] - creating additional files required for such SUCI calculation for the second mobile radio network as 5G network in the file system of the profile;

[0061] - Download the SUCI calculation applet designed for SUCI calculation to the SIM, if and / or as needed, with the additional files required for SUCI calculation.

[0062] The profile for the 5G network requires the SUCI computing applet and some specific files required for SUCI computing, which are not required for the 4G profile. Therefore, when switching from 4G connectivity to 5G connectivity, the missing files must be created and the missing applet must be provided (e.g., downloaded).

[0063] According to some embodiments, additional files required for SUCI calculations are created along with switching the configuration to the second configuration file.

[0064] According to some embodiments, the second mobile radio network is a private mobile radio network.

[0065] In particular, the second mobile radio network may be a 5G proprietary mobile radio network. In this case, the first mobile radio network may be a 5G or 4G or 3G network.

[0066] According to some embodiments, the first mobile radio network is a 5G network, wherein the SIM comprises an entry in the EFUST for the first mobile radio network, and the second mobile radio network is a 4G or 3G network, wherein the handover comprises the additional steps of:

[0067] - Disable EFUST for the first mobile network.

[0068] EFUST is a file specific to 4G and 3G networks and is not required in 5G networks.

[0069] According to some embodiments, handover connectivity between the first mobile radio network and the second mobile radio network is initiated by a triggering event.

[0070] The triggering event may be or include one or more of the following:

[0071] - unavailability of the first mobile radio network at the device;

[0072] - user input at the user interface of the device;

[0073] - A user enters a machine readable code at the device.

[0074] The first triggering event, i.e. the unavailability of the first mobile radio network at the device, may mean an automatic connectivity switch from the unavailable first mobile radio network to the available second mobile radio network. Alternatively, when the first mobile radio network is unavailable, a user interaction may additionally be provided, for example when selecting the second mobile radio network from among several available mobile radio networks.

[0075] The second trigger event (user input at the user interface of the device) may be used as a single trigger to effect a switch in connectivity, for example an intentional switch initiated by the user. Alternatively, the user input may be used as a trigger in combination with unavailability of the first mobile radio network.

[0076] The third triggering event (user entry of a machine-readable code at the device) is preferably used for intentional switching initiated by the user. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Embodiments of the present invention will now be described with reference to the accompanying drawings, wherein like parts are designated by like reference numerals throughout, and wherein:

[0078] Figure 1 According to the prior art, files on a file system of an IMSI type and a non-IMSI type profile, and a merged profile containing files of both profiles;

[0079] Figure 2 According to an embodiment of the present invention, a file on a file system of a configuration file is configured. DETAILED DESCRIPTION

[0080] Figure 1 The files on the file system of the IMSI type profile 'Profile-1', the non-IMSI type profile 'Profile-2' and the merged profile 'Profile3' according to the prior art are shown. The files containing the IMSI type and non-IMSI type profiles.

[0081] exist Figure 1In the profile -1 of IMSI type, there is an entry of ADFUSIM of IMSI type and other required files of the profile, and there is no entry and required files of ADFUSIM of non-IMSI type. In addition, profile -1 has an entry of authentication key of ADFUSIM IMSI type, which is the only key in the basic file EF, especially Aupopk, EF_AUTH, EF_AUTPAR. In addition, profile -1 has an entry of OTA key of ADFUSIM IMSI type, which is the only key in the issuer security domain ISD or supplementary security domain SSD or file. The authentication key and OTA key of non-IMSI type ADFUSIM do not exist in profile -1.

[0082] exist Figure 1 In the non-IMSI type profile-2, the non-IMSI type ADFUSIM entry and other required files of the profile are present, and the IMSI type ADFUSIM entry and required files are not present. In addition, profile-2 has an entry for the authentication key of the non-IMSI type ADFUSIM, which is the only key in the basic file EF, in particular, Aupopk, EF_Auth, EF_Authpar. In addition, profile-2 has an entry for the OTA key of the non-IMSI type ADFUSIM, which is the only key in the issuer security domain ISD or in the supplementary security domain SSD or in the file. The authentication key and OTA key of the IMSI type ADFUSIM do not exist in profile-2.

[0083] exist Figure 1 , Profile-3 (assumed profile) has ADFUSIM and required files, authentication keys and OTA keys for both IMSI type and non-IMSI type, and all profile files of IMSI type and non-IMSI type provided twice ( Figure 1 (Not all are shown in the figure). For example, the EDIR may contain an IMSI-type ADFUSIM entry and a non-IMSI-type ADFUSIM entry.

[0084] Figure 2 Schematic diagram showing files on a file system of a configuration file according to an embodiment of the present invention.

[0085] Figure 2 The configuration file has a separate ADFUSIM file, which records the IMSI type ADFUSIM entries or non-IMSI type ADFUSIM entries.

[0086] exist Figure 2Initially, ADFUSIM contains an entry of IMSI type and does not contain an entry of non-IMSI type. When the terminal dials into a mobile radio network, it dials into the IMSI type mobile radio network corresponding to the IMSI type ADFUSIM entry.

[0087] At runtime, triggered by a triggering event, the ADFUSIM file is updated and thereby overwritten with the non-IMSI type ADFUSIM entries.

[0088] Therefore, the terminal cannot find the ADFU SIM entry of the IMSI type, but can only find the ADFU SIM entry of the non-IMSI type.

[0089] Thus, after the triggering event has occurred and the ADFUSM handover has been performed, the terminal will dial into the non-IMSI mobile radio network.

[0090] Associated with ADFUSIM, it is also possible to switch authentication keys.

[0091] Initially, the authentication unique keys of the IMSI type are contained in the elementary files EF for a single IMSI type network, such as Aupopk, EF_Auth, EF_Authpar.

[0092] According to the first option of the unique key, in parallel, a unique key of non-IMSI type may be pre-stored in a different elementary file EF with a different file ID and in a deactivated state.

[0093] At runtime, also triggered by a triggering event or in association with a triggered ADFUSIM switch, a deactivated non-IMSI type unique key pre-stored in a different EF / file ID is activated.

[0094] According to the second option for a unique key, a new key file is created, the new key is loaded from the network server to the SIM, which can be performed using the default network function.

[0095] Associated with ADFUSIM, OTA keys can also be switched.

[0096] Initially, for single IMSI type networks (3GPP), the OTA unique key for the IMSI type is contained in the ISD / SSD or file.

[0097] According to the first option of the OTA unique key, in parallel, the non-IMSI type OTA unique key can be pre-stored in the ISD or SSD or EF and is in a deactivated state.

[0098] At runtime, also triggered by a trigger event, or otherwise associated with a triggered ADFUSIM switch, activates the deactivated non-IMSI type OTA unique key pre-stored in ISD / SSD / EF.

[0099] According to the second option for OTA unique keys, a new key file is created and the new key is loaded from the network server to the SIM, which can be performed using the default network function.

[0100] Referenced Documents

[0101] [1][SGP.22] RSP Technical Specification Version 3.0, October 19, 2022 (or SGP.22 for short)

[0102] [2] [TS31.102] ETSI TS131 102 V17.5.0, Universal Mobile Telecommunications System (UMTS); LTE; 5G; Characteristics of the Universal Subscriber Identity Module (USIM) application (3GPP TS 31.102 Version 17.5.0 Version 17), 2022-04

[0103] [3] WO2021089533A1

[0104] [4]US10356569B2.

Claims

1. A method for switching connectivity between a first mobile radio network and a second mobile radio network in a SIM hosted in a mobile radio communication device, the method comprising the following steps: (1) operating the SIM with respect to connectivity in the first mobile radio network using a configuration file hosted in the SIM, the configuration file comprising a first ADFUSIM file entry corresponding to the first mobile radio network, (2) switching connectivity to operate the SIM with respect to connectivity in the second mobile radio network using a configuration file hosted in the SIM, the configuration file comprising a second ADF USIM file entry corresponding to the second mobile radio network, Features: - the first ADFU SIM entry and the second ADFU SIM entry are included in the same configuration file; - performing a switch of connectivity from the first mobile radio network to the second mobile radio network by switching configuration of the profile from using the first ADD USIM entry to using the second ADD USIM entry.

2. The method according to claim 1, wherein: The switching of the configuration of the profile from using the first AD F U SIM entry to using the second AD F U SIM entry is performed by the following switching schedule: - for performing step (1) of operating the SIM in terms of connectivity in the first mobile radio network, providing an entry for an identifier of the first ADFUSIM, in particular an AID, in an elementary file directory EFDIR provided in the SIM; -For executing step (2) switching connectivity to operate the SIM in terms of connectivity in the second mobile radio network, removing the identifier entry of the first ADFUSIM, in particular the AID, from the basic file directory EFDIR and entering the identifier entry of the second ADFUSIM, in particular the AID, into the basic file directory EFDIR.

3. The method according to claim 1 or 2, wherein: In conjunction with the switching of the ADFUSIM, a switching of one or more of the following configuration file elements and / or file system entries is performed: - Authentication key; - OTA key or OTA key set; -EFDIR; -EFAD; -EFUST; -EF previous ADF; -EF-SUCI_calculation; -DF5G / AFSUPI_NAI.

4. The method according to claim 3, wherein: Switching of one or more of the following profile elements is performed by one of the following switching schedules: - providing in the configuration file only one configuration file element entry of an ADFUSIM, the configuration file element entry including the configuration file element entry of the first ADFUSIM, and for the switching, updating or overwriting the configuration file element entry of the first ADFUSIM with the configuration file element entry of the second ADFUSIM; - Only one profile element entry of an ADFUSIM is provided in the profile file, the profile element entry contains the profile element entry of the first ADFUSIM, and for the switching, the profile element entry of the second ADFUSIM is created as a new profile element entry.

5. The method according to claim 3 or 4, wherein - deactivating the configuration file element of the first ADFUSIM is achieved by removing the identifier entry of the configuration file element of the first ADFUSIM from the basic file directory EFDIR, in particular the AID; and - Activating the configuration file element of the second ADFUSIM is achieved by entering an identifier entry, in particular an AID, of the configuration file element of the second ADFUSIM into the basic file directory EFDIR.

6. The method according to any one of claims 1 to 5, wherein: One of the first mobile radio network and the second mobile radio network is a public IMSI type mobile radio network, and the other mobile radio network is a private non-IMSI type mobile radio network.

7. The method according to any one of claims 1 to 6, wherein: The first mobile radio network is a 4G network, wherein the SIM comprises an entry in the ADFI SIM for the first mobile radio network, and the second mobile radio network is a 5G network, wherein the handover comprises the following additional steps: - creating additional files required for SUCI calculation for the second mobile radio network being a 5G network in the file system of the profile; - Downloading the SUCI calculation applet designed for SUCI calculation to the SIM, if and / or as needed, using said additional files required for SUCI calculation.

8. The method according to claim 7, wherein: Together with switching the configuration to the second configuration file, the additional files required for the SUCI calculation are created.

9. The method according to claim 7 or 8, wherein: The second mobile radio network is a private mobile radio network.

10. The method according to any one of claims 1 to 6, wherein: The first mobile radio network is a 5G network, wherein the SIM comprises an entry in an EFUST for the first mobile radio network, and the second mobile radio network is a 4G or 3G network, wherein the handover comprises the following additional steps: - Disable the EFUST of the first mobile network.

11. The method according to any one of claims 1 to 10, wherein: The handover connectivity between the first mobile radio network and the second mobile radio network is initiated by a triggering event.

12. The method according to claim 11, wherein: The triggering event is or includes one or more of the following: - unavailability of said first mobile radio network at said device; - user input at a user interface of the device; - A user inputs a machine readable code at the device.

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