Patent Publication Number: US-2023164514-A1

Title: A method for notifying a first mobile terminal of an event related to a second mobile terminal

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is filed under 35 U.S.C. § 371 as the U.S. National Phase of Application No. PCT/IB2021/000212 entitled “A METHOD FOR NOTIFYING A FIRST MOBILE TERMINAL OF AN EVENT RELATED TO A SECOND MOBILE TERMINAL” and filed Mar. 31, 2021, and which claims priority to PCT/CN2020/083254 filed Apr. 3, 2020, each of which is incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     Field 
     The present disclosure relates to a method for tracking mobile terminals in order to notify them of the occurrence of an event based on their moving about history. 
     Description of Related Technology 
     In some situations, it would be useful to be capable of contacting nonspecific individuals who may have been in nearby contact with one or more specific individuals in the recent past, in order to contact these nonspecific individuals when necessary. 
     For instance, in situation of as a pandemic, it would be useful to be capable of contacting nonspecific individuals who may have been in nearby contact in the recent past with one or more individuals infected by a contagious virus, in order to alert these nonspecific individuals that they may have been infected by this virus, and thus allow them to take the necessary measures to prevent further spreading of the disease. 
     Another example is the situation where one looks for a criminal: it would be useful to be capable of contacting nonspecific individuals who may have been in nearby contact with a criminal suspect in the recent past, in order to request these nonspecific individuals to provide any suspicious event they would have witnessed. 
     While telecom operators can provide some data making it possible to retrace the route of an individual by means of connection information from the individual&#39;s mobile terminal to the various base stations of a cellular network, such information is not always sufficient to retrace precisely an individual&#39;s route, in particular when it takes place inside buildings or in underground structures such as metro tunnels, etc. As such, these data do not allow checking whether different individuals have been at the same time in the very same place. 
     SUMMARY 
     The present development was designed with the foregoing in mind. 
     The present development concerns a method for notifying on a first mobile terminal an event related to a second mobile terminal, comprising:
         collecting first parameters associated with at least one short-range radio communication device detected by the first mobile terminal, and   playing information on the first mobile terminal about an event related to the second mobile terminal when a match is detected between at least one of said first parameters and at least one second parameters associated with at least one short-range radio communication device detected by the second mobile device, said second parameters being collected by the second mobile device.       

     The present solution relies on the use of short-range radio communication techniques such as Wi-Fi, Bluetooth, NFC (Near-Field Communication), etc. which are largely used indoor to provide a better connectivity. Due to the short-range of these communication techniques, the route of an individual can be obtained more precisely than with methods of the prior art. 
     Thus, throughout its route, a mobile terminal collects parameters associated with the various short-range radio communication devices within the range of which it finds itself. Such short-range radio communication devices may be other mobile terminals, Wi-Fi hotspots, NFC enabled terminals used to control transport tickets, etc. 
     Knowing the route of a given individual based on these collected parameters, it is possible to inform this individual that he/she encountered an infected individual. 
     A notification is played on the mobile device of the individual informing him/her of this encounter. This notification can be a message, such as a text message, displayed on a screen of the mobile device, a vocal message played by a speaker of the mobile device, or both. 
     According to an embodiment of the method for notifying an event related to another mobile terminal, said parameters associated with said at least one short-range radio communication device comprise an identifier of said at least one short-range radio communication device. 
     Sometimes, an identifier of a short-range radio communication device conveys enough information for a user of a mobile terminal to know the time and place at which he/she may have encountered an infected individual. An example of such an explicit identifier of a short-range radio communication device can be “bestcoffee-shop-toureiffel”. The user of the mobile terminal being notified the identifier of the short-range radio communication device can determine the place of the encounter and a date and time at which he/she stopped at this coffee shop. 
     According to an embodiment of the method for notifying an event related to another mobile terminal, the parameters associated with said at least one short-range radio communication device further comprise at least one of:
         a timestamp indicating a time at which said mobile terminal enters the range of said at least one short-range radio communication device, and   a timestamp indicating a time at which said mobile terminal leaves the range of said at least one short-range radio communication device.       

     It is thus possible to determine the time at which the encounter took place. This information can help the individual identify people he/she met after the encounter with an affected individual took place and inform them. It is also possible to determine an estimate of the time spent in the vicinity of an infected individual. 
     According to an embodiment of the method for notifying an event related to another mobile terminal, the collected parameters associated with said at least one short-range radio communication device further comprise a location of said at least one short-range radio communication device or the location of the second mobile terminal when the collected parameters do not comprise the location of said short-range radio communication device. 
     As a result, an accurate location of the encountered can be notified to the user of the mobile terminal. 
     According to an embodiment of the method for notifying an event related to another mobile terminal, the method further comprises storing said first parameters in a memory of said first mobile terminal. The collected parameters are then stored locally, either for being processed by the mobile device or to be transmitted later on to a remote processing device. 
     According to an embodiment of the method for notifying an event related to another mobile terminal, the first parameters are encrypted prior to their storing. The collected parameters are then protected in case the mobile terminal get hacked. 
     According to an embodiment of the method for notifying an event related to
         another mobile terminal, when the collected parameters are processed by the mobile terminal, the method further comprises:   receiving said second parameters associated with at least one short-range radio communication device detected by the second mobile device,   determining a match between at least one first parameters and at least one second parameters associated with at least one short-range radio communication device detected by the second mobile device, the determination of a match between at least one first parameter and at least one second parameter triggering the playing of information on the first mobile terminal about an event related to the second mobile terminal.       

     In this implementation, the mobile terminal receives parameters associated with at least one short-range radio communication device collected by a mobile terminal whose user is infected. The parameters associated with said short-range radio communication device may comprise the location of said short-range radio communication device, a time and a location. 
     By comparing this information of time and location, the mobile device determines if there is a match, i.e. was the mobile terminal within range of the short-range radio communication device of the infected individual. 
     If there is a match, a notification is played on the mobile device informing the user of this encounter. 
     This implementation is more protective, in terms of user&#39;s privacy: the user device history is uploaded to a remote server only when necessary, i.e. when there is a request from other users who wish to know if they were in the vicinity of the infected individual. 
     According to an embodiment of the method for notifying an event related to another mobile terminal, the method further comprises: 
     transmitting said first parameters to a remote server storing said second parameters, 
     receiving said information about an event related to the second mobile terminal when said remote server detects a match between at least one first parameters and at least one second parameters. 
     By comparing this information of time and location, the remote server determines if there is a match, i.e. was the mobile terminal within range of the short-range radio communication device of the infected individual. 
     If there is a match, a request for playing a notification on the mobile device informing the user of this encounter is sent to the mobile device. 
     This implementation requires a large data storage capacity on the remote server, but then the inquiry to find individuals in order to inform them can be made directly on the remote server, in a transparent way for the mobile terminal itself. 
     Another object of the development is a method for tracking a mobile terminal, said method being executed by a tracking device and comprising:
         receiving first parameters associated with at least one short-range radio communication device detected by a first mobile terminal and collected by said first mobile terminal,   receiving second parameters associated with at least one short-range radio communication device detected by a second mobile terminal and collected by said second mobile terminal,   determining if there is a match between at least one first parameters and at least one second parameters, and   when there is a match between said at least one first parameters and said at least one second parameters, requesting a playing of information on the first mobile terminal about an event related to the second mobile terminal.       

     The development also concerns a mobile terminal capable of notifying an event related to another mobile terminal, said mobile terminal comprising a processor configured to:
         collect first parameters associated with at least one short-range radio communication device detected by the mobile terminal, and   play information on the mobile terminal about an event related to the other mobile terminal when a match is detected between at least one first parameters and at least one second parameters associated with at least one short-range radio communication device detected by the other mobile device, said second parameters being collected by the other mobile device.       

     A fourth object of the development is a tracking device capable of tracking a mobile terminal, said a tracking device comprising a processor configured to:
         receive first parameters associated with at least one short-range radio communication device detected by a first mobile terminal and collected by said first mobile terminal,   receive second parameters associated with at least one short-range radio communication device detected by a second mobile terminal and collected by said second mobile terminal,   determine if there is a match between at least one first parameters and at least one second parameters, and   when there is a match between said at least one first parameters and said at least one second parameters, request a playing of information on the first mobile terminal about an event related to the second mobile terminal.       

     According to an embodiment of the development, said tracking device is embedded in the mobile device as previously discussed. 
     According to another embodiment of the development, said tracking device is embedded in a remote server. 
     Some processes implemented by elements of the development may be computer implemented. Accordingly, such elements may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit”, “module” or “system”. Furthermore, such elements may take the form of a computer program product embodied in any tangible medium of expression having computer usable program code embodied in the medium. 
     Since elements of the present development can be implemented in software, the present development can be embodied as computer readable code for provision to a programmable apparatus on any suitable carrier medium. A tangible carrier medium may comprise a storage medium such as a floppy disk, a CD-ROM, a hard disk drive, a magnetic tape device or a solid-state memory device and the like. A transient carrier medium may include a signal such as an electrical signal, an electronic signal, an optical signal, an acoustic signal, a magnetic signal or an electromagnetic signal, e.g. a microwave or RF signal. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure can be better understood with reference to the following description and drawings, given by way of example and not limiting the scope of protection, and in which: 
         FIG.  1    represents a system in which different embodiments of the method for notifying an event and the method for tracking a mobile terminal can be executed, 
         FIG.  2    represents a diagram of exchanges between different communication devices involved in the implementation of the method for notifying an event and the method for tracking a mobile terminal in a first embodiment of the development, 
         FIG.  3    represents a diagram of exchanges between different communication devices involved in the implementation of the method for notifying an event and the method for tracking a mobile terminal in a second embodiment of the development, 
         FIG.  4    represents a detailed view of one of the mobile terminal  10  according to the development, and 
         FIG.  5    represents a detailed view of the tracking device  15  according to the development. 
     
    
    
     The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the development. 
     DETAILED DESCRIPTION OF CERTAIN ILLUSTRATIVE EMBODIMENTS 
       FIG.  1    represents a system in which different embodiments of the method for notifying an event and the method for tracking a mobile terminal can be executed. 
     The system comprises at least a first mobile terminal  10  and a second mobile terminal  12 , a first short-range radio communication device  11  (which in this example is a Wi-Fi access node), a second short-range radio communication devices  13  (which in this example is another mobile terminal) and a remote server  14 . 
     In the following, the second mobile terminal  12  is supposed to be owned by a specific individual, such as an individual being diagnosed as infected by a contagious virus. Mobile terminals  10  and  12 , short-range radio communication device  11 ,  13  and remote server  14  may embed a tracking device  15 , as discussed thereafter. 
     The mobile terminals  10 ,  12  may each possess a respective unique identifier Id 10 , Id 12  such as a universally unique identifier (UUID) defined in the document RFC 4122 published by the IETF (Internet Engineering Task Force). A UUID is a 128-bit number used to identify information in computer systems. 
     The functions and interconnexions between those different devices will be explained in reference to  FIGS.  2 - 5   . 
       FIG.  2    represents a diagram of exchanges between different communication devices involved in the implementation of the method for notifying an event and the method for tracking a mobile terminal in a first embodiment of the development. In this first implementation, only the remote server  14  embeds a tracking device  15 . 
     In step SI, the mobile terminal  10  enters the range of the first short-range radio communication device  11 . This is typically the case when the mobile terminal  10  starts detecting a radio signal constantly or periodically emitted by device  11 . 
     In a step S 2 , the mobile terminal  10  collects parameters associated with the short-range radio communication device  11  it has detected. These parameters comprise a unique identifier Id 11  of this short-range radio communication device  11 , here the SSID of the Wi-Fi network provided by the short-range radio communication device  11  when device  11  is a Wi-Fi access node. 
     These collected parameters may optionally comprise as well a location of the short-range radio communication device  11 , if provided. In a specific embodiment where the mobile terminal  10  fails to obtain this location of the short-range radio communication device  11 , the mobile terminal  10  may instead collect its own location, obtained for instance by means of a geo-localization module (e.g. GPS) embedded in the mobile terminal  10 . 
     Once collected, those parameters are timestamped, for instance to associate a specific day and time with the identifier of the detected device  11 . In order to do so, for each detected short-range communication device  11 ,  13 , the collected parameters may comprise the identifier Id 11 , Id 13  in association with:
         a timestamp indicating a time at which mobile terminal  10  has entered the range of, or connected with, this short-range radio communication,   a timestamp indicating a time at which mobile terminal  10  has left the range of, or disconnected from, this short-range radio communication device (i.e. the time at which it does not detect it any longer), or   both these above-mentioned time stamps.       

     In a first embodiment, step S 2  is executed when the mobile terminal  10  connects to the short-range radio communication device  11 . In this embodiment where only the connection to a short-range radio communication device triggers the parameters collection, there can be holes in time, in terms of user localization, since the mobile terminal  10  does not continuously connect to a short-range radio communication device such as devices  11  or  13 . 
     In another embodiment, the mobile terminal  10  collects parameters associated with any short-range radio communication device  11 ,  13  it detects, without actually establishing a connection with these short-range radio communication device  11 , 13 . In this embodiment, the mobile terminal  10  collects parameters associated with each the short-range radio communication device  11 ,  13  it passes by, as long as the mobile terminal  10  passes within their range. 
     In this embodiment, not only the mobile terminal  10  collects parameters when connecting to short-range radio communication device  11 , but also when detecting a nearby short-range radio communication device  13 , without connecting to it. As a consequence, this embodiment gives a more precise picture of the mobile terminal  10  route. 
     From time to time, the mobile terminal  10  transmits the collected parameters of each short-range radio communication device  11 ,  13  it has encountered, for example as a list L 10 , to the remote server  14 . This transmission occurs during a step S 3 . 
     More precisely, for each short-range radio communication device  11 ,  13  encountered, the mobile terminal  10  stores in list L 10  the respective identifier Id 11 , Id 13  of the short-range radio communication devices  11 , 13  (e.g. the SSIDs of the Wi-Fi network provided by the short-range radio communication devices  11  and  13 ) or any other identifier of a short-range radio connection provided by these short-range radio communication devices  11 ,  13 , with also possibly a respective location of these short-range radio communication devices  11 , 13  and at least a timestamp indicating a time at which those parameters are collected. 
     In case a connection is established between the mobile terminal  10  and a short-range radio communication device  11  or  13 , a duration of this connection may be stored in the list L 10  as well. 
     Steps S′ 2  and S′ 3 , similar respectively to steps S 2  and S 3  as above, are also executed by mobile terminal  12 . 
     In a step S 4 , the remote server  14  receives a message about an event related to terminal mobile  12  which should be notified to other mobile terminals. Such an event may be for instance the fact that a user of mobile this mobile terminal  12  has been diagnosed as being infected by a contagious virus. A possible date of infection is also provided to the remote server  14 . The infection of the user of the mobile terminal  12  may be thus referred to as an event related to this mobile terminal  12 . The remote server  14  forwards this information to the tracking device  15 . 
     For each mobile terminal different from the mobile terminal  12  related to the event to notify (here for mobile terminal  10  in  FIG.  2   , but could be for any greater number of mobile terminals), the tracking device  15  uses the parameters collected by this mobile terminal  10  and the parameters collected by the mobile terminal  12 , in order to find individuals which have been in the vicinity of the user of the mobile terminal  12 , at a given time. Here, when also provided, the supposed date of infection may be used to determine a time window in which the server  14  will look for individuals which have been in the vicinity of the user of mobile terminal  12 . This time window can take into account the incubation period of the disease. 
     In a step S 5 , the tracking device  15  extracts from list L 10  a first set of parameters collected by mobile terminal  10  and whose timestamps are within the time window. The tracking device  15  extracts as well, from a list L 12 , a second set of parameters collected by mobile terminal  12  and whose timestamps are within the time window. 
     In a step S 6 , the tracking device  15  compares the first set of parameters collected by mobile terminal  10  with the second set of parameters collected by mobile terminal  12  in order to determine if there is at least one parameter related to the same short-range radio communication device  11  or  13  in both first and second set of parameters. 
     In that respect, when an identifier Id 11  or Id 13  of a short-range radio communication device  11 ,  13  has been collected in both the first and the second set of parameters, with the same associated timestamps or relatively close timestamps (for instance within an hour interval), then it is determined that the mobile terminal  10  was in the vicinity of the mobile terminal  12  of the infected individual substantially at the same time during the time window. 
     In a specific embodiments where the collected parameters comprise both time stamps indicating when the mobile terminal has entered into the range (resp. has connected with) and has left the range (resp. has disconnected with) of the short-range communication device, then a verification is made as to whether the same identifier Id 11  or Id 13  is collected by both terminals with overlapping time intervals (defined by the collected time stamps). When this is the case, then it is determined that the mobile terminal  10  was in the vicinity of the mobile terminal  12  of the infected individual substantially at the same time during the time window. 
     In another specific embodiment where the tracking device  15  knows about the identifier Id 12  of the mobile terminal acting as a short-range radio communication device (i.e. when it acts as a wifi access point for instance), if the tracking device  15  determines that this identifier Id 12  of the mobile terminal  12  is comprised in the first set of parameters collected by mobile terminal  10  whose timestamps are within the time window, then the tracking device  15  may determine that the mobile terminal  10  was within direct short range of the mobile terminal  12  of the infected individual at some time during the time window. 
     Once a match between the mobile terminal  10  and the mobile terminal  12  of the infected user is detected, the tracking device  15  embedded in the remote server  14  generates, m a step S 7 , one or more parameters associated with said event. These parameters comprise information that an infected individual was in the vicinity mobile terminal  10 . They may also comprise identifiers Id 11 , Id 13  of the short-range radio communication device  11 ,  13  identified by the tracking device  15 , the location of said short-range radio communication device  11 ,  13 , and an indication of a time and date at which the encounter occurred. 
     In a step S 8 , the tracking device  15  embedded in the remote server  14  sends a request RQS to the mobile terminal  10  comprising the parameters associated with the event and requesting the mobile terminal  10  to play a notification comprising information about said event, such as “you were near an infected individual”, for instance. 
     When additional information such as the location of the short-range communication device (or of the mobile terminal when it has failed to collect it) or a timestamp associated with the identifier Id 11 , Id 13  has been collected, this information can be used to enrich the notification, such as “you were near an infected individual on Month Day Year, time, at location X” for instance. 
     In a step S 9 , the mobile terminal  10  plays this notification. This notification can be a message, such as a text message, displayed on a screen of the mobile device  10 , or a vocal message played by a speaker of the mobile device  10 , or both. 
       FIG.  3    represents a diagram of exchanges between different communication devices involved in the implementation of the method for notifying an event and the method for tracking a mobile terminal in a second embodiment of the development. In this second implementation, the tracking device  15  is embedded in mobile terminal  10 , and in short-range radio communication devices  12  and  13 . 
     In a step RI, the mobile terminal  10  enters the range of the first short-range radio communication device  11 . 
     In a step R 2 , the mobile terminal  10  collects parameters associated with the short-range radio communication device  11 , including its unique identifier Id 11 , here the SSID of the Wi-Fi network provided by the short-range radio communication device  11  since device  11  is a Wi-Fi access node. The collected parameters may also possibly comprise a location of the short-range radio communication device  11  or, when the mobile terminal fails to obtain such a location, the location of the mobile terminal  10  itself, as described previously. Once collected, those parameters are timestamped as described in relation to  FIG.  2   . 
     Just as in the previous embodiment, step R 2  may be executed when the mobile terminal  10  connects to a short-range radio communication device  11 , 13  or when it detects one of them, without establishing a connection with the short-range radio communication device  11 ,  13 . 
     In a step R 3 , the mobile terminal  10  stores locally the collected parameters of each short-range radio communication device  11 ,  13 , it has encountered, for example as a list L 10 , in its memory. To increase data privacy, the list L 10  is encrypted prior to being stored. 
     For each short-range radio communication device  11 ,  13  encountered, the mobile terminal  10  stores in list L 10  the identifier Id 11 , Id 13 , of the short-range radio communication devices  11 ,  13  (e.g. the SSID of the Wi-Fi connection provided by the short-range radio communication devices  11 ) or any other identifier of a short-range radio connection provided by the short-range radio communication device  13 , with possibly a location of the short-range radio communication devices  11 ,  13  (or alternatively of the mobile terminal  10  itself when it fails to obtain it), and at least a timestamp indicating a time at which those parameters are collected. In case a connection is established between the mobile terminal  10  and one of short-range radio communication devices  11 ,  13 , a duration of this connection may also be stored in the list L 10  as well. 
     Steps R 2 ′ and R 3 ′, which are similar respectively to steps R 2  and R 3  as above, are also executed by mobile terminal  12 . 
     At this stage, each one of mobile terminals  10  and  12  stores a list comprising information about its whereabouts. 
     In this second implementation, there is no automatic upload of all the collected parameters to the remote server  14 , but rather an upload of parameters collected by a specific mobile terminal  10  or  12 , when necessary. 
     In a step R 4 , the remote server  14  receives a message informing it that a user of mobile terminal  12  is, for example, infected by a contagious disease. A possible date of infection may also be provided to the remote server  14  at this stage, this date of infection being useable to determine a time window in which individuals who have been in the vicinity of the user of mobile terminal  12  will be looked for. This time window can take into account the incubation period of the disease. The infection of the user of mobile terminal  12  is referred to as an event related to this mobile terminal  12 . 
     In a step R 5 , the remote server  14  sends a request RQS 1  to the mobile terminal  12 , the user of which is infected, asking it to transmit its list L 12  of collected parameters to the remote server  14  where it is stored together with the identifier Id 12  of the mobile terminal  12 , for later use. 
     In a step R 6 , the mobile terminal  12  transmits its list L 12  of collected parameters to the remote server  14  together with its identifier Id 12  in a message MSG 1 . 
     At some point, a user of the mobile terminal  10  wants to know if he/she was in contact with an infected individual. The user of the mobile terminal  10 , by means of a user interface of the mobile terminal  10 , triggers the sending of a request RQS 2  to the remote server  14 , in a step R 7 , asking for the lists of collected parameters of mobile terminals whose user declared themselves as infected. 
     In a step R 8 , in response to request RQS 2 , the remote server  14  transmits the list L 12  of parameters collected by the mobile terminal  12 , together with the supposed date of infection of the user of mobile terminal  12  and/or the time window, to the mobile terminal  10  in a message MSG 2 . Here, the list L 12  collected by only one mobile terminal  12  is transmitted for illustration, but several lists, respectively collected by different mobile terminals belonging to infected users, could be transmitted to mobile terminal  10 , naturally. 
     In a step R 9 , the tracking device  15  embedded in mobile terminal  10  uses the parameters collected by mobile terminal  10  and the parameters collected by mobile terminal  12 , together with the time window, in order to determine if the mobile device  10  and the mobile terminal  12  have been in the vicinity of the same short-range radio communication device  11 ,  13  around the same given time. 
     In a step R 10 , the tracking device  15  extracts from list L 10  a first set of parameters collected by mobile terminal  10  and whose timestamps are within the time window. The tracking device  15  extracts as well, from a list L 12  a second set of parameters collected by mobile terminal device  12  and whose timestamps are within the time window. 
     In a step R 11 , the tracking device  15  compares the first set of parameters collected by mobile terminal  10  with the second set of parameters collected by mobile terminal  12  in order to determine if there is at least one parameter related to a short-range radio communication device  11 ,  13  which is common to the first and the second set of parameters. 
     For instance, when an identifier Id 11  or Id 13  of a short-range radio communication device  11 ,  13  is common to the first and the second set of parameters, then it is determined that the mobile terminal  10  was in the vicinity of the mobile terminal  12  of the infected individual at some time during the time window. 
     Once a match between the mobile terminal  10  and mobile terminal  12  of the infected user is detected, the tracking device  15  embedded in the mobile terminal  4  generates, in a step R 12 , one or more parameters associated with said event. These parameters comprise an information that an infected individual was in the vicinity mobile terminal  10 . They may also comprise an identifier Id 11 , Id 13  of the short-range radio communication device  11 ,  13  identified by the tracking device  15 , the location of said short-range radio communication device  11 ,  13 , and an indication of a time and date at which the encounter occurred. 
     In a step R 13 , the tracking device  15  triggers the playing a notification comprising information about said event such as “you were near an infected individual on Month Day Year, time, at location X”. This notification can be a message, such as a text message, displayed on a screen of the mobile device  10 , or a vocal message played by a speaker of the mobile device  10 , or both. 
     In another embodiment of the second implementation of the method for notifying an event and the method for tracking a mobile terminal, the tracking device  15  is embedded in the remote server  14 , not in the mobile terminal  10 , and steps R 8  to R 13  are not executed. Instead, in this embodiment, a user of the mobile terminal  10  who wants to know if he/she was in contact with an infected individual, triggers, by means of the user interface of the mobile terminal  10 , the transmission of its own list L 10  of collected parameters to the remote server  14  together with a request for determining whether the mobile terminal  10  was within range of a short-range radio communication device  12  belonging to an infected individual or not. 
     Upon reception of this request by the remote server  14 , steps S 5  to S 9  are executed as explained in reference to  FIG.  2   . 
       FIG.  4    represents a detailed view of one of the mobile terminal  10  according to the development. 
     A mobile terminal  10  may comprise at least one hardware processor  41 , a storage unit  42 , an input device  43 , a display device  44 , and a network interface  45 , which are typically connected by a data bus  46 . Of course, constituent elements of the mobile terminal  10  may be connected by a connection other than a data bus connection. 
     The hardware processor(s)  41  controls operations of the mobile terminal  10 . The storage unit  42  stores at least one program capable of notifying a mobile terminal of an event linked to another mobile terminal to be executed by the processor  41 , and various data, such as parameters used by computations performed by the processor  41 , intermediate data of computations performed by the processor  41 , and so on. The processor  41  may be formed by any known and suitable hardware, or software, or a combination of hardware and software. For example, the processor  41  may be formed by dedicated hardware such as a processing circuit, or by a programmable processing unit such as a CPU (Central Processing Unit) that executes a program stored in a memory thereof 
     The storage unit  42  may be formed by any suitable storage or means capable of storing the program, data, or the like in a computer-readable manner. Examples of the storage unit  42  include non-transitory computer-readable storage media such as semiconductor memory devices, and magnetic, optical, or magneto-optical recording media loaded into a read and write unit. The program causes the processor  41  to perform a process according to an embodiment of the present development as described with reference to  FIGS.  2  and  3   . 
     The input device  43  may be formed by a keyboard, a pointing device such as a mouse, or the like for use by the user to input commands, for example to make user&#39;s selections of parameters used for selecting the level of proficiency of the reader in reading logograms. 
     The display device  44  and the input device  43  may be formed integrally by a touchscreen panel. 
     A network interface  45  provides a connection between the mobile terminal  10  and short-range radio communication devices  11 ,  12 ,  13  and a remote server  14 . 
       FIG.  5    represents a detailed view of the tracking device  15  according to the development. 
     A tracking device  15  may comprise at least one hardware processor  51 , a storage unit  52 , and an interface  53 , which are typically connected by a data bus  54 . Of course, constituent elements of the tracking device  15  may be connected by a connection other than a data bus connection. 
     The hardware processor(s)  51  controls operations of the tracking device  15 . The storage unit  52  stores at least one program capable of tracking a mobile terminal to be executed by the processor  51 , and various data, such as parameters used by computations performed by the processor  51 , intermediate data of computations performed by the processor  51 , and so on. The processor  51  may be formed by any known and suitable hardware, or software, or a combination of hardware and software. For example, the processor  51  may be formed by dedicated hardware such as a processing circuit, or by a programmable processing unit such as a CPU (Central Processing Unit) that executes a program stored in a memory thereof 
     The storage unit  52  may be formed by any suitable storage or means capable of storing the program, data, or the like in a computer-readable manner. Examples of the storage unit  52  include non-transitory computer-readable storage media such as semiconductor memory devices, and magnetic, optical, or magneto-optical recording media loaded into a read and write unit. The program causes the processor  51  to perform a process according to an embodiment of the present development as described with reference to  FIGS.  2  and  3   . 
     The interface  53  provides a connection between the tracking device  15  and the mobile terminal  10  or the remote server  14 . 
     Although the present development has been described hereinabove with reference to specific embodiments, the present development is not limited to the specific embodiments, and modifications will be apparent to a skilled person in the art which lie within the scope of the present development. 
     In particular, the present development has been described in details in the specific context of the notification, on a mobile terminal, that the user of another terminal has been diagnosed as infected by a contagious virus. However, the present development can apply to any other type of event worthy to be notified on a mobile terminal, when this event is related to another mobile terminal that has been in short proximity of this terminal in a recent past. 
     In addition, the case of a single mobile terminal  10  being notified has been illustrated in  FIGS.  2  and  3   , for the sake of explaining the development. However, any number of mobile terminals  10  can be notified of an event related to a mobile terminal  12 , using the same embodiments as discussed previously. Similarly, the case of a single mobile terminal  12  triggering the notification on mobile terminal  10  has been illustrated in  FIGS.  2  and  3   , for the sake of explaining the development. However, events related to any number of mobile terminals  12  can be notified on one (or more) mobile terminal  10 , using the same embodiments as discussed previously. 
     Many further modifications and variations will suggest themselves to those versed in the art upon making reference to the foregoing illustrative embodiments, which are given by way of example only and which are not intended to limit the scope of the development, that being determined solely by the appended claims. In particular the different features from different embodiments may be interchanged, where appropriate.