Location privacy protection method and device

Abstract

The invention provides a location privacy protection method and device, and relates to the technical field of privacy protection. When the method is executed, a target area is obtained firstly, then the target area is divided into a plurality of sub-areas, then a target sub-area is selected from the sub-areas according to a position privacy protection model, finally, whether the area of the target sub-area is smaller than the area of a set report area or not is judged, and if yes, the target sub-area is determined as the report position. Therefore, the plurality of divided sub-regions are selected through the position privacy protection model, and the selected target sub-region is determined as the report position, so that the protection effect of position privacy protection can be improved.

Description

Technical Field

[0001] The present application relates to the field of privacy protection technology, and in particular to a location privacy protection method and device. Background Art

[0002] With the popularity of mobile devices and the advancement of positioning technology, more and more applications and services are able to obtain and utilize users' location information. These location-based services can provide many convenient and personalized functions, such as navigation, social media, and advertising targeting. However, such convenient and personalized services often require users to share their location information, which raises the issue of location privacy, that is, users are worried that their location information may be abused or leaked, resulting in personal privacy exposure, increased security risks, or damage to personal rights.

[0003] As the number of people using mobile banking applications increases, users' demand for privacy protection becomes more urgent. How to effectively protect user location privacy and provide users with a location privacy protection solution that has both theoretical guarantees and high-quality services has become an important issue. In the prior art, when a user requests an LBS service, a location fuzzification mechanism is used to perturb the user's location and then send it to the LBS server, making it difficult for attackers to infer the user's true location and protecting the user's location privacy. However, this method cannot ensure the protection effect of location privacy protection.

[0004] In summary, how to improve the protection effect of location privacy protection is a problem that technical personnel in this field need to solve urgently. Summary of the invention

[0005] In view of this, the present application provides a location privacy protection method and device, aiming to improve the protection effect of location privacy protection.

[0006] In a first aspect, the present application provides a location privacy protection method, comprising:

[0007] Get the target area;

[0008] Dividing the target area into a plurality of sub-areas;

[0009] Selecting a target sub-region from the multiple sub-regions according to the location privacy protection model;

[0010] Determining whether the area of ​​the target sub-area is smaller than the set reporting area;

[0011] If so, the target sub-area is determined as the reporting location.

[0012] Optionally, before selecting a target sub-region from the multiple sub-regions according to the location privacy protection model, the method further includes:

[0013] A location privacy protection model is constructed, wherein the location privacy protection model includes a location privacy protection mechanism, information held by an attacker, and a definition of an optimal location privacy protection mechanism.

[0014] Optionally, selecting a target sub-area from the multiple sub-areas according to the location privacy protection model includes:

[0015] According to the location privacy protection mechanism, probability density functions are respectively given to the multiple sub-areas; the probability density functions satisfy the definition of the optimal location privacy protection mechanism;

[0016] A target sub-region is selected from the multiple sub-regions according to the probability density functions respectively corresponding to the multiple sub-regions.

[0017] Optionally, after determining whether the area of ​​the target sub-area is smaller than a set reporting area, the method further includes:

[0018] If not, the step of dividing the target area into a plurality of sub-areas is performed.

[0019] In a second aspect, the present application provides a location privacy protection device, including:

[0020] An acquisition module, used to acquire a target area;

[0021] A division module, used for dividing the target area into a plurality of sub-areas;

[0022] A selection module, configured to select a target sub-area from the multiple sub-areas according to a location privacy protection model;

[0023] A judging module, used for judging whether the area of ​​the target sub-area is smaller than the set reporting area;

[0024] A determination module is used to, if yes, determine the target sub-area as the reporting location.

[0025] Optionally, the device further comprises:

[0026] A construction module is used to construct a location privacy protection model, wherein the location privacy protection model includes a location privacy protection mechanism, information held by an attacker, and a definition of an optimal location privacy protection mechanism.

[0027] Optionally, the selection module includes:

[0028] A giving unit, configured to give probability density functions to the plurality of sub-areas respectively according to a location privacy protection mechanism; the probability density functions satisfy the definition of an optimal location privacy protection mechanism;

[0029] A selection unit is used to select a target sub-region from the multiple sub-regions according to the probability density functions respectively corresponding to the multiple sub-regions.

[0030] Optionally, the device further comprises:

[0031] An execution module is used for executing the step of dividing the target area into a plurality of sub-areas if no.

[0032] In a third aspect, an embodiment of the present application provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the location privacy protection method described in any one of the implementation methods in the first aspect of the embodiment of the present application.

[0033] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which instructions are stored. When the instructions are executed on a terminal device, the terminal device executes a location privacy protection method as described in any one of the implementation methods in the first aspect of the embodiment of the present application.

[0034] The present application provides a location privacy protection method. When executing the method, first obtain the target area, then divide the target area into multiple sub-areas, then select a target sub-area from the multiple sub-areas according to the location privacy protection model, and finally, determine whether the area of ​​the target sub-area is smaller than the set reporting area. If so, the target sub-area is determined as the reporting location. In this way, the location privacy protection model is used to select the multiple divided sub-areas, and the selected target sub-area is determined as the reporting location, which can improve the protection effect of location privacy protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in this embodiment or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 A flowchart of a location privacy protection method provided in an embodiment of the present application;

[0037] Figure 2 A schematic diagram of the structure of a location privacy protection device provided in an embodiment of the present application;

[0038] Figure 3 A schematic diagram of the structure of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. The present application provides a location privacy protection method and device for use in the field of privacy protection technology. The above is only an example and does not limit the application field of the method and device provided in the present application.

[0040] With the popularity of mobile devices and the advancement of positioning technology, more and more applications and services are able to obtain and utilize users' location information. These location-based services can provide many convenient and personalized functions, such as navigation, social media, and advertising targeting. However, such convenient and personalized services often require users to share their location information, which raises the issue of location privacy, that is, users are worried that their location information may be abused or leaked, resulting in personal privacy exposure, increased security risks, or damage to personal rights.

[0041] As the number of people using mobile banking applications increases, users' demand for privacy protection becomes more urgent. How to effectively protect user location privacy and provide users with a location privacy protection solution that has both theoretical guarantees and high-quality services has become an important issue. In the prior art, when a user requests an LBS service, a location fuzzification mechanism is used to perturb the user's location and then send it to the LBS server, making it difficult for attackers to infer the user's true location and protecting the user's location privacy. However, this method cannot ensure the protection effect of location privacy protection.

[0042] After research, the inventor proposed the technical solution of this application. First, the target area is obtained, then the target area is divided into multiple sub-areas, and then a target sub-area is selected from the multiple sub-areas according to the location privacy protection model. Finally, it is determined whether the area of ​​the target sub-area is smaller than the set reporting area. If so, the target sub-area is determined as the reporting location. In this way, the location privacy protection model is used to select the multiple divided sub-areas, and the selected target sub-area is determined as the reporting location, which can improve the protection effect of location privacy protection.

[0043] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application. It should be noted that, for ease of description, only the parts related to the relevant invention are shown in the accompanying drawings. In the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0044] See also Figure 1 , Figure 1 A flowchart of a location privacy protection method provided in an embodiment of the present application includes:

[0045] S101: Acquire a target area.

[0046] Get the user's current location as the target area.

[0047] S102: Divide the target area into multiple sub-areas.

[0048] The target area is divided to obtain multiple sub-areas of the target area.

[0049] S103: Select a target sub-region from multiple sub-regions according to the location privacy protection model.

[0050] Before executing step S103, it is necessary to construct a location privacy protection model, which is mainly divided into three parts: the definition of the location privacy protection mechanism, the information held by the attacker, and the definition of the optimal location privacy protection mechanism.

[0051] Definition of location privacy protection mechanism:

[0052] At present, there are two main ways in which user location privacy is violated. The first is that the communication channel itself is not secure, and attackers can eavesdrop on the communication between the user and the service provider to obtain the user's query location data. The second is that the service provider itself directly or indirectly exposes the user's query location data for commercial reasons. Due to the untrustworthiness of the service provider, the present invention focuses on a user-centric location privacy protection mechanism that provides protection for each mobile banking user individually. When the user provides his or her real location to the service provider to obtain services, the location privacy protection mechanism will blur the user's real location through privacy calculation and send a reported location to the server provider to replace the user's real location. The reported location can be the user's real location or a pseudo-location generated by the location privacy protection mechanism. Let R and R' represent the set of all real locations and the set of all reported locations. The location privacy protection mechanism is responsible for balancing the user's location privacy and the service utility of location-based services by calculating the appropriate reported location r'∈R' based on the user's real location r∈R. This application assumes that the real location set and the reported location set are the same, that is, R=R'. Therefore, the location privacy protection mechanism can be formalized as a specific probability density function f(r'|r) when the true location is r, the probability of reporting the location as r'. This formula satisfies the normalization and non-negativity of the probability density function, that is:

[0053]

[0054] Information the attacker has:

[0055] The attacker attempts to infer the user's real location r based on the knowledge he has. The present invention assumes that the attacker knows the user's reported location r' and the location privacy protection mechanism f(r'|r). At the same time, the attacker can also generate a user profile π(r) by statistically analyzing the user's historical records. This user profile can be regarded as the prior probability of the user being at r.

[0056] Definition of the optimal location privacy protection mechanism:

[0057] This application uses two important indicators to evaluate the optimality of the location privacy protection mechanism. loss The effect of location-based services is measured by the distance between the user's real location and the reported location. loss The larger P is, the greater the distance between the reported location and the true location, and the lower the quality of service that the user can enjoy. The present invention uses P to measure the user's location privacy level, expressed as the distance between the user's location estimated by the opponent and the user's true location (i.e., the estimated distance error). The larger P is, the greater the distance between the user's location estimated by the opponent and the user's true location, and the greater the location privacy level of the user when using the service. After determining these two indicators, we construct an optimization problem to obtain the optimal location privacy protection mechanism. Obviously, the optimal location privacy protection mechanism should maximize P as much as possible, and at the same time, Q should be guaranteed in the process. loss Within an acceptable range. Therefore, the optimization problem is expressed as:

[0058] f opt ≡argmaxP(π,f)

[0059]

[0060] The privacy definition formula defines the estimated position of the adversary Impact:

[0061]

[0062] The quality of service formula is defined as being affected by the user's reported location r':

[0063]

[0064] The specific steps of selecting a target sub-region from multiple sub-regions according to the location privacy protection model are as follows: for each given sub-region, construct and report the optimal probability density function of the corresponding sub-region. This probability density function will meet the definition of the optimal location privacy protection mechanism and achieve the best trade-off between user service quality and user location privacy. For multiple divided sub-regions, select one sub-region as the target sub-region based on the probability density function of each sub-region.

[0065] S104: Determine whether the area of ​​the target sub-region is smaller than the set reporting area.

[0066] Determine whether the area of ​​the target sub-region is smaller than the set reporting area. If so, execute step S105; if not, execute step S102.

[0067] S105: Determine the target sub-area as the reporting location.

[0068] In the embodiment provided by the present application, the target area is first obtained, then the target area is divided into multiple sub-areas, then a target sub-area is selected from the multiple sub-areas according to the location privacy protection model, and finally, it is determined whether the area of ​​the target sub-area is smaller than the set reporting area. If so, the target sub-area is determined as the reporting location. In this way, the location privacy protection model is used to select the multiple divided sub-areas, and the selected target sub-area is determined as the reporting location, which can improve the protection effect of location privacy protection.

[0069] The above are some specific implementations of the location privacy protection method provided in the embodiments of the present application. Based on this, the present application also provides a corresponding device. The device provided in the embodiments of the present application will be introduced from the perspective of functional modularization.

[0070] See also Figure 2 , Figure 2 A schematic diagram of the structure of a location privacy protection device provided in an embodiment of the present application, the location privacy protection device 200 includes:

[0071] An acquisition module 210 is used to acquire a target area;

[0072] A division module 220, configured to divide the target area into a plurality of sub-areas;

[0073] A selection module 230, configured to select a target sub-region from the multiple sub-regions according to a location privacy protection model;

[0074] A determination module 240 is used to determine whether the area of ​​the target sub-area is smaller than a set reporting area;

[0075] The determination module 250 is configured to, if yes, determine the target sub-area as the reporting location.

[0076] Optionally, the device 200 further includes:

[0077] A construction module is used to construct a location privacy protection model, wherein the location privacy protection model includes a location privacy protection mechanism, information held by an attacker, and a definition of an optimal location privacy protection mechanism.

[0078] Optionally, the selection module 230 includes:

[0079] A giving unit, configured to give probability density functions to the plurality of sub-areas respectively according to a location privacy protection mechanism; the probability density functions satisfy the definition of an optimal location privacy protection mechanism;

[0080] A selection unit is used to select a target sub-region from the multiple sub-regions according to the probability density functions respectively corresponding to the multiple sub-regions.

[0081] Optionally, the device 200 further includes:

[0082] An execution module is used for executing the step of dividing the target area into a plurality of sub-areas if no.

[0083] The embodiments of the present application also provide corresponding devices and computer storage media for implementing the solutions provided by the embodiments of the present application.

[0084] like Figure 3 As shown, the computer device 01 is in the form of a general computing device. The components of the computer device 01 may include but are not limited to: one or more processors or processing units 03, a system memory 08, and a bus 04 connecting different system components (including the system memory 08 and the processing unit 03).

[0085] Bus 04 represents one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, a graphics acceleration port, a processor or a local bus using any of a variety of bus structures. For example, these architectures include but are not limited to Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MAC) bus, Enhanced ISA bus, Video Electronics Standards Association (VESA) local bus and Peripheral Component Interconnect (PCI) bus.

[0086] The computer device 01 typically includes a variety of computer system readable media. These media can be any available media that can be accessed by the computer device 01, including volatile and non-volatile media, removable and non-removable media.

[0087] The system memory 08 may include computer system readable media in the form of volatile memory, such as random access memory (RAM) 09 and / or cache memory 10. The computer device 01 may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, the storage system 11 may be used to read and write non-removable, non-volatile magnetic media ( Figure 3 not shown, usually called a "hard drive"). Although Figure 3Not shown in the figure, a disk drive for reading and writing a removable non-volatile disk (e.g., a "floppy disk"), and an optical disk drive for reading and writing a removable non-volatile optical disk (e.g., a CD-ROM, a DVD-ROM, or other optical media) may be provided. In these cases, each drive may be connected to the bus 04 via one or more data medium interfaces. The memory 08 may include at least one program product having a set (e.g., at least one) of program modules that are configured to perform the functions of the various embodiments of the present invention.

[0088] A program / utility 12 having a set (at least one) of program modules 13 may be stored, for example, in the memory 08, such program modules 13 including but not limited to an operating system, one or more application programs, other program modules, and program data, each of which or some combination thereof may include an implementation of a network environment. The program modules 13 generally perform the functions and / or methods of the embodiments described herein.

[0089] The computer device 01 may also communicate with one or more external devices 02 (e.g., keyboard, pointing device, display 07, etc.), one or more devices that enable a user to interact with the computer device 01, and / or any device that enables the computer device 01 to communicate with one or more other computing devices (e.g., network card, modem, etc.). Such communication may be performed via input / output (I / O) interface 06. Furthermore, the computer device 01 may also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN) and / or public network, such as the Internet) via network adapter 05. Figure 3 As shown, the network adapter 05 communicates with other modules of the computer device 01 via the bus 04. It should be understood that although Figure 3 Not shown, other hardware and / or software modules may be used in conjunction with computer device 01, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0090] The processor unit 03 executes various functional applications and data processing by running programs stored in the system memory 08, such as implementing a location privacy protection method provided in an embodiment of the present application.

[0091] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0092] Through the description of the above implementation methods, it can be known that those skilled in the art can clearly understand that all or part of the steps in the above-mentioned embodiment method can be implemented by means of software plus a general hardware platform. Based on such an understanding, the technical solution of the present application can be embodied in the form of a software product, which can be stored in a storage medium, such as a read-only memory (ROM) / RAM, a magnetic disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network communication device such as a router) to execute the methods described in each embodiment of the present application or some parts of the embodiments.

[0093] Each embodiment in this specification is described in a progressive manner, and the same and similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative work.

[0094] The above description is merely an exemplary embodiment of the present application and is not intended to limit the protection scope of the present application.

Claims

1. A location privacy protection method, characterized in that: include: Get the target area; Dividing the target area into a plurality of sub-areas; Selecting a target sub-region from the multiple sub-regions according to the location privacy protection model; Determining whether the area of ​​the target sub-area is smaller than the set reporting area; If so, the target sub-area is determined as the reporting location.

2. The method according to claim 1, characterized in that: Before selecting a target sub-region from the multiple sub-regions according to the location privacy protection model, the method further includes: A location privacy protection model is constructed, wherein the location privacy protection model includes a location privacy protection mechanism, information held by an attacker, and a definition of an optimal location privacy protection mechanism.

3. The method according to claim 2, characterized in that The selecting a target sub-area from the multiple sub-areas according to the location privacy protection model includes: According to the location privacy protection mechanism, probability density functions are respectively given to the multiple sub-areas; the probability density functions satisfy the definition of the optimal location privacy protection mechanism; A target sub-region is selected from the multiple sub-regions according to the probability density functions respectively corresponding to the multiple sub-regions.

4. The method according to claim 1, characterized in that: After determining whether the area of ​​the target sub-area is smaller than the set reporting area, the method further includes: If not, the step of dividing the target area into a plurality of sub-areas is performed.

5. A location privacy protection device, characterized in that: include: An acquisition module, used to acquire a target area; A division module, used for dividing the target area into a plurality of sub-areas; A selection module, configured to select a target sub-area from the multiple sub-areas according to a location privacy protection model; A judging module, used for judging whether the area of ​​the target sub-area is smaller than the set reporting area; A determination module is used to, if yes, determine the target sub-area as the reporting location.

6. The device according to claim 5, characterized in that The device also includes: A construction module is used to construct a location privacy protection model, wherein the location privacy protection model includes a location privacy protection mechanism, information held by an attacker, and a definition of an optimal location privacy protection mechanism.

7. The device according to claim 6, characterized in that The selection module comprises: A giving unit, configured to give probability density functions to the plurality of sub-areas respectively according to a location privacy protection mechanism; the probability density functions satisfy the definition of an optimal location privacy protection mechanism; A selection unit is used to select a target sub-region from the multiple sub-regions according to the probability density functions respectively corresponding to the multiple sub-regions.

8. The device according to claim 5, characterized in that The device also includes: An execution module is used for executing the step of dividing the target area into a plurality of sub-areas if no.

9. A computer device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the location privacy protection method as described in any one of claims 1 to 4 is implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, and when the instructions are executed on a terminal device, the terminal device executes the location privacy protection method as described in any one of claims 1 to 4.

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