KR20090055136A - Content delivery method and system using location information - Google Patents

Abstract

The present invention relates to a content transmission technology, and more particularly, to a content transmission method and system using location information for encoding and decoding content using location information of a receiving terminal in transmitting content.

To this end, a location information acquisition process of acquiring location information of a second terminal from a first terminal according to a content transmission request, and encoding encoding content to be transmitted using the location information of the second terminal acquired by the first terminal. Content, the location information including a transmission process of transmitting, by the first terminal, the encoded content to the second terminal, and a decoding process of decoding the content transmitted from the second terminal using location information. Provides a transmission method and system.

According to the present invention, since the use of the content is restricted by using the location information of the second terminal as the authentication key, the authentication key can be easily obtained and used. In addition, we propose a new copyright management method for acquiring the right to use content according to the user's location.

Description

Method and system for transmitting content using position information {Method and systems for transmitting content using position information}

The present invention relates to a content transmission technology using location information, and more particularly, to a content transmission method and system using location information for encoding and decoding content using location information of a receiving terminal in transmitting content.

In general, a mobile communication terminal is a personal mobile communication service terminal (Personal Mobile Communication Services Terminal), a personal digital assistant (PDA), a smart phone (Smart Phone), the next generation mobile communication terminal (International Mobile Telecommunication 2000: IMT-2000) And a terminal capable of implementing various functions using an application program including wireless communication while being carried by an individual such as a wireless LAN terminal.

The mobile communication terminal is not only compact and lightweight due to steady development, but also has emerged as a multi-communication terminal with various functions such as mp3, camera and navigation, and is already becoming a necessity of modern man.

These recent mobile communication terminals can acquire and use various contents (music data, image data, etc.). In many cases, such contents are applied with DRM technology to protect copyright.

In order to use DRM technology-based content (hereinafter, DRM content) in a mobile communication terminal, the mobile communication terminal first accesses a content provider that provides the DRM content, metadata of the DRM content, DRM content, and The license must be downloaded. Here, the metadata is data in which information on the DRM content is stored, and the license is data of contents that specify an authentication key used to decrypt the encrypted content and a right to use the content (eg, the number and duration). If both the DRM content and the license are stored in the mobile terminal through this process, the user can use the DRM content.

As such, in the related art, in order to use the content to which the DRM technology is applied, it is inconvenient to obtain a separate license (ie, an authentication key) separately. do. In addition, in order to obtain a license, it is inconvenient to go through various complicated processes.

Accordingly, an object of the present invention is to provide a content transmission method and system using location information that can easily use content by using location information of a receiving terminal as an authentication key in transmitting content.

In addition, another object of the present invention is to provide a content transmission method and system using location information that can manage the copyright of the content using the location information of the receiving terminal.

The present invention for achieving the above object is a location information acquisition process of obtaining location information of the second terminal in the first terminal in response to the content transmission request, the transmission using the location information of the second terminal obtained by the first terminal An encoding process of encoding the requested content, a transmission process of transmitting the encoded content by the first terminal to the second terminal, and a decoding process of decoding the content transmitted using the location information from the second terminal; It is characterized by including.

In addition, the content delivery system according to the present invention is a first terminal for encoding and transmitting the corresponding content in response to the content transmission request, a second terminal receiving the content from the first terminal, and using the decoded content, and the first And a mobile communication network for transmitting information between the second terminal and the second terminal, wherein the first terminal encodes the content using location information of the second terminal, and the second terminal includes the first terminal. It characterized in that the content is decoded using the location information of the terminal.

In addition, the content transmission method of the mobile communication terminal according to the present invention comprises the steps of requesting the location information to the second terminal in response to the content transmission request, the process of obtaining the location information from the second terminal in accordance with the request, and the location Encoding the requested content using information, and transmitting the encoded content to the second terminal.

In addition, the content receiving method of the mobile communication terminal according to the present invention comprises the steps of obtaining the location information according to the location information request of the first terminal, transmitting the obtained location information to the first terminal, and the first Acquiring encoded content from a terminal, reacquiring the location information, and decoding the acquired content using the reacquired location information.

The method and system for transmitting content using location information according to the present invention encodes and decodes content using location information of a second terminal, which is a receiving terminal, as an authentication key. Therefore, the user has the advantage that no separate effort or complicated process is required to obtain the authentication key. In addition, the present invention uses the location information as the authentication key. Therefore, we propose a new content providing method and a copyright management method that can acquire the right to use the content according to the user's location.

Prior to the description of the present invention, the terms or words used in the specification and claims described below should not be construed as being limited to the ordinary or dictionary meanings, and the inventors should consider their own invention in the best way. For the purpose of explanation, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention on the basis of the principle that it can be appropriately defined as the concept of term. Therefore, the embodiments described in the present specification and the configuration shown in the drawings are only the most preferred embodiments of the present invention, and do not represent all of the technical idea of the present invention, and various equivalents may be substituted for them at the time of the present application. It should be understood that there may be water and variations.

In addition, in describing the embodiments, descriptions of technical contents which are well known in the technical field to which the present invention belongs and are not directly related to the present invention will be omitted. In addition, detailed description of components having substantially the same configuration and function will be omitted.

For the same reason, some components in the accompanying drawings are exaggerated, omitted, or schematically illustrated, and the size of each component does not entirely reflect the actual size.

On the other hand, the content (or content data) described in the present invention means digital content (Digital Contents), information or information, knowledge, database, etc. represented by code, text, voice, sound, image, video, etc. Technology or material) means data or information produced or processed in electronic form. In particular, it includes user-generated content (UCC (User Created Contents) or UGC (User Generated Contents)).

In addition, in the present embodiment, the location information is data generated from the location information receiver to be described later and refers to GPS coordinate information received from the GPS receiver.

In addition, in the present embodiment, a mobile communication terminal is classified into a calling terminal and a receiving terminal. Both the calling terminal and the receiving terminal are mobile communication terminals, and in the present embodiment, terminal names are classified according to whether contents are provided and received for convenience of description. That is, a mobile communication terminal (first terminal) providing content is called a calling terminal, and a mobile communication terminal (second terminal) receiving and using content is called a receiving terminal.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram schematically showing a content delivery system using location information according to an embodiment of the present invention.

Referring to FIG. 1, the content delivery system 10 using location information according to the present embodiment includes a calling terminal 100a, a receiving terminal 100b, a mobile communication network 50, and an LBS server 70. .

The mobile communication network 50 of this embodiment refers to all communication networks that relay signals so that the calling terminal 100a and the receiving terminal 100b can transmit and receive signals to each other. In the mobile communication network 50, various components such as a base station and a switching center generally exist, but this is a known technique and only in this embodiment is responsible for relaying signals, so a description thereof will be omitted.

The LBS server 70 is a server that provides a location based service. In the present embodiment, the LBS server 70 refers to a location based service system which is a known technology. The LBS server 70 communicates with the calling terminal 100a and the receiving terminal 100b through the mobile communication network 50, and sends them to the corresponding terminals 100a and 100b at the request of the respective terminals 100a and 100b. Provide location information.

The calling terminal 100a and the receiving terminal 100b are mobile communication terminals capable of communicating with each other via the mobile communication network 50. In addition, the calling terminal 100a transmits the encoded content to the receiving terminal 100b through the mobile communication network 50. The receiving terminal 100b receives the decoding content and then decodes the content. Therefore, the originating terminal 100a and the receiving terminal 100b include content converters 192a and 192b for encoding and decoding content, respectively.

 In addition, the receiving terminal 100b according to the present invention includes a location information receiving unit 110b. The location information receiver 110b is for acquiring information about a location where the mobile communication terminal 100b is currently located. In this embodiment, a GPS receiver is used. Therefore, although not shown, the content transmission system 10 according to the present embodiment includes a GPS satellite to which a GPS receiver transmits a GPS signal.

In addition, the calling terminal 100a and the receiving terminal 100b according to the present invention communicate with the LBS server 70 through the mobile communication network 50. Through this, the calling terminal 100a may obtain location information of the receiving terminal 100b.

On the other hand, in the embodiment described below, the originating terminal 100a does not require a location information receiver. However, for convenience of description, a case where both the calling terminal 100a and the receiving terminal 100b have the same configuration will be described as an example. That is, a case where both the calling terminal 100a and the receiving terminal 100b have the same configuration as the mobile communication terminal 100 shown in FIG. 2 will be described as an example. However, it is not limited thereto.

2 is a block diagram schematically illustrating a mobile communication terminal according to an embodiment of the present invention.

1 and 2, the mobile communication terminal 100 according to the present embodiment includes a wireless communication unit 130, an audio processing unit 140, a key input unit 160, a display unit 150, a storage unit 170, The location information receiver 110 and the controller 190 are included.

The wireless communication unit 130 performs a function of transmitting and receiving corresponding data for wireless communication of the mobile communication terminal 100. The wireless communication unit 130 may include an RF transmitter for upconverting and amplifying a frequency of a transmitted signal, and an RF receiver for low noise amplifying and downconverting a received signal. In addition, the wireless communication unit 130 may receive data through a wireless channel, output the data to the controller 190, and transmit data output from the controller 190 through a wireless channel.

The audio processor 140 may be configured as a coder (Coder / Decoder), and the codec may include a data codec for processing packet data and an audio codec for processing an audio signal such as voice. Therefore, the audio processor 140 converts the digital audio data received by the controller 190 through the wireless communication unit 130 into an analog audio signal through an audio codec and outputs the speaker to the speaker, and the analog audio signal input from the microphone. Is converted into digital audio data through an audio codec and provided to the controller 190.

The key input unit 160 receives a user's operation signal for controlling the mobile communication terminal 100 and transmits it to the controller 190. To this end, the key input unit 160 includes a control key (not shown) for controlling the operation of the mobile communication terminal 100 and a plurality of numeric keys (not shown) for inputting letters and numbers.

The display unit 150 displays data output from the controller 190 on the screen. Herein, the liquid crystal display (LCD) may be applied to the display unit 150. In this case, the display unit 150 may include an LCD controller, a memory capable of storing data, and an LCD display device. In this case, when the LCD is implemented using the touch screen method, the screen of the display unit 150 may be operated as an input unit.

The storage unit 170 includes a program memory and data memories. The program memory stores programs for controlling general operations of the mobile communication terminal 100. Data generated during program execution is stored in the data memory. In addition, the storage unit 170 according to the present embodiment stores the content data produced by the user or acquired from the outside. In addition, the storage unit 170 includes an authentication subject database 172 (hereinafter, an authentication subject DB) in which subjects that allow location information transmission are registered.

The authentication subject DB 172 includes a name field in which the names of the subjects are input and a number field in which terminal numbers (telephone numbers) of the subjects are stored. In the present embodiment, the location information is provided only to the calling terminal 100a registered in the authentication subject DB 172. Therefore, the user registers only those who want to provide location information to the authentication target DB 172.

In the present embodiment, a method of registering subjects with an additional subject DB 172 is described as an example, but is not limited thereto. That is, various methods may be used, such as adding an additional field to the phone book and providing location information to the target of the record when the corresponding field is selected.

The location information receiver 110 includes a GPS receiver (not shown), thereby obtaining coordinate information of the corresponding terminal. The location information receiver 110 receives a GPS coordinate signal of the current mobile communication terminal 100 from a GPS satellite and transmits the GPS coordinate signal to the location information processor 192 of the controller 190 to be described later.

The controller 190 performs an overall control operation of the mobile communication terminal 100. In addition, the controller 190 according to an embodiment of the present invention includes a location information processor 192 for obtaining and transmitting location information, and a content converter 194 for encoding and decoding content.

The location information processor 192 acquires the GPS coordinates by using the location information receiver 110 under the control of the controller 190. The location information processing unit 192 communicates with the LBS server 70 through the mobile communication network 50 and mutually transmits location information. In addition, the location information processing unit 192 obtains location information of a specific counterpart (ie, a receiving terminal) through the LBS server 70. In this case, it is possible only when the user is registered as an authentication target in the terminal of the counterpart.

The content converter 194 encodes and decodes the content according to a user's request. In the encoding process, the content converter 194 according to the present embodiment encodes the corresponding content by using the authentication key. Thus, the encoded content can only be used with the corresponding authentication key. In the present invention, the location information of the terminal receiving the content using the authentication key, that is, the GPS coordinates of the receiving terminal 100b is used. Therefore, the content converter 194 obtains the location information through the location information processor 192 and then encodes the corresponding content using the location information.

In addition, in the decoding process, the content converter 194 according to the present embodiment decodes the encoded content using the authentication key. In this case, the content converter 194 obtains the current location information of the mobile communication terminal 100 through the location information receiver 110 and then decodes the corresponding content using the location information.

The content converter 194 according to the present exemplary embodiment may use various codecs such as JPEG, Wavelet, mpeg2, mpeg4, H.263, and H.264 to encode and decode the content.

Next, a content transmission method using location information according to the present invention will be described in detail with reference to the following embodiments. The configuration of the content delivery system 10 and the mobile communication terminal 100 described above will also be clearer from the following description of the content delivery method.

3 is a flowchart schematically illustrating a content transmission method using location information according to the present invention. 4 is a flowchart schematically illustrating a content transmission method using location information of a calling terminal according to the present invention, and FIG. 5 is a flowchart schematically illustrating a content reception method using location information of a receiving terminal according to the present invention.

In the following description of the present embodiment, the components of the originating terminal 100a and the receiving terminal 100b all use the reference numbers of the mobile communication terminal 100 of FIG. 2. In this case, the components of the calling terminal 100a and the receiving terminal 100b may be distinguished from each other in the case of the calling terminal 100a by attaching a followed by a reference number, and the components of the receiving terminal 100b. In the case of, add b after the reference number.

A method of transmitting content using location information according to the present embodiment will be described with reference to FIGS. 1 to 5 as follows.

The content transmission method according to the present embodiment is first performed in step S10 in which power is applied to all mobile communication terminals 100a and 100b and enters an idle state according to a normal operation.

Subsequently, a process S11 is performed in which a content transmission request is input to the calling terminal 100a in a standby state. When the user of the calling terminal 100a requests the content transmission by manipulating the key input unit 160, the controller 190a recognizes this and receives the content to be transmitted and the telephone number of the receiving terminal 100b to be transmitted. Do this.

When the user operates the key input unit 160 to select the content to be transmitted and selects the number of the receiving terminal 100b to which the content is to be transmitted, the controller 190a then sends the location information processing unit 192a to the receiving terminal 100b. Request location information.

Subsequently, the location information processing unit 192a of the calling terminal 100a accesses the LBS server 70 through the mobile communication network 50 and performs a process S13 for requesting location information of the receiving terminal 100b. In response, the LBS server 70 receiving the location information of the receiving terminal 100b connects to the location information processing unit 192b of the receiving terminal 100b and performs an S14 process of requesting the location information of the receiving terminal 100b. .

The location information processing unit 192b of the receiving terminal 100b receiving the location information request performs an operation S15 of requesting authentication of the originating terminal 100a requesting the location information to the controller 190b. The controller 190b extracts the information (ie, the telephone number) of the calling terminal 100a and compares it with the data registered in the authentication subject DB 172b. If the telephone number of the calling terminal 100a is not registered in the authentication target DB 172b, the controller 190b recognizes the calling terminal 100a as an unauthenticated subject and refuses to provide location information. In this case, the controller 190b transmits a signal indicating that the location information cannot be provided through the location information processor 192b to the calling terminal 100a through the LBS server 70. On the other hand, when the phone number of the calling terminal 100a is registered in the authentication target DB 172b, the controller 190b recognizes the calling terminal 100a as an authenticated target and recognizes the location information through the process described below. Will be provided.

When the calling terminal 100a is an authentication target, the location information processing unit 192b of the receiving terminal 100b drives the location information receiving unit 110b to acquire GPS coordinates which are the location information of the current receiving terminal 100b. Do this. In this process, a situation may occur in which the location information of the reception terminal 100b cannot be obtained according to the location or the weather condition of the reception terminal 100b. In this case, the location information processing unit 192b of the receiving terminal 100b transmits a response including the content that the location information cannot be obtained to the LBS server 70. On the other hand, when the location information is obtained, the location information processing unit 192b of the receiving terminal 100b performs an S17 process of transmitting a response including the obtained location information to the LBS server 70.

The LBS server 70 receiving the location information of the receiving terminal 100b from the location information processing unit 192 of the receiving terminal 100b transmits it back to the location information processing unit 192 of the calling terminal 100a. Do this.

When the location information processing unit 192a of the calling terminal 100a acquires the location information of the receiving terminal 100b through the above process (S19), the location information processing unit 192a converts the acquired location information into the content conversion unit. Send to 194a.

On the other hand, when the receiving terminal 100b does not acquire the location information, the response transmitted through the LBS server 70 in step S18 is a response that does not include the location information is transmitted. In this case, the control unit 190a of the calling terminal 100a displays a message indicating that the position information of the receiving terminal 100b cannot be obtained on the display unit 150a to perform an S22 process of informing the user, and then transmits the content. End the process.

On the other hand, in step S18, if the location information of the receiving terminal 100b is included in the response and transmitted, then step S20 is performed to encode the content using the obtained location information.

The content converter 194a encodes the content selected by the user in step S12. At this time, the content conversion unit 194a encodes the corresponding content using the location information obtained in step S18 as an authentication key. The encoded content can thus be decoded only when using the corresponding authentication key.

When the encoding process of the content is completed, the control unit 190a performs a process S21 to transmit the encoded content to the receiving terminal (100b). The controller 190a may transmit the corresponding content to the mobile communication network 50 using various protocols. For example, MMS, E-mail, or the like can be used. It is also possible to transmit via Bluetooth technology when the other party is located at close range.

When the content is transmitted from the calling terminal 100a, the receiving terminal 100b performs a process S23 for receiving it through the mobile communication network 50.

The control unit 190b of the receiving terminal 100b that has received the content stores the received content in the storage unit 170b. Subsequently, the controller 190b performs a step S24 of checking whether the reception terminal 100b is set to automatically use (play) the received content.

If it is set to manual playback instead of automatic playback, the controller 190b does not play the content, and performs the step S30 of displaying a message on the display unit 150b indicating that the content has been received from the calling terminal 100a. After that, the content transmission process ends. However, if it is set to automatically play, the controller 190b performs a process for playing the corresponding content.

The controller 190b first decodes the received content. That is, the controller 190b requests the content converter 194b to decode the received content.

In order to decode the encoded content, an appropriate authentication key is required. Therefore, the content conversion unit 194b requests the location information processing unit 192b for location information of the current receiving terminal 100b.

Accordingly, the location information processing unit 192b acquires the location information of the current receiving terminal 100b by using the location information receiving unit 110b and performs the process of S25 of transmitting the location information to the content conversion unit 194b.

The content conversion unit 194b having obtained the location information performs the S26 process of decoding the encoded content using this as the authentication key.

In this process, when the location information is not suitable as the authentication key of the content, that is, the location information acquired in step S16 and transmitted to the calling terminal 100a and the location information obtained in step S25 are different, the location obtained in step S25. The information cannot be used as an authentication key of the corresponding content. This may occur when the receiving terminal 100b continues to move or when the user of the receiving terminal 100b moves to another place after performing the process S16. In this case, the receiving terminal 100b cannot use the received content, and can use the corresponding content only when the receiving terminal 100b moves to the same position as the position information acquired in step S16. When the corresponding content cannot be decoded using the location information acquired in step S25 as described above, the controller 190b displays a message indicating that the content cannot be decoded on the display unit 150b and performs a step S29 of informing the user. .

On the other hand, if the position information acquired in step S25 is the same as the position information obtained in step S16, the content converter 194 successfully decodes the received content (S27), and then displays the decoded content in the display unit 150b. In step S28, playback is performed.

The content according to the present invention uses a method of encoding using location information to protect the rights of the copyright holder such as DRM. Accordingly, the encoded content can be used only when there is an authentication key, but since the decoded content can be used without an authentication key, it is difficult to protect the rights of the content. Thus, when the encoded content is decoded, the decoded content may be temporarily stored in a buffer or the like, but not continuously. That is, only the content in the encoded state can be stored in the receiving terminal 100b according to the present embodiment, and the decoded content is immediately removed after playing.

Therefore, when the user wants to play the content again later, the receiving terminal 100b obtains the location information again and decodes the content by using it as an authentication key. However, the present invention is not limited to this method. That is, in another embodiment, various methods may be applied, such as by using a method of decoding content by decoding (that is, decoding and real time at the same time) and deleting the reproduced frames.

The content transmission method and system using the location information in the embodiment of the present invention performed through the above process encodes and decodes the content using the location information of the receiving terminal as an authentication key. Therefore, the user has an advantage that no extra effort or complicated process is required to obtain the authentication key. In addition, since location information is used as an authentication key, there is an advantage of providing a content usage method that can be used depending on the location.

On the other hand, the content transmission method and system using the location information according to the present invention is not limited to the embodiment, various modifications are possible by those skilled in the art within the technical idea of the present invention.

For example, in the present embodiment, a case of obtaining location information through GPS has been described as an example. However, the present invention is not limited thereto, and in another embodiment, a method of obtaining location information from a mobile communication service provider such as a base station without using an LSB server or a GPS receiver may be used. In this case, the calling terminal requests the mobile communication provider's location information of the receiving terminal, and the receiving terminal also acquires its location information through the mobile communication provider and uses it for decoding.

In addition, the present embodiment has been described taking the case of using the location information of the receiving terminal as an authentication key as an example. That is, the case where only the location information of the place where the receiving terminal is located is used as the only one authentication key. But it is not limited to this. That is, according to another embodiment of the present invention, after the calling terminal receives the location information of the receiving terminal, the authentication terminal applies the authentication key to the location information corresponding to the extended area by expanding the predetermined location centering on the received location information. It is also possible. In this case, if the receiving terminal is located in the extended area and uses the location information as the authentication key, the corresponding content can be decoded.

In addition, the present embodiment describes an example of transmitting content using location information in a mobile communication terminal. However, in addition to this, any electronic device capable of transmitting data through a mobile communication network or a wired communication network and obtaining location information may be widely applied.

1 is a view schematically showing a content delivery system using location information according to an embodiment of the present invention.

2 is a block diagram schematically illustrating a mobile communication terminal according to an embodiment of the present invention;

3 is a flowchart schematically illustrating a content transmission method using location information according to the present invention.

4 is a flowchart schematically illustrating a content transmission method using location information of a calling terminal according to the present invention;

5 is a flowchart schematically illustrating a content receiving method using location information of a receiving terminal according to the present invention.

Claims (20)

Obtaining location information for obtaining location information of a second terminal from a first terminal according to a content transmission request; An encoding process of encoding the content requested to be transmitted using location information of the second terminal acquired by the first terminal; A transmission process of transmitting, by the first terminal, the encoded content to the second terminal; and And decoding the content transmitted by the second terminal using the location information. The method of claim 1, wherein the obtaining of the location information comprises: Requesting location information from the first terminal to the second terminal, and And transmitting location information acquired by the second terminal to the first terminal. The method of claim 2, before performing the process of acquiring the location information, And identifying, by the second terminal, whether the first terminal is a terminal capable of receiving the location information. The method of claim 2, wherein the location information Method for transmitting content using location information, characterized in that the GPS (global positioning system) coordinates. The method of claim 2, wherein the encoding process, And encoding the content using the location information of the second terminal as an authentication key. The method of claim 2, wherein the transmission process, And transmitting the content encoded using any one of a MMS, an e-mail service, and Bluetooth. The method of claim 2, wherein the location information, Content delivery method using location information, characterized in that obtained by using a location-based system (LBS). The method of claim 2, wherein the decoding process, Receiving and storing the encoded content by the second terminal; Re-acquiring, by the second terminal, current location information of the second terminal; and And decoding the stored content using the re-acquired location information. The method of claim 8, wherein the decoding of the content comprises: Content decoding method using position information, characterized in that the process of decoding and displaying the content on the screen in real time. The method of claim 8, wherein the decoding of the content comprises: And decoding the content using the location information as an authentication key. A first terminal for encoding and transmitting corresponding content according to a content transfer request; A second terminal receiving the content from the first terminal, decoding the content and using the content; It comprises a mobile communication network for transmitting information between the second terminal and the second terminal, The first terminal encodes the content using location information of the second terminal, And the second terminal decodes the content using the location information of the second terminal. The method of claim 11, wherein the first terminal, And content information of the second terminal is obtained from the second terminal. The method of claim 11, wherein the location information Content transmission system using the location information, characterized in that the GPS coordinates. The method of claim 11, wherein the first terminal, And the content is encoded using location information of the second terminal as an authentication key. The method of claim 11, wherein the first terminal, Content delivery system using location information, characterized in that for transmitting the content encoded by using any one of MMS, E-mail service, or Bluetooth. The method of claim 11, wherein the second terminal, And when the encoded content is transmitted, obtain current location information of the second terminal, and decode the content using the obtained location information. The method of claim 16, wherein the second terminal, And the content is decoded using the location information as an authentication key. Requesting location information from the second terminal according to the content transmission request; Acquiring location information from the second terminal according to the request; Encoding the requested content using the location information, and And transmitting the encoded content to the second terminal. Acquiring the location information according to the location information request of the first terminal; Transmitting the obtained location information to the first terminal; Obtaining encoded content from the first terminal; Reacquiring the location information, and And decoding the acquired content using the re-acquired location information. The method of claim 18 or 19, wherein the location information, Content transmission system using the location information, characterized in that the GPS coordinates.

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