GB2386300A

GB2386300A - Calling-party-pays option for calls to a roaming subscriber

Info

Publication number: GB2386300A
Application number: GB0305051A
Authority: GB
Inventors: Jeffrey Wilson
Original assignee: Intellprop Ltd
Current assignee: Intellprop Ltd
Priority date: 2002-03-05
Filing date: 2003-03-05
Publication date: 2003-09-10
Also published as: GB0205037D0; GB0305051D0

Abstract

A mobile telephone system determines whether or not the intended recipient of a call is a subscriber whose mobile terminal 34 is roaming outside its home network and if the intended recipient is roaming, connects the incoming call to the roaming recipient via the other network, subject to agreement that the calling party 22 will be billed for the full cost of the call. The cost of a call to a roaming subscriber is usually split between the caller and the called party. A subscriber registration means, such as a home location register (HLR) 28 may carry out the determination and selective call connection means, such as a service switching point (SSP) may connect the call. The roaming subscriber may be notified that an incoming call is free, e.g. via SMS, Class 0 SMS or voice call announcement. The service, provided by default or a pre-set request, may be limited to callers who are subscribers to the home network and callees who are pre-pay subscribers. By providing the option of allowing a caller to pay the full cost of a call to a roaming party, the called party avoids paying for unwanted calls but is able to receive important calls that might otherwise be diverted to voicemail or not connected due to an inability to check pre-payment credit while roaming.

Description

TELECOMMUNICATIONS SERVICES APPARATUS This invention concerns the field of telecommunications, and in particular relates to telecommunications services apparatus and methods for mobile telephone systems with specific reference to roaming.

Roaming refers to the capability of mobile subscribers to obtain service from a network other than the one to which they subscribe. When subscribers are roaming, incoming calls may be routed to them according to their current location, and they may also be able to make outgoing calls. The allowability of these operations depends on a number of factors, including their level of subscription, their current credit and the existence of roaming agreements between the relevant operators. Similar considerations apply to the availability of text messaging facilities to a roaming subscriber.

Mobile network tariffs, for example in the Global System for Mobile Communication (GSM), define the charges applied to the calling party, and in some cases to the called party, during a mobile telephone call. For example, in GSM, it is prevalent that the calling party pays the same tariff for a call to a particular called party regardless of where the called party is currently located, whether this be on the same network as the caller, a different network in the same country, or in a different country or continent.

Indeed the GSM specifications originally set out to protect the called party's privacy by not allowing the calling party to have access to any information regarding the called party's location, although this approach is being eroded by the development of location sensitive services and reverse charge services.

Clearly, when a called party is roaming, additional and even international call charges may be applicable to the call. It is prevalent in some countries for the called party to pay the additional charges while he is roaming. For example, subscribers A and B both subscribe to network C; subscriber A is currently registered on his home network, while subscriber B is roaming in another country. When A calls B, A will normally pay the applicable mobile to mobile tariff for network C, and will remain unaware of

B's location. Meanwhile the international leg of the call from network C to B's current location is charged to B who is the called party.

This situation can be undesirable to B, since he may have little or no control over who calls him while he is roaming. He may not even be able to determine the caller or the tariff before answering as calling line identity (CLI) is not always passed through internationally, but he is nevertheless charged to receive the call. For pre-pay callers, i. e. those who pay for telephone service in advance instead of having a post-pay account and a regular bill from the network, it may be inconvenient for them to top up their pre-pay credit while roaming. For this and other reasons, pre-pay users are likely to be even more wary than contract customers about such uncontrolled payments for receiving calls whilst roaming. It is common for some mobile users to divert all voice calls to a mailbox while roaming to avoid these termination charges. Text message alerts from a voice-mail system may then be used to filter the desired from the undesired callers, giving the roaming user additional options for communication with certain callers. The caller however may be unable to make direct contact with the roamer, even in a case of urgency, and even if he is willing to pick up the cost of the whole call.

It is known that mobile telephone calls can be set up by outdialling to two parties from an equipment, and then connecting the two parties together. This operation may typically be initiated by one of the parties, commonly a roamer, sending an initiating command to his home network, for example by text messaging or unstructured supplementary service data (USSD) means. This technique has been used by some networks to provide a means for pre-pay roamers to initiate outgoing calls, which would otherwise have been disallowed due to the inability of a normal roaming call set-up technique to permit credit checking in advance of and during the call. Similar techniques can be used to allow roamers to access other services from their home networks, and the principles are described in UK Patent Application Serial No. 2 367 218 A.

It has previously been proposed that equipments such as transaction convertors may be capable of receiving instructions from other equipments, such as a home location register (HLR) or a service control point, and as a result may be capable of initiating an outgoing message to a mobile or fixed terminal, for example using text messaging or USSD techniques. This is described in UK Patent Application No. 0302110.2.

According to one aspect of the invention there is provided telecommunications services apparatus for use with a mobile telephone system which has a home network and allowing a subscriber having a mobile terminal associated with the home network to roam within another network, the apparatus comprising: subscriber registration means responsive to an incoming call to determine whether or not the intended called party's mobile terminal is roaming within another network; and selective call connection means, responsive to the subscriber registration means determining that the intended called party is roaming, to connect the incoming call to the called party's mobile terminal via the other network, such that, subject to agreement, the calling party may selectively be billed for the full cost of the call.

According to another aspect of the invention there is provided a telecommunications services method for a mobile telephone system having a home network and allowing a subscriber having a mobile terminal associated with the home network to roam within another network, the method comprising: determining by a subscriber registration means and in response to an incoming call whether or not the intended called party's mobile terminal is roaming within another network; and selectively connecting the incoming call, in response to the subscriber registration means determining that the intended called party is roaming, to the called party's mobile terminal via the other network, such that, subject to agreement, the calling party may selectively be billed for the full cost of the call.

Further aspects of the invention provide a computer program for carrying out the above method, and a storage medium on which such computer program is stored.

A preferred embodiment of the present invention addresses the problem of unwanted call charges for roamers. It applies to both pre-pay and contract customers, but a network is free to offer the solution only to selected customers or groups of customers.

The technique works by providing the means for the calling party to accede to paying for the whole call cost, thereby providing the capability for the roamer to receive a free call. Possibilities exist for the roamer to receive notification on a call by call basis of whether the call will be free or not before he accepts it, or for the roamer to set up his divert options such that only free calls are received whilst he is roaming.

It is assumed that in order to receive free calls, the roamer will be willing to disclose the fact that he may not be currently registered on his home network. His precise location is still private, and only his presence or absence on the home network may be deduced by callers.

The technique is also applicable in countries where the called party pays a charge to receive calls, even when he is not roaming. In this case, the option for the caller to pay for the entire call could be offered, giving a free-call option to the recipient.

One technique which can usefully be used in conjunction with embodiments of the present invention, but is not essential to its operation, is called SRI (Send Routing Information) aliasing. This permits network A to intercept routing requests to its HLR, which are a necessary part of call set-up from any subscriber to a subscriber of network A, and to respond to those routing requests in such a way that the call is routed via an equipment which can perform a particular function or service in relation to the call. The call is subsequently routed to subscriber A. The routing via the said equipment permits additional or alternative operations to be performed during the call set-up or progress, including operations which can implement the present invention.

SRI aliasing is described in International Patent Application No. PCT/GB02/05378.

Embodiments of the invention permit a first subscriber of Network A to call a second subscriber of Network A while the second subscriber is roaming, and for the first subscriber to pay for the entire call cost. The call is then free for the second subscriber.

The service may be arranged to be activated in several different ways according to the desired implementation. For example, the second subscriber may elect to activate the service either on demand, or by default whenever he is roaming. The second subscriber may be presented with only free calls whilst roaming, or may be presented with all calls and an indication of whether a given call is free or charged. Other options are possible. In the case where the second subscriber, who is roaming, is notified of the opportunity to receive a free-of-charge incoming call, he is then able to take an action to accept the call, or to accept the call by default according to the implementation. A call may then be established by outdial to the called party from an equipment such as a Service Switching Point (SSP), and by subsequent connection of the two parties. An SSP is a telephony device that can originate and switch telephone calls. The technique may also be made available to a first subscriber from a different network ; however, in this case, billing issues are more difficult.

Significant features of embodiments of the invention are as follows- * The roamer is able to accept certain calls whilst roaming without being charged. This may be of benefit for example to parents who may be happy to pick up the cost of calls to children who are roaming with pre-pay telephones to ensure contactability. It may also be of benefit to any roamer who would otherwise divert all of their calls whilst roaming in order to avoid the call- termination charges.

The implementation may be set up so that either the roamer is notified on a call by call basis whether the call will be free, or every call to the roamer is a free call and other calls are diverted. In both cases the roamer has the option to accept or reject the call.

In standard networks, outgoing calls made by a roamer to an equipment in the home network may arrive without CLI, dependent on the features and characteristics of the networks involved in the call. Even if permitted by the network, use of an outgoing call by the roamer would therefore have to employ additional security steps such as PIN entry in order to identify and validate the caller prior to completing any connection. In the context of establishing of a person-to-person call between the roamer and a party who has previously

notified the roamer that they wish to set up a reverse-charged call, an outgoing call made by the roamer is therefore not an attractive option. The present technique can avoid this problem by the option of using a notification message followed by the opportunity for the roamer to use USSD as the means of acceptance of the call. USSD delivery always carries the identity of the sender's SIM, so additional security checks are not required.

. The notification message may be delivered by a text message. The text message may carry the identity of the call originator, thereby avoiding any problems due to possible loss of CLI during an international connection.

'The notification message may carry simple instructions as to how to accept the call, thereby avoiding the need for the user to read any manuals or by informed in advance of the operation of the service.

The notification may be sent by Class 0 SMS, a feature of GSM whereby the message is displayed immediately on the screen of a mobile terminal without

any user intervention. For example the message could read something like :

FREECALL frm 447700123456 Send *123# to accept.

Only the first part of the message may be displayed on some terminals, with the remainder accessible by scrolling down.

Alternatively the notification could be sent using USSD.

The invention will now be described by way of example with reference to the accompanying single figure drawing which shows a block diagram of telecommunications networks allowing roaming according to embodiments of the invention.

Referring to the drawing, a GSM Home Network includes a mobile switching centre (MSC) 20 which can communicate with a mobile terminal 22. The MSC 20 also communicates with a service switching point (SSP) 24 and with an SMS Router (SMSR) 26 which can be implemented by a transaction converter such as that manufactured by Telsis (RTM) Limited. The Home Network also includes a home location register (HLR) 28 and a further MSC 30 for communication with other networks.

The drawing also shows an Other Network including an MSC 32 which can communicate with another mobile terminal 34, and also with the Home Network.

The steps involved in setting up a call to a roamer may be characterised as follows.

USSD is used for the called party's response in this example; however, other techniques are possible. The initiating caller wishes to contact the roamer and may or may not be aware of the latter's location. In order to contact the roamer, it is assumed that the caller is willing to pay for the entire cost of the call, even if the called party is roaming.

In the drawing, steps 1 to 6 relate to the preferred embodiment, and additional steps 5a to 5e relate to an alternative embodiment described subsequently.

1. The'Free Incoming Calls Whilst Roaming'facility has been set up for the roaming subscriber of the Home Network. This may be done in a number of ways, but in the preferred embodiment, the roamer with the mobile terminal 34 has elected to receive only free calls whilst roaming, with other calls diverted to voice mail. The process begins by the initiating caller with the mobile terminal 22 accessing the service by dialling the called party's (roamer's) number in the normal way, achieving access to the MSC 20.

2. SRI aliasing is used in the Home Network to intercept all routing queries (SRIs) and responses for calls to the network's subscribers. These routing queries and responses are monitored by the transaction convertor or other equipment hereafter referred to as the SMS-R 26. SRI queries relating to calls

from subscribers of the Home Network to subscribers of the Home Network who are roaming are intercepted by the SMS-R 26, and the calls diverted via the SSP 24. Other calls are routed as normal.

3. The call arrives at the SSP 24.

4. Since the roaming subscriber (mobile terminal 34) has elected to receive only free calls whilst roaming, the SSP 24 now enters into a dialogue with the calling party (mobile terminal 22) in order to establish whether he is prepared to pay for the entire call cost. The SSP 24 plays an announcement to the caller informing him that he will be charged for the whole call and optionally inviting him to accept this charge by for example pressing a key.

5. If the calling party declines to pay for the whole call, then the call is routed to voice mail (not shown). If the calling party agrees to accept the cost of the call, then the caller is placed on hold while the remainder of the call set-up procedure is completed.

6. The SSP 24 dials out to the roamer with the mobile terminal 34, via the MSCs 30 and 32. If the roamer accepts the call, the SSP 24 joins the two parties together. If the roamer rejects or ignores the call, then transfer to voice mail is initiated in the normal way. If the originating caller (mobile terminal 22) is a pre-pay caller, then pre-pay credit may continue to be checked during the call in the normal way, causing call termination if credit runs out.

In the alternative embodiment, the following steps 5a to 5e are inserted between steps 5 and 6 in the preferred embodiment described above. This alternative presents the called party with a message in advance of arrival of the voice call, and this message may be used to inform the called party that the next call will be a free call.

5a. The SSP 24 generates a message to the SMS-R 26 requesting a free call to the called party. The SMS-R 26 already has the caller's CLI, the desired destination number and its international mobile subscriber identifier (IMSI), and preferably the VLR location of the destination telephone. If any of these items is not already known from the previously received SRI response, then the SMS-R 26 may obtain them via a separate query to the HLR 28.

5b. The SMS-R 26 then proceeds by sending a text message to the destination telephone (mobile terminal 34) in Class 0 format, via the MSCs 30 and 32.

This will appear on the destination terminal's screen and alert the user. The message can optionally indicate the initiator's CLI, the method for accepting the call, and the fact that the subsequent call will be free of charge. The SMS-R 26 then starts a timer, in order to implement a timeout period in which the recipient must respond in order to receive the call. The timeout period could be set to 40 seconds for example.

5c. The recipient responds by sending a USSD code (for example *123#) back indicating acceptance of the call. The USSD message arrives at the Home Network HLR 28, via the MSCs 32 and 30. The USSD code is chosen as one that will be passed back to the home network HLR 28 even though the called party (mobile terminal 34) may be roaming, as shown. A range of codes with this property is defined for GSM in the relevant 3GPP specifications.

5d. The HLR 28 recognises the USSD code and sends a message containing the recipient's CLI to the SMS-R 26. Alternatively, if the timeout period expires before the SMS-R 26 receives indication of the response, the call set-up will be abandoned.

5e. The SMS-R 26 matches the CLI with an outstanding free call request and informs the SSP 24 to complete the final call leg to the recipient, passing the VLR location information necessary for the SSP 24 to route the call.

As a further alternative, the roamer may elect to receive all calls, not just free calls whilst roaming. This would also be the default case for the roamer who had not specified an election. Under these circumstances the preferred embodiment would proceed in substantially the same manner as described above, except that if the calling party declined to accept the whole call cost, instead of the call going directly to voice mail the call would be presented to the roamer but without the preliminary notification message of a free call.

The roaming subscriber may have diverts or incoming call barring set up. The system could either be configured to override those options, delivering the alert and the call to

the subscriber regardless of these settings, or the system could be configured to comply with the settings. In the latter case, successful call termination might be prevented. A further alternative is to redefine the behaviour of one or more of the diverts, or to introduce a new call divert option, whereby the roamer could elect to only receive free calls whilst roaming, and to have all other calls diverted or barred.

One potential problem with the described model of an alert followed by acceptance and then a voice call is that the roamer may receive an unrelated call during the window of opportunity between the alert and the free call arrival. In this case the unwary recipient may unwittingly answer a charged call in the belief that it was the free call which he had accepted. A solution to this problem is to program the transaction convertor (SMS-R 26) to only permit one free-call set-up at a time to any given subscriber. SRI messages are sent to a network's HLR whenever a customer of that network is called by any subscriber on any network. SRIs which are related to destination numbers that already have a free-call set-up in progress can be responded to by the transaction convertor in the same way as if the destination phone were already busy. This will prevent any spurious calls from interfering with the free-call set-up.

Optionally, the announcement service of the SSP 24 could indicate to the initiating caller if the destination number requested was not currently roaming and that he should redial normally. The network operator may or may not wish to allow a free-torecipient service to be used wholly within the home network.

As an alternative to free calls, the recipient could be charged at some other rate or flat fee for receiving whilst roaming.

The alert message, which in the preferred embodiment is sent as Class 0 SMS, may be cancelled by sending a further Class 0 SMS to indicate to the recipient the expiry of the period of time during which he has the option to reply and accept the call. The second message could indicate that the recipient had received a'missed call from...'

In the event that the subscriber did not see the first alert, then the second message would still convey useful and correct information.

In the event that the recipient is busy when the initiator attempts the call set-up, the system could either inform the caller by audio message, or take him straight to the recipient's voice mail box. It is desirable that the transaction convertor should have access to information regarding the state of the recipient's phone prior to sending the first alert message. This status could be sent by the HLR 28 in its first message to the transaction convertor (SMS-R 26), or could be obtained by a subsequent query.

It would be possible to implement the invention without recourse to SRI aliasing by requiring the calling party to specify that he wished to initiate a call and pay for the entire call cost. This indication could be achieved for example by use of USSD, where the calling party sends a USSD message to the network containing the desired destination number, rather than dialling it directly. The HLR could then interpret this message as a free-call request, and inform the transaction convertor. The remainder of the call set-up would then proceed substantially as described above.

In so far as the embodiments of the invention described above may be implemented, at least in part, using software-controlled processing apparatus, it will be appreciated that a computer program providing such software control and a storage medium by which such a computer program is stored are envisaged as aspects of the invention.

GLOSSARY

CLI Calling Line Identity IMSI International Mobile Subscriber Identifier MAP Mobile Application Protocol MSISDN Mobile Station ISDN number SMS Short Message Service of the GSM mobile telephone system SSP Service Switching Point. Telephony equipment for switching, routing and originating voice calls, optionally supporting voice and DTMF interaction.

Transaction Equipment which filters and responds to certain signalling Convertor messages, and generates a free-call notification message to the roaming mobile USSD Unstructured Supplementary Service Data, a GSM Supplementary Service.

Claims

CLAIMS 1. Telecommunications services apparatus for use with a mobile telephone system which has a home network and allowing a subscriber having a mobile terminal associated with the home network to roam within another network, the apparatus comprising: subscriber registration means responsive to an incoming call to determine whether or not the intended called party's mobile terminal is roaming within another network; and selective call connection means, responsive to the subscriber registration means determining that the intended called party is roaming, to connect the incoming call to the called party's mobile terminal via the other network, such that, subject to agreement, the calling party may selectively be billed for the full cost of the call.
2. Apparatus according to claim 1, wherein the selective call connection means is selectively operable so as to be applicable only to a calling party who is a subscriber to that home network.
3. Apparatus according to claim 1 or claim 2, including notification means responsive to the selective call connection means to notify the roaming called party when the call is to be free.
4. Apparatus according to claim 3, wherein the notification means is operable to notify the called party by means of the Short Message Service (SMS).
5. Apparatus according to claim 4, wherein the notification is by Class 0 SMS wherein the message is displayed on the called party's mobile terminal without recipient intervention.

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6. Apparatus according to claim 3, wherein the notification means is operable to notify the called party by means of a voice call announcement.
7. Apparatus according to claim 6, wherein the voice call announcement is free.
8. Apparatus according to any one of the preceding claims, wherein the subscriber registration means is operable to restrict the free call service to pre-pay called party subscribers.
9. Apparatus according to any one of the preceding claims, wherein the selective call connection means is selectively operable to provide a calling subscriber with the free call service on demand by the calling subscriber.
10. Apparatus according to any one of the preceding claims, wherein the selective call connection means is selectively operable to provide a called subscriber with the free call service by default whenever the called subscriber is roaming.
11. Apparatus according to any one of the preceding claims, wherein the selective call connection means is selectively operable to provide a called subscriber with the free call service as a result of a pre-setting request from the called subscriber.
12. Apparatus according to claim 9, claim 10 or claim 11, wherein the selective call connection means is operable to provide a desired mode of free received call service upon receipt of an Unstructured Supplementary Service Data (USSD) signal from the subscriber.
13. Apparatus according to any one of the preceding claims, wherein the selective call connection means is operable, in response to receiving a call acceptance notification from the called party, to allow connection of the incoming call to the called party's mobile terminal.

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14. Apparatus according to claim 13, wherein the call acceptance notification is sent from the called party's mobile terminal as an Unstructured Supplementary Service Data (USSD) signal.
15. Telecommunications services apparatus substantially as herein described with reference to and as illustrated in the accompanying drawing.
16. A telecommunications services method for a mobile telephone system having a home network and allowing a subscriber having a mobile terminal associated with the home network to roam within another network, the method comprising: determining by a subscriber registration means and in response to an incoming call whether or not the intended called party's mobile terminal is roaming within another network; and selectively connecting the incoming call, in response to the subscriber registration means determining that the intended called party is roaming, to the called party's mobile terminal via the other network, such that, subject to agreement, the calling party may selectively be billed for the full cost of the call.
17. A method according to claim 16, wherein the selective call connection is arranged to be applicable only to a calling party who is a subscriber to that home network.
18. A method according to claim 16 or claim 17, wherein the roaming called party is notified when the call is to be free.
19. A method according to claim 18, wherein the roaming called party is notified by means of the Short Message Service (SMS).
20. A method according to claim 19, wherein the notification is by Class 0 SMS wherein the message is displayed on the called party's mobile terminal without recipient intervention.

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21. A method according to claim 18, wherein the called party is notified by means of a voice call announcement.
22. A method according to claim 21, wherein the voice call announcement is free.
23. A method according to any one of claims 16 to 22, wherein the free call service is restricted to pre-pay called party subscribers.
24. A method according to any one of claims 16 to 23, wherein the selective call connection provides a calling subscriber with the free call service on demand by the calling subscriber.
25. A method according to any one of claims 16 to 24, wherein the selective call connection provides a called subscriber with the free call service by default whenever the called subscriber is roaming.
26. A method according to any one of claims 16 to 25, wherein the selective call connection provides a called subscriber with the free call service as a result of a pre-setting request from the called subscriber.
27. A method according to claim 24, claim 25 or claim 26, wherein the selective call connection provides a desired mode of free received call service upon receipt of an Unstructured Supplementary Service Data (USSD) signal from the subscriber.
28. A method according to any one of claims 16 to 27, wherein the selective call connection allows connection of the incoming call to the called party's mobile terminal in response to receiving a call acceptance notification from the called party.

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29. A method according to claim 28, wherein the call acceptance notification is sent from the called party's mobile terminal as an Unstructured Supplementary Service Data (USSD) signal.
30. A telecommunications services method substantially as herein described with reference to and as illustrated in the accompanying drawing.
31. A computer program for implementing a method according to any one of claims 16 to 30.
32. A storage medium storing a computer program according to claim 31.