WO2009065195A1

WO2009065195A1 - Mobile roaming call-back method

Info

Publication number: WO2009065195A1
Application number: PCT/BG2008/000023
Authority: WO
Inventors: Victor Eli Francess; Kaloyan Lyubomirov Georgiev
Original assignee: All Telecoms Jsc
Priority date: 2007-11-23
Filing date: 2008-11-19
Publication date: 2009-05-28
Also published as: BG110004A

Abstract

The MT (10) in roaming submits a signaling message (20) to CCS (30), which is connected to HNS (40) and TE (50) of the called party, which accepts the call. User A initiates a call (100) to user B. Then MT submits a message to CCS. During the signalization MT or CCS temporary suspends the call. Then the CCS decides upon its predefined rules or a real-time interaction with the HNS how to respond. The possible responses are - making a call-back (104) to MT, as it is possible (110) the CCS to inform MT for its decision via signaling, then the CCS establishes a call (108) to MT and then establishes a call (115) to TE. In (113) MT receives voice information by the CCS while the connection with TE is being established and in (116) TE accepts the call. The CCS establishes the connection (117) between MT and TE.

Description

MOBILE ROAMING CALL-BACK METHOD

Field of Invention

The invention is in the field of mobile communications and services and affects a method of originating mobile calls while in roaming.

Background of the technology

There is a known solution (I)₇ in which are described a system and a method for connecting calls in telecommunication networks referring to users of prepaid cards, that are using roaming(foreign mobile network). When a user is in roaming he can activate the system with unstructured supplementary service data (USSD), dialing a short code, followed by the number he wishes to dial. Then the prepaid account of the user is monitored in real time (until the account is completely spent). The main feature of this solution is the connection of the user, which initiates the call, with the one that receives the call, It is achieved by using databases and computers without making changes in the existing infrastructure of the network and the phone.

The flaws of this solution are that the users are forced to memorize short codes, needed for the use of roaming. Also, the users are unable to use their address book. Another flaw of the proposed solution is that its functionality is bonded with the presence and functioning of unstructured supplementary service data (USSD).

Technical nature of the invention

The mission of the invention is to deliver a method of accessing the mobile services in roaming for all the mobile users and also for the automatic transformation of the outgoing roaming calls into incoming calls.

The mission is achieved by a method for building mobile roaming calls, in which a call control server is connected with a home network server or a set of servers, which belong to the user's home mobile network. The Terminal Equipment (TE) of user B (the receiving side) accepts the call. The user A with a Mobile Terminal(MT) in roaming initiates a call to user B with TE, using the. keypad of his MT or choosing from the address book or call register of the MT. Next, the MT of user A sends a signal message to the call control server, which can be done in several ways. During the signalization the MT of user A or the call control server intercepts and temporary suspends the call. In some cases the regular mobile signaling (SS7 or CAMEL signaling) is being used and interpreted as a request for transformation of outgoing roaming calls into incoming calls (call-back) to the call control server. In other cases the request for transformation of the outgoing roaming calls into incoming calls (call-back) is sent by USSD, SMS, GPRS, DTMF or other methods. The call request is accepted by the call control server as a request for call-back to the MT of user A.

Then the call control server decides upon its predefined rules or upon real-time interaction with a home network server how to respond. The possible responses are: making a call-back call to the MT of user A, standard call or rejecting the call.

Then the call control server decides to make a call-back to the MT of user A. There is a way for the call control server to inform the MT of user A for its decision through the signalization by showing the message on the display of the MT of user A.

Then the call control server makes a call to the MT of user A, after which makes a call to the TE of user B. The MT of user A accepts the call automatically or manually.

There is a way for the MT of user A to receive voice information from the call control server, while making the connection with the TE of user B. Then the TE of user B accepts the call.

The call control server makes a connection between the MT of user A and the TE of user B. It is possible first to make the call to the TE of user B and then to the MT of user A.

When the user A is in roaming and is calling user B, the call takes place when user A with MT in roaming originates a call to user B with TE, using the keypad of the MT of user A or choosing from the address book or the call register in the MT of user A. The MT of user A submits a signaling message to the call control server via home network gateway (HNG) by the normal mobile signaling (SS7, CAMEL, etc.). Then the normal call request is used and interpreted as a call-back request message to the call control server. The call control server decides upon its predefined rules or upon a real-time interaction with home network server, how to response. This is applicable in case that the home network operator of user A does not support USSD or CAMEL and when user B is a subscriber of the home network of user A or user B is currently in roaming of the home network of user A. The invention can be integrated to GSM, UMTS or CDMA networks. In this case the invention is accomplished through a home network gateway, used for signaling exchange with a call control server. The signaling exchange is a standard roaming signalization - ISUP&MAP&CAMEL.

When user A is in roaming and calls user B, the call is also realized when user A with MT initiates a call to user B with TE by using the keypad of the MT of user A, chooses from the address book or the call register of the MT of user A, etc. Then the MT of user A submits a signaling message to the call control server through a home network server by sending a USSD message. During the signalization, the MT of user A or the call control server temporary suspends the call. This is followed by an action, in which the call request is sent as a USSD message. Reaching the call control server the message is interpreted as a request for a callback to the MT of user A. In this case the invention is accomplished using USSD messages. It is applicable in case that the home network of the mobile operator of user A, which initiates a call in roaming, supports USSD message exchange, and also - to have the possibility for USSD message exchange in the visited by user A mobile network. Meanwhile the invention accomplishment does not put any restrictions for user B.

The signalization is USSD messages and standard mobile signaiization. The home network server is able to exchange USSD messages (a set of USSD gateway and data base that the call control server interacts with).

When user A is in roaming and calls user B, the call is also realized when user A with MT initiates a call to user B with TE by using the keypad of the MT of user A, chooses from the address book or the call register of the MT of user A, etc. Then the MT of user A submits a signaling message to the call control server through the home network server, using standard mobile signalization (SS7, CAMEL, etc.). In this case the call request is used and interpreted to the call control server as a request for call-back to the MT of user A. In this case the invention is accomplished using CAMEL technology and is applicable in case that the visited by user A, which initiates the roaming call, network supports CAMEL and in case the HLR in the home mobile network of user A supports CSI. At the same time the invention accomplishment does not put any restrictions for user B. The home network server is able to exchange CAMEL messages (a set of SCP and database that the call control server interacts with).

The advantages of the solution are, that the users can use freely their address book and don't have to remember short codes, to initiate calls. Another advantage of the invention is, that by using it the change in the usual user experience is very little, if there is any. The invention is applicable not only for prepaid users, but also for postpaid users. Also, the presence and function of USSD are not necessary for the functioning of the invention.

Description of the embedded figures

Figure 1 shows the network architecture of an embodiment of the invention

Figure 2 shows a block diagram of the processes exchanged within the communication system of the invention

Figure 3 shows a Home Network Gateway implementation of the invention

Figure 4 shows a block diagram of the processes exchanged within the communication system for the Network Gateway implementation of the invention

Figure 5 shows an implementation of the invention using USSD

Figure 6 shows a block diagram of the processes exchanged within the communication system for the implementation using USSD

Figure 7 shows a CAMEL implementation of the invention

Figure 8 shows a block diagram of the processes exchanged within the communication system for the CAMEL implementation Cases of embodiment of the invention

One case of embodiment of the invention is shown on figures 1 and 2. In this case MT 10 is the mobile equipment (usually a handset) of the roaming user (user A), that initiates the call - calling party that sends the signaling 20 to the CCS 30. The last is the part of the invention, which applies the logic, makes the call-back and connects the calls. The CCS 30 is connected to a Home Network Server (HNS) 40 or a set of servers, belonging to the home network of the user. The TE 50 of user B (called party) accepts the call.

The MT(IO) submits a signaling message 20 to CCS 30 possible by various means, incl. the normal mobile signaling (SS7, CAMEL, etc.). During the signaling 20 the MT 10 or the CCS 30 may temporarily suspend the call 101. In some cases the normal call request (SS7 or CAMEL signaling) is used and interpreted as a call-back request message to the CCS(30) 103 and in other cases the call-back request message is sent by USSD, SMS, GPRS, DTMF or other means 102. Optionally, there is a hardware or software logic within the MT(IO) incl, on the SIM card (if any) inside the MT(IO) to manage the signaling process.

The CCS 30 receives a signaling message from MT(IO) with a request for a call-back call to TE(50) 104.

The CCS 30 decides upon its predefined rules or upon real-time interaction with a Home Network Server 40 how to respond 104,105. The possible responses are: call-back call 104 to MT 10, standard call 105 or rejecting the call 107.

CCS(30) decides to make a call-back call 108. It may optionally inform MT(IO) via signaling(20) for its decision and show an informative message on MT(IO) display 110.

CCS(30) establishes a call 108 to MT 10, then establishes a call 115 to TE 50. In this case MT 10 accepts the call automatically 112 or manually 111. It is optional the call to TE 50 to be established first, and then the call to MT 10.

The CCS 30 may optionally play voice information (113) to MT (10) while waiting for TE (50) to answer. Then the TE 50 accepts the call (116).

The CCS (30) connects the call between MT(IO) and TE(50) 117.

Another case of embodiment of the invention is by using Home Network Gateway (60) and is shown on figures 3 and 4. This embodiment of the invention is applicable in case the Home Operator's Network of the calling party (user A) support neither USSD nor CAMEL. It is applicable in case the called party (user B) is a subscriber of the HPLMN of the calling party (user A) or the called party (user B) is a subscriber currently roaming in HPLMN of the calling party (user A). The invention could be integrated into GSM, UMTS or CDMA networks. The Home Network Gateway(60) is used to relay signa!ing(20) to CCS(30). The signaling relay is a standard mobile signaling - ISUP&MAP&CAMEL.

When the user A is in roaming and calls user B his call is realized in the following way:

100) User A with MT(IO) originates a call to user B with TE(50) using the keypad, choosing a number from the address book, from the call register in his MT(IO), etc.

103) The MT(IO) submits a signaling message(20) to CCS(30) via HNS(42) by the normal mobile signaling (SS7, CAMEL, etc.)

104) In this case the normal call request (SS7 or CAMEL signaling) is used and interpreted as a call-back request message to the CCS(SO)

104 and 105) The CCS (30) decides upon its predefined rules or upon real-time interaction with a Home Network Server (40) how to respond. Further on the process continue exactly as described in the first case of embodiment of the invention.

The third case of implementation of the invention is using USSD messaging and is shown on figures 5 and 6. This embodiment of the invention is applicable in case the Home Operator's Network of the calling party (user A) supports USSD messaging. It is applicable in case the VPLMN also supports USSD messaging exchange. This embodiment of the invention does not put any limitations towards user B.

USSD messaging 20 is a standard mobile signaling. The Home Network Server (41), has a USSD processing capability (a set of USSD Gw and Data Base that CCS (30) interacts with).

101) The MT (10) submits a signaling message (20) to CCS(30) via HNS(41) by sending an USSD message. During the signaling (20) the MT (10) or the CCS(30) temporarily suspends the call.

104) In this case the call request is transformed and sent as USSD message 102. It is used and interpreted as a call-back request message to the CCS (30).

Further on the process continue exactly as described in the first case of embodiment of the invention.

Fourth case of implementation of the invention is by using CAMEL technology and is shown on figures 7 and 8. This embodiment of the invention is applicable in case VPLMN supports CAMEL and HLR supports CAMEL Subscriber Information (CSI). This embodiment of the invention does not put any limitations towards user B. The Home Network Server (42) has CAMEL processing capability (a set of SCP and Data Base that CCS (30) interacts with).

100) User A with MT (10) originates a call to user B with TE(50) using the keypad, choosing a number from the address book, from the call register in his MT(IO), etc.

103) MT (10) submits a signaling message (20) to CCS(30) via HNS(80) by the normal mobile signaling (SS7, CAMEL, etc.).

104) In this case the normal call request (SS7 or CAMEL signaling) is used and interpreted as a call-back request message to the CCS(30).

Application (utilization) of the invention

The implementation of the invention gives the users that initiate all kinds of roaming calls an automated process of converting the outgoing roaming calls into incoming calls (call-back) that doesn't lead to any major changes (if any) in the standard user behavior.

The invention is used as follows. There is a mobile user, which is in a foreign mobile network (roaming). The user chooses a number he wishes to call. If the mobile equipment of the user supports automatic response of an incoming call, then there is no change in the standard user behavior for that user while making the connection. In case the automatic response is not supported by the mobile equipment of the user, on the display of his mobile equipment is shown a text message, which informs the user that he will receive an incoming call he needs to accept. After the user accepts the call he is waiting for the called party to accept the placed call. In case the called party accepts the call, follows the conversation.

Literature:

1. US 7 181 210

Claims

Patent Claims

1. Method of building mobile roaming calls in which the calling party MT (10) in roaming sends signalization (20) to CCS (30), which is connected to HNS (40) or a set of servers, belonging to the home network of the user and TE (50) of user B (called party), which accepts the call characterized by that, that user A originates a call to user B with TE(50) using the keypad, choosing a number from the address book, from the call register in his MT(IO), etc., then in (103) the MT (10) sends a signaling message (20) to the CCS (30), during the signalization (20), in (101) the MT (10) or the CCS (30) temporarily suspends the call, in case (103) the regular mobile signaling (SS7 or CAMEL signaling) is being used and interpreted as a request for transformation of outgoing roaming calls into incoming calls (call-back) to the CCS (30), or in case (102) the request for transformation of the outgoing roaming calls into incoming calls (call-back) is sent by USSD, SMS, GPRS, DTMF or other methods, then the call request is used and interpreted as a call-back request message (104) to the CCS (30), then the CCS (30) decides upon its predefined, rules or upon real-time interaction with a home network server (40) how to respond as the possible responses are: making a call-back call (104) to MT (10), standard call (105) or rejecting the call(107), then the CCS (30) decides to make a call-back (108) to MT (10), as the CCS (30) may optionally inform MT(IO) via signaling(20) for its decision and show an informative message on MT(IO) display, then the CCS (30) decides to make a call-back call (108) to MT (10), then establishes a call (115) to TE (50), then follows (113) in which the MT (10) receives voice information from the CCS (30), while making the connection with the TE (50), then in (116) the TE (50) accepts the call, the CCS (30) establishes the connection (117) between MT (10) and TE (50).

2. A method, according to claim 1, described by that, that the CCS (30) establishes (108) a call to MMT (10), then establishes a call (115) to TE (50) and the MT (10) accepts the call automatically (112) or manually (111).

3. A method, according to claim 1, described by that, that when user A is in roaming and calls user B, the call is realized as user A originates a call to user B with TE(50) using the keypad, choosing a number from the address book, from the call register in his MT(IO), etc., then in (103) the MT (10) sends a signaling message (20) to the CCS (30) via home network gateway (60) by the normal mobile signaling (SS7, CAMEL, etc.), then (104) follows, in which the normal call request is used and interpreted as a call-back to MT (10) request message to the CCS (30), as in (104) and (105) the CCS (30) decides upon its predefined rules or upon a real-time interaction with home network server, how to response.

4. A method according to claims 1 and 3, described by that, that this is applicable in cases, in which the network of the home operator of the calling party (user A) does not support USSD or CAMEL and when the called party (user B) is a subscriber of the home network of the calling party (user A) or the called party (user B) is currently in roaming in the home network of the calling party (user A), as the invention can be integrated to GSM, UMTS or CDMA networks.

5. A method according to claims 1 and 3 described by that, that it is accomplished by using Home Network Gateway (60) to relay signaling(20) to CCS(30), as the signaling relay is a standard mobile signaling - ISUP&.MAP&CAMEL

6. A method according claim 1, described by that, that when user A is in roaming and calls user B, the call is realized, when user. A with MT(IO) originates a call to user B with TE(50) using the keypad, choosing a number from the address book, from the call register in his MT(IO), etc., then (101) the MT (10) submits a signaling message(20) to CCS(30) via HNS(41) by sending an USSD message, during the signaling(20) the MT(IO) or the CCS(30) temporarily suspends the call, followed by (104) where the call request is transformed and sent as USSD message 102, and getting to CCS (30) it is used and interpreted to the CCS (30) as a call-back request to MT (10) message.

7. A method according to claims 1 and 6, described by that, that it is applicable in case that the home network of the mobile operator of user A, which initiates a call in roaming, supports USSD message exchange, and also - to have the possibility for USSD message exchange in the visited by user A mobile network, meanwhile the invention accomplishment does not put any restrictions for user B, as the signalization (20) is USSD messages and standard mobile signalization and the home network server (41) is able to exchange USSD messages that the CCS (30) interacts with.

8. A method according to claim 1, described by that, that that when user A is in roaming and calls user B, the call is realized, when user A with MT(IO) originates a call to user B with TE(50) using the keypad, choosing a number from the address book, from the call register in his MT(IO), etc., then the MT(IO) submits a signaling message(20) to CCS(30) via HNS(42) by the normal mobile signaling (SS7, CAMEL, etc.), followed by (104), where the call request is transformed and sent as USSD message 102, and getting to CCS (30) it is used and interpreted to the CCS (30) as a call-back request to MT (10) message.

9. A method according to claims 1 and 8, described by that, that in case the invention is accomplished using CAMEL technology, it is applicable in case that the visited by user A, which initiates the roaming call, network supports CAMEL and in case the HLR in the home mobile network of user A supports CSI, as at the same time the invention accomplishment does not put any restrictions for user B, and the home network server (42) is able to exchange CAMEL messages.