KR102092561B1 - Method for Providing Contents using Visible Light Communication and Apparatus for the same - Google Patents

Abstract

Disclosed is a content providing method and apparatus using visible light communication.
According to an aspect of the present embodiment, in a mobile device that receives a visible light signal distributed to an unspecified number by visible light communication, a visible light signal including data not related to a service subscribed to by a user or a visible light installed by a malicious third party To filter the visible light signal received from the communication device, techniques for processing the visible light signal are provided.

Description

Method and Providing Contents Using Visible Light Communication and Apparatus for the same}

The present invention relates to Visible Light Communication (VLC), and more particularly, to processing of a visible light signal distributed unidirectionally to an unspecified number.

2. Description of the Related Art With the spread of portable wireless devices, communication devices using radio waves including infrared rays have been widely used. However, these communication devices have limitations due to the depletion of radio wave resources and the effects on the human body and medical devices such as the eyes.

Visible light communication is a communication method that transmits data as light using indoor / outdoor lighting, billboards, traffic lights, and street lights made of LED.It can be used even in hospitals and airplanes where use of radio waves is limited. It is receiving attention in short-range wireless communication, especially a one-way information providing system.

Korean Patent Publication No. 10-2013-0058571 Korean Registered Patent Publication No. 10-1466134

The present invention, in this one-way information providing system, the main object to provide a technique for filtering a VLC signal received from a visible light communication device installed by a malicious third party or a VLC signal not related to the service to which the user subscribes There is this.

According to another aspect of the present invention, it is intended to provide techniques for strengthening security of information distributed to an unspecified number of people in a unidirectional information providing system and supporting a paid service.

According to an aspect of the present invention, there is provided a method performed by a mobile device supporting visible light communication. The method includes: receiving a service identifier identifying a service subscribed to by a user from a service server, and storing the received service identifier; Receiving a VLC signal from the lighting device and extracting header information from the received VLC signal; Determining whether a service identifier included in the header information matches the stored service identifier; And if the service identifier included in the header information does not match the stored service identifier, discarding the received VLC signal.

The method includes: if the service identifier included in the header information matches the stored service identifier, requesting an authentication for the lighting identifier included in the header information from the management server; And discarding the received VLC signal when receiving a response that authentication of the lighting identifier has failed from the management server.

The method includes: upon receiving a response from the management server that the authentication for the lighting identifier is successful, requesting a decryption key corresponding to a sequence number included in the header information to the service server; And decrypting data included in the payload of the received VLC signal using a decryption key received from the service server.

According to another aspect of the present invention, a mobile device supporting visible light communication is provided. The mobile device includes: at least one processor; And a memory coupled to the at least one processor, the processor receiving a service identifier identifying a service subscribed to by a user from a service server, and storing the received service identifier; Receiving a VLC signal from the lighting device and extracting header information from the received VLC signal; Determining whether a service identifier included in the header information matches the stored service identifier; And if the service identifier included in the header information does not match the stored service identifier, discarding the received VLC signal.

According to another aspect of the present invention, a mobile device supporting visible light communication, comprising: means for receiving a service identifier identifying a service subscribed to by a user from a service server; Means for receiving a VLC signal from a lighting device; Means for extracting header information from the received VLC signal and determining whether a service identifier included in the header information matches the stored service identifier; And if the service identifier included in the header information does not match the stored service identifier, means for discarding the received VLC signal.

According to another aspect of the present invention, a method performed by a mobile device supporting visible light communication, comprising: receiving a VLC signal including advertisement data in a default physical layer operation mode; Providing the advertisement data to a user; In response to a user command instructing to receive paid data related to the advertisement data, requesting paid data related to advertisement data from a service server; Receiving information on a physical layer operation mode for receiving paid data from the service server; A physical layer operation mode for receiving the paid data, receiving a VLC signal including the paid data; And providing the paid data to a user.

1 is a view showing a visible light communication system according to an embodiment of the present invention.
2 is a diagram illustrating the format of a VLC data packet according to an embodiment of the present invention.
3 is a flow chart showing the operation of the visible light communication system according to an embodiment of the present invention.
4 is a flow chart showing the operation of the visible light communication system according to another embodiment of the present invention.
5 is a diagram showing an exemplary configuration of a mobile device according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. It should be noted that in adding reference numerals to the components of each drawing, the same components have the same reference numerals as possible even though they are displayed on different drawings. In addition, in describing the present invention, when it is determined that detailed descriptions of related well-known configurations or functions may obscure the subject matter of the present invention, detailed descriptions thereof will be omitted.

In addition, in describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only for distinguishing the component from other components, and the nature, order, or order of the component is not limited by the term. Throughout the specification, when a part is 'included' or 'equipped' a component, this means that other components may be further included rather than excluded, unless specifically stated to the contrary. . In addition, '… The terms "unit" and "unit" mean a unit that processes at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software.

1 is a view showing a visible light communication system according to an embodiment of the present invention.

As shown in Figure 1, the visible light communication system is composed of a visible light communication device 10, a user terminal 20, a service server 30, and a management server 50. The visible light communication device 10 is composed of an illumination device or a digital signage, and transmits a VLC signal including a VLC data packet by modulating visible light (illumination light) emitted from a light source (eg, a light emitting diode). In addition, although only one visible light communication device 10 is shown in FIG. 1, in practice, a number of visible light communication devices 10 are installed along a walkway, a road, a passage, or the like.

The user terminal 20 is composed of a mobile wireless communication device having a visible light communication function and a radio communication function using radio waves as a medium. The user terminal 2 may be implemented as a smart device such as a smart phone or a tablet PC, a laptop, a PDA, or the like.

The service server 30 is composed of a general-purpose computer system, a server operating system (server OS), and server software. Further, the service server 30 includes unique terminal identification information (terminal identifier) assigned to the user terminal 20 and a unique identifier (lighting identifier) of the visible light communication device 10 managed by the management server 50 and Addresses are stored and managed in a database. In addition, the service server 30 is equipped with a function capable of data communication between the user terminal 20 and the management server 50. The management server 50, like the service server 30, is composed of a general-purpose computer system, a server operating system, and server software. In addition, the management server 50 manages the unique identifier (lighting identifier) of the visible light communication devices 10 managed by itself and the address on the network. In addition, the management server 50 has a function capable of data communication between the user terminal 20 and the service server 30. It is also possible to divide one computer system into a plurality of virtual computer systems by a conventionally known server virtualization technology, and implement the service server 30 and the management server 50 as respective virtual computer systems.

The service server 30 acquires an identifier and an address for identifying the visible light communication device 10 managed by the management server 50 by subscribing / registering the management server 30 in advance. The service server 30 delivers the encrypted data (contents) and the distribution schedule of each content to the visible light communication device 10 via the network. The service provided by the service server 30 to the terminal may be to provide a plurality of contents that are distinguished from each other. The service server 30 may provide different contents according to time.

The visible light communication device 10 acquires the encrypted data (contents) and distribution schedule from the service server 30 via the network and stores it in memory. The visible light communication device 10 converts each content into a format suitable for the visible light communication protocol according to the distribution schedule of the content. The visible light communication device 10 transmits, for example, a VLC signal including the VLC data packet illustrated in FIG. 2. Data included in the payload of each data packet may be encrypted with different encryption keys.

The user terminal 20 needs to first subscribe to a service provided by the service server 30 via a network in order to receive content distributed as visible light from the visible light communication device 10. A unique terminal identifier (eg, mobile phone number or MAC address) of the user terminal 20 may be used when subscribing to the service. When the service subscription is successful, the user terminal 20 receives a service identifier identifying the subscribed service from the service server 30 and stores the received service identifier in memory.

When the VLC signal is received from the visible light communication device 10, the user terminal 20 uses the techniques described below, and the VLC signal not related to the service to which the user has subscribed or a visible light communication device installed by a malicious third party The VLC signal received from can be filtered. The user terminal 20 decrypts the encrypted data (or encrypted content) included in the payload of the VLC data packet illustrated in FIG. 2 using the decryption key obtained from the service server 30 via the network. can do. The user terminal 20 stores the decrypted data in the memory, and the user of the user terminal 20 selects and displays content-related information stored in the memory.

2 is a diagram illustrating the format of a VLC data packet according to an embodiment of the present invention. The packet format illustrated in FIG. 2 may be used when a visible light communication device (lighting device) transmits data to the user terminal 20 using visible light communication.

As illustrated in FIG. 2, the header includes a data type (Data Type, 211), a flag (Flag, 212), a lighting device identifier (Lighting ID, 213), a terminal identifier (Device ID, 214), and a service identifier (Service ID). , 215) and a sequence number (216) field.

The data type field 211 is a field indicating the type of data to be transmitted. Using the data type field 211, it is determined whether the type of data to be transmitted is control data for controlling the user terminal 20 or content data for transferring information to the user terminal 20. For example, if the data type field 211 has a value of 0, it indicates that the data type is content data, and if it has a value of 1, it can indicate that the data type is control data.

The flag field 212 is a field capable of confirming a sub-classification of (control / content) data to be transmitted. That is, the flag field 212 indicates a sub-classification of the type of data indicated by the data type field 212. In other words, when the data type field 212 indicates control data, the flag field 212 may indicate a sub-classification of control data. In addition, when the data type field 212 indicates that it is content data, the flag field 212 may indicate a sub-classification of content data. For example, if the flag field 212 has a value of 0, it may be control data to change the setting of the user terminal 20. If the flag field 212 has a value of 1, the control may cause the user terminal 20 to perform a specific operation. It can be data. In addition, if the flag field 212 has a value of 0, the content data may be advertisement data distributed to an unspecified terminal, and if the flag field 212 has a value of 1, the content data may indicate specific terminals that have previously subscribed to the service. It may be paid data that is distributed in order.

The lighting device identifier field 213 is a field that can identify the lighting device transmitting the corresponding data. The lighting device identifier field 213 includes the lighting device identifier for transmitting the corresponding data to the user terminal 20.

The terminal identifier field 214 is a field that can identify a terminal to receive the corresponding data. The terminal identifier field 520 includes an identifier of a terminal to receive the corresponding data. When the corresponding data is data distributed to a plurality of unspecified terminals, the terminal identifier field 520 may have a predetermined value (eg, “111 ... 11”).

The service identifier field 215 is a field that identifies a service related to the corresponding data. The service identifier field 215 includes a service identifier of a service related to the corresponding data.

The sequence number field 216 is a field for identifying data (or content) transmitted through the data packet among a series of data (or contents) transmitted by the service server 30. As described above, the service provided by the service server 30 to the user terminal 20 may be to provide a plurality of contents that are distinguished from each other. The sequence number field 216 may include a sequence number (or content identifier) for identifying corresponding data.

Also, data included in the payload may or may not be encrypted depending on the sub-type of the content data. For example, when the content data is advertisement data distributed to an unspecified terminal, the unloaded content data may be included in the payload. On the other hand, if the content data is paid data distributed for specific terminals subscribed to the service in advance, the payload may include encrypted content data. Data included in the payload of each data packet may be encrypted with different encryption keys.

Next, with reference to FIG. 3, the operation of the visible light communication system according to an embodiment of the present invention will be described. 3 is a flow chart showing the operation of the visible light communication system according to an embodiment of the present invention.

First, the user performs at least one service subscription among a plurality of services using the user terminal 20 (S310). The user terminal 20 receives a service identifier identifying the service to which the user has subscribed from the service server 30, and stores the received service identifier in the user terminal 20 (S311 to S312). The service server 30 stores subscription information in a database (S313). The subscription information may include a terminal identifier and / or a user identifier of the user terminal 20 used for service subscription and a service identifier subscribed to. The mobile phone number or MAC address assigned to the user terminal 20 may be used as the terminal identifier.

Subsequently, the user terminal 20 receives the VLC signal from the lighting device (S320). The user terminal 20 extracts header information from the VLC signal (S321).

The user terminal 20 checks whether the service identifier included in the header information matches the previously stored service identifier (that is, the service identifier identifying the service to which the user subscribes) (S323). If the two service identifiers do not match (No in S323), the user terminal 20 discards the received VLC signal and returns to the standby state to receive a new VLC signal. When the two service identifiers match (YES in S323), the user terminal 20 requests authentication of the lighting identifier included in the header information to the management server 50 through wireless communication (S324). .

If the lighting identifier received from the user terminal 20 matches the lighting identifier registered in the database, the management server 50 determines that authentication is successful, and if it does not match, it is determined that authentication is failed (S325). The management server 50 returns the authentication result (authentication success or authentication failure) to the user terminal 20 through wireless communication (S326).

If the received authentication result is an authentication failure (No in S327), the user terminal 20 discards the received VLC signal and returns to the standby state to receive a new VLC signal. If the received authentication result is successful (YES in S327), the user terminal 20 is a sequence included in the terminal identifier and header information used at the time of service subscription to obtain a decryption key for decrypting the encrypted data The number is transmitted to the service server 30.

The service server 30 queries the subscription information stored in the database, and checks whether the terminal identifier received from the user terminal 20 is the registered user. When judged to be a registered user, the service server 30 returns the decryption key corresponding to the sequence number received from the user terminal 20 to the user terminal 20 (S331). When it is determined that the user is not a registered user, the service server 30 returns an error message to the user terminal 20. In some embodiments, the service server 30 may update the billing record corresponding to the user terminal 20 after providing the decryption key.

The user terminal 20 uses the decryption key obtained from the service server 30 to decrypt the encrypted data included in the payload (S332).

As described above, the user terminal 20 ignores the corresponding VLC signal when a VLC signal irrelevant to a service previously subscribed to by the user is received based on the service identifier included in the header information extracted from the received VLC signal. And only provide data to the user that is related to the service (which may be of interest to the user) in advance.

In addition, since the user terminal 20 ignores the VLC signal received from the lighting device not registered by the management server 50, for example, the VLC signal received from the lighting device (VLC transmitter) installed by a malicious third party You can avoid the risk of executing malicious code that may be included in or providing malicious information to users. Note that the VLC infrastructure network may consist of numerous VLC transmitters to provide adequate coverage and capacity, and in such an environment, installation of a fake VLC transmitter by a malicious third party may not be easily detected.

In addition, by encrypting content distributed to a plurality of unspecified user terminals through unidirectional visible light communication, security of transmitted data can be secured, and further, encrypted content can be decrypted only to the user terminal 20 subscribed to the paid service. By providing a decryption key, charging of the paid information distribution service can be enabled.

4 is a flowchart illustrating the operation of a visible light communication system according to another embodiment of the present invention.

The user terminal 20 receives the VLC signal including advertisement data in the default physical layer operation mode (S410).

The user terminal 20 displays the received advertisement data on the display device in order to provide it to the user (S420).

When the user terminal 20 receives a command instructing to receive paid data related to advertisement data from the user, the user terminal requests the service server to pay data related to the advertisement data (S430).

After determining whether the user terminal is a paid user or updating the billing table, the service server transmits information regarding a physical layer operation mode to be used to receive paid data to the user terminal (S450). At least one of a physical layer modulation mode, an optical clock rate, and a visible light wavelength (ie, color) may be different from a default physical layer operation mode in a physical layer operation mode to be used for receiving paid data. The modulation method may be selected from, for example, on-off keying (OOK), pulse-position modulation (PPM), frequency shift keying (FSK), phase shift keying (PSK), and color-shift keying (CSK). The clock rate can be selected from, for example, 200 kHz, 400 kHz, 3.75 MHz, 7.5 MHz, 15 MHz, 30 MHz, 60 MHz, and 120 MHz. The visible light wavelength used may be, for example, 610 nm to 700 nm red, 590 nm to 610 nm yellow, 500 nm to 570 nm green, 450 nm to 500 nm blue, and 400 nm to 450 nm purple.

The visible light communication device 10 receives paid data and information about a physical layer operation mode from the service server 30 and transmits a VLC signal including the received paid data according to the received physical layer operation mode.

The user terminal 20 changes the physical layer operation mode in response to the information transmitted from the service server, and receives a VLC signal including paid data (S460). The user terminal 20 displays the received paid data on the display device in order to provide it to the user (S470).

5 is a diagram showing an exemplary configuration of a mobile device according to an embodiment of the present invention. The mobile device 500 can be used as the user terminal 20 shown in FIG. 1. The mobile device 500 may be implemented to realize the method according to the flowchart of FIG. 3 or 4.

The mobile device 500 includes a processor 510 and a memory 520 connected to each other through a bus 540, and may exchange data and information through the bus 540. The memory 520 stores application software and data / information. The mobile device 500 further includes a VLC receiving module 540 and at least one wireless communication module 560, 470. The VLC receiving module 540 and the wireless communication modules 560 and 470 are connected to the processor 510 through a bus 530.

The VLC receiving module 540 is configured to process the signals to receive visible light communication signals (VLC signals) and demodulate information and / or data transmitted from the received VLC signals. For example, the optical receiver module 540 receives a VLC signal including the VLC data packet illustrated in FIG. 2. The VLC receiving module 330 demodulates a visible light communication frame from a light receiving element (eg, a photo-diode or photo-tansistor) and an electrical signal output by the light receiving element and transmits it to the processor 510 And a demodulation circuit configured. In some embodiments, mobile device 500 may be a cellular phone that includes a camera 550 and no optical receiver module 606. In such an embodiment, the VLC signal may be received through the camera 550 included in the mobile device 500. The demodulated information / data is transferred to the processor 510. The processor 580 may generate a control signal and transmit the generated control signal to the optical receiver module 540 and the wireless communication modules 560 and 470 to control their operation. The first wireless communication module 560 is, for example, a wireless module configured to receive and transmit wireless signals (such as CDMA, LTE signals, etc.) through a mobile communication base station. The second wireless communication module 570 is, for example, a WiFi wireless module configured to receive and transmit WiFi signals through a wireless access point.

The mobile device 500 may further include a display module 580 composed of a driver circuit and a display device (eg, a liquid crystal display, an organic EL display, etc.). The driver circuit is configured to display characters, images, and images on the display device according to a control command given by the processor 510. The mobile device 500 may further include a user interface. The user interface may include a manipulation input device (eg, a keypad, a touch panel, etc.) and a manipulation input interface configured to convert the manipulation state of the manipulation input device into manipulation input data and transmit it to the processor 510.

In some embodiments, the processor is configured to receive a service identifier identifying the service to which the user has subscribed from the service server, and to store the received service identifier. Further, the processor is configured to receive the VLC signal from the lighting device, extract header information from the received VLC signal, and determine whether the service identifier included in the header information matches the stored service identifier. Further, the processor is configured to discard the received VLC signal if the service identifier included in the header information does not match the stored service identifier.

In some embodiments, if the service identifier included in the header information matches the stored service identifier, the processor requests authentication of the lighting identifier included in the header information from the management server, and the management server receives the lighting identifier from the management server. Upon receiving a response that authentication for the failed has been configured to discard the received VLC signal.

In some embodiments, the processor is configured to provide a payload of the received VLC signal to the user upon receiving a response from the management server that authentication for the lighting identifier was successful.

In some embodiments, when receiving a response from the management server that the authentication of the lighting identifier is successful, the processor requests a decryption key corresponding to the sequence number included in the header information to the service server, and the decryption key received from the service server It is configured to decode the data included in the payload of the received VLC signal by using.

The above description is merely illustrative of the technical spirit of the present embodiment, and those skilled in the art to which this embodiment belongs may be able to make various modifications and variations without departing from the essential characteristics of the present embodiment. Therefore, the present embodiments are not intended to limit the technical spirit of the present embodiment, but to explain, and the scope of the technical spirit of the present embodiment is not limited by these embodiments. The protection scope of the present embodiment should be interpreted by the claims below, and all technical spirits within the equivalent range should be interpreted as being included in the scope of the present embodiment.

Claims (12)

A method performed by a mobile device supporting visible light communication, the method comprising:
Receiving a service identifier identifying a service subscribed to by the user from the service server, and storing the received service identifier;
Receiving a VLC signal from the lighting device and extracting header information from the received VLC signal;
Determining whether a service identifier included in the header information matches the stored service identifier;
Discarding the received VLC signal if the service identifier included in the header information does not match the stored service identifier;
If the service identifier included in the header information matches the stored service identifier, requesting an authentication for the lighting identifier included in the header information from the management server;
When receiving a response from the management server that authentication for the lighting identifier has failed, discarding the received VLC signal;
Receiving a response from the management server that the authentication for the lighting identifier is successful, requesting a decryption key corresponding to a sequence number included in the header information to the service server;
Decrypting the encrypted content data included in the payload of the received VLC signal using a decryption key received from the service server; And
Providing decrypted content data to a user;
How to include. delete delete delete As a mobile device that supports visible light communication,
At least one processor; And
A memory coupled to the at least one processor,
The processor,
Receiving a service identifier identifying a service subscribed to by the user from the service server, and storing the received service identifier;
Receiving a VLC signal from the lighting device and extracting header information from the received VLC signal;
Determining whether a service identifier included in the header information matches the stored service identifier;
Discarding the received VLC signal if the service identifier included in the header information does not match the stored service identifier;
If the service identifier included in the header information matches the stored service identifier, requesting an authentication for the lighting identifier included in the header information from the management server;
When receiving a response from the management server that authentication for the lighting identifier has failed, discarding the received VLC signal;
Receiving a response from the management server that the authentication for the lighting identifier is successful, requesting a decryption key corresponding to a sequence number included in the header information to the service server;
Decrypting the encrypted content data included in the payload of the received VLC signal using a decryption key received from the service server; And
The process of providing the decrypted content data to the user
Mobile device, configured to perform. delete delete delete As a mobile device that supports visible light communication,
Means for receiving a service identifier identifying a service subscribed to by the user from the service server;
Means for storing the received service identifier;
Means for receiving a VLC signal from a lighting device;
Means for extracting header information from the received VLC signal and determining whether a service identifier included in the header information matches the stored service identifier;
Means for discarding the received VLC signal if the service identifier included in the header information does not match the stored service identifier;
Means for requesting, to the management server, an authentication for the lighting identifier included in the header information if the service identifier included in the header information matches the stored service identifier;
Means for discarding the received VLC signal upon receiving a response from the management server that authentication for the lighting identifier has failed;
Means for requesting, to the service server, a decryption key corresponding to a sequence number included in the header information when receiving a response from the management server that authentication for the lighting identifier is successful;
Means for decrypting the encrypted content data included in the payload of the received VLC signal using a decryption key received from the service server; And
Means for providing decrypted content data to users
Mobile device comprising a. delete delete delete

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