FI113136B - Investigation on accessibility of a terminal group - Google Patents

Description

1113136

ESTABLISHING THE AVAILABILITY OF A SET OF TERMINALS

Field of the Invention

The invention relates to the discovery of the target set of the terminal equipment of a mobile communication system. In particular, the invention relates to determining the reachability of a set of terminals within a defined area of a mobile communication system.

BACKGROUND ART As a result of the popularization of mobile stations, it has been found important to know the location of a mobile station with sufficient accuracy. To this end, numerous different positioning methods have been developed. One of the goals of the development work has been to meet the US authorities' requirement for a cellular network terminal location accuracy of 150 meters in the next few years. At present, a mobile station can be easily located with cell accuracy. More accurate positioning systems are generally based on sending messages from different base stations to the terminal, after which the time or signal strength of incoming messages is measured. Positioning often results in sufficient accuracy but loads the network causing 20 miles of traffic to the air interface. However, this has been considered acceptable, for example, in the case of positioning by the authorities. However, the location process is quite complex and results are • * slow, especially if there are more terminals to locate.

; ·· * For many reasons, including the above, • «· '· * | It is not appropriate to locate all the terminals belonging to a certain set. For example, there may be dozens or hundreds of employees in a company or government entity. Locating these can be an unnecessary burden on network resources, which can be costly for those who want to locate;

30 Another important question frequently asked about positioning * ·. ·. also related to discussions about the privacy of the user of the terminal. If, for example, • • • • • • • • • • • • • • • • • • • Why employees feel they can be located anywhere, anytime;

· ·: The reason behind the need for positioning is also often local. Prior art solutions do not have the ability to quickly find answers to question 2 113136, which users or which terminals are in the desired area. The mobile operator's information system, particularly some of its network elements such as the Visitor Location Register (VLR), could provide very detailed information such as the user's location area in the network area.

5 In practice, the Telecommunications Act prevents this by prohibiting disclosure to third parties. According to the current interpretation of the rules, it is not even possible to use only the information filtered by the operator from which the data outside the target set would have been filtered out.

BRIEF SUMMARY OF THE INVENTION

The object of the invention is to provide a solution which eliminates the above problems. This is achieved by using a method or system that meets independent requirements.

According to the invention, the reachability of a set of terminals is determined in the mobile communication system by first generating a query message containing the identifier for the desired set of terminals. Thereafter, the target area is determined from the mobile communication system and a query message is sent to the specified target area so that it can be received by several terminals in the said target area. At the receiving terminal, the sa-20 message is processed to determine whether the response '· *: message is sent from the terminal to the mobile communication system. Thus, in practice, it is checked whether the terminal device belongs to the set of terminals whose availability is determined. Ending. ·. telemis uses the identifier mentioned in the query message.

Finally, the availability of the desired terminals is determined on the basis of the response messages received in the system.

»· · ·

According to an embodiment of the invention, said query message is sent as a Cell Broadcast message. According to another embodiment of the invention, said response message is a short message message, a call request or a USSD message.

30 In the case where it is desired to keep the information desired, - '; to determine the feasibility of being unavailable to outsiders, the clear message can be encrypted using a key that is known only to a portion of the mobile network terminals, i.e., the set of terminals whose accessibility is sought in the defined area. The terminal then decrypts the • received 35 messages using a stored key for the terminal. Various target groups, such as the police, rescue and fire authorities, may also have multiple group-specific decryption keys in addition to the group-specific keys.

The identifier of the inquiry message sent to the area of the mobile network may refer to the entity whose accessibility is being attempted or to the entity trying to determine its availability. The identifier may also refer to the encryption key or call type used.

Further, the determination of the availability status of the set of terminals may be supplemented by locating the mobile stations transmitting the message using some method of locating the mobile communication system.

10

List of figures

The invention will now be described in more detail with reference to the following exemplary schematic diagrams, of which Figure 1 illustrates the architecture of a prior art cellular network capable of transmitting and locating cellular communications, Figure 2 illustrates an embodiment of the invention for transmitting messages to a desired network area, FIG. 4 illustrates the operation of the paging system illustrated in FIG. 2. in block diagram form, • k; * '** FIG. 5 illustrates an encryption key generating algorithm in a system according to the invention using encryption of messages to be transmitted to the area, FIG. 6 includes a block diagram of the received mobile message processing, and ·: ··: FIG. more specifically, the subscriber identity module '' on the mobile station: 30 application operation upon receipt of the message.

DETAILED DESCRIPTION OF THE INVENTION. ··: The idea of the invention is to determine the reachability of a set of terminals in a mobile communication system. Accessibility primarily refers to 4,113,136 information on whether the terminal is reachable or on, so that the mobile network can, if necessary, access the terminal.

State-of-the-art mobile communication systems, such as the GSM system 5 illustrated in its main network parts in Figure 1, generally contain various network elements which together form the operator's mobile network 100. Users have mobile network terminals 101, 102 that may communicate with the network. The connection is handled by the base stations 111, 112 such that the coverage areas of the base station transceiver units form cells, which further form the location areas. The base stations are controlled by the Base Station Controller BSC 121, which contains information about the base stations in the areas it manages and their location areas. The actual switch is the MSC (Mobile Switching Center) 131, which often also performs the functions of the Visitor Location Register (VLR). The VLR contains information about the terminals in the network area and the services subscribed to them. For example, the VLR contains information about the location area in which each mobile station accessible by the network is located. The actual subscriber data of the GSM network is located in the Home Location Register (HLR) 132. The HLR is usually the same and is located in the subscriber's home network, even if the subscriber is in a different operator network: · · The VLR, however, changes as needed. There are usually elements in the network: there are also elements for handling message traffic, such as short message-

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SMSC (Short Message Service Center) 141.

... For example, GSM networks and new terminals support Cell Broad-

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* ··· * 25 east messaging, which is described in more detail in ETSI (the

European Telecommucations Standards Institute) specification TS 23.041.

:. In practice, messaging is often implemented such that the Cell Broadcast Center CBC (122) includes information about the base stations of the network, or part of it, the BSC that controls them, and possibly also the base stations. 30 geographic location information. The Cell Broadcast message is sent to the selected '· * cells via the BSC so that it can be received by all mobile stations within the cell's range. Mobile devices generally have different ways of defining the channels to be tracked, such as criteria based on topics numbered per channel, language definitions 35 for incoming messages, or subject areas. Cell Broadcast messages contain a maximum of 15 pages, each containing up to 93 characters of information. The CBC system allows the transmission of a message to a desired geographical area by simply defining the content and delivery area of the message. The system handles the transmission of messages according to the area definition BSCs required. Generally, the message frequency is adjustable, in some embodiments the transmission interval is 5 4-1024 seconds .

The potential network-related positioning system 161 referred to above is often located so that it can determine the VLR used by the subscriber by sending a query to the HLR. The positioning system is used by sending a query containing the subscriber identifier. Based on the query, the location-10 system may further ask the subscriber's location area VLR. Thereafter, various measurement messages are generated, the form and purpose of which depend largely on the positioning method used. For example, the Enhanced-Observed Time Difference (E-OTD) method measures the time difference between messages between different base stations and the terminal.

15 In order to determine the availability of the set of terminals, the call system 271 shown in Figure 2 may be added to the state-of-the-art GSM system.

20 The paging system first defines a set of mobile stations *. system subscriber IDs. The subscriber IDs are generally associated with the terminals whose availability is to be ascertained, such that the subscriber ID is stored in the Subscriber Identity Module SIM. The subscriber * identity module, in turn, is connected to the terminal that the subscriber carries with him * · 25. The specified subscriber IDs are stored in the destination database 272.

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The target database may have several different sets of mobile subscriber - ..: identifiers, and the sets may also overlap.

The geographical area is then defined according to the prefix ··. * In Figure 3. The map of Figure 3 shows two restaurants 30 (RESTAURANT 1, RESTAURANT 2), an office (OFFICE) and a dormitory • *. (DORMITORY). In the example case, the clients of the security company include the two popular restaurants and the busy office. The company provides dormitory services to the security guards it employs. : · *: If there is a need for security services in an office in the night area, the problem underlying the invention 35 is to reach a security force close to the 113136 facility. Not all guards should be located because it is known that there are numerous of these two restaurants.

According to the invention, a map is defined on the map of the GIS system, whose coordinates (X1, Y1) and (X2, Y2) are provided to the CBC-5 system. The CBC system selects cells corresponding to the coordinates it retrieves from the base station network database 223 such that they cover a sufficiently defined area. In the example, these cells are cells 1-8 (CELL NUMBER 1-8). The CBC system may also include cell identifiers (Cell ID) consisting of a Cell Identity Unit Cl (Cell Identity), a Location Area Code (ID) 10, a Mobile Network Code (MNC) and a Mobile Country Code (MNC). In addition, the CBC system generally also contains information on the BSC controlling each base station, which in the example are two cells corresponding to a defined area, BSC ID = 5301 and BSC ID = 5302.

15 The operation of the system used to determine the reach of a set of terminals will be examined in more detail in connection with Figure 4. The group to be invited is first defined. This may include, for example, in the case of Figure 3, the code entered by the customer using the system, i.e., the security guard, "" Reach Turn 74-52 20 OFFICE ". The code may be entered, for example, by a mobile system terminal and sent as a text message to a server. The message is then routed from SMSC to the system based on the ID Reached there.

The system user interface can also be implemented using client • server technology, whereby the client company using the system Ί 25 has software in place to define the group to be called. Then you can -! * · · Select from the menu or press the "AIM" button and select the advanced items individually. The system can also be implemented through a web interface, whereby the client company has an Internet browser that connects to: · *: the server that uses the set of device availability discovery system 30. The embodiment chosen for the user interface is not a key element of the invention.

* · '; After the example security watchdog has sent a Reach For Shift message, the system determines in step 402 which mobile: ··: Network Subscriber Identity (MSISDN) set contains the selected RANGE. This information 35 can be entered into the system, for example, by means of a user interface for accessing the main set of devices with an Internet interface, 7 113136, where first the telephone numbers of all the staff are entered and then the turnovers of each guard.

After defining the reachability of the inviting set, the entity wishing to determine the reach of the set is to be defined. In the example above referring to Figure 3, the coordinates are already provided in the call given in SMS format. 74-52 refers to a coordinate system recognized by a customer and the reachability system. There are many possible ways of expressing coordinates, the simplest of which are, for example, 10 digits referring to a phone book map page or box. More advanced systems may also include map information in the GIS, whereby the calling party may, for example, select the area from which to seek accessibility. However, the system recognizes the desired area definition in step 404 and sends a request to the CBC system to select cells in the desired area. This is done in step 406.

15 An outgoing message will be labeled. In principle, the identifier to be attached can be simple, for example, the text Reach, which refers to all mobile stations that receive the message. In practice, however, a group-specific key is defined for the called group. This can advantageously be accomplished in connection with the definition of groups. In this case, 20 security business customers may be assigned a VARTIJA tag. The system selects and appends the identifier to the message in step 408. Thereafter, the message to be transmitted is created in step 410, which may include, for example, encrypting the identifier to be transmitted with the encryption key used. Follow-up messages will be sent.

In one embodiment of the invention, the group definition (step 402), the geographical area definition (step 404), the identifiers used (step 408) are performed before the messages are generated, i.e., before step 410. Only then is a request sent to the CBC (step 406) and actually transmitting from the mobile network to the selected area.

• (: After sending the availability clearance request to the CBC • ·! System, the system will wait for responses (step 414). If no responses are received within the specified time counter or until the service is • terminated, proceeding is completed (step 424). apparently is not in the defined area, in which case 8 113136 may, for example, notify the sender of the availability request that no replies have been received.

If answers are received, it is considered (step 416) whether the responding terminals need to be located to increase the availability information. This can be inferred, for example, that if the invitation code has nothing but a group and an area (LOCATE LINE 74-52), no positioning is performed. If the call code also contains a possible destination (OFFICE), the responding terminals are located. In one embodiment of the invention, in the service access code, the definition of an OFFICE may be converted into, for example, a filing network or a geographical coordinate point using a GIS associated with the system.

In step 418, the responding terminals are located. In a practical example, a security company may have a positioning order, i.e., for example, the youngest in office will be located first. Alternatively, all responding terminals could be located, or, for example, a certain number of first responding terminals. The positioning is implemented in practice by transmitting a positioning request or positioning requests containing at least one subscriber identity of the mobile network to the location system center of the mobile communication system. The positioning system returns the location of the terminals 20 as, for example, a reference to a mobile network or as a geographical coordinate point.

The system may also include an object selection function (step 420), whereby the called subscriber is selected such that the distance from the destination terminal (OFFICE) to the called subscriber is shortest to the responding subscribers from the calculated distances to the destination. At this point in the system, it is possible to incorporate an intelligent GIS system such that the distance is calculated, for example, by road, so that the water barrier in our example is taken into account. Correspondingly, it is sufficient for the distance calculation standard to be: ··! data on suitable metrics. For example, the distance can be calculated as an average. ** ·. 30 during that time, taking into account the instantaneous average speed distribution of the road segments.

»· • · *” · Finally, the requester of the Feasibility Study can be offered the opportunity to contact the responding terminals (422). This can be accomplished in the example SMS interface case quite simply by sending the identifiers of the responding terminals to the caller terminal device. In this case, depending on the type of terminal being used, the caller can manually contact 9 113136 by dialing the function "pick up number", after which the caller dials the correct number and dials the number of his choice. For example, reaching the security guard closest to the office, as indicated by the system caller, can be accomplished this way.

5 Due to practical needs and the former police radio phenomenon, accessibility requests usually have to be encrypted. For this purpose, in conjunction with group definition (Fig. 5, step 500), keys are generated or selected for the group to be used in step 502. This can also be accomplished by defining multiple groups. For example, the groups could be '' authorities' ',' 'fire and rescue services'', '' police ',' 'police narcotics'' and '' criminal police ''. This would associate the key created for the "" authorities "group with all the subscriber identifiers in the group. Similarly, the subscriber identifiers belonging to the "police" group but not to the "police drug department" group would not be assigned the key of the "police department" group. In addition to larger groups, one person groups as well as blank test groups can be defined.

The generated keys are stored within the reach of the SIM application arranged in connection with the mobile stations (step 504). This can be done in a number of ways. The simplest, if not cumbersome, way is to store the keys at the customer's or service provider's office. The application attached to the SIM card reader then stores the file generated by the key generator application in the specified location on the SIM card. Once the first keys are created, a key transfer mechanism that utilizes the air interface can also be defined. II. ·. non-coding methods are slightly more reliable for eavesdropping.

• · · • * · '*. The generated keys are also stored in the paging system (step 506), *. / In practice, in the target database 272 accessible by the paging system 271.

The concept of key is presented above as a fairly general concept. There are numerous cryptographic and encryption methods. It should be noted that recently, 30 public key encryption methods have become much more common. Out-.·! : the key needed to decrypt its key is located on the terminal. Also, as the terminals evolve, it is not considered impossible to have the decryption key included in the user's electronic identification card also available to the terminal. However, in the prior art resolution 35, the encryption key is stored on the subscriber identity module.

10 113136

When the terminal receives a request received as a Cell Broadcast message, the SIM application tool detects this (Figure 6, step 602). If the system is encrypted, then the SIM application drives at least a portion of the received message through the decryption filter, whereby a key stored in the s-5 is made available to the terminal for decryption. If the decryption was unsuccessful, which is detected in step 606, the message apparently was not intended for the subscriber in question and the execution ends (step 614). If the decryption was successful, or if the message was not encrypted, the query can be analyzed (step 608).

10 If the query contains an identifier which in the example case was a VARIANT corresponding to the identifier stored in the reach of the SIM application, it can be concluded in step 610 that the subscriber is the correct recipient. The message can then be answered in a predetermined manner in step 612.

One way to respond is to send an automatic reply message in the form of a ly-15 message or USSD message to a number stored in the SIM application, for example, to the emergency number. Alternatively, the terminal may send a call request to a service number reserved for access status finding, which locates the terminal attempting the call request and forwards the location result to the entity requesting the availability status request 20.

The query may also include an identifier that identifies the entity that submitted the age clearance request. In this case, the SIM application that has received the availability status request can be directed to respond, for example, to the employee who has requested the availability status for assistance '; 25 clearing requests to nearby colleagues. For this specific purpose, it is not necessary for the actual clearing request to have a definition of the mobile network area to be defined, such as a map box, as this can also be obtained if the paging system sends a locator request from the mobile system. '* 30. and then determine the area associated with the mobile network, ·! : for the query message using a possible GIS system.

The service of the invention may also be provided to consumer customers of the mobile communication network. In this case, the inquiry message may simply be of the form '' FRIENDS ', which is sent, for example, as an SMS message to the network service center via SMSC. When sending, the user sends a short message of this format to, for example, 17700, which corresponds to the value-added services identifier via text message 11113136. The system is still able to route messages to the accessibility system.

In the former case, the consumer device terminal is located and the area is selected from the mobile network based on the location result.

5 The system then generates a query message to be sent to the selected area. The message may include, for example, a consumer-customer status ID, which may also be provided in a secure message, or a nickname chosen by the consumer-customer and arranged for the consumer-customer acquaintance.

10 It is possible to store subscriber IDs and / or pseudonyms of consumer customers in the application. The users themselves can perform the recording on their terminal device, or this can be done, for example, by group messaging of SMS messages, whereby the user defines his friend (possibly in the form name + phone number) by web connection to the information system. He then activates the reachability service by, for example, sending a list of friends he has defined to the invitation system, possibly via the Internet. The paging system can handle the distribution of the user identifier to subscriber identity numbers on a predefined list, whereupon the information is stored on the SIM card of subscribers on the predefined list. When using pseudonyms, it is possible to arrange the anti-duplicate function to prevent users from being able to · ·. select existing aliases as your own aliases.

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When the application receives the query message and the one in the call

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. the identifier is found on the terminal, the terminal responds as in the previous cases ·· *. After this, it is sufficient for the calling user to be informed of the 4 · »'· * | For example, the name and / or telephone number of the first five friends who responded. As a non-exclusive alternative, these friends can also be »b · informed about the interviewer's presence in the defined area.

In the pricing of the above service, the availability of the: · · ·: is usually paid for by the sender of the first inquiry message. In this case, it is possible to implement different service response messages, *. Fees for services.

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In the case of consumer customers, flexible disconnection of the service is also very important. This can be done so that, even if ···· friends' identities are stored on the subscriber's own SIM card, the stored * 35 identities can be prioritized. In this case, for example, inquiries from entry to the VIP category will always be answered except when 12,113,136 phones are silent. In other words, different categories may depend on the mode of the phone, and answering can be turned off or on by category as needed. Useful categories may include, for example, "" Dating Club, "" "drinking Buddies," and "official bunch," which illustrate well why it may be desirable to avoid disclosing your reach to a particular group.

The query may also include an identifier that identifies the encryption key used. In particular, when receiving longer public key encryption messages, such as 256 and 512 bits, the limited las-10 field capacity of the terminal may prove to be a limiting factor. The query can then describe the key used so that the SIM application tool can begin decrypting the message with the correct key immediately.

The query can also include an identifier that describes the location area or cell identifier. The application may then be asked to compare the information stored in the subscriber identity module or the telephone memory location with the identifier in the query and to act upon the identifiers matching each other. In this case, the message can be sent over a wider area of the network, but only by requesting response from terminals within a particular domain, thus facilitating the definition of polling areas between the paging system, the GIS-20 system and the CBC systems.

It is also possible to include in the message information displayed on the terminal display] mm \:. Then you can tell him, for example, the goal • ·. the purpose of the inquiry, the purpose of the inquiry, or other similar information, such as the identity or contact details of the inquirer.

*> # '· 25 In connection with the presentation of Fig. 7, the operation of the SIM-:: application when the message arrives at the terminal will be examined in detail. When the message arrives at: the terminal, the terminal copies its funds to the subscriber identity module for messages in that block. When the message arrives in this block (step 702), the SIM application ha - *: ··: retrieves the message. If the Cell Broadcast Data Download · ": 30 feature is not supported by the terminal and the SIM, the terminal operates in accordance with the ETSI TS 23.041 specification.

The above definition states that if an incoming Cell Broadcast message I · ·

•; message identifier not found, the terminal must deduce the TS of the specifications

23.041 and TS 11.11, whether the message is displayed or not. In other words, the main: ··: The machine will check if the message is on the receive list. In practice, displaying an incoming inquiry message is not a problem if any subscriber wants to receive an incoming inquiry 1313316 standard that may be encrypted on the screen of his mobile station. This is especially true for older terminals located in the mobile network area. From the point of view of the invention, this would correspond to the situation that the subscriber time identity module of the subscriber connected to the system according to the invention has for some reason been exposed to an old terminal.

5 With terminal and subscriber identity module supported by Cell Broadcast

The Data Download property is downloaded to the application in step 706. When the complete query message is fully loaded into the application, it is launched (step 708). The application decrypts any data as described above, analyzes the contents of the query and generates, for example, a short message (step 710) and sends it (step 712). Thereafter, execution of the application stops (step 730). The application would also be able to generate and send a USSD message, respectively, or to force the terminal to establish a call and then disconnect it.

Although the invention has been described above by means of simple application examples using the GSM network as an embodiment of the invention, this is not intended to be construed as limiting the invention. The invention is to be understood in the spirit of the appended independent claims. It is trivial for a person skilled in the art to modify the implementation of the invention presented in the GSM system to correspond, for example, to a packet switched GPRS network, whereby location-area areas may also correspond to routing areas. Equally simple is implement-v. the invention in another cellular radio network, such as W-CDMA or UMTS. The idea of the invention can also be achieved by using IP-based networks, such as a WLAN, whereby the defined network areas for sending paging messages must of course be understood from the point of application.

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Claims (20)

1. A method for examining the proximity of a terminal group in a mobile communication system, characterized in that - for said group a query message is created in which there is an identifier common to the group to be called, - a notification area is defined in the mobile communication system, - the request message is sent to the determined messaging area so that it can be received with several of the mobile communication system terminals located within the said messaging area. said identifier is used in the determination, and the proximity of the terminal is examined on the basis of the response messages sent by the terminals. Method according to claim 1, characterized in that said interrogation message is transmitted as a Cell Broadcast message. Method according to claim 1, characterized in that the said reply message is a short message. Method according to claim 1, characterized in that the said reply message is a call request. Method according to claim 1, characterized in that it mentions; since the response message is a USSD message. • · * ·; Method according to claim 1, characterized in that the said interrogation message is encrypted by means of a key, which is known only to a part of the terminals of the mobile communication network, and: - the encryption of the received message is decrypted by means of:: an encryption key stored available to the terminal. ,; 30 Method according to Claim 1, characterized in that the mentioned da identifier refers to the party whose proximity is being investigated. Method according to claim 1, characterized in that said identifier refers to the party which examines the proximity. Method according to claim 6, characterized in that said identifier refers to the encryption key used. Method according to claim 1, characterized in that the proximity of the terminal is defined by positioning the mobiles that have sent a response message using the positioning method of the mobile communication system. 11. A system for examining the proximity of a terminal group in a mobile communication system, characterized in that the system contains - means for creating such a question message for the said group, which contains an identifier common to the group to be called, - means for determining a message area in the mobile communication system, - means for transmitting the request message to the determined message area, so that it can be received with several of the mobile communication system terminals, - means for receiving a reply message from mobiles arriving on the base of the message request transmission, - means for examining the proximity of the terminal on the base of the received response messages. 12. A system according to claim 11, characterized in that said transmitting means are adapted to transmit the demand message as a 20 Cell Broadcast Message. System according to claim 11, characterized in that the receiving means are adapted to receive the response message as a short message. • I 14. System according to claim 11, characterized in that the receiving means are adapted to receive the response message as a call request. System according to claim 11, characterized in that they are against -: the receiving device is adapted to receive the response message as a USSD message. '. 30 16. A system according to claim 11, characterized in that the system further comprises means for encrypting the request message by means of a key known only to a part of the mobile communication network terminals. System according to claim 11, characterized in that said identifier refers to the party whose proximity is examined. 19 113136 18. System according to claim 11, characterized in that said identifier refers to the party examining the proximity. 19. System according to claim 16, characterized in that said identifier refers to the encryption key used. 20. A system according to claim 11, characterized in that the means for examining the proximity of the terminal further contain means which are dependent on the means which receive the response messages and which are adapted to send a position determination request for the position determination of the terminal which has sent a response message to the mobile communication system. 10-meter position determination system.