GB2442565A

GB2442565A - Virtual subscriber identities for mobile communications networks

Info

Publication number: GB2442565A
Application number: GB0718797A
Authority: GB
Inventors: Tyrone Lee Martin Christie; Marlon Facey
Original assignee: T & M Wireless Ip Solutions Lt
Current assignee: T & M Wireless Ip Solutions Lt
Priority date: 2006-10-05
Filing date: 2007-09-26
Publication date: 2008-04-09
Also published as: WO2008040964A3; GB0718797D0; GB0619711D0; WO2008040964A2

Abstract

A virtual SIM system to enable the use of virtual SIMs from a single mobile communications device equipped with a master SIM related to the virtual SIMs. Virtual SIM systems connected to mobile communications networks provide processing and storage for providing services to subscribers and for storing virtual SIM information. Calls may be made from a mobile communications device equipped with the master SIM utilising a subscription of a virtual SIM, and calls directed to a virtual SIM may be routed to a mobile communications device equipped with a related master SIM. Apparatus and methods are provided for the creation, maintenance, use, registration and deregistration of virtual SIMs.

Description

Virtual Subscnber Identities for Mobile Communications Networks

Technical Field

1001] The present invention relates to mobile communications networks It is particulaily related to, but in no way limited to, the provision of multiple virtual subscnber identities for mobile communications networks

Background

[002] There are a growing number of people having more than one mobile communications subscription A person may have more than one subscription for a number of reasons, for example they may have a business and a personal number, or may have a subscnption to a number of different networks to enable them to benefit from special prices offered by each network It is also common for people to have a mobile network subscription in more than one country, such that they have a local presence in each country (003] In order to differentiate themselves mobile network operators may provide specialist or particular features to their subscribers For example they may offer particularly attractive pricing schemes for certain aspects of their services The availability of such different services and pricing from different network operators is a further factor in people having multiple mobile network subscriptions [004] Mobile network subscriptions are defined and accessed by placing a Subscriber Identity Module (SIM) in a mobile communications device, which SIM allows access to a particular subscription from that mobile communications device Each mobile network subscription is tied to a single SIM and that SIM must be used to access the subscnption. A user with multiple mobile network subscriptions must therefore have one mobile communications device for each subscription, or alternatively, swap the SIM in a single mobile communications device when they wish to change between subscriptions This is clearly inconvenient and a deterrent to having multiple subscriptions It would, however, be desirable to have multiple subscriptions active simultaneously, from a single mobile communications device [005] Mobile communications devices, which accept two SIMs, or adaptors to enable a device to accept Iwo SIMs, are available, but only one SIM can be active at any given time The user must therefore select which subscription they wish to have access to, and both cannot be active at the same time [006] In order for two subscriptions to be active from a single mobile telephone at one time, it would be necessary for the mobile telephone to contain duplicate SIM, processing and radio systems to handle both subscriptions concurrently Such a system would substantially increase the cost of the mobile telephone

Summary

According to a first aspect of the invention there is provided a communications network, comprising a virtual SIM system comprising a master virtual SIM system and a slave virtual SIM system, each being associated with a mobile communications network, the master virtual SIM system being configured to communicate with a mobile communications device registered on a mobile communications network with a master SIM, a memory at the master virtual SIM system storing a master virtual SIM comprising information relating to the identity of the master SIM, a memory at the slave virtual SIM system storing a slave virtual SIM comprising information relating to the identity of a slave SIM which is removed from the communications network, wherein each virtual SIM also comprises tags associating the virtual SIMs The communications network may further comprise a mobile communications device equipped with the master SIM Each of the virtual SIM systems may be associated with a mobile communications network of a different service provider The mobile communications device may be registered on a mobile communications network associated with the master virtual SIM system The mobile communications device may be registered on a mobile communications network associated with the slave virtual SIM system The information relating to the identity of the slave SIM may be selected from the IMSI of the SIM and the MSISDN of that SIM The information relating to the identity of the master SIM may be selected from the IMSI of the SIM and the MSISDN of that SIM Each of the mobile communications networks may compnse an HLR and the virtual SIM systems may be connected to the HLR of their respective mobile communications networks The master virtual SIM system and the slave virtual SIM system may be in communication The master virtual SIM system may be arranged to communicate with the mobile communications device using the USSD protocol The master virtual SIM system may be arranged to communicate with the mobile communications device using a session initiation protocol The session initiation protocol may be SIP A voice recognition system may be arranged such that a user of the mobile communications device may interact with the Master virtual SIM system.

The VSIM systems may each be integrated as part of the mobile communications network with which they are associated The master virtual SIM may identity a subscnption to a different mobile network than a subscription identified by the slave virtual SIM Alternatively, the subscription identified by the master virtual SIM may be a subscription to the same mobile network as the subscription identified by the slave virtual SIM The slave virtual SIM may contain information indicative of the functions and services available when the slave virtual SIM is accessed from a particular master SIM According to a second aspect of the invention there is provided, a method of creating a slave virtual SIM and associating that slave virtual SIM with a master SIM, the method being carried out at a slave virtual SIM system and comprising the steps of receiving information identifying a Slave SIM, creating a slave virtual SIM using the information received, receiving information identifying a master SIM to which the slave virtual SIM will be related, generating information relating the slave virtual SIM to the master SIM, and stonng that information in the slave virtual SIM, and transmitting the information identifying the master SIM, and the information relating the slave virtual SIM to the master SIM, to a master virtual SIM system associated with the master

SIM

The information identifying the Slave SIM and Master SIM may be received from a mobile communications device The information may be received from the mobile communications device utilising the USSO protocol Alternatively, the information may be received from the mobile communications device utilising a session initiation protocol The information relating the slave virtual SIM to the master SIM may comprise the MSISDN of the master SIM and the MSISDN of the slave virtual SIM The identifying information of the master SIM may comprise the MSISDN of the master SIM The method may further compnse the step of receiving user phone book information from the slave SIM and stonng that in the slave virtual SIM The method may further comprise the step of receiving a security code from the master virtual SIM system and transmitting that security code to the mobile communications device The method may further compnse the step of receiving a tagging code from the master virtual SIM system, further relating the master SIM to the slave virtual SIM The method may further compnse the steps of receiving information identifying a further Slave SIM from a mobile communications device having that SIM, creating a further Slave virtual SIM using the information received, generating information relating the further Slave virtual SIM to the Master SIM, and stonng that information in the further Slave virtual SIM, and transmitting the information identifying the Master SIM, and the information relating the further Slave virtual SIM to the Master SIM, to the Master virtual SIM system associated with the Master SIM The method may further compnse the steps of receiving information identifying a Further master SIM to which the slave virtual SIM will be related, generating information relating the slave virtual SIM to the further master SIM, and storing that information in the slave virtual SIM, and transmitting the information identifying the further master SIM, and the information relating the slave virtual SIM to the further master SIM, to a master virtual SIM system associated with the further master SIM The method may further comprise the step of storing information in a virtual SIM indicative of the handling of incoming calls to that virtual SIM According to a third aspect of the invention, there is provided a method of creating a slave virtual SIM and associating that slave virtual SIM with a master SIM, the method being carried out at a mobile communications device and comprising the steps of registering the mobile communications device on a mobile communications network utilising a slave SIM for which it is desired to create a slave virtual SIM, transmitting a request to a slave virtual SIM system associated with the slave SIM to create a slave virtual SIM corresponding to the slave SIM, transmitting information relating to the identity of the slave SIM to the slave virtual SIM system, and transmitting information identifying a master SIM to which the slave virtual SIM will be related The information relating to the identity of the slave SIM may comprise information selected from the MSISDN and the IMSI of the slave SIM The information relating to the identity of the master SIM may be the MSISDN of the master SIM The step of transmitting information relating to the identity of the slave SIM may be performed automatically under the control of at least one USSD command received by the mobile communications device The method may further comprise the step of receiving a code for use in completing the relationship between the slave virtual SIM and the master SIM.

The method may further comprise the steps of registering a mobile communications device on a mobile communications network utilising the master SIM, and transmitting the code to a master virtual SIM system associated with the master SIM The method may further comprise the step of transmitting information identifying at least one further master SIM to which the slave SIM will be related The method may further compnse the steps of registering the mobile communications device on a mobile communications network utilising a further slave SIM for which it is desired to create a further slave virtual SIM, transmitting a request to a further slave virtual SIM system associated with the further stave SIM to create a further slave virtual SIM corresponding to the further slave SIM, transmitting information relating the identity of the further slave SIM to the further slave virtual SIM system, and transmitting information identifying a master SIM to which the further slave virtual SIM will be related According to a fourth aspect of the invention there is provided a method of enabling a communication between a mobile communications device having a master SIM and a destination.

utilising a slave virtual SIM, the method being carried out at a master virtual SIM system and comprising the steps of. receiving a request from the mobile communications device to establish a communication using a slave virtual SIM, requesting information from a slave virtual SIM system relating to the slave virtual SIM, receiving the requested information, instructing the mobile network of the master SIM to establish the communication, and transmitting to the mobile network of the master SIM information relating to the slave virtual SIM for use when establishing the communication The communication being established may be a voice call Alternatively, the communication being established may be the transmission of an SMS message The master virtual SIM system and the slave virtual SIM system may be associated with mobile communications networks of different service providers The request from the mobile communications device may be received utilising the USSD protocol The request from the mobile communications device may be received utilising a session initiation protocol The caller ID of the Slave VSIM may be utilised to identify the onginator of the call Alternatively, the caller ID of the Master VSIM may be utilised to identify the onginator of the call The method may further compnse the step of instructing the slave virtual SIM system to indicate that a call is in progress utilising the virtual SIM The method may further compnse the step of receiving information relating to credit associated with the subscription of the Slave VSIM According to a fifth aspect of the invention, there is provided a method of enabling receipt of a communication at a mobile communications device having a master SIM, the originating party having directed the communication to the MSISDN of a slave virtual SIM associated with the master SIM, the method being performed at a slave virtual SIM system storing the slave virtual SIM and comprising the steps of identifying the destination MSISDN as relating to a virtual SIM, retrieving details of the master SIM, to which the slave virtual SIM is related, from the slave virtual SIM, determining the current location of a mobile communications device having the master SIM, and instructing a communications network to route the communication to the mobile communications device having the master SIM.

The communication being received may be a voice call Alternatively, the communication being received is an SMS message The current location of the mobile communications device may be determined by requesting that information from an HLR associated with the master SIM Information may be transmitted to the mobile communications device indicating that the call was directed to the MSISDN of the slave virtual SIM The method may further compnse the step of indicating that a call is in progress utilising the slave virtual SIM and master SIM The method may further comprise the steps of inspecting a phone book associated with the slave VSIM to ascertain the identity of the originating party, and, if that information is available, transmitting the identity to the destination A processing system may be configured to perform the steps of any of the above methods According to a sixth aspect of the invention, there is provided a method of deregistering a virtual SIM, the method being performed at a slave virtual SIM system having a slave virtual SIM and comprising the steps of receiving a request from a mobile communications device registered on a mobile network with a slave SIM associated with the slave virtual SIM, the request being to deregister the slave virtual SIM, transmitting a request to a master virtual SIM system to remove references to the slave virtual SIM from a master virtual SIM related to the slave virtual SIM, and deleting the slave virtual SIM According to a seventh aspect of the invention, there is provided a method of establishing a communication from a mobile communications device having a master SIM, utilising a slave virtual SIM, the method being carried out at a slave virtual SIM system and comprising the steps of receiving a request from the mobile communications device to establish a communication using a slave virtual SIM, requesting information from a master virtual SIM system relating to the master virtual SIM, receiving the requested information, instructing the mobile network of the slave virtual SIM to establish the communication, and transmitting to the mobile network of the slave virtual SIM information relating to the slave virtual SIM for use when establishing the communication (007) A computer program stored on a computer readable medium may be arranged to control a processor to perform the steps of any of the above methods (008] The method may be performed by firmware or software in machine-readable form on a storage medium (009] This acknowledges that firmware and software can be valuable, separately tradable commodities It is intended to encompass software, which runs on or controls "dumb" or standard hardware, to carry out the desired functions For similar reasons, it is also intended to encompass software which "describes' or defines the configuration of hardware, such as HDL (hardware description language) software, as is used for designing silicon chips, or for configuring universal programmable chips, to carry out desired functions (010] The preferred features may be combined as appropriate, as would be apparent to a skilled person, and may be combined with any of the aspects of the invention

Brief Description of the Drawings

[0111 Embodiments of the invention will be descnbed, by way of example, with reference to the following drawings, in which Figure 1 is a schematic diagram of a telephone system having two mobile telephone networks according to the pnor art, Figure 2 is a schematic diagram of the system of Figure 1, each mobile network having a Virtual SIM system, Figure 3 is a flow diagram of the process of creating a slave VSIM, Figure 4 is a flow diagram of the process of creating a Master VSIM,

Figure 5 shows the fields of a VSIM,

Figure 6 shows the fields of a Master VSIM,

Figure 7 is a flow diagram of the process of deregistering a slave virtual SIM, Figure 8 is a more detailed diagram of the networks shown in Figure 2, Figure 9 is a flow diagram of a process of making a call using a VSIM, Figure 10 is a network diagram indicating the flow of signals during the making of a call to a VSIM, Figure 11 is a flow chart of a process of placing a call to a VSIM Figure 12 is a schematic diagram of the networks shown in Figure 2 when the mobile communications device is roaming on the Slave network Figure 13 shows the fields of a Mail Box data structure Figure 14 is a flow chart of a process of sending an SMS message.

Figure 15 is a flow chart of a process of receiving an SMS message Figure 16 is a flow chart of a process of placing a call from a VSIM when the mobile communications device is roaming on the slave network; Figure 17 is a flow chart of the process performed by a VSIM system to place a call from a VSIM Figure 18 shows the fields of a VSIM for use in an IMS network, and Figure 19 shows the flow of signals during the placing of a call from a VSIM in an IMS network

Detailed Description

[012] Embodiments of the present invention are described below by way of example only These examples represent the best ways of putting the invention into practice that are currently known to the Applicant although they are not the only ways in which this could be achieved [0131 Figure 1 shows a network diagram of a mobile telephone system Mobile telephone networks 1, 2 are conventional mobile networks, for example GSM networks SIM cards 3, 4 relate to subscriptions to the networks 1 2 In conventional systems, if SIM cards 3, 4 were owned by the same person, they could not be active simultaneously, unless used in separate mobile communications devices As has been descnbed previously, that is undesirable for various reasons [014] The following description is made primarily with reference to GSM mobile telephone systems, but the systems and methods are equally applicable to other mobile telephone network standards, for example COMA (IS-95) or packet-switched protocols such as IMS, with appropriate modifications as will be apparent to the person skilled in the art [015) Figure 2 shows a mobile telephone system, including the networks of Figure 1 Mobile networks 1, 2 are provided with Virtual SIM (VSIM) systems 20, 21 which enable both SIMs 3, 4 to be active simultaneously, from a single mobile communications device 22 The VSIM systems are configured such that they can communicate between themselves, and also to the mobile networks 1, 2. Those communications may utilise standard protocols associated with the mobile networks 1 2, for example in GSM networks the SS7 protocol may be employed 10161 One of the SIMs, 3, is designated the Master SIM and is utilised in the user's mobile communications device to access the subscriptions of SIMs 3 and 4 SIM 4 is virtuabsed into the VSIM system 21 according to the methods described herein and is not physically used During that virtualisation a Master VSIM 23 is created in VSIM system 20 and contains details of the Master SIM 3 and a Slave VSIM 24 is created in VSIM system 21 Master VSIM 23 and Slave VSIM 24 also contain data relating the two VSIMs to each other As in conventional systems, each SIM 3, 4, and hence each VSIM 23, 24 relates to an MSISDN and an IMSI 10171 When a call is placed to or from the MSISDN to which the Master SIM 3 relates, it proceeds according to conventional principles and is routed via mobile network 1 from or to the mobile communications device 22 equipped with the SIM 3 The VSIM systems enable mobile communications device 22 to place and receive calls from and to the MSISDN and IMSI of the SIM 4, without deactivating SIM 3, as would have to be done in the prior art (018] When a call is placed to the MSISDN to which SIM 4 relates the MSISDN is identified as having a Slave VSIM 24 related to Master VSIM 23 VSIM systems 20, 21 thus relate the MSISDN of SIM 4 to the MSISDN of the Master SIM 3 and route the call via the mobile network 1 to the mobile communications device 22 equipped with the Master SIM 3 [0191 To place a call from mobile communications device 22, equipped with Master SIM 3, but using the subscnption of SIM 4. the mobile communications device 22 interacts with VSIM systems 20, 21 to obtain the subscription details of SIM 4 from the VSIM 24 The call is routed as if it originates from Master SIM 3, but may appear to the destination as a call from SIM 4 depending upon the configuration of the VSIM systems 20, 21 in relation to the particular VSIM being used A billing or charging system is agreed between the mobile networks 1, 2 such that charging is performed depending on the VSIM services utilised Information may be exchanged between mobile networks 1, 2 and VSIM systems 20, 21 such that the correct charges are made For example, the cost of the call may be placed on the account of SIM 4, but mobile network 1 may charge mobile network 2 for handling the call That charge may be passed to the subscnber, or may be met from a VSIM subscription fee paid by the subscriber [020] Text messages handled by the SMS service of mobile networks may be treated in the same manner as calls, thereby enabling the sending and receipt of SMS messages to and from multiple mobile subscriptions using a single mobile communications device A detailed description of SMS services using VSIM systems is given below [021] GSM provides a session-based communications protocol entitled Unstructured Supplementary Service Data (USSD), which allows communication between a mobile communications device and the Home Location Register (HLR) of a SIM in that mobile communications device The VSIM systems 20, 21 are connected to the HLR of their respective mobile network, and it is therefore possible to utihse the USSD protocol to communicate between a mobile communications device and the VSIM system USSD may therefore be utilised in the systems and methods descnbed herein, but other communications systems or protocols may also be utilised For example, the SIM Application Toolkit (SAT) functionality may be utilised The description in relation to USSD and GSM in no way limits the systems and methods to those standards 1022] In order to utilise the subscription of SIM 4 from mobile communications device 22 equipped with SIM 3, a VSIM 24 must first be created corresponding to SIM 4 For convenience VSIM 24 and SIM 4 are described as Slave' VSIMs and SIMs That is to differentiate them from the Master SIM 3 and Master VSIM 23 which are used to access the Slave VSIM 24. The term is a convenient identifier and does not imply any limitation or actions of either of the VSIMs or SIMs [023] Figure 3 shows a flow diagram of the creation of a Slave VSIM 24 for the SIM 4.

[024] The user inserts 30 the SIM 4 (which is to become the slave SIM) into a mobile communications device 22 The mobile communications device may, conveniently, be that which will be used by the user to access the subscnptions, but may be any mobile communications device The mobile communications device registers 31 under the subscnption of SIM 4 as 1 5 normal Communications are then initiated 32 between the mobile communications device and the Slave's VSIM system 21 Those communications may be initiated by the user entering a USSD code, or may, as mentioned above, use different techniques, for example the SAT The USSD protocol provides a convenient method of implementation since USSD messages are routed to the HLR of the SIM and therefore the network on which the mobile communications device is currently registered does not affect operation of the system If other systems are utilised correct routing of messages back to the HLR (and hence VSIM system) of the SIM may have to be arranged (025) A Slave VSIM 24 is created 33 in the Slave's VSIM system 21 and the relevant information copied from the Slave SIM 4 to the Slave VSIM 24 Network information relating to the subscription of the SIM is copied, for example the IMSI and MSISDN, together with user defined information, which may include telephone books stored on the SIM Details of the information are given below in the description of the VSIM data stwcture The data may be copied from the SIM to the VSIM in a number of ways The USSD protocol provides an instruction facility, which enables a USSD message to be sent to a mobile communications device to instruct the mobile communications device to reply with information from the SIM of that mobile communications device The (JSSD session may therefore be utilised to automate the copying of information from the SIM to the VSIM Alternatively, the SAT and/or software downloaded to the mobile communications device may be utilised to send the information from the mobile communications device to the VSIM Furthermore, the user could manually input data for transfer to the VSIM system The upload of data over the mobile network may be performed using the USSD session, or may utilise other communications protocols For example, a protocol providing additional security or error checking may be provided to ensure the data is uploaded securely and to reduce errors in the uploaded data [026) The Masters MSISDN (i e the telephone number of the SIM card that the user will use in the mobile communications device when accessing the subscription of the Slave SIM 4) and details of the Masters mobile network are transmitted 34 from the mobile communications device 22 to the Slave's VSIM system 21 The user may enter these details or the user may enter the MSISDN and the VSIM system will identify the network from the number The Masters network identity enables the Slave's VSIM system 21 to identify the correct VSIM system 20 containing the Masters SIM 23 The Slave's VSIM system 21 generates 35 a VSIM tag which it forwards to the Masters VSIM system 20, together with the Master's MSISDN and slave SIMs MSISDN The VSIM tag is an identifier to allow the Master VSIM system to identify the particular Slave VSIM The Masters VSIM system 20 checks 36 whether a VSIM exists for the MSISDN provided, and if not creates 37 a Master VSIM 23 [027] The VSIM tag and MSISDN of the slave SIM sent by VSIM system 21 is added 39 to the Master VSIM 23 thereby linking the Master and Slave VSIMs. A security code is generated 301 which is stored in the Master VSIM 23 and transmitted to the Slave's VSIM system 21 The Slave's VSIM system 21 forwards 302 the secunty code to the user The user will require the code when registering the Master SIM 3 and completing the link to the slave VSIM 24 The process of creation of a slave VSIM is then complete [028] The above process may be repeated for any further SIMs, which the user wishes to relate to the Master SIM, such that a single Master SIM is related to a plurality of Slave SIMs A Slave VSIM is created for each SIM, and a respective VSIM tag is entered ri the Master VSIM A different security code will be issued for each SIM so registered [0291 The above process for the creation of VSIMs is carried out utilisirig a mobile communications device, however it is also possible to create VSIMs using other mechanisms For example an Internet service may be provided for subscribers to access the virtual SIM systems and to create and amend VSIM5 relating to thatsubscriber Other services may also be provided for subscribers to create and amend VSIM5, for example telephone customer support or voice-recognition systems [030] To complete the relationship between a Master SIM and a Slave VSIM, the Master VSIM is completed The Master VSIM is completed and linked to the Slave VSIM by communication between a mobile communications device 22 equipped with the Master SIM 3 and the VSIM system 20 of the Master SIM 3 Figure 4 shows a flow chart of the process for completion of the Master VSIM 23 and linking to the Slave VSIM 24 [031] The Master SIM 3 is inserted 40 into a mobile communications device 22 The Master SIM registers 41 on a mobile network 1 as normal Communications are initiated 42 between the mobile communications device 22 and the Master's VSIM system 20 Mobile communications device 22 then indicates that the user wishes to complete the Master VSIM The communications may be initiated by the entry of a USSD code into the mobile communications device 22 or by other means, for example SAT The mobile communications device is shown in Figure 2 as being registered on its home network 1. However, that is for convenience and the mobile communications device may actually be registered on any network, provided suitable communications can be established between the mobile communications device and the Masters VSJM system 20 The USSD protocol is a convenient way of providing such communications [032] The Mastefs VSIM system 20 identifies 43 that a Master VSIM 23 exists for the Master SIM 3 and requests that a security code is sent The user inputs that security code and it is sent 44 to the master's VSIM system 20 which checks 45 that the code matches that previously sent to the Slave's VSIM system 21 If the secunty code received by the Master's VSIM system 20 is incorrect, no action need be taken, but the code may be requested again or an error message generated If the security code received is correct, a Master tag code is generated 46 and stored in the Master VSIM A tagging code is then generated using the Master tag code and Slave tag code and is transmitted to the Slave's VSIM system for storage 47 in the Slave's VSIM [033] VSIM entities 23, 24 thereby exist for the Master SIM 3 and the Slave SIM 4, and are linked by the tagging codes exchanged between the VSIM systems 20, 21 The VSIM systems 20, 21 (and hence the Mobile networks 1, 2) can therefore identify that a particular MSISDN, corresponds to a Slave VSIM 4 and can route services, for example calls and SMS messages, and other information related to that MSISDN and IMSI to the Master SIM 3 (034] After completion of the registration process, the Slave SIM 4 has been virtualised into a VSIM 24, and is no longer physically used The Master SIM 3 does have a corresponding VSIM 23, but the physical SIM 3 is still used to access the mobile network, to use the subscription of that SIM, and the subscriptions identified by its VSIM 23 [035] The VSIM systems 20, 21 have been described as separate systems to the mobile networks 1, 2 but the VSIM systems may alternatively be integrated into the mobile network equipment of the mobile networks 1, 2 The functionality is not changed by this integration, but a more efficient operation may be obtained. For example, the VSIM systems may be integrated into the HLR of the mobile network as either additional software on that system, or as a system closely linked to the HLR The equipment into which the VSIM systems may be integrated depends upon the type of network and the equipment present within the particular network [036] If more than one Slave VSIM has been created relating to a single Master VSIM the above process is repeated for each Slave VSIM [037] The VSIMs and associated data structures will now be described in greater detail [038) Figure 5 shows the data structure of a Slave VSIM 50 The data of the VSIM 50 can be split into two principle sections -network information 51, relating to technical details of the subscription to the mobile network, and user data 52, which relates to data that would, in a conventional mobile telephone system, be stored in the SIM card The following entries are available in the VSIM, not all of which are necessarily required for every Slave VSIM Label' -This is a unique label for the VSIM. Itis formed of two parts, an alphanumeric part which may be user defined, and a part which represents the unique ICCID of the SIM to which the VSIM relates Master Network' -The identity of the mobile network of the Master SIM to which the VSIM is related Master MSISDN' -The MSISDN of the Master SIM to which the VSIM is related Slave MSISDN' -The MSISDN ci the subscription to which the VSIM relates VSIM IMSI' -The IMSI of the subscription to which the VSIM relates VSIM Tag' -Tagging code of the Slave VSIM, created during registration Tagging Code' -Code utilised to relate Slave VSIMs to Master VSIMs The structure of the tagging code is explained in detail below.

CLIP, CLIR Flags' -Flags to indicate to the network whether to utilise these services for 1 5 the subscription.

Calling/SMS Flags' -Flags to act as status parameters that aid the Master network in differentiating between Master and VSIM signals, and to indicate call status Other Network parameters -Placeholders for network parameters that may be stored as required VSIM phonebook' -Phonebook of numbers for this VSIM Entries may initially be uploaded from the SIM during registration, and subsequently edited, deleted or added to, via the VSIM system, for example utilising USSD messages to interact with the VSIM system VSIM SMS messages' -SMS messages to or from the VSIM MSISDN.

Other user data -Storage space for other data relating to the user, as required.

(039] Figure 6 shows the data structure of a Master VSIM Since the Master SIM is present in the mobile telephone, user information can be stored in and accessed from the SIM, and so a Master VSIM has no user data section VSIM MSISDN' -MSISDNs of Slave SIMs Master IMSI' -The IMSI of the Master subscription Master MSISDN' -MSISDN of the Master subscription Master Tag' -The tagging code of the Master VSIM Tagging Code' -Code utilised to relate Slave VSIMs to Master VSIMs The structure of the tagging code is explained in detail below Calling/SMS Flags' -Flags to act as status parameters that aid the Master network in differentiating between Master and Slave VSIM signals, and to indicate call status Other network parameters' -Placeholders for network parameters that may be stored as desired [040] The tagging code, which is stored in both the Master VSIM, and the Slave VSIM, is a unique number that relates a Master VSIM to a Slave VSIM The number consists of a concatenation of the Master tag, the VSIM tag and a serial number The tagging code is required by the Master VSIM system to access the Slave VSIM This is one example of a possible structure of the tagging code As will be apparent, other schemes are also possible for a tagging code that performs the function required.

10411 Figure 7 shows a flow chart of the deregistration process for of a slave SIM A subscriber may wish to remove the relationship between a master SIM and a slave SIM, and that is accomplished by the process of deregistration The user registers 600 a mobile communications device on a mobile network utilising the slave SIM that they wish to deregister A request is sent 601 to the slave virtual SIM system to initiate the deregistration process That instruction may be sent by the user entering a USSO code into the mobile communications device to initiate a USSD session, or software may be downloaded to the mobile communications device to enable the user to initiate the process The slave VSIM system requests 602 the master SIM's MSISDN in order to verify that the correct relationship will be removed That MSISDN is entered by the user into the mobile communications device and transmitted to the slave virtual SIM system, for example utilising the USSD session Alternatively, the MSISDN may be selected using a menu system provided by the communications device [042] The user is then given the option 603 of downloading any user information stored in the slave VSIM to the mobile communications device Should the user elect to transfer the user information back to the mobile communications device, that information is transmitted 604 utilising the USSD session, or other communications system being used for the process. The information may be copied to the slave SIM by USSD commands sent to the mobile communications device, which enable access to the SIM without input from the user.

Alternatively, the information may be stored in memory of the mobile communications device Once any user data has been transmitted, the virtual slave SIM is deleted 605 from the slave I, virtual SIM system and an instruction is sent 606 to the master virtual SIM system to remove the tagging code relating to the slave virtual SIM from the master virtual SIM The slave SIM is thereby removed the virtual SIM systems and can be used as a conventional SIM [043] Figure 8 shows a more detailed network diagram of a mobile telephone and VSIM system for providing VSIM services Mobile communications device 22 is equipped with Master SIM 3 which corresponds to a Master VSIM 23 held in the VSIM system 20 of the Master mobile network 1 VSIM system 21 holds a Slave VSIM 24 Slave VSIM 24 has been related to Master VSIM 23, as descnbed previously [0441 VSIM system 20 is connected to the HLR 70 of the Masters mobile network 1, and also to the MSC 71 of that network VSIM system 21 is connected the HLR 72 of the Slave VSIMs mobile network 2 VSIM system 21 may also be connected to the MSCNLR of mobile network 2, but that connection is not required for the current description and so is omitted for clarity [045] For clarity, VStM system 20 will be referred to as the Master VSIM system and VSIM system 21 will be referred to as the Slave VSIM system The systems are, however, the same, and this is simply a naming convention for clarity The names do not imply any particular functionality, and VSIM system 21 can also store Master VSIMs and provide the services described in relation to Master VSIM system 20, and vice-versa [046] Calls may be placed to and from the MSISDN of the Master SIM 3 normally, and the VSIM systems 20, 21 do not need to play any part in the calls However, for billing purposes, the VSIM systems 20. 21 may be notified.

1047] The process of placing a call from mobile communications device 22, but using the subscription of VSIM 24, will now be described with reference to Figures 8 and 9 The process is described with reference to the use of USSD codes for interaction with the VSIM system, but other methods of interaction are also possible, as has been previously described.

10481 Mobile communications device 22 is equipped with Master SIM 3 and registered on mobile network 1 For the purposes of this explanation, the Master SIM 3 relates to a subscription to Mobile network 1 If the mobile communications device 22 is registered on a different network when attempting to make a call with VSIM 24 the process is somewhat different, and is explained in detail below [049] The menu system may enable the user to access user data stored in the VSIM to be used for the call For example, phonebook entries may be utilised to find the number to be called To provide such access contact is made between VSIM systems 20, 21 using the tagging code to access the Slave VSIM.

[050] To initiate a call, the user enters 80 a USSD service code on the mobile communications device 22 indicating the SIM subscription they wish to place the call from The service code is transmitted 81 to the MSC 71 and on to the HLR 70, which recognises it as relating to the VSIM system A USSD session is then established 82 between the Mobile communications device 22 and the VSIM system 20 During this session the user may switch to the desired VSIM subscription and select other options, the VSIM system may hold this state information regarding the users selection and VSIM subscnption or it maybe stateless information Stateless implies that the user must redefine which subscription and options they wish to use preceding each call In Figure 8, a gateway 73 is provided between the HLR 70 and the VSIM system 20 to pass and receive USSD messages, the gateway is not essential but is used in this description, as described previously, the VSIM system may also be integrated into the FILR or other network equipment The user exits the USSD session and initiates a call 83 [051] The MSC interrogates the HLR to acquire subscriber information, the HLR responds and call control is handed over to the VSIM system 84.

[052] The Master VSIM system 20 then contacts 87 the Slave VSIM system 21 holding the VSIM 24 that the user has indicated they wish to use for the call The Master VSIM system 20 may form part of a network of VSIM systems, each associated with a different mobile network The correct VSIM system for a given VSIM entity may be determined from the tagging code held in the Master VSIM [053) The subscnption information of the VSIM 24 is then requested 88 from Slave VSJM system 21 The required information may include details of the subscription to the VSIM service, details of the mobile subscription represented by the VSIM arid billing details Some details may not be held in the VSIM system, and may be obtained from the HLR 72 of the VSIM 24 Billing details relevant to the VSIM may include whether the subscnption is a pre-or post-pay subscription Checks are made to ensure the subscnption has sufficient credit or a high enough credit limit, and the allowable length of call may be transmitted to the Master VSIM system 20 such that the call can be terminated should the subscription's credit or credit limit be exceeded [054) The requested information is transmitted 89 to the Master VSIM system 20, which uses the information to confirm 801 that the requested call can be placed Information relating to the credit of a pre-pay subscnption may be transmitted to the mobile communications device for the user's information Presuming the call can be placed, the master VSIM system 20 hands call control back to the MSCNLR 71 to commence the call The MSCNLR 71 proceeds to establish 803 the call to the destination 10551 Call establishment proceeds according to conventional processes -the MSC 71 sets up a call to the destination recipient, and once the recipient of the call has responded, a circuit is established to the mobile communications device 22 A difference, however, is that the MSC 71 may utilise details from the VSIM 24, as provided by the Master VSIM system 20, such that it appears to the recipient of the call that the call is originating from the VSIM subscnption as opposed to the Master SIM subscription. The call, however, is routed as a normal call from Master SIM 3 Once the call is established, it proceeds as a standard mobile call from mobile communications device 22 and is terminated accordingly [056] MSC 71 may notify the Master VSIM system 20 that the call has terminated such that details of the call can be passed to the Slave VSIM system 21 to be recorded for administrative purposes Furthermore, billing information may be exchanged between the MSC 71 HLR 70, VSIM systems 20, 21 and HLR 72 [057] When the call is established, the VSIM system 21 may be notified, such that call flags in the VSIM 24 may be set to indicate that that subscription is being utilised for a call. Any incoming calls to that subscnption can therefore be handled accordingly -for example, the calls may be diverted to an alternative number (e g Voicemail) or the caller may be notified that the number is busy That functionality may be provided by conventional systems of the HLR 72 or by additional services provided by VSIM system 21.

[058) The process of establishing a call to a VSIM subscription will now be described with reference to Figures 10 and 11 (059] Figure 10 shows a schematic diagram of parts of a telephone network relevant to the routing of a call to an MSISDN of a VSIM 24, to the mobile communications device 22 registered with the Master SIM related to that VSIM from a telephone 96 GMSC 90 Is connected to PSTN 91 and is the appropriate GMSC for MSISDNs associated with HLR 92 The MSISDN of the VSIM 24 is associated with the HLR 92, which in addition to the conventional services provided by an HLR, is also connected to a VSIM system 93 Mobile communications device 22 is equipped with Master SIM 3 and is registered in the VLR served by VMSC 94 (which may or may not be its home network) The HLR of the Master SIM 3 is shown at 95 and that HLR also is also connected to a VSIM system 97 10601 At step 101 Caller A dials the MSISDN of the VSIM 24 The call is routed 102 through the PSTN 91 to the competent GMSC 90, which queries 103 the appropriate HLR 92 to obtain the current routing information for the MSISDN The MSISDN is recognised as corresponding to a VSIM and the HLR queries the VSIM system 93 to obtain the details of the Master SIM (i.e the MSISDN/lMSl) The recognition of the MSISDN as corresponding to the VSIM 24 may be performed by the storage of that information in the HLR record for the MSISDN, or the VSIM system 93 may intercept the query to the HLR 92 Details of the Master SIM 3 are retrieved 105 from the VSIM 24 and sent to the HLR 92 [061] The HLR 92 requests routing information for the Master SIM 3 from the HLR 95 of the Master SIM In alternative configurations, VSIM system 93 may send the request directly to the HLR 95 [0621 The Masters HLR 95 has a record of the current VLR of the Master SIM, and forwards 107 the IMSI of the Master SIM to the appropriate VMSCNLR 94 to obtain routing information VMSCNLR 94 replies 108 to the Masters HLR 95 with an MSRN for the Master SIM 3. The Masters HLR 95 forwards 109 the MSRN to the GMSC 90 The information may be sent either via the HLR 92, or directly to the GMSC 90 as shown in Figure 10 [0631 GMSC 90 then completes 110 the call to Master SIM 3 as a conventional call The call of user A to the MSISDN of the VSIM 24 has therefore been routed to the mobile communications device equipped with Master SIM related to that MSISDN The call may be billed in the conventional manner, or billing information may be exchanged with HLR 95 and VSIM systems 93, 97 and a bill raised according to the service provided [0641 The phone book of the slave VSIM 24 may be queried during the process of receiving a call, and if the number of the calling party is present in that phone book, the identity of the person having that number may be transmitted with the call such that the receiving party knows the identity of the calling party 1 5 [065] The description hereinbefore has been in relation to the mobile communications device being located in its home network, and therefore having direct access to that network When a mobile communications device is roaming on a different network the signal flow during use of VSIM functionality is different, but the general principles remain the same [066] Figure 12 shows the network of Figure 6, but in Figure 12 the mobile communications device 22 is registered on the Slave VSIM's mobile network 2 Calls can be made to and from the MSISDN of the Master SIM 3 in the normal way using conventional routing for a roaming SIM Figure 16 shows a method of making a call using a VSIM subscription from a mobile communications device roaming in a Slave VSIM network.

[0671 In order to utilise the VSIM functionality, the mobile communications device 22 must be, as in Figure 12, roaming on the VSIM network 2 The mobile communications device equipped with Master SIM 3 is therefore configured to select that network when in a roaming environment That configuration may be performed by manually selecting the network to utilise, or alternatively an application may automatically select the network to utilise Although the mobile communications device 22 is registered on the mobile network 2 of the Slave VSIM 24, it is the subscription of the Master SIM 3 that is utilised by the mobile communications device 22 to register and to make and accept calls as in conventional systems [068] To initiate a call, the user enters 120 a USSD service code on the mobile communications device 22 indicating the SIM subscription they wish to place the call from. The service code is transmitted 121 to the VMSC 112 and on 111 to the home HLR 70, which recognises it as relating to the VSIM system 20 A USSD session is then established 122 between the Mobile communications device 22 and the VSIM system 20 During this session the user may switch to the desired VSIM subscnption and select other options, the VSIM system 20 may hold this state information regarding the users selection and VSIM subscription or it maybe stateless information Stateless implies that the user must redefine which subscription and options they wish to use preceding each call In Figure 12, a gateway 73 is provided between the HLR 70 and the VS$M system 20 to pass and receive USSD messages, the gateway is not essential but is used in this descnption, as described previously, the VSIM system 20 may also be integrated into the HLR or other network equipment. The user exits the USSD session and [Comment: The exit does not I occur here because the master initiates a call 123. I has not checked ihai the user can make a call using their slave subscnptuon i e [069] The VMSCNLR 112 interrogates the home HLR 70 to acquire subscriber information restrictions or barring, aiso if L!ere is sufficient credit This is due to the fact that the Master SIM 3 is not recognised as a local subscriber on the Slave network 2 The Master SIM 3 is recognised as a subscriber of the Master network 1 (roaming partner) and therefore the VMSCNLR 112 would have been configured to be able to address the home HLR 70 The HLR 70 responds with the subscriber information 124 and call control 113 is handed over to the Master VSIM system 20 1 5 [070] The Master VSIM system 20 then contacts 125 the Slave VSIM system 21 holding the VSIM 24 that the user has indicated they wish to use for the call The Master VSIM system 20 may form part of a network of VSIM systems, each associated with a different mobile network The correct VSIM system for a given VSIM entity may be determined from the tagging code held in the Master VSIM (0711 The subscnption information of the VSIM 24 is then requested 126 from Slave VSIM system 21 The required information may include details of the subscription to the VSIM service, details of the mobile subscription represented by the VSIM 24 and billing details Some details may not be held in the VSIM system, and may be obtained from the HLR 72 by the VSIM system 21 Billing details relevant to the VSIM may include whether the subscription is a pre-or post-pay subscription Checks are made to ensure the subscription has sufficient credit or a high enough credit limit, and the allowable length of call may be transmitted to the Master VSIM system 20 such that the call can be terminated should the subscription's credit or credit limit be exceeded (072) The requested information is transmitted 127 to the Master VSIM system 20, which uses the information to confirm that the requested call can be placed Information relating to the credit of a pre-pay subscnption may be transmitted to the mobile communications device for the users information Presuming the call can be placed 128, the master VSIM system 20 hands call control 113 back to the VMSCNLR 112 to commence the call 129 The VMSCNLR 112 proceeds to establish 130 the call to the destination [073] Call establishment precedes 130 according to conventional processes -the VMSCNLR 112 sets up a call to the destination recipient, and once the recipient of the call has responded, a circuit is established to the mobile communications device 22 A difference, however, is that the VMSC/VLR 112 may utilise details from the VSIM 24, as provided by the Master VSIM system 20, such that it appears to the recipient of the call that the call is originating from the Stave VSIM 24 as opposed to the Master SIM 3 subscription The call, however, is routed as a normal call from mobile communications device 22 Once the call is established 130, it proceeds as a standard mobile call from mobile communications device 22 and is terminated accordingly [074) VMSCNLR 112 may notify the Master VSIM system 20 that the call has terminated such that details of the call can be passed to the Slave VSIM system 21 to be recorded for administrative and billing purposes Furthermore, billing information may be exchanged between the VMSC/VLR 112 and other elements in the Slave network 2 such as billing & charging systems (075] When the call is established 130, the VSIM system 21 may be notified, such that call flags in the VSIM 24 and VSIM 23 may be set to indicate that that subscnption is being utilised for a call Any incoming calls to that subscription can therefore be handled accordingly -for example, the calls may be diverted to an alternative number (e g Voicemail) or the caller may be notified that the number is busy That functionality may be provided by conventional systems of the HLR 72 and or 70 or by additional services provided by VSIM system 21 and or 20 [076] The VSIM and MSC/HLR systems may exchange information with regard to billing and initiation/termination of the call such that the correct subscriptions can be billed for the call, and so that correct indications can be provided while the call is ri progress should a further user attempt to call either the MSISDN of the Master SIM 3, or that of the Slave VSIM 24 (077] Calls made to an MSISDN of a Slave VSIM associated with a Master currently roaming on a non-home network proceed as described previously with reference to Figures 10 and 11 [078) Mobile telephone networks also provide the functionality to send and receive short text message via the Short Messaging System (SMS). Figure 13 shows a data structure of a mailbox 1100 for storing SMS messages relating to a VSIM The following entnes are available in the mailbox, not all of which are necessarily required in every case Label' -this is a unique label for the mailbox that identifies the VSIM to which the mailbox relates *SMS memory not exceeded flag' -a flag utilised to indicate when the mailbox is full and hence that no further SMS messages can be stored in that mailbox Other parameters' -other parameters relating to the functionality of SMS message handling may also be stored in the mailbox SMS messages (N)' -a number of entries for the storage of SMS messages may be provided in the mailbox Each SMS message may be stored as a separate entry in the mailbox The storage space allocated to the mailbox and the size of each SMS message will define how many SMS messages can be stored in the particular mailbox [079] Figure 14 shows a flowchart of the process of sending an SMS message from a mobile communications device equipped with a Master SIM using the subscnption of a Slave VSIM associated with that Master SIM The user of the mobile communications device enters 1110 a USSD code to indicate that they wish to send an SMS message from their mobile communications device utilising the subscription of a Slave VSIM As has been descnbed previously a USSO session is initiated 1111 between the mobile communications device and the Master VSIM system corresponding to the SIM of that mobile communications device The user enters 1112 the message to be sent together with the destination for the message The destination of the message may be entered into the mobile cornniunications device, or alternatively a destination stored in the Master or Slave VSIM systems may be utilised. Access to the address books of the VSIM systems occurs as described previously [080) The Master VSIM system communicates with the Slave VSIM system to establish 1113 details of the Slave VSIM and to confirm that the user has a suitable subscription (for example, sufficient funds) to allow the sending of the SMS message Those communications are carried out as has been described previously in relation to the placing of calls from a mobile communications device [081) Once it has been established that the text message can be sent, the Master VSIM system forwards 1114 the message to the appropriate SMSC from where the SMS message proceeds to be sent to the destination according to conventionalpnnciples 1115 [082) The Master VSIM system may provide either the Masters MSISDN or the MSISDN of the Slave VSIM as the sender of the SMS message dependent upon the settings of the users subscription The Master and/or Slave VSIM systems may record details of the SMS message sent for billing purposes Provided the SMS message has been correctly received by, and sent by, the SMSC a confirmation may be sent from the SMSC to the Master VSIM system which may then forward that information to the mobile communications device either as part of the USSD session or as an SMS message to inform the user that the message has been sent (083] Figure 15 shows a flowchart of an SMS message being sent to a mobile communications device equipped with a Master SIM corresponding to a Slave VSIM, the MSISDN of which VSIM us the destination of the SMS message The SMS message is received by the SMSC and forwarded to the SMS-GMSC via an interface 1120 The SMS-GMSC generates 1121 a routing enquiry to determine a route for delivery of the SMS message to the destination. That enquiry is intercepted 1122 by the VSIM system The VSIM system analyses the destination MSISDN of the SMS message and identifies 1123 that MSISDN as being a VSIM The tagging code of the VSIM is read and the Master network and Master MSISDN determined from it Those details are sent 1124 to the SMS-GMSC such that the message can be forwarded 1125 to the Master VSIM system corresponding to the Master SIM. The Master VSIM system stores 1126 the SMS message in a mailbox associated with the Master VSIM [0841 The Master VSIM system generates an SMS message for sending to the mobile communications device equipped with the Master SIM to alert the user of that mobile communications device to the fact that they have an SMS message awaiting them at the master VSIM system The Master VSIM system interacts 1128 with the relevant SMSC-GMSC to determine the location of, and to deliver the SMS to, the mobile communications device equipped with the Master SIM That SMS message is delivered to the mobile communications device according to conventional principles [0851 When the user receives the SMS message they may access 1129 the message at the Master VSIM system by entering a USSD service code to establish a session with the Master VSIM system The message may be viewed by the use of a menu system in the USSD session as has been described previously (0861 In an alternative method of delivering SMS messages to that described above the Master VSIM system may forward the actual SMS message to the mobile communications device as opposed to sending a standard SMS message highlighting the presence of an SMS message at the Master VSIM system [0871 The sending and receipt of SMS messages from and to a mobile communications device when that mobile communications device is registered on a network other than the Master network proceeds similarly to the above description. The modifications to those methods are equivalent to the changes to the making and receiving of calls and will be apparent to the person skilled in the art [0881 A USSD session may be utilised to manage SMS messages stored on a VSIM system, for example a menu system similar to that provided on conventional mobile telephones to manage SMS messages stored on that telephone may be provided to manage the messages on the Slave VSIM system The VSIM systems may also be utilised to store a record of SMS messages sent from a VSIM subscription such that those messages are kept separate from SMS messages sent from the Master VSIM, which would be stored on the mobile communications device equipped with the Master SIM The SMS messages may be stored in additional entries in the VSIM data structure, or alternatively in a mailbox as described above in relation to figure 13 [089] Figure 17 shows a generalised view of the steps performed by the VSIM system independent of the mobile network within which the VSIM system has been implemented [0901 The VSIM system receives 130 call control from a mobile communications network to place a call to a destination using a Slave VSIM related to the SIM with which the mobile communications device is registered The VSIM system retrieves 131 information required to access the Slave VSIM from a Master VSIM representing the SIM of the mobile communications device That information may include the MSISDN of the Slave VSIM arid the tagging code The VSIM system accesses the Slave VSIM and retrieves 132 information required to place the call -for example billing and subscnption information The Slave VSIM may be stored on the same VSIM system as the Master VSIM or on a different VSIM system connected thereto The VSIM system hands call control 133 back to the mobile network to connect a call from the mobile communications device to the destination, but to indicate that the call onginated from the VSIM subscription The call is connected to the destination mobile network in the conventional manner (091) As has been described VSIMs may contain user data such as phonebooks and calendars Access to that data may be gained from a mobile communications device equipped with a Master SIM related to the VSIM to which access is required A USSD service code is entered which is forwarded to the HLR of the Master SIM The HLR recognises the code as being a VSIM related code and forwards it to the Master's VSIM system thereby establishing a VSIM session to the Masters VSIM system By interaction with the mobile communications 1 5 device, the Master VSIM system receives the identity of the Slave VSIM to which access is required arid details of the information required The tagging code of the Master VSIM is then used to access the Slave VSIM and to recover the data required, which is then forwarded to the Mobile communications device By the exchange of LJSSD messages, the data of a VSIM may be edited, deleted or added to Furthermore, a menu system may be provided by the USSD session to provide convenient interaction with the VSIM system However, only the user data of the VSIM can be edited in this fashion -the network details section cannot be edited as that information is required for correct operation of the system and is not generally of relevance to the user [092] The description hereinbefore has related to the implementation of a VSIM system over circuit-switched telephone systems, such as GSM. The IP Multimedia Subsystem (IMS) provides a standardised architecture for mobile and fixed multimedia services, utilising packet switched systems The VSIM system operates over an IMS network according to the same principles as explained in relation to circuit switched systems In conjunction with IMS based networks, the VSIM system may also be extended to multimedia services [093] Figure 18 shows a VSIM containing additional parameters for use in an IMS system The additional parameters included in the VSIM are -VSIM UICC Card ID -Unique identifier of the UICC (Universal Integrated Circuit Card) associated with the VSIM IMS Private User ID' -Each IMS user has an IMS Private ID assigned by the network operator The ID is used to perform registration and other network functions for a given subscnption The ID is stored in the VSIM such that the VSIM system can perform the functions that would normally be performed by the UlcC IMS Public User ID -Each IMS user has a public user ID, used by other parties to identify the user The ID is equivalent to an MSISDN Home network URI -A unique Session Initiation Protocol (SIP) address that uniquely identifies the home network of the subscnption [094] Within the IMS network, a VSIM service may be provided either on an Application Server (AS) based on the network operators core network, or via a third party connection to that network VSIM systems may use SIP, SDP or MIME protocols to communicate over the IMS network or other IP protocols to facilitate application-to-application communications [095] Figure 19 shows an example of the flow of communications messages during the placement of a call from a mobile communications device 150 registered in the home network 151 of the Master SIM, using a Slave VSIM of VSIM network 152 to call a party in network A 153 Figure 19 shows an overview of the flow of messages As will be understood by the person 1 5 skilled in the art, further messages are required according to the ETSI 3GPP standard to accomplish the steps exemplified in Figure 19 [096) The mobile communications device transmits a signal 160, to initiate a first SIP session, to the home S-CSCF (Serving-Call Session Control Function) 154 of the subscription identified by the SIM in the mobile communications device The name/address (IMPI or IMPU) of the mobile communications device is recognised by the S-CSCF 154 as being subscribed to the VSIM service That recognition may be performed based on a filter file transferred to the S-CSCF 154 from an HSS (Home Subscriber Server) dunng registration of the particular SIM. The filter file identifies/enables the appropnate application server to be activated [097) The S-CSCF 154 forwards the signal 161 to the Master VSIM system 155 via the ISC interface The Master VSIM system 155 recognises the IMPI or IMPU in the signal and accesses the appropriate Master VSIM The Master VSIM system can then interact with the mobile communications device to determine the details of the call to be made -for example the destination of the call and from which number the call should appear to originate This process is equivalent to that described above in relation to a VSIM system implemented on a GSM network [098) The Master VSIM system 155 transmits a signal 163 to initiate an SIP session with the Slave VSIM network 152 The Slave VSIM network 152 is identified by the parameters stored in the Master VSIM during set-up of the VSIM system. The signal is sent via the ISC interface to the S-CSCF 154 [099) The S-CSCF 154 forwards the signal 163 to the Slave VSIM networks l-CSCF 156 [0100] The l-CSCF 156 forwards the signal 164 to the relevant S-CSCF 157 that can interact with the Slave VSIM system 158 [01011 The S-CSCF 157 forwards the signal 165 to the Slave VSIM system 158 via the ISC interface A communications session has thereby been initiated between the Master VSIM system and the Slave VSIM system The session may then be utilised to exchange information between the Master and Slave VSIM systems 155, 158 For example security details, such as the tagging codes, may be exchanged to verify the identity of the VSIM systems and particular subscriptions SDP/MIME may be used to communicate between systems [0102] Once the session has been initiated and the security steps completed, Master VSIM system 155 can interact 166 with Slave VSIM system 158 to initiate a call Communications between the Master VSIM system 155 and the Slave VSIM system 158 are via the S-CSCF The Master VSIM system 155 uses SOP (Session Description Protocol) in conjunction with MIME (Multipurpose Internet Message Extension) to communicate 166 with the Slave VSIM system 158 For example, a request may be created to ask for information relating to subscription services, access rights, restrictions and billing pnor to placing a call The Label of the appropriate VSIM is sent such that information relating to the correct VSIM is accessed The IMPI of the VSIM service subscriber may also be sent [0103) The Slave VSIM system uses the direct Cx interface and other interfaces to connect 167, 168 to the HSS and Billing system to obtain the requested information [100] Slave VSIM system 158 transmits the requested information 169, 169a and 170 to the Master VSIM system The session may then be terminated by the Master VSIM system 1101] Master VSIM system 155 instructs 171 the S-CSCF 154 to place a call to the required destination The Master VSIM system also sends the VSIM subscriber's caller ID, called party's APN (Access Point Name) and caller ID detail as appropriate, depending upon the settings of the user with regard to which subscription calls should appear to originate from The call is then made 172, 173 according to standard procedures [102] The general principles of operation over an IMS network are therefore the same as for GSM, and other, circuit switched networks, but the details are adapted to operate with the protocols and systems of the particular network standard The receiving of calls operates in an equivalent fashion to the detailed description in relation to a circuit switched network and it will be apparent to the person skilled in the art how that may be adapted to operate on an IMS network [103] Mobile systems operating using IMS may provide other services in addition to voice calls and SMS messaging, for example data services may be offered Such services may be handled by the VSIM system in an equivalent fashion to the description hereinbefore relating to voice calls and SMS messages.

(104] Throughout the description reference has been made to VSIM systems as discrete systems, with one system being related to one mobile network This is one possible configuration, but equally, a centralised, or shared, configuration may provide the same functionality For example, such configurations may be utilised in intelligent networks The description is not therefore intended to restrict the implementation of the invention to any particular configuration Equally, the VSIM systems need not be associated with particular networks, but may be shared between many networks [1051 The above description has described the Master and Slave SIMs as being related to subscriptions to different mobile networks However, those subscriptions may also be different subscriptions to the same mobile network In that situation, a single VSIM system performs the functionality of the Master and Slave VSIM systems and stores both VSIMs The operation of such a system is substantially the same as described previously, but the communications between Master and Slave VSIM systems are internal to a single VSIM system.

[106] The above description has been in relation to the use of a single Master SIM, relating to one or more VSIMs The opposite case of a single VSIM being related to multiple Master SIMs is also possible The creation of multiple Master SIMs relating to a single VSIM allows access to a single MSISDM and subscription from multiple mobile communications devices each having a Master SIM related to the VSIM For example, a company may wish to utilise a common telephone number for multiple telephones, or a family may wish to provide access to a common subscription for emergency use by their children should the child's own subscription run out of funding [107J Multiple Master SIMs may be created using the methods of Figures 3 and 5, suitably modified such that the Slave VSIM contains additional entries for each Master SIM to which it is related The Slave VSIM will then contain a unique tagging code for each Master VSIM By the addition of extra parameters to the Slave or Master VSIMs it is possible to provide different permissions for each Master SIM For example, one Master SIM may be permitted to make and receive calls using the Slave VSIM, but other Master SIMs may only be permitted to receive calls Furthermore, different access rights to, for example, the VSIM phone book may be provided for each Master SIM The permission associated with each Master SIM is accessed by the Master VSIM system when checking subscription details with the Slave SIM when making or receiving a call If a particular Master SIM does not have the required permission, the call is declined and the mobile communications device may be informed accordingly [108] The foregoing description in relation to the making and receiving of calls is intended to refer to both voice calls and other types of calls, for example data calls In addition, it is applicable to SMS messages and other types of communication [109) The Slave VSIM system may also contain additional parameters relating to the use of multiple Master SIMs For example, a priority list for the destination of incoming calls, such that a call is initially directed to one Master SIM, but should that call fail, it is directed to subsequent SIMs [1101 Throughout the description the user of the mobile communications device having the relevant SIM performs the selection of a VSIM to use However, the VSIM systems may provide additional functionality whereby the best VSIM to use for a given function may be selected automatically by that VSIM system For example when the user requests a call to be made to a certain number the VSIM system may check which VSIM associated with that Master SIM would give the best service, for example the cheapest, and utilise that VSIM for that call Any specified criteria may be used to make the selection [1111 The terminology, and in particular the acronyms, used herein in relation to descriptions of the mobile telephone networks and operation thereof is standard terminology that will be understood by the skilled reader Unless otherwise specified all network systems and operations are as in a standard telephone network, operating according to the established standards Accordingly, the functions of each part of the network are not limited by the functions described herein, but each part also performs its standard functions. The description of functions is therefore in addition to, as opposed to in place of, standard functions of the mobile telephone network [1121 The title mobile communications device' has been used throughout The use of that term will be understood to include mobile telephones and mobile data terminals, in addition to any mobile device providing those or other features [113) Throughout, the use of the word system' is not intended to imply any particular form of the item described, and accordingly, the item described may be implemented as a hardware device, a collection of interconnected hardware devices, a software program or any combination thereof, or any other device capable of providing the functionality of the system described herein [114] The use of the word simultaneously' is intended to indicate that more than one subscription may be active at any time and that use of more than one subscription may be possible Clearly, it may not be possible for a single user to actively use each subscription at the same time, and such a reading of the word is not intended, although may apply to certain uses of the systems and methods described herein [1151 Throughout, the word communicate' (and its cognate terms) is used to indicate both uni-and bi-directional communications, initiated by either end of the communications. The word is used for communications between machines and between people The word is therefore applicable to voice calls, data calls, SMS, MMS and other message types and data communications between systems El 16) Any range or device value given herein may be extended or altered without losing the effect sought, as will be apparent to the skilled person (117] The steps of the methods described herein may be carried out in any suitable order, or simultaneously where appropriate.

[1 18) It will be understood that the above description of a preferred embodiment is given by way of example only and that those skilled in the art may make various modifications [119) The phrase processing system' is used to refer to any electronic, or similar, system capable of processing data For example, the processing system may be a computer system or a microprocessor, as is well known in the art Furthermore, ASICs, FPGAs and CPLD fall within the scope of a processing system and may be used to implements parts, or all, of the systems and methods described herein El 20] The use of the acronym SIM' throughout is not intended to limit the description claims to systems or standards that generally utilise that acronym The acronym is used for convenience to describe a part that performs the functions descnbed The part described by the acronym therefore includes the equivalent part of different standards in which different acronyms are utilised, for example, ISIM, USIM and RSIM all fall within the meaning of SIM 1121) The acronym SMS' is used to refer in general to textual, graphical or data messages and as such incorporates SMS and MMS messages in the GSM standard as well as equivalent messaging systems in other standards and protocols [122] As will be appreciated, a particular MSISDN may relate to both a slave VSIM and a Master VSIM [1231 As will be understood by the person skilled in the art, the relationship between the various data structures described in relation to the systems and methods is a logical relationship which does not depend upon the physical location of those data structures For example, VSIMs have been described as being stored in the VSIM systems, but parts of each VSIM may be stored in different parts of a network whilst maintaining the required logical relationship For example the MSISDN of a particular VSIM may be stored in the HLR of an appropriate network, while the user data sections of the VSIM may be stored in a VSIM system.

[124J Interaction between users and the VSIM systems has been described pnncipally in relation to the use of USSD sessions to provide that interaction. As has been mentioned in respect of the registration of a VSIM, other methods of interaction may also be provided. For example, an Internet, call centre or voice recognition service may be provided to enable users to interact with the systems The systems and methods described previously are applicable to such interaction methods, with appropriate, obvious, alterations with regard to the source and destination of communications with the user.

[125] As will be apparent to the person skilled in the art, features of the apparatus and methods described herein are interchangeable Accordingly features of the apparatus and system described previously may be utilised in the method, and features of the method may be incorporated into the features provided by the system and apparatus

Claims

1 A communications system, comprising a virtual SIM system compnsing a master virtual SIM system and a slave virtual SIM system, each being associated with a mobile communications network, the master virtual SIM system being configured to communicate with a mobile communications device registered on a mobile communications network with a master SIM, a memory at the master virtual SIM system storing a master virtual SIM comprising information relating to the identity of the master SIM, a memory at the slave virtual SIM system storing slave virtual SIM comprising information relating to the identity of a slave SIM which is removed from the communications network, wherein each virtual SIM also comprises tags associating the virtual SIMs 2 A communications network as claimed in claim 1, further compnsing a mobile communications device equipped with the master SIM.

3 A communications network as claimed in claim 1 or claim 2, wherein each of the virtual SIM systems is associated with a mobile communications network of a different service provider 4 A communications network as claimed in claim 2, wherein the mobile communications device is registered on a mobile communications network associated with the master virtual SIM system A communications network as claimed in claim 2 wherein the mobile communications device is registered on a mobile communications network associated with the slave virtual SIM system.

6 A communications network as claimed in any preceding claim, wherein the information relating to the identity of the slave SIM is selected from the IMSI of the SIM and the MSISDN of that SIM 7 A communications network as claimed in any preceding claim, wherein the information relating to the identity of the master SIM is selected from the IMSI of the SIM and the MSISDN of that SIM 8 A communications network as claimed in any preceding claim, wherein each of the mobile communications networks comprises an HLR and wherein the virtual SIM systems are connected to the HLR of their respective mobile communications networks 9 A communications network as claimed in any preceding claim, wherein the master virtual SIM system and the slave virtual SIM system are in communication A communications network as claimed in any preceding claim, wherein the master virtual SIM system is arranged to communicate with the mobile communications device using the USSD protocol 11 A communications network as claimed in any preceding claim, wherein the master virtual SIM system is arranged to communicate with the mobile communications device using a session initiation protocol 12 A communications network as claimed in claim 11, wherein the session initiation protocol isSIP 13 A communications network as claimed in any preceding claim, comprising a voice recognition system arranged such that a user of the mobile communications device may interact with the Master virtual SIM system 14 A communications network as claimed in any preceding claim, wherein the VSIM systems 1 5 are each integrated as part of the mobile communications network with which they are associated A communications network as claimed in any preceding claim, wherein the master virtual SIM identifies a subscription to a different mobile network than a subscnption identified by the slave virtual SIM 16 A communications network as claimed in any one of claims ito 14, wherein the subscription identified by the master virtual SIM is a subscription to the same mobile network as the subscription identified by the slave virtual SIM 17 A communications network as claimed in any preceding claim, wherein the slave virtual SIM contains information indicative of the functions and services available when the slave virtual SIM is accessed from a particular master SIM 18 A method of creating a slave virtual SIM and associating that slave virtual SIM with a master SIM, the method being carried out at a slave virtual SIM system and comprising the steps of receiving information identifying a Slave SIM, creating a slave virtual SIM using the information received, receiving information identifying a master SIM to which the slave virtual SIM will be related, generating information relating the slave virtual SIM to the master SIM, and storing that information in the slave virtual SIM, and transmitting the information identifying the master SIM, and the information relating the slave virtual SIM to the master SIM, to a master virtual SIM system associated with the master

SIM

19 A method as claimed in claim 18, wherein the information identifying the Slave SIM and Master SIM is received from a mobile communications device A method as claimed in claim 18, wherein the information is received from the mobile communications device utilising the USSD protocol 21 A method as claimed in claim 18, wherein the information is received from the mobile communications device utilising a session initiation protocol 22 A method as claimed in claim 18 or claim 20, wherein the information relating the slave virtual SIM to the master SIM comprises the MSISDN of the master SIM and the MSISDN of the slave virtual SIM 23 A method as claimed in any of claims 18 to 22, wherein the identifying information of the master SIM compnses the MSISDN of the master SIM.

24 A method as claimed in any of claims 18 to 23, further comprising the step of receiving user phone book information from the slave SIM and stonng that in the slave virtual SIM A method as claimed in any of claims 18 to 24, further comprising the step of receiving a security code from the master virtual SIM system and transmitting that security code to the mobile communications device 26. A method as claimed in any of claims 18 to 25, further comprising the step of receiving a tagging code from the master virtual SIM system, further relating the master SIM to the slave virtual SIM 27 A method as claimed in any of claims 18 to 26, further comprising the steps of receiving information identifying a further Slave SIM from a mobile communications device having that SIM, creating a further Stave virtual SIM using the information received, generating information relating the further Slave virtual SIM to the Master SIM, and storing that information in the further Slave virtual SIM, and transmitting the information identifying the Master SIM, and the information relating the further Slave virtual SIM to the Master SIM, to the Master virtual SIM system associated with the Master SIM 28 A method as claimed in any of claims 18 to 27, further comprising the steps of receiving information identifying a further master SIM to which the stave virtual SIM will be related, generating information relating the slave virtual SIM to the further master SIM, and storing that information in the slave virtual SIM, and transmitting the information identifying the further master SIM, and the information relating the slave virtual SIM to the further master SIM, to a master virtual SIM system associated with the further master SIM 29 A method as claimed in any of claims l8to 28, further comprising the step of storing information in a virtual SIM indicative of the handling of incoming calls to that virtual SIM A method of creating a slave virtual SIM and associating that slave virtual SIM with a master SIM, the method being carried out at a mobile communications device and comprising the steps of registering the mobile communications device on a mobile communications network utilising a slave SIM for which it is desired to create a slave virtual SIM, transmitting a request to a slave virtual SIM system associated with the slave SIM to create a slave virtual SIM corresponding to the slave SIM, transmitting information relating to the identity of the slave SIM to the slave virtual SIM system, and transmitting information identifying a master SIM to which the slave virtual SIM wilt be related 31 A method as claimed in claim 30 wherein the information relating to the identity of the slave SIM comprises information selected from the MSISDN and the IMSI of the slave SIM 32 A method as claimed in claim 30 or claim 31 wherein the information relating to the identity of the master SIM is the MSISDN of the master SIM.

33 A method as claimed in any of claims 30 to 32, wherein the step of transmitting information relating to the identity of the slave SIM is performed automatically under the control of at least one USSD command received by the mobile communications device 34 A method as claimed in any of claims 30 to 33, further comprising the step of receiving a code for use in completing the relationship between the slave virtual SIM and themasterSiM A method as claimed in claim 34, further comprising the steps of registering a mobile communications device on a mobile communications network utihsing the master SIM. and transmitting the code to a master virtual SIM system associated with the master SIM 36 A method as claimed in claim 35, further comprising the step of transmitting information identifying at least one further master SIM to which the slave SIM will be related 37 A method as claimed in any of claims 30 to 36, further comprising the steps of registering the mobile communications device on a mobile communications network utilising a further slave SIM for which it is desired to create a further slave virtual SIM, transmitting a request to a further slave virtual SIM system associated with the further slave SIM to create a further slave virtual SIM corresponding to the further slave SIM, transmitting information relating the identity of the further slave SIM to the further slave virtual SIM system, and transmitting information identifying a master SIM to which the further slave virtual SIM will be related 38 A method of enabling a communication between a mobile communications device having a master SIM and a destination, utilising a slave virtual SIM, the method being carried out at a master virtual SIM system and comprising the steps of receiving a request from the mobile communications device to establish a communication using a slave virtual SIM, requesting information from a slave virtual SIM system relating to the slave virtual SIM, receiving the requested information, instructing the mobile network of the master SIM to establish the communication, and transmitting to the mobile network of the master SIM information relating to the slave virtual SIM for use when establishing the communication 39 A method as claimed in claim 38, wherein the communication being established is a voice call 40 A method as claimed in claim 38 wherein the communication being established is the transmission of an SMS message 41 A method as claimed in claim 38, wherein the master virtual SIM system and the slave virtual SIM system are associated with mobile communications networks of different service providers 42 A method as claimed in claim 38 or claim 41, wherein the request from the mobile communicationsdevice is received utilising the USSO protocol 43 A method as claimed in claim 38 or claim 41, wherein the request from the mobile communications device is received utilising a session initiation protocol.

44 A method as claimed in any of claims 38 to 43, wherein the caller ID of the Slave VSIM is utilised to identify the originator of the call A method as claimed in any of claims 38 to 43, wherein caller ID of the Master VSIM is utilised to identify the originator of the call 46 A method as claimed in any of claims 38 to 45, further comprising the step of instructing the slave virtual SIM system to indicate that a call is in progress utilising the virtual SIM 47 A method as claimed in any of claims 38 to 46 further comprising the step of receiving information relating to credit associated with the subscription of the Slave VSIM 48 A method of enabling receipt of a communication at a mobile communications device having a master SIM, the originating party having directed the communication to the MSISDN of a slave virtual SIM associated with the master SIM, the method being performed at a slave virtual SIM system storing the slave virtual SIM and comprising the steps of identifying the destination MSISDN as relating to a virtual SIM, retrieving details of the master SIM, to which the slave virtual SIM is related, from the slave virtual SIM, determining the current location of a mobile communications device having the master SIM, and instructing a communications network to route the communication to the mobile communications device having the master SIM.

49 A method as claimed in claim 48, wherein the communication being received is a voice call A method as claimed in claim 48, wherein the communication being received is an SMS message 51 A method as claimed in claim 48, wherein the current location of the mobile 1 5 communications device is determined by requesting that information from an HLR associated with the master SIM 52 A method as claimed in claim 48, wherein information is transmitted to the mobile communications device indicating that the call was directed to the MSISDN of the slave virtual

SIM

53 A method as claimed in claim 48, further comprising the step of indicating that a call is in progress utilising the slave virtual SIM and master SIM 54, A method as claimed in any of claims 48 to 53 further comprising the steps of inspecting a phone book associated with the slave VSIM to ascertain the identity of the originating party, and, if that information is available, transmitting the identity to the destination 55 A computer program stored on a computer readable medium and arranged to control a processor to perform the steps of any of claims 18 to 54 56. A processing system configured to perform the steps of any of claims 18 to 54 57 A method of deregistenng a virtual SIM, the method being performed at a slave virtual SIM system having a slave virtual SIM and compnsing the steps of receiving a request from a mobile communications device registered on a mobile network with a slave SIM associated with the slave virtual SIM, the request being to deregister the slave virtual SIM, transmitting a request to a master virtual SIM system to remove references to the slave virtual SIM from a master virtual SIM related to the slave virtual SIM, and deleting the slave virtual SIM 58 A method of establishing a communication from a mobile communications device having a master SIM, utilising a slave virtual SIM, the method being carried out at a slave virtual SIM system and comprising the steps of receiving a request from the mobile communications device to establish a communication using a slave virtual SIM, requesting information from a master virtual SIM system relating to the master virtual SIM, receiving the requested information, instructing the mobile network of the slave virtual SIM to establish the communication, and transmitting to the mobile network of the slave virtual SIM information relating to the stave virtual SIM for use when establishing the communication