CTF competition video anti-cheating method and system in network target range

Abstract

The invention discloses a CTF competition video anti-cheating method and system in a network target range, and the method comprises the steps: displaying a button for starting a camera on a foreground page if a camera is required to be forcibly started before a participant enters a competition of the participant; after the cameras are turned on, monitoring whether the cameras of the participants are turned on or not, and if not, enabling the participants not to participate in the competition; when the participants answer questions after entering the competition details, regularly obtaining the starting state of the cameras of the participants; if yes, automatically skipping to a match list page, and continuing the match only by restarting the camera, and if yes, regularly storing the screen recording video according to the frequency value in the configuration parameters; and when the administrator performs background competition operation and maintenance, displaying the stored video record on the camera management page for the administrator to download and check. According to the invention, the safety of the competition platform and the resistance and detection capability of the competition platform to cheating behaviors can be improved.

Description

Technical Field

[0001] The present invention relates to an anti-cheating method and system for CTF competition videos in a network shooting range, belonging to the technical field of computer software and network security. Background Art

[0002] Cyber ​​Range is a technology or product based on virtualization technology that simulates and reproduces the operating status and operating environment of network architecture, system equipment, and business processes in real cyberspace, so as to more effectively realize learning, research, testing, competition, exercises and other behaviors related to network security, thereby improving the network security confrontation level of personnel and institutions.

[0003] CTF (Capture The Flag) is generally translated into Chinese as a flag-grabbing competition. In the field of network security, it refers to a form of competition among network security technicians. CTF originated from the 1996 DEFCON Global Hacker Conference, replacing the previous method of hackers launching real attacks against each other to compete in technology. It has become a popular competition form in the global network security circle.

[0004] There are many participants in the CTF competition. Implementing full manual proctoring will result in a waste of manpower, high costs, and ineffective results. Traditional camera monitoring and proctoring also requires real-time monitoring by someone in the background, and the entire exam period must be monitored, resulting in a waste of resources. If the examinee intentionally turns off the camera and the real-time monitoring cannot see it, it will be impossible to respond quickly to on-site problems. Summary of the invention

[0005] Purpose of the invention: In view of the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide an anti-cheating method and system for CTF competition videos in a network shooting range, so as to improve the security of the competition platform, as well as the resistance and detection capabilities of the competition platform to cheating.

[0006] Technical solution: To achieve the above-mentioned invention object, the present invention adopts the following technical solution:

[0007] A method for anti-cheating in a CTF competition video in a network shooting range comprises the following steps:

[0008] Before a contestant enters his or her own competition, the backend interface is called to obtain the administrator's configuration parameters in the background. If the camera needs to be turned on forcibly, a button to turn on the camera is displayed on the front page;

[0009] After the camera is turned on, the camera status is monitored. When the camera is turned on, the backend interface is called regularly at a set first time interval to write the contestant ID and the competition ID of the contestant who turned on the camera to the backend cache; the backend periodically clears the expired cache information at a set second time interval, and the second time interval is greater than the first time interval;

[0010] When a contestant clicks the button to enter the competition, the backend interface is called to obtain the status of the camera. Only when the camera is turned on can the contestant enter the competition question answering page;

[0011] After the contestants enter the competition details and answer questions, they call the backend interface to obtain the status of the contestant's camera in real time. If it is not turned on, it will automatically jump to the competition list page and turn the camera back on to continue the competition. If it is turned on, the screen recording video will be stored regularly according to the frequency value in the configuration parameters.

[0012] If the recording time in the configuration parameters is exceeded, the recording will end, otherwise the screen recording video will continue to be stored regularly;

[0013] When the administrator is operating the game in the background, the stored video records will be displayed on the camera management page for the administrator to download and view.

[0014] Furthermore, the process of camera screen recording includes:

[0015] Define the MediaUtils object for processing device media, including the getUserMedia method for getting the media stream and the closeStream method for closing the media stream;

[0016] When the contestant clicks the camera button, the MediaUtils.getUserMedia method is called to obtain the current device media stream; if the acquisition fails, a prompt will be given;

[0017] If the media stream is obtained, use the MediaRecorde.isTypeSupported method to obtain the supported video mimeType type, and use the MediaRecorder(stream,mimeTyp) method to record the obtained media stream;

[0018] Use the video tag on the page to bind the video.play() method to play the real-time screen recording and display the real-time game screen of the contestants; use the MediaRecorde.ondataavailable method to process the played data and generate a binary file stream from the media stream;

[0019] Convert binary file stream into video format file;

[0020] Determine whether recording is started or ended. If recording is started, call the start recorder method. If recording is ended, call the stop recorder method and close the media stream.

[0021] Furthermore, the process of storing the screen recording video includes:

[0022] During recording, the frequency value is set, and according to the start and end recording times start_time and end_time, and the generated video file, the video upload interface is called according to the frequency time period to generate the file path. After the file path is generated, the video file addition interface is called again to store the screen recording file.

[0023] If the recording time during the recording process exceeds the set recording end time end_time, the recording will end automatically.

[0024] Furthermore, the front end determines whether the camera is turned on by determining whether the device media stream can be obtained, thereby monitoring the camera status. If the camera is not turned on, the back end write interface is stopped from being called.

[0025] Furthermore, the backend determines whether the contestant has turned on the camera. The process includes:

[0026] Extract the participant ID and competition ID;

[0027] Query the game ID and participant ID records in the cache. If they exist, the camera is considered to be turned on, otherwise it is considered that the camera is not turned on.

[0028] A CTF competition video anti-cheating system in a network shooting range, comprising:

[0029] The initialization module is used to obtain the administrator's configuration parameters in the background before the contestants enter their own competitions. If the camera is required to be turned on by force, a button to turn on the camera will be displayed on the front page;

[0030] The camera status refresh module is used to monitor the camera status after the camera is turned on, and to call the back-end interface at a set first time interval to write the contestant ID and the competition ID of the contestant who turned on the camera to the back-end cache when the camera is turned on; the back-end periodically clears the expired cache information at a set second time interval, and the second time interval is greater than the first time interval;

[0031] The competition entry control module is used to call the backend interface to obtain the status of the camera when the contestant clicks the enter competition button. Only when the camera is turned on can the contestant enter the competition answering page;

[0032] The timed monitoring and recording module is used to call the backend interface to obtain the camera status of the contestants in real time while answering questions after entering the competition details. If it is not turned on, it will automatically jump to the competition list page and restart the camera to continue the competition. If it is turned on, the screen recording video will be stored regularly according to the frequency value in the configuration parameters. If the recording time in the configuration parameters is exceeded, the recording will end, otherwise the screen recording video will continue to be stored regularly.

[0033] The backstage operation and maintenance module is used by administrators to display stored video records on the camera management page for administrators to download and view when they are performing backstage competition operation and maintenance.

[0034] A computer system includes a memory, a processor, and a computer program / instruction stored in the memory and executable on the processor. When the computer program / instruction is executed by the processor, the steps of the anti-cheating method for CTF competition videos in a network shooting range are implemented.

[0035] A computer program product includes a computer program / instruction, wherein when the computer program / instruction is executed by a processor, the steps of the anti-cheating method for CTF competition videos in a network shooting range are implemented.

[0036] Beneficial effects: Compared with the prior art, the present invention has the following advantages: 1. Management personnel can view the competition videos of contestants in real time, saving space and labor costs; 2. By setting the time with dynamic frequency, the competition videos of contestants in different time periods can be viewed, and timely responses can be made to on-site situations to ensure the fairness and justice of the competition; 3. Real-time video storage provides the basis and evidence for cheating; 4. If a contestant turns off the camera during the answering process, a timely response can be made, and the contestant cannot be allowed to continue answering questions and must exit the competition. More emphasis is placed on real-time response and processing capabilities, and measures can be taken quickly after cheating is discovered to ensure the fairness and justice of the competition. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 Schematic diagram of a flow chart of an embodiment of the present invention.

[0038] Figure 2 The figure is a flow chart of starting camera screen recording and storing video in an embodiment of the present invention.

[0039] Figure 3 The figure is a flow chart of determining whether a contestant has turned on their camera in an embodiment of the present invention.

[0040] Figure 4 This is an example diagram of a game parameter configuration page in an embodiment of the present invention.

[0041] Figure 5 This is an example diagram of a match list page in an embodiment of the present invention.

[0042] Figure 6 This is an example diagram of a video recording function inspection page in an embodiment of the present invention.

[0043] Figure 7 This is an example diagram of a match list page in an embodiment of the present invention (prompting that the camera is not turned on).

[0044] Figure 8 This is an example diagram of a match details page in an embodiment of the present invention.

[0045] Fig. 9 This is an example diagram of a page for returning to a match list in an embodiment of the present invention.

[0046] Fig.10 This is an example diagram of a camera management page in an embodiment of the present invention. DETAILED DESCRIPTION

[0047] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments.

[0048] like Figure 1 As shown, an anti-cheating method for CTF competition videos in a network range disclosed in an embodiment of the present invention mainly comprises the following steps:

[0049] 1. The administrator sets parameters in the background flag-grabbing competition operation and maintenance, forces the camera parameter enable to be turned on, and sets the frequency parameter frequency: stores the screen recording video regularly within the set frequency time range, with the start time start_time and end time end_time parameters, and records the screen within the starting time period.

[0050] 2. After logging into the system and before entering their own competition, contestants should first obtain the configuration parameters of the background capture the flag competition set by the administrator through the public / jeopardy_race / race / d9b0b87bfd684fa640b081c6de1c0063 / video / config / interface.

[0051] 3. If enable is true, a button to turn on the camera will be displayed on the page. Participants must first enter the camera turn-on page to turn on the camera.

[0052] 4. After the camera is turned on, call the callCamera method. If the camera is turned on successfully, the recordtype field is returned with a value of BEGIN. After the camera is turned on successfully, call / web / jeopardy_race / race / d9b0b87bfd684fa640b081c6de1c0063 / video / status / refresh at a fixed time (5 seconds), pass the contestant ID and game ID to the interface, and store them in the backend cache to regularly refresh the contestant's camera on status and monitor the contestant's camera on status. The contestant ID and game ID information in the cache will be deleted every 10 seconds according to the timestamp when it was stored, so it is necessary to store the contestant ID and game ID information at a fixed time of 5 seconds to update the status of the contestant's camera in real time. When the contestant turns off the camera or stops recording, the recordtype value changes to END, and the call to this interface stops.

[0053] 5. When the contestant clicks the button to enter the competition, he must first call

[0054] web / jeopardy_race / race / d9b0b87bfd684fa640b081c6de1c0063 / video / status / get / , get the status of the camera. Only when the returned status is true can you enter the competition. Otherwise, the page will prompt "Camera is not turned on" and participants need to go to the page to turn on the camera.

[0055] 6. After the contestants enter the competition details and answer the questions, a call is made every 5 seconds to web / jeopardy_race / race / d9b0b87bfd684fa640b081c6de1c0063 / video / status / get / to obtain the camera status of the contestants in real time.

[0056] 7. If status is false, it means the camera is not turned on. The contestant cannot continue answering questions and will automatically jump to the competition list page. The contestant needs to re-enter the camera turn-on page and turn the camera back on to continue the competition. If status is true, it means the camera is on. Then, according to the value of the frequency parameter, the interface / admin / video_record_info_race / add for storing screen recording videos is called regularly.

[0057] 8. Administrator passes

[0058] / admin / video_record_info_race / page?per_page=10&page=1&match_id=d9b0b87bfd684fa640b081c6de1c0063 interface to obtain screen recording data, and in the background competition operation and maintenance, the camera management page can see the stored video records for download and viewing.

[0059] In the above steps, the process of starting camera recording and storing video is as follows: Figure 2 As shown, the details are as follows:

[0060] 1. First define the MediaUtils object for processing device media, including the getUserMedia method for obtaining the media stream and the closeStream method for closing the media stream.

[0061] 2. When the contestant clicks the camera button, the MediaUtils.getUserMedia method is called to obtain the current device media stream.

[0062] 3. If the acquisition fails, please check whether the current device supports the recording function.

[0063] 4. If a media stream is obtained, use the MediaRecorde.isTypeSupported method to obtain the supported video mimeType type, and use the MediaRecorder(stream,mimeTyp) method to record the obtained media stream.

[0064] 5. Use the video tag on the page to bind the video.play() method to play the real-time screen recording and display the real-time game screen of the contestants.

[0065] 6. Process the playback data according to the MediaRecorde.ondataavailable method, and generate a binary file stream from the media stream according to the Blob method.

[0066] 7. Use the File method to convert the binary file stream into an mp4 format file.

[0067] 8. Determine whether the recording is started or ended according to the recordtype field. If it is BEGIN, it means the recording has started, and the mediaRecorder.start() method is called to start the recording. If it is END, it means the end, and the mediaRecorder.stop() method is called to stop the recording, and the media stream MediaUtils.closeStream(mediaStream) method is closed.

[0068] 9. During recording, according to the set frequency, start and end recording time start_tim, end_time, and the generated mp4 file, call / common / video_upload according to the frequency time period to generate the file path.

[0069] 10. After generating the file path, continue to call the interface / admin / video_record_info_race / add to store the screen recording file.

[0070] 11. According to the set recording time period, start_time and end_time, if the recording time exceeds the set recording end time end_time, the stopRecord method will be called to automatically end the recording.

[0071] The names of the interfaces involved in the above steps can be adjusted according to actual project preferences. Some front-end code examples are provided below.

[0072] The code that defines the MediaUtils object that handles device media streams is as follows:

[0073]

[0074]

[0075]

[0076] The code for opening the camera is as follows:

[0077]

[0078]

[0079] The recording code and timed storage code are as follows:

[0080]

[0081]

[0082]

[0083] }

[0084] },

[0085] Combine the following Figures 4 to 10 The interface operation process of the embodiment of the present invention is illustrated.

[0086] 1. The administrator configures the competition parameters on the background capture the flag management page, configures the camera parameters, sets the dynamic frequency setting parameters, and the time period setting parameters for video recording, such as Figure 4 shown.

[0087] 2. Before entering the competition on the front page, participants need to click the camera-on button to enter the camera-on page. Figure 5 .

[0088] 3. Enter the camera opening page and click to open the camera. Please check whether the current device supports the video recording function. Only after the camera function of the current device is turned on can real-time screen recording be performed. Figure 6 .

[0089] 4. After turning on the camera, participants can return to the competition list page and click Enter Competition to start answering questions. If the camera function is not turned on, participants cannot enter the competition and will be prompted that the camera is not turned on. Figure 7 .

[0090] 5. After turning on the camera, the contestants enter the details page to answer questions and record the screen in real time on the page where the camera is turned on. Figure 8 .

[0091] 6. If a contestant clicks the "Close Camera" button or closes the page during the competition, the recording will stop and the contest page will be directly exited. The contest list page will be returned. The contestant needs to turn on the camera again to enter the competition page again. Fig. 9 .

[0092] 7. During the competition, the dynamic frequency parameters set by the administrator before the competition will automatically generate screen recordings within the set parameter time period. The administrator can download and view the team and participants at any time to determine whether they are cheating. Fig.10 .

[0093] The embodiment of the present invention discloses an anti-cheating system for CTF competition videos in a network shooting range, comprising: an initialization module, used for obtaining configuration parameters of an administrator in the background before a contestant enters his / her own competition, and if a camera is required to be forcibly turned on, a button for turning on the camera is displayed on a foreground page; a camera status refresh module, used for monitoring the camera status after the camera is turned on, and when the camera is turned on, calling a back-end interface at a set first time interval to write the contestant ID and the competition ID who turned on the camera into the back-end cache; the back-end regularly clears expired cache information at a set second time interval, and the second time interval is greater than the first time interval; a competition entry control module, used for the contestant to click on the control button to enter the game; When the enter competition button is pressed, the backend interface is called to obtain the status of the camera. Only when it is turned on can the competition answering page be entered; the timed monitoring and recording module is used for contestants to enter the competition details and answer questions while calling the backend interface to obtain the camera status of the contestants in real time; if it is not turned on, it will automatically jump to the competition list page and restart the camera to continue the competition. If it is turned on, the screen recording video will be stored at a fixed time according to the frequency value in the configuration parameters; if the recording time in the configuration parameters is exceeded, the recording will be ended, otherwise the screen recording video will continue to be stored at a fixed time; the background operation and maintenance module is used for administrators to display the stored video records on the camera management page for administrators to download and view when performing background competition operation and maintenance.

[0094] In the timed monitoring and recording module, the process of camera screen recording includes:

[0095] Define the MediaUtils object for processing device media, including the getUserMedia method for getting the media stream and the closeStream method for closing the media stream;

[0096] When the contestant clicks the camera button, the MediaUtils.getUserMedia method is called to obtain the current device media stream; if the acquisition fails, a prompt will be given;

[0097] If the media stream is obtained, use the MediaRecorde.isTypeSupported method to obtain the supported video mimeType type, and use the MediaRecorder(stream,mimeTyp) method to record the obtained media stream;

[0098] Use the video tag on the page to bind the video.play() method to play the real-time screen recording and display the real-time game screen of the contestants; use the MediaRecorde.ondataavailable method to process the played data, and use the Blob method to generate a binary file stream from the media stream;

[0099] Use the File method to convert the binary file stream into a video format file;

[0100] Determine whether recording is started or ended. If recording is started, call the start recorder method. If recording is ended, call the stop recorder method and close the media stream.

[0101] In the timed monitoring and recording module, the process of storing screen recording video includes:

[0102] During recording, the frequency value is set, and according to the start and end recording times start_time and end_time, and the generated video file, the video upload interface is called according to the frequency time period to generate the file path. After the file path is generated, the video file addition interface is called again to store the screen recording file.

[0103] If the recording time during the recording process exceeds the set recording end time end_time, the recording will end automatically.

[0104] The front end determines whether the camera is turned on by determining whether the device media stream can be obtained to monitor the camera status. If the camera is not turned on, the back end write interface is stopped. Figure 3 The backend determines whether the contestant has turned on the camera. The process includes:

[0105] Extract the participant ID and competition ID;

[0106] Query the game ID and participant ID records in the cache. If they exist, the camera is considered to be turned on, otherwise it is considered that the camera is not turned on.

[0107] A computer system disclosed in an embodiment of the present invention includes a memory, a processor, and a computer program / instruction stored in the memory and executable on the processor. When the computer program / instruction is executed by the processor, the steps of the anti-cheating method for CTF competition videos in a network shooting range are implemented.

[0108] A computer program product disclosed in an embodiment of the present invention includes a computer program / instruction, and when the computer program / instruction is executed by a processor, the steps of the anti-cheating method for CTF competition videos in a network shooting range are implemented.

Claims

1. A method for anti-cheating in CTF competition videos in a network shooting range, characterized in that: The steps include: Before a contestant enters his or her own competition, the backend interface is called to obtain the administrator's configuration parameters in the background. If the camera needs to be turned on forcibly, a button to turn on the camera is displayed on the front page; After the camera is turned on, the camera status is monitored. When the camera is turned on, the backend interface is called regularly at a set first time interval to write the contestant ID and the competition ID of the contestant who turned on the camera to the backend cache; the backend periodically clears the expired cache information at a set second time interval, and the second time interval is greater than the first time interval; When a contestant clicks the button to enter the competition, the backend interface is called to obtain the status of the camera. Only when the camera is turned on can the contestant enter the competition question answering page; After the contestants enter the competition details and answer questions, they call the backend interface to obtain the status of the contestant's camera in real time. If it is not turned on, it will automatically jump to the competition list page and turn the camera back on to continue the competition. If it is turned on, the screen recording video will be stored regularly according to the frequency value in the configuration parameters. If the recording time in the configuration parameters is exceeded, the recording will end, otherwise the screen recording video will continue to be stored regularly; When the administrator is operating the game in the background, the stored video records will be displayed on the camera management page for the administrator to download and view.

2. According to claim 1, a method for anti-cheating in a CTF competition video in a network shooting range is characterized in that: The process of camera screen recording includes: Define the MediaUtils object for processing device media, including the getUserMedia method for getting the media stream and the closeStream method for closing the media stream; When the contestant clicks the camera button, the MediaUtils.getUserMedia method is called to obtain the current device media stream; if the acquisition fails, a prompt will be given; If the media stream is obtained, use the MediaRecorde.isTypeSupported method to obtain the supported video mimeType type, and use the MediaRecorder(stream,mimeTyp) method to record the obtained media stream; Use the video tag on the page to bind the video.play() method to play the real-time screen recording and display the real-time game screen of the contestants; use the MediaRecorde.ondataavailable method to process the played data and generate a binary file stream from the media stream; Convert binary file stream into video format file; Determine whether recording is started or ended. If recording is started, call the start recorder method. If recording is ended, call the stop recorder method and close the media stream.

3. According to claim 1, the anti-cheating method for CTF competition videos in a network shooting range is characterized in that: The process of storing screen recording videos includes: During recording, the frequency value is set, and according to the start and end recording times start_time and end_time, and the generated video file, the video upload interface is called according to the frequency time period to generate the file path. After the file path is generated, the video file addition interface is called again to store the screen recording file. If the recording time during the recording process exceeds the set recording end time end_time, the recording will end automatically.

4. According to claim 1, the anti-cheating method for CTF competition videos in a network shooting range is characterized in that: The front end determines whether the camera is turned on by determining whether the device media stream can be obtained to monitor the camera status. If the camera is not turned on, the back end write interface is stopped.

5. According to claim 1, the anti-cheating method for CTF competition videos in a network shooting range is characterized in that: The backend process of determining whether the contestant has turned on the camera includes: Extract the participant ID and competition ID; Query the game ID and participant ID records in the cache. If they exist, the camera is considered to be turned on, otherwise it is considered that the camera is not turned on.

6. A CTF competition video anti-cheating system in a network shooting range, characterized in that: include: The initialization module is used to obtain the administrator's configuration parameters in the background before the contestants enter their own competitions. If the camera is required to be turned on by force, a button to turn on the camera will be displayed on the front page; The camera status refresh module is used to monitor the camera status after the camera is turned on, and to call the back-end interface at a set first time interval to write the contestant ID and the competition ID of the contestant who turned on the camera to the back-end cache when the camera is turned on; the back-end periodically clears the expired cache information at a set second time interval, and the second time interval is greater than the first time interval; The competition entry control module is used to call the backend interface to obtain the status of the camera when the contestant clicks the enter competition button. Only when the camera is turned on can the contestant enter the competition answering page; The timed monitoring and recording module is used to call the backend interface to obtain the camera status of the contestants in real time while answering questions after entering the competition details. If it is not turned on, it will automatically jump to the competition list page and restart the camera to continue the competition. If it is turned on, the screen recording video will be stored regularly according to the frequency value in the configuration parameters. If the recording time in the configuration parameters is exceeded, the recording will end, otherwise the screen recording video will continue to be stored regularly. The backstage operation and maintenance module is used by administrators to display stored video records on the camera management page for administrators to download and view when they are performing backstage competition operation and maintenance.

7. The anti-cheating system for CTF competition videos in a network shooting range according to claim 6, characterized in that: In the timed monitoring and recording module, the process of camera screen recording includes: Define the MediaUtils object for processing device media, including the getUserMedia method for getting the media stream and the closeStream method for closing the media stream; When the contestant clicks the camera button, the MediaUtils.getUserMedia method is called to obtain the current device media stream; if the acquisition fails, a prompt will be given; If the media stream is obtained, use the MediaRecorde.isTypeSupported method to obtain the supported video mimeType type, and use the MediaRecorder(stream,mimeTyp) method to record the obtained media stream; Use the video tag on the page to bind the video.play() method to play the real-time screen recording and display the real-time game screen of the contestants; use the MediaRecorde.ondataavailable method to process the played data and generate a binary file stream from the media stream; Convert binary file stream into video format file; Determine whether recording is started or ended. If recording is started, call the start recorder method. If recording is ended, call the stop recorder method and close the media stream.

8. The anti-cheating system for CTF competition videos in a network shooting range according to claim 6, characterized in that: In the timed monitoring and recording module, the process of storing screen recording video includes: During recording, the frequency value is set, and according to the start and end recording times start_time and end_time, and the generated video file, the video upload interface is called according to the frequency time period to generate the file path. After the file path is generated, the video file addition interface is called again to store the screen recording file. If the recording time during the recording process exceeds the set recording end time end_time, the recording will end automatically.

9. A computer system comprising a memory, a processor, and a computer program / instruction stored in the memory and executable on the processor, characterized in that: When the computer program / instructions are executed by the processor, the steps of the anti-cheating method for CTF competition videos in a network shooting range are implemented according to any one of claims 1-5.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by the processor, the steps of the anti-cheating method for CTF competition videos in a network shooting range are implemented according to any one of claims 1-5.

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