GB2435156A

GB2435156A - Communication system for accessing more than one device at a single address

Info

Publication number: GB2435156A
Application number: GB0602731A
Authority: GB
Inventors: Jeffrey Wilson
Original assignee: Intellprop Ltd
Current assignee: Intellprop Ltd
Priority date: 2006-02-10
Filing date: 2006-02-10
Publication date: 2007-08-15
Also published as: GB0602731D0

Abstract

A mobile communication system is provided in which a subscriber may have two or more communication devices associated with a single public address. A store 6 for the user's public addresses 4 is provided on the network and this also stores data linking the public address to the addresses of the user's two or more communication devices 10. Communications addressed to the public address are directed to at least one of the two or more communication devices. Communications originating from any one of the user's communication devices have data inserted into them to identify the communication as originating from the user's public address.

Description

MOBILE COMMUNICATION SYSTEM FOR MORE THAN ONE

MOBILE DEVICE ON A SINGLE NUMBER

Field of the Invention

This invention relates to a system for enabling a subscriber to a mobile communication system to use two or more handsets on other receiving devices on the same number.

Background to the Invention

A number of mobile networks currently offer services which enable subscribers to use two or more handsets on the same number. These are often referred to as Multi-SIM services.

There are a number of reasons for subscribers to have more than one device on the same number. For example * Many car phones require a separate SIM and without this functionality a car phone would have a different number to a user's normal phone.

* Some users have different handsets for e.g. business and personal use, but may wish to use the same number for both.

* Some users have data cards for laptop computers. These require a separate SIM.

There are a number of difficulties with Multi-SIM systems, none of which has been completely satisfactorily addressed. For example, if a Multi-SIM user has two devices, each requiring a SIM card, for these to operate on the same number each will require the same Mobile Station ISDN (MSISDN) calling line identification number (CLI). Whilst it is possible to make calls or texts from both handsets, problems arise when calls or texts are received from other users.

Some systems enable a user to define a handset as a master, and to have all incoming communications arrive at that handset only. This may be achieved by the user defining a handset as the master by inputting a Unstructured Supplementary Service Data (USSD) code to it, which is then sent to the network. Master status can also be controlled by e.g. designating the most recently activated handset or the most recently used handset as the master.

Such systems require the user to remember the handset which is designated as the master. This may result in him inadvertently carrying the slave handset with him, which would result in him being unable to receive calls or texts, and he Other systems enable calls to arrive on both handsets. Answering a call on one handset, clears it from the other. This is more difficult to implement with text (SMS) as there is no mechanism available in current networks to sent texts to two or more destinations.

Whichever model is implemented, it will need to use different SIMs with different IMSIs but the same voice and text MSISDN for each handset. Each SIM card must have a unique IMSI (international Mobile Subscriber Identity), whereas MSISDNs do not have to be unique. Indeed multiple MSISDNs are commonly assigned to a subscription for different bearer services e.g. voice, text, data. The network will retain a separate record for each SIM in its Home Location Register (HLR) function. Some networks may need to store the data for each member of a MultiSIM group in a separate HLR to avoid internal HLR conflicts between MSISDNs. In a master/slave setup, the network will need to maintain the master/slave status of each Multi-SIM, thereby requiring additional processing in the network.

In European patent application no. EP-A-1 145577 there is described a system in which connection is made via a data network to various data hosts or applications within a mobile network. It is possible to send messages to them or receive messages from them. This is achieved by making connection via a virtual mobile number associated with the data network.

EP1 586207 shows a system in which a text message generated in a mobile network is delivered as an email to a data network from a telecommunications system. The data network has associated with it in the mobile communications network a virtual mobile number. This is the number the sender dials to send a message to the data network. At an email gateway, the virtual mobile number is mapped to an email address and the message is sent on to that address.

Summary of the Invention

Preferred embodiments of the present invention provide a system and method for enabling a user to have Multi-SIM functionality using linked but otherwise ordinary SIMs. These do not need to have the same MSISDN number and do not need to load subscription data onto different HLRs. This is achieved in preferred embodiments of the invention by linking two or more SIMs to a virtual mobile number. This number is preferably used as a user's CLI in all communications.

Preferably there is provided a mobile communication system in which a user may have two or more communication devices associated with a single public address, comprising means for storing a user's public address on the network and for storing data linking the public address to addresses of the user's two or more communication devices, means for directing communications addressed to the user's public address to at least one of the two or more communication devices, and wherein the addresses of the two or more communication devices are different to the user's public address.

Preferably a system includes means for inserting data into a communication originating from any one of a user's communication devices to identify that communication as originating from the user's public address.

The communication may be a voice call, a text message, a multimedia message, or a video message.

Brief Description of the Drawings

A preferred embodiment of the invention will now be described in detail by way of example with reference to the accompanying drawings in which: Figure 1 shows a schematic diagram of the arrangement in a network for sending voice calls in an embodiment of the invention; Figure 2 shows the arrangement in a network for sending SMS messages in an embodiment of the invention; Figure 3 shows a schematic diagram of the arrangement by which a CLI of a SIM can be spoofed to match the assigned virtual mobile number; and Figure 4 shows a schematic diagram of the sending of a text message to a virtual mobile number.

We will consider here a straighiforward embodiment of the invention in which there are two mobile SIMs which are referenced by MSISDN A and IMSI A, and MISISDN B and IMSI B. These two mobile SIMs are linked by a virtual mobile MSISDN V which is stored in a home location register (HLR) of a subscriber's home network. This virtual mobile number V is the public number of a subscriber. The system is configured so that the user can have either a master/slave configuration as discussed above where he can select which handset will receive incoming communications addressed to the virtual mobile number, or a parallel reception model where communications to the virtual mobile number are received on both handsets. Preferably the system is configured to permit the system to operate independently for text, voice and other media such as data services.

Because a virtual number is used there is no need for any location information to be tracked for V and hence no need for signalling functions required to keep location information up to date for V. This information is required for A and B. Also, there is no requirement for any forwarding information to be associated with the virtual number. Location and tracking information only applies to the real numbers A and B of the two SIMS. As a result, the HLR function for a virtual number is relatively simple and can be implemented without all the functionality associated with a normal HLR and is preferably implemented with a separate HLR function in a network to those HLR functions handling normal subscriber numbers. What the virtual number HLR needs to do is to act as a proxy for calls to the virtual number which will substitute the numbers of SIM card A or B and will forward signalling messages relating to V to the correct HLR, and will cause a communication sent to the virtual number to be delivered to the relevant device A orB.

A first embodiment of the invention is now described in which a master/slave arrangement is set up in a GSM mobile communications network. Comparable implementations are envisaged for networks other than GSM. As discussed above, a master/slave service enables a user to select the handset which will receive incoming calls and messages. An embodiment of a system with which this is implemented is shown in figure 1 for voice calls. In this, a gateway mobile switching centre (GMSC) 2 in the home network of a subscriber to a virtual number receives a call via the GSM network, either originating in the same network as the GMSC 2 or from a different network. The call is addressed to a virtual number. The GMSC then sends a send routing information (SRI) request to the HLR function 4 associated with the mobile number. The SRI request is received at an SMS router 6 which in practice includes the virtual mobile HLR 4.

This Router 6 translates the virtual mobile address V into the address for A (which is currently designated as the master MSISDN) and forwards the SRI message to the HLR 8 with which A is registered. The HLR 8 with which A is registered stores details of A's current location as it would do for any other mobile number registered with it, and uses this to obtain a roaming number of the corresponding VMSC where A is currently located. A response containing a roaming number for call A is returned to the GMSC and a call is put through to A. Figure 2 shows an arrangement for text messaging to a virtual number. A text message addressed to V is stored in a Short Message Centre (SMSC) 12 of a sender's network. This SMSC 12 then sends a send routing information for short message (SRI SM) request via a router 14 to a virtual mobile HLR 16 in V's home network. The SMS router identifies A as the current master corresponding to V, and looks up A's details. This returns the VMSC address for A, where A is currently set as the master by the subscriber to V. The router 14 then passes an IMSI and VMSC address for A to the SMSC 12 which in turn sends the text to A in the normal manner. If B were set as master then the IMSI and VMSC address retrieved from the HLR 18 would be those of B. Multimedia messages (MMS) notifications operate in a similar manner to the normal SMS messages discussed above in relation to figure 2. The only difference is that it is an MMSC rather than an SMSC which sends the SRI_SM.

The remainder of the process is the same as for SMS messages.

The handsets A and B which contain the SIMs linked to the virtual number V are able to make communications in the normal way, irrespective of which is designated master and which is designated slave. However, recipients of communications from A or B should preferably see these communications as originating from the virtual number V. Therefore the CLI data sent with calls from A or B has to be altered to make it appear to a recipient as if the communication originated with V. The system could be configured to enable communications to appear to come from A or B but this would bypass any master/slave connection made by the subscriber to V. It may also cause billing problems since it is more straightforward for all calls to appear to be originated from V and therefore to be charged to an account associated with the virtual mobile number.

Whenever a subscriber moves to a location served by a different visitor location register VLR, his registration is handed over to the new VLR. The new VLR sends a MAP Location Update message to the subscriber's HLR, which holds the subscriber's subscription and location information. The HLR then updates a copy of certain parts of the subscriber's subscription information held on the VLR where the subscriber is currently registered by sending the relevant information to the VLR. This copy of the subscription information is also updated whenever the subscriber changes his supplementary service settings, such as his call forwarding parameters. The VLR is updated using a MAP Insert Subscriber Data message sent from the HLR.

One of the data items held in the VLR is the subscriber's MSISDN, which is also known as his CLI when presented to another party as part of a communication.

This MSISDN is not used in any signalling over the radio interface to or from the handset. Whenever a user initiates a communication, the handset is identified by its lMSl, (actually a temporary alias thereof), and the user's CLI is only attached to the communication after it reaches the MSC to which the subscriber's VLR is attached.

In order to make communications from A or B appear to come from V, it is necessary to spoof the CLI stored in the visitor location registers (VLR) with which A and B are registered. This is illustrated with reference to figure 3. In this, a voice communication from A is routed to a visited mobile switching centre (VMSC). This is the VMSC associated with A's current location. A is registered with a VLR 22 coupled to the MSC 20.

Figure 3 shows how a call from A will have the CLI data of V inserted in A's CLI data.

The device A is registered with a home network 28 but is actually present in a foreign network. It is therefore registered with a visitor location register 22 via a VMSC 20. When a call from A reaches the VMSC 20, the CLI data is attached to the communication. In the case of A or B, the CLI data is a virtual number V, which is of course the public number associated with A and B. Given the above, the master copy of A's MSISDN (actually his voice and text MSISDN, he may have other MSISDNs for fax and data) is held in his HLR. A copy of this MSISDN, plus other data such as divert settings, is sent to his current VLR in response to a MAP Location Update message from the VLR to A's HLR 26 (which can be periodic, or whenever he moves location area) or in response to a change in service settings. The VLR's copy of the MSISDN is attached to communications initiated from A, after they reach the first MSC. Calls are then routed as normal to their destination, which maybe via an MSC 30 in the home network.

Hence in order to spoof the A MSISDN, so that it shows up as V on the recipient's phone, the system has to modify the behaviour of the MAP Insert Subscriber Data message between the HLR and the VLR so that the VLR's copy of the MSISDN says V instead of A. This can be done by: 1. modifying the HLR's behaviour to put V instead of A into the message (this implies that the HLR must store both V and A, and be aware of this application, or 2. leaving the HLR alone and intercepting any MAP Insert Subscriber Data for A and substituting V for A in the appropriate data field.

Option 2 above could be performed in the home network, which will be the network with the HLR for V. A second embodiment of the invention concerns an arrangement in which communications are duplicated to A and B rather than operating in a master/slave fashion. Further functionality has to be added to the system in order to implement this.

In the case of text messages, the operations which take place are illustrated in Figure 4. In this, the sender X 40 is currently not present in his home network 42.

If he wishes to send a text and transmits this to the VMSC 41 in the network where he currently is. This mobile originated message is transmitted to an SMSC 44 in the sender's home network. The message is addressed to a virtual mobile number, this virtual mobile number being the public number for a user with Multi-SIMS. The SMSC 44 sends an SRI_SM routing request to the HLR 46 in the recipient's home network. This is the HLR which stores the virtual number. This responds to the SRI_SM routing request by sending to the SMSC 44 the address of an SMS Router 48 in the recipient's home network 50. This causes the SMSC 44 in the sender's home network 42 to send a Mobile Terminated (MT) message to the SMS Router 48 in the recipient's home network 50.

On receipt of the MT message, the SMS Router 48 sends an SRI_SM routing request for B to the HLR 46. B is one of the SIMS attached to the virtual number to which the message is addressed. In this example, the HLR 46 is the same HLR as stores the virtual mobile number but may of course be a separate HLR as has been discussed above. In response to receipt of the SLR_SM routing request for B, the HLR 46 returns as a response the visited message centre (VMSC) 52 where B currently is. On receipt of this data the SMS Router 48 sends the MT message to the VMSC 52 in which transmits the message on to B 54.

The SMS router then repeats these steps to send the message to all the Multi-SIMS associated with the virtual number V then takes place. Therefore, if there are two Multi-SIMS A and B, the process will take place for A and B. If there are additional Multi-SIMS C, D etc, then the process will take place for them as well.

The effect is to send the text message to all the devices.

When text messages are sent from Multi-SIMS, the CLI data is spoofed in a manner similar to that described in relation to voice calls above.

The modification of voice calls is similar. A call to a virtual mobile number is sent to a GMSC in the sender's network. The GMSC then sends an SRI request directly to the HLR for V which returns dialable addresses for voice services equipment. The GMSC only expects to make one call. The call is therefore split into two calls using suitable voice services equipment. The two calls can then be made to A and B simultaneously from the voice services equipment until one answers. If neither answers then both calls are cleared and whatever forwarding rules have been put in place are followed.

The system has been described above in relation to Multi-SIMs placed in handsets of two or more devices assigned to a user. These devices can include a data card for a lap-top computer, and any other device which has a SIM associated with it.

As has been discussed above, it is necessary to spoof the CLI for Multi-SIM devices to show the virtual number to a recipient.

The association of two or more Multi-SIM numbers with a virtual number in a network enables a subscriber to have a single number which he can publicise to others. Preferably if he already has a well-known number he is able change this to a virtual number and obtain new numbers for the Multi-SIM cards which he needs for his multiple devices.

An appropriate software modification may be made to existing networks to enable the functionality described above to be implemented. Thus a computer program can be supplied with the appropriate modifications.

The system has been described with reference to voice and text calls. It can, however, also be applied to video calls and other multimedia messages.

Claims

CLAIMS

1. A mobile communication system in which a user may have two or more communication devices associated with a single public address comprising means for storing a user's public address on the network and for storing data linking the public address to addresses of the user's two or more communication devices, means for directing communications addressed to the user's public address to at least one of the two or more communication devices, and wherein the addresses of the two or more communication devices are different to the user's public address.

2. A system according to claim 1 including means for inserting data into a communication originating from any one of a user's communication devices to identify said communication as originating from the user's public address.

3. A mobile communication system according to claim 1 or 2 in which the communication is a voice call.

4. A mobile communication system according to claim I or 2 in which the communication is a text message.

5. A mobile communication system according to any previous claims in which the means for inserting data into a communication comprises means for inserting calling line identification data (CLI) into a communication.

6. A mobile communication system according to claim 4 in which the means for inserting CLI data inserts CLI data relating to a user's public number.

7. A mobile communication system according to claim I in which the means for directing communications to a communication device directs communications to a device designated as a master device.

8. A mobile communication system according to claim 1 or 6 in which the means for directing communications comprises means to retrieve an address of one of a user's communication devices in response to a communication addressed to a user's public number.

9. A method for operating a communication system in which a user has two or more communication devices, each with different addresses comprising the step of storing a public address for the user with data linking the public address to the addresses of the user's two or more devices, directing communications addressed to the public address to at least one of the two or more communication devices, and wherein the addresses of the user's two or more communication devices are different to the user's public address.

10. A method according to claim 9 including the step of inserting data into a communication originating from any of one of a user's communication devices to identify said communication as originating from the user's public address.

11. A method according to claim 9 in which the communication is a voice call.

12. A method according to claim 9 in which the communication is a text message.

13. A method according to claim 9 in which the step of inserting data into a communication compromises inserting CLI data relating to a user's public number.

14. A method according to claim 9 in which the step of directing communications directs communications to a communication device designated as a master device.

15. A method according to claim 9 or 14 in which the step of directing communications comprises retrieving an address of one of a user's devices from a store in response to a communication addressed to a user's public address.

16. A mobile communication system substantially as herein described with reference to the accompanying drawings.

17. A method for operating a mobile communication system substantially as herein described.