Media distribution system, communication system, distribution control device, distribution control method and program

Abstract

To solve the following problem of conventional arts: in the distribution of media information among a plurality of sites, if a reserved bandwidth used across the sites that share the media information exceeds a predetermined bandwidth, the transmission and reception quality of the media information to be shared is difficult to maintain.SOLUTION: A distribution control apparatus 7 is configured to: search a media distribution server management DB 7002 using media distribution server identification information as a search key, to read a corresponding maximum reserved bandwidth, and calculate a difference from the maximum reserved bandwidth (step S104); select and assign a media distribution server, based on the available bandwidth calculated (step S105); transmit a connection request to the media distribution server 9 capable of distributing media information to a communication apparatus A at a site A (step S125); and transmit, by the distributable media distribution server 9, the media information of a predetermined site in response to a request from a communication apparatus at another site (step S147).SELECTED DRAWING: Figure 19A

Description

[Technical Field]

[0001] The present invention relates to a media distribution system, a communication system, a distribution control device, a distribution control method, and a program. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there have been systems that transmit and receive media information such as video data and audio data in real time between a plurality of locations.

[0003] For example, a technique is known for allocating bandwidth used to receive each video so that the bandwidth used to receive the video a user is gazing at in a video conferencing system is larger than the bandwidth used to receive other videos (see, for example, Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0004] However, with conventional technology, when distributing media information between multiple locations, if the reserved bandwidth used between the locations sharing the media information exceeds a specified bandwidth, the transmission and reception quality of the shared media information cannot be maintained. [Means for solving the problem]

[0005] In order to solve the above-mentioned problems, the invention of claim 1 provides a media distribution system including one or more media distribution servers that distribute predetermined media information to communication devices at each base, and a distribution control device that controls distribution between the communication devices at each base and the media distribution server, the media distribution server includes one or more rooms, and one or more locations that share the predetermined media information are connected to the rooms;The delivery control device comprises an allocation means for allocating a media delivery server selected based on a reserved bandwidth for the delivery required by a predetermined media delivery server and a maximum reserved bandwidth available to the predetermined media delivery server as a media delivery server capable of delivering to a communication device of each of the bases at a predetermined assembly point including one or more bases sharing the predetermined media information, and a transmission means for transmitting a connection response as a response to a connection request to a communication device of a predetermined base included in the predetermined assembly point that has transmitted a connection request to connect to the allocated media delivery server capable of delivering, and the media delivery server capable of delivering comprises a transmission means for transmitting the predetermined media information transmitted by the communication device of the predetermined base based on the connection response transmitted by the delivery control device to a communication device of another base included in the predetermined assembly point. The media distribution server controls the upload bandwidth up(i) and the download bandwidth down(i,j) of an arbitrary site i for the predetermined media information of the arbitrary site i, when the room reservation bandwidth BR of the room is given, so that the following formula (1) holds for the upload bandwidth up(i) and the download bandwidth down(i,j) of the site j for the predetermined media information of the arbitrary site i: The present invention provides a media distribution system characterized by: BR≧Σup(i)+Σdown(i,j) ...Equation (1) [Effects of the Invention]

[0006] As described above, according to the present invention, when media information is distributed between multiple locations, it is possible to maintain the transmission and reception quality of the shared media information even if the reserved bandwidth used between the locations sharing the media information exceeds a predetermined bandwidth. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 10 is a diagram illustrating an example of the relationship between dynamic media control and reserved bandwidth in a plurality of locations. [Figure 2] FIG. 1 is a diagram illustrating an example of a concept of a room. [Figure 3] FIG. 1 is a diagram illustrating an example of the overall configuration of a communication system. [Figure 4] FIG. 2 is a diagram illustrating an example of a hardware configuration of the imaging device. [Figure 5] FIG. 2 is a diagram illustrating an example of a hardware configuration of a display device, an information processing device, and a communication terminal. [Figure 6]FIG. 2 is a diagram illustrating an example of a hardware configuration of the imaging device. [Figure 7] FIG. 2 is a diagram illustrating an example of the hardware configuration of an application server, a distribution control device, and a media distribution server. [Figure 8] FIG. 1 illustrates an example of a functional configuration of a communication system. [Figure 9] FIG. 10 is a conceptual diagram illustrating an example of a client management table. [Figure 10] FIG. 10 is a conceptual diagram illustrating an example of a media distribution server management table. [Figure 11] FIG. 10 is a conceptual diagram illustrating an example of a room management table. [Figure 12] FIG. 10 is a conceptual diagram illustrating an example of an access token management table. [Figure 13] FIG. 1 illustrates an example of a functional configuration of a communication system. [Figure 14] FIG. 10 is a conceptual diagram illustrating an example of a client management table. [Figure 15] FIG. 1 illustrates an example of a functional configuration of a communication system. [Figure 16] FIG. 10 is a sequence diagram illustrating an example of a room generation process. [Figure 17A] FIG. 10 is a sequence diagram showing an example of a connection process from a site A. [Figure 17B] FIG. 10 is a sequence diagram showing an example of a connection process from a site A. [Figure 18A] FIG. 10 is a sequence diagram showing an example of a connection process from a site B. [Figure 18B] FIG. 10 is a sequence diagram showing an example of a connection process from a site B. [Figure 18C] FIG. 10 is a sequence diagram showing an example of a connection process from a site B. [Figure 19A] FIG. 10 is a sequence diagram showing an example of a connection process from a site C. [Figure 19B] 10 is a flowchart illustrating an example of a process of determining whether to change the allocation of a media distribution server when the reserved bandwidth for a room is changed. [Figure 19C] FIG. 10 is a sequence diagram showing an example of a connection process from a site C. [Figure 19D] FIG. 10 is a sequence diagram showing an example of a connection process from a site C. [Figure 20] FIG. 10 is a sequence diagram illustrating an example of a reconnection process at site A. [Figure 21A] FIG. 10 is a sequence diagram illustrating an example of a reconnection process at site B. [Figure 21B] FIG. 10 is a sequence diagram illustrating an example of a reconnection process at site B. [Figure 22] (A) is an example of media information displayed on a display device, (B) is an example of media information displayed on an information processing device, and (C) is an example of a screen display showing an example of media information displayed on a communication terminal. [Figure 23] FIG. 10 is a conceptual diagram illustrating an example of a room management table according to the second embodiment. [Figure 24A] FIG. 11 is a sequence diagram showing an example of a connection process from a location C according to the second embodiment. [Figure 24B] 10 is a flowchart showing an example of allocation change determination processing of a media distribution server when a room reserved bandwidth is changed according to the second embodiment. [Figure 24C] FIG. 11 is a sequence diagram showing an example of a connection process from a location C according to the second embodiment. [Figure 24D] 10 is a diagram showing an example of a standby screen display at a location C according to the second embodiment. [Figure 24E] FIG. 11 is a sequence diagram showing an example of a connection process from a location C according to the second embodiment. [Figure 24F] FIG. 11 is a sequence diagram showing an example of a connection process from a location C according to the second embodiment. [Figure 25] FIG. 11 is a sequence diagram illustrating an example of a reconnection process at a site A according to the second embodiment. [Figure 26A] FIG. 11 is a sequence diagram illustrating an example of a reconnection process at a site B according to the second embodiment. [Figure 26B] FIG. 11 is a sequence diagram illustrating an example of a reconnection process at a site B according to the second embodiment. [Figure 27] FIG. 10 is a diagram illustrating an example of the overall configuration of a communication system according to a third embodiment. [Figure 28A] FIG. 13 is a sequence diagram showing an example of a connection process from a location C according to the third embodiment. [Figure 28B] 13 is a flowchart showing an example of allocation change determination processing of a media distribution server when a room reserved bandwidth is changed according to the third embodiment. [Figure 28C] FIG. 13 is a sequence diagram showing an example of a connection process from a location C according to the third embodiment. [Figure 29] FIG. 13 is a sequence diagram illustrating an example of a reconnection process at a location H according to the third embodiment. [Figure 30] FIG. 13 is a sequence diagram illustrating an example of a standby state inquiry process from a base C according to the third embodiment. [Figure 31] FIG. 13 is a sequence diagram illustrating an example of a reconnection process at a location I according to the third embodiment. [Figure 32] FIG. 13 is a sequence diagram showing another example of the standby state inquiry process from the site C according to the third embodiment. [Figure 33] FIG. 13 is a sequence diagram illustrating an example of a reconnection process at a site A according to the third embodiment. [Figure 34A] FIG. 13 is a sequence diagram illustrating an example of a reconnection process at a site B according to the third embodiment. [Figure 34B] FIG. 13 is a sequence diagram illustrating an example of a reconnection process at a site B according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are given the same reference numerals, and if there are overlapping parts, their description will be omitted.

[0009] [First embodiment] The first embodiment will be described with reference to FIGS.

[0010] [Prerequisite technology for media information distribution] <Relationship between Dynamic Media Control and Reserved Bandwidth> Figure 1 shows an example of the relationship between dynamic media control and reserved bandwidth at multiple locations. As shown in Figure 1, consider the case where there is a media distribution server that receives specified media information from locations 1, 2, and 3 and distributes it to each location. When this media distribution server is given a room reserved bandwidth BR for a "room" (described later) at each location, it controls up(i) and down(i,j) so that the following (Equation 1) holds for the upload bandwidth up(i) of any location i and the download bandwidth down(i,j) of any location j for the media information at location j.

[0011]

number

[0012] In a system consisting of multiple media delivery servers, a media delivery server that can accommodate the specified room reserved bandwidth BR is selected and assigned to the room.

[0013] In this case, the following control methods are possible. First, in transmission control, for example, -Set maximum bit rate and priority (high, normal) for each location - Assign the maximum bit rate of a high priority site to that site ·Allocate remaining bandwidth to normal priority sites In addition, in reception control, for example, - Set whether each site receives media information from the other site - If no other stations are receiving data, the station will stop transmitting. · Allocate the available bandwidth (bandwidth) generated by the suspension of transmission and reception to each base's transmission The following control methods are possible.

[0014] <Dynamic change of room reservation bandwidth> For use cases where it is difficult to predict the number of participating locations in advance, a means for dynamically changing the room reservation bandwidth is provided. The room reservation bandwidth changing means may, for example, -Direct setting of room reservation bandwidth by providing API etc. -Setting the mode to automatically adjust the room reservation bandwidth according to the number of participating sites In the automatic adjustment mode, the room reserved bandwidth can be determined, for example, by the following (Equation 2) for the number of locations N, the sending bit rate send(p, i) of location i with priority p, and a constant B.

[0015]

number

[0016] The method of determining the reserved bandwidth described above is a mode in which bandwidth is secured for media transmission and reception at high priority locations, while the total transmission and reception bandwidth for normal priority locations is determined by a constant B, and the bandwidth becomes narrower as the number of locations increases.

[0017] [Room concept] Figure 2 shows an example of the concept of a room. A "room" is a collection of one or more locations that distribute media information to each other. The media distribution system 5 shown in Figure 2 includes a distribution control device 7 (described later) and one or more media distribution servers 9(1) and 9(2), and provides media distribution functions to an application server 3 (described later).

[0018] Furthermore, the media distribution server 9 includes one or more rooms, and the media distribution server 9(1) includes, for example, room 1 and room 2. Furthermore, the media distribution server 9(2) includes, for example, room 3. Furthermore, the locations 1, 2, and 3 are connected to room 1, and predetermined media information is shared among the respective locations. Furthermore, the locations 4 and 5 are connected to room 2, and predetermined media information is shared among the respective locations. Furthermore, the locations 6 and 7 are connected to room 3, and predetermined media information is shared among the respective locations. Each of these rooms distributes media information between the respective locations using a reserved bandwidth that falls within the maximum bandwidth of the media distribution server that distributes media information to the respective rooms.

[0019] [Overall configuration of communication system] <System configuration example> FIG. 3 is a diagram illustrating an example of the overall configuration of a communication system. As illustrated in FIG. 3, the communication system 1 includes one or more locations A, B, and C, an application server 3, and a media distribution system 5. The locations A, B, and C, the application server 3, and the media distribution system 5 are connected to each other via a communication network 100. The location A includes a camera 2 as an example of a communication device and a display device 4 that displays and plays back images (video) captured by the camera 2 and collected audio. The location B includes a camera 6 and an information processing device 8 that displays and plays back images (video) captured by the camera 6 and collected audio. The information processing device 8 functions as an example of a communication device. The location C includes a camera 6 and a communication terminal 10 that displays and plays back images (video) captured by the camera 6 and collected audio. Here, a location refers to a place where each application provided by the application server 3 is used. Each of these locations provides an environment in which users can use a browser and various apps. The communication terminal 10 functions as an example of a communication device.

[0020] The media distribution system 5 includes a distribution control device 7 that controls information between each base station and establishes communication for the communication of media information, and one or more media distribution servers 9 that receive media information from each base station and distribute it to each base station.

[0021] The communication network 100 is a communication network through which an unspecified number of communications are conducted, and is constructed using the Internet, an intranet, a LAN (Local Area Network), etc. The communication network 100 may include not only wired communication but also communication networks using wireless communication such as 3G (3rd Generation), 4G (4th Generation), 5G (5th Generation), WiMAX (Worldwide Interoperability for Microwave Access), and LTE (Long Term Evolution).

[0022] <Photographing equipment> The image capturing device 2 is a special digital camera for capturing images of subjects such as users using a base, scenery, etc., to obtain two hemispherical images that serve as the basis for a celestial sphere panoramic image. The image capturing device 2 is capable of communicating with the application server 3 and the media distribution server 9 via the communication network 100. As described above, the image capturing device 2 transmits the captured images (video) and collected audio to the display device 4 for display and playback.

[0023] <Display device> The display device 4 is, for example, a device that displays and plays back images (video) and audio transmitted from the image capturing device 2, and is a general display terminal.

[0024] <Photographing equipment> The image capturing device 6 is, for example, a general digital camera for capturing images of subjects such as users using the base, scenery, etc., to obtain general two-dimensional images. As described above, the image capturing device 6 transmits the captured images (video) and collected audio to the information processing device 8 for display and playback.

[0025] <Information processing device> The information processing device 8 is realized by a computer system for performing communications, which is equipped with a general OS, etc. The information processing device 8 is capable of communicating with the application server 3 and the media distribution server 9 via the communication network 100.

[0026] The information processing device 8 has installed thereon, for example, a browser application for communicating with the media distribution system 5 and a screen display application for displaying a screen of a conference or the like on the media information transmitted by the media distribution server 9.

[0027] The information processing device 8 may be a communication terminal having a communication function, such as a commonly used PC (Personal Computer), a portable notebook PC, a mobile phone, a smartphone, a tablet terminal, or a wearable terminal (sunglasses type, wristwatch type, etc.). The information processing device 8 may further be a communication device or a communication terminal capable of running software such as browser software.

[0028] <Communication terminal> The communication terminal 10 is realized by one or more information processing devices (computer systems) for communication that are equipped with a general OS, etc. The communication terminal 10 is capable of communicating with the application server 3 and the media distribution server 9 via the communication network 100.

[0029] The communication terminal 10 has installed thereon, for example, a browser application for communicating with the media distribution system 5 and a screen display application for displaying a screen of a conference or the like on the media information transmitted by the media distribution server 9.

[0030] The communication terminal 10 may be a communication terminal having a communication function, such as a commonly used PC (Personal Computer), a portable notebook PC, a mobile phone, a smartphone, a tablet terminal, or a wearable terminal (sunglasses type, wristwatch type, etc.). The communication terminal 10 may further be a communication device or a communication terminal capable of running software such as browser software.

[0031] <Application Server> The application server 3 is realized by an information processing device (computer system) equipped with a general server OS or the like. The application server 3 is a server that realizes an application for distributing media information using the communication system 1. The application server 3 also holds a client secret issued for each application, and when various requests are made, such as a room creation request, an access token acquisition request, a room reserved bandwidth change request, and a standby status inquiry, the application server 3 assigns the client secret to various request information and transmits the information to the distribution control device 7. Here, the access token acquisition request is a request generated based on a room participation request transmitted by a communication device used at each base (disposed at each base). The room reserved bandwidth change request is a request generated based on a room participation request transmitted by a communication device. The standby status inquiry is a request that is transmitted by a communication device and forwarded to the distribution control device 7. In this way, the application server 3 also functions as an intermediary device that mediates between the communication device and the distribution control device 7.

[0032] The application server 3 may be constructed by a single computer, or may be constructed by multiple computers to which each section (function or means) of storage etc. is divided and arbitrarily assigned. All or part of the functions of the application server 3 may be a server computer existing in a cloud environment, or may be a server computer existing in an on-premise environment.

[0033] <Distribution control device> The delivery control device 7 is realized by one or more information processing devices (computer systems) equipped with a general server OS or the like. As described above, the delivery control device 7 controls information between each base station and controls the establishment of communication for the communication of media information. The delivery control device 7 also distributes connection control information to each base station for receiving media information from the other base station, and controls the transmission and reception of media information between the base stations. Furthermore, the delivery control device 7 determines which media delivery server to assign the room to based on the room reservation bandwidth set by the application server 3 and the bandwidth usage status of each media delivery server.

[0034] The delivery control device 7 may be implemented by a single computer, or may be implemented by multiple computers to which each unit (function or means) such as storage is divided and arbitrarily assigned. All or part of the functions of the delivery control device 7 may be implemented by a server computer in a cloud environment or on-premise environment.

[0035] <Media distribution server> The media distribution server 9 is realized by one or more information processing devices (computer systems) equipped with a general server OS. The media distribution server 9 is a server that receives media information from each location and distributes it to each location. The maximum bandwidth available for transmission and reception is determined by the performance of the server, and the media distribution server 9 distributes media information within that range. The media distribution system 5 further comprises multiple media distribution servers 9, which can be scaled out as needed.

[0036] Furthermore, media distribution server 9 may be constructed by a single computer, or may be constructed by multiple computers to which each section (function or means) such as storage is divided and arbitrarily assigned. Furthermore, all or part of the functions of media distribution server 9 may be a server computer existing in a cloud environment, or a server computer existing in an on-premise environment.

[0037] ●About terminology● In this embodiment, media information refers to information transmitted and received between each base station using (via) the media distribution server 9 as a medium. This information includes information related to images (video) and information related to audio (sound). More specifically, media information includes information such as image (video) data, audio data, text data such as chat, and shared files. Note that in this embodiment, images (video) related to image (video) data including people, space, etc. at each base are mainly handled as an example of media information.

[0038] [Hardware configuration] Next, the hardware configuration of the device or terminal constituting the communication system according to the embodiment will be described with reference to Figures 4 to 7. Note that components may be added or deleted from the hardware configuration of the device or terminal shown in Figures 4 to 7 as needed.

[0039] <Hardware configuration of the imaging device> First, the hardware configuration of the image capturing device 2 will be described with reference to Fig. 4. Fig. 4 is a diagram showing an example of the hardware configuration of an image capturing device. In the following, the image capturing device 2 is assumed to be an omnidirectional (omnidirectional) image capturing device using two image capturing elements, but the number of image capturing elements may be any number greater than or equal to two. Furthermore, the image capturing device does not necessarily have to be a device dedicated to omnidirectional image capturing; an ordinary digital camera, smartphone, or the like may be equipped with an add-on omnidirectional image capturing unit to achieve substantially the same functions as the image capturing device 2.

[0040] As shown in FIG. 4, the photographing device 2 is composed of, for example, an imaging unit 201, an image processing unit 204, an imaging control unit 205, a microphone 208, a sound processing unit 209, a CPU (Central Processing Unit) 211, a ROM (Read Only Memory) 212, an SRAM (Static Random Access Memory) 213, a DRAM (Dynamic Random Access Memory) 214, an operation unit 215, a network I / F 216, a communication unit 217, an antenna 217a, and an electronic compass 218.

[0041] Of these, imaging unit 201 includes wide-angle lenses (so-called fisheye lenses) 202a and 202b each having a field angle of 180° or more for forming a hemispherical image, and two imaging elements 203a and 203b provided corresponding to each wide-angle lens. Imaging elements 203a and 203b include an image sensor such as a CMOS sensor or a CCD (Charge Coupled Device) sensor that converts optical images captured by fisheye lenses 202a and 202b into image data in the form of electrical signals and outputs the image data, a timing generation circuit that generates horizontal or vertical synchronization signals and pixel clocks for the image sensors, and a group of registers that set various commands and parameters required for the operation of the imaging elements.

[0042] The imaging elements 203a and 203b of the imaging unit 201 are each connected to the image processing unit 204 via a parallel I / F bus. On the other hand, the imaging elements 203a and 203b of the imaging unit 201 are connected via a serial I / F bus (such as an I2C bus) separately from the imaging control unit 205. The image processing unit 204 and the imaging control unit 205 are connected to a CPU 211 via a bus 210. Furthermore, a ROM 212, an SRAM 213, a DRAM 214, an operation unit 215, a network I / F 216, a communication unit 217, an electronic compass 218, and the like are connected to the bus 210.

[0043] The image processing unit 204 takes in the image data output from the image sensors 203a and 203b via a parallel I / F bus, performs predetermined processing on each image data, and then synthesizes the image data to generate Mercator image data such as that shown in Figure 3(c).

[0044] The imaging control unit 205 generally sets commands and the like in the registers of the imaging elements 203a and 203b using an I2C bus, with the imaging control unit 205 acting as a master device and the imaging elements 203a and 203b acting as slave devices. Necessary commands and the like are received from the CPU 211. The imaging control unit 205 also uses the I2C bus to retrieve status data and the like from the registers of the imaging elements 203a and 203b and send it to the CPU 211.

[0045] Furthermore, the imaging control unit 205 instructs the imaging elements 203a and 203b to output image data when the shutter button of the operation unit 215 is pressed. Depending on the imaging device 2, it may have a preview display function on a display (for example, the display device 4), a function corresponding to video display, etc. In this case, the image data is output from the imaging elements 203a and 203b continuously at a predetermined frame rate (frames / minute).

[0046] As will be described later, the imaging control unit 205 also functions as a synchronization control means that synchronizes the output timing of image data from the imaging elements 203a and 203b in cooperation with the CPU 211. In this embodiment, the imaging device 2 is not provided with a display unit, but may be provided with a display unit.

[0047] The microphone 208 converts sounds such as voice into sound data (signals). The sound processing unit 209 takes in the sound data output from the microphone 208 via the I / F bus and performs predetermined processing on the sound data.

[0048] The CPU 211 controls the overall operation of the imaging device 2 and executes necessary processing. The ROM 212 stores various programs for the CPU 211. The SRAM 213 and DRAM 214 are work memories that store programs executed by the CPU 211, data in the middle of processing, etc. In particular, the DRAM 214 stores image data in the middle of processing by the image processing unit 204 and processed Mercator image data.

[0049] The operation unit 215 is a collective term for various operation buttons, a power switch, a shutter button, a touch panel that combines display and operation functions, etc. By operating the operation buttons, the user can input various shooting modes, shooting conditions, etc.

[0050] The network I / F 216 is a general term for an interface circuit (such as a USB I / F) with external media such as an SD card or a personal computer. The network I / F 216 may be wireless or wired. The Mercator image data stored in the DRAM 214 is recorded on external media via the network I / F 216, or transmitted to an external device via the network I / F 216 as needed.

[0051] The communication unit 217 communicates with an external device such as the video conference terminal 3a by short-range wireless communication technology such as NFC (Near Field Communication), Bluetooth (registered trademark, hereinafter omitted), or Wi-Fi (registered trademark, hereinafter omitted) via an antenna 217a provided in the image capturing device 2. The communication unit 217 can also transmit Mercator image data to an external device.

[0052] The electronic compass 218 calculates the orientation and tilt (roll rotation angle) of the image capture device 2 from the Earth's magnetism and outputs the orientation and tilt information. This orientation and tilt information is an example of related information (metadata) according to Exif, and is used for image processing such as image correction of captured images. The related information also includes data such as the date and time the image was captured and the data size of the image data.

[0053] <Hardware configuration of display device, information processing device, and communication terminal> Next, the hardware configurations of the display device, information processing device, and communication terminal will be described with reference to Fig. 5. Fig. 5 is a diagram showing an example of the hardware configurations of the display device, information processing device, and communication terminal. As shown in Fig. 5, the display device 4 is constructed by, for example, a computer. The display device 4 includes, for example, a CPU 401, a ROM 402, a RAM 403, an EEPROM 404, a display 407, a short-range communication circuit 408, a network I / F 411, an external device connection I / F 416, and a bus line 420.

[0054] Of these, the CPU 401 controls the overall operation of the display device 4. The ROM 402 stores programs used in processing by the CPU 401. The RAM 403 is used as a work area for the CPU 401. The EEPROM 404 reads and writes various data such as applications under the control of the CPU 401. The display 407 is a type of display means such as a liquid crystal display or organic electroluminescence (EL) display that displays images of subjects, characters, various icons, etc. The short-range communication circuit 408 is a communication circuit for performing short-range wireless communication with a communication device or communication terminal equipped with a wireless communication interface such as NFC, Bluetooth, millimeter-wave wireless communication, Wi-Fi, QR Code (registered trademark; hereinafter omitted), visible light, ambient sound, or ultrasonic wave.

[0055] The network I / F 411 is a communication interface for communicating various data (information) with other devices via the communication network 100. The external device connection I / F 416 is an interface for connecting various external devices. In this case, the external device is, for example, a USB (Universal Serial Bus) memory. The bus line 420 is an address bus, a data bus, etc. for electrically connecting each component such as the CPU 401.

[0056] 5, the information processing device 8 is constructed by, for example, a computer. The information processing device 8 includes, for example, a CPU 801, a ROM 802, a RAM 803, an EEPROM 804, an HD 805, an HDD controller 806, a display 807, a short-range communication circuit 808, a CMOS (Complementary Metal Oxide Semiconductor) sensor 809, an image sensor I / F (Interface) 810, a network I / F 811, a keyboard 812, a pointing device 813, a media I / F 815, an external device connection I / F 816, an audio input / output I / F 817, a microphone 818, a speaker 819, and a bus line 820. Of these, the CPU 801, ROM 802, RAM 803, EEPROM 804, display 807, short-range communication circuit 808, network I / F 811, and external device connection I / F 816 are similar to the respective hardware resources of the CPU 401, ROM 402, RAM 403, EEPROM 404, display 407, short-range communication circuit 408, network I / F 411, and external device connection I / F 416 of the display device 4, and therefore their explanation will be omitted.

[0057] The HD 805 stores various data such as programs. The HDD controller 806 controls the reading and writing of various data from and to the HD 805 under the control of the CPU 801. The CMOS sensor 809 is a type of built-in imaging means that captures an image of a subject under the control of the CPU 801 to obtain image data or video data. Note that the imaging means may be an imaging means configured with a CCD (Charge Coupled Device) sensor or the like instead of a CMOS sensor. The imaging element I / F 810 is a circuit that controls the driving of the CMOS sensor 809. The keyboard 812 is a type of input means equipped with multiple keys for inputting characters, numbers, various instructions, etc. The pointing device 813 is a type of input means for selecting and executing various instructions, selecting a processing target, moving a cursor, etc. The media I / F 815 controls the reading and writing (storage) of data from and to a recording medium 814 such as a flash memory. The audio input / output I / F 817 is a circuit that processes the input and output of audio signals between a microphone 818 and a speaker 819 under the control of the CPU 801. The microphone 818 is a built-in circuit that converts sound into an electrical signal, and acquires information using the electrical signal by capturing voice or sound waves emitted from an external speaker, etc. The speaker 819 is a built-in circuit that converts the electrical signal into physical vibrations to produce sounds such as music or voice.

[0058] 5, the communication terminal 10 is constructed by, for example, a computer. The communication terminal 10 includes, for example, a CPU 1001, a ROM 1002, a RAM 1003, an EEPROM 1004, a display 1007, a short-range communication circuit 1008, a CMOS (Complementary Metal Oxide Semiconductor) sensor 1009, an image sensor I / F (Interface) 1010, a network I / F 1011, a pointing device 1013, a media I / F 1015, an external device connection I / F 1016, an audio input / output I / F 1017, a microphone 1018, a speaker 1019, and a bus line 1020. Of these, CPU 1001, ROM 1002, RAM 1003, EEPROM 1004, display 1007, short-range communication circuit 1008, network I / F 1011 and external device connection I / F 1016 are similar to the respective hardware resources of CPU 401, ROM 402, RAM 403, EEPROM 404, display 407, short-range communication circuit 408, network I / F 411 and external device connection I / F 416 of the display device 4, and therefore their explanation will be omitted. Furthermore, the CMOS sensor 1009, the image sensor I / F 1010, the pointing device 1013, the media I / F 1015, the sound input / output I / F 1017, the microphone 1018, and the speaker 1019 are similar to the respective hardware resources of the CMOS sensor 809, the image sensor I / F 810, the pointing device 813, the media I / F 815, the sound input / output I / F 817, the microphone 818, and the speaker 819 of the information processing device 8, and therefore their explanation will be omitted.

[0059] <Hardware configuration of the imaging device> Next, the hardware configuration of the image capturing device will be described with reference to Fig. 6. Fig. 6 is a diagram showing an example of the hardware configuration of an image capturing device. As shown in Fig. 6, the image capturing device 6 is, for example, a camera used for live streaming or an equivalent image capturing device. The image capturing device 6 includes, for example, a CPU 601, a ROM 602, a RAM 603, an EEPROM 604, a short-range communication circuit 608, a CMOS sensor 609, an image capturing element I / F 610, a network I / F 611, an operation panel 612, an operation unit I / F 613, an external device connection I / F 616, an audio input / output I / F 617, a microphone 618, a speaker 619, and a bus line 620.

[0060] Of these, the CPU 601, ROM 602, RAM 603, EEPROM 604, short-range communication circuit 608, network I / F 611, external device connection I / F 416, and bus line 620 are similar to the respective hardware resources of the CPU 401, ROM 402, RAM 403, EEPROM 404, short-range communication circuit 408, network I / F 411, external device connection I / F 416, and bus line 420 of the display device 4 shown in Figure 5, so their explanation will be omitted.

[0061] Furthermore, the CMOS sensor 609, image sensor I / F 610, sound input / output I / F 617, microphone 618, and speaker 619 are similar to the respective hardware resources of the CMOS sensor 809, image sensor I / F 810, sound input / output I / F 817, microphone 818, and speaker 819 of the information processing device 8 shown in Figure 5, and therefore their explanation will be omitted.

[0062] The operation panel 612 is a general term for various operation buttons, a power switch, a shutter button, a touch panel that combines display and operation functions, etc. The user can input various shooting modes, shooting conditions, etc. by operating the operation panel 612. The operation unit I / F 613 is an interface for providing information such as the various shooting modes and shooting conditions input by the user to the photographing device 6.

[0063] <Hardware configuration of application server, distribution control device, and media distribution server> Next, the hardware configurations of the application server, distribution control device, and media distribution server will be described with reference to FIG. 7. FIG. 7 is a diagram showing an example of the hardware configuration of the application server, distribution control device, and media distribution server. As shown in FIG. 7, the application server 3 is implemented by, for example, a computer. The application server 3 includes, for example, a CPU 301, a ROM 302, a RAM 303, an EEPROM 304, an HD 305, an HDD (Hard Disk Drive) controller 306, a short-range communication I / F 308, a network I / F 311, a keyboard 312, a pointing device 313, a media I / F 315, an external device connection I / F 516, and a bus line 320. These hardware resources are similar to the CPU 401, ROM 402, RAM 403, EEPROM 404, short-range communication circuit 408, network I / F 411, external device connection I / F 416, and bus line 420 of the display device 4 shown in FIG. 5, and therefore will not be described here.

[0064] Furthermore, the HD 305, HDD (Hard Disk Drive) controller 306, keyboard 312, pointing device 313, media I / F 315, and external device connection I / F 516 are similar to the HD 805, HDD (Hard Disk Drive) controller 806, keyboard 812, pointing device 813, media I / F 815, and external device connection I / F 816 of the information processing device 8 shown in Figure 5, so their explanation will be omitted.

[0065] 7, the distribution control device 7 is constructed, for example, by a computer. The distribution control device 7 includes, for example, a CPU 701, a ROM 702, a RAM 703, an EEPROM 704, a HD 705, a HDD (Hard Disk Drive) controller 706, a short-range communication I / F 708, a network I / F 711, a keyboard 712, a pointing device 713, a media I / F 715, an external device connection I / F 716, and a bus line 720. These hardware resources are similar to the hardware resources of the application server 3, namely, the CPU 301, the ROM 302, the RAM 303, the EEPROM 304, the HD 305, the HDD (Hard Disk Drive) controller 306, the short-range communication I / F 308, the network I / F 311, the keyboard 312, the pointing device 313, the media I / F 315, the external device connection I / F 516, and the bus line 320, and therefore description thereof will be omitted.

[0066] 7, media distribution server 9 is constructed, for example, by a computer. Media distribution server 9 includes, for example, a CPU 901, a ROM 902, a RAM 903, an EEPROM 904, a HD 905, a HDD (Hard Disk Drive) controller 906, a short-range communication I / F 908, a network I / F 911, a keyboard 912, a pointing device 913, a media I / F 915, an external device connection I / F 916, and a bus line 920. These hardware resources are similar to the hardware resources of application server 3, namely, CPU 301, ROM 302, RAM 303, EEPROM 304, HD 305, HDD (Hard Disk Drive) controller 306, short-range communication I / F 308, network I / F 311, keyboard 312, pointing device 313, media I / F 315, external device connection I / F 516, and bus line 320, and therefore description thereof will be omitted.

[0067] Furthermore, the above-mentioned program may be recorded on a computer-readable recording medium as an installable or executable file, or may be downloaded and distributed via a network. Examples of recording media include CD-Rs (Compact Disc Recordables), DVDs (Digital Versatile Disks), Blu-ray Discs, SD cards, and USB memory. Furthermore, the recording media may be provided domestically or internationally as a program product. For example, the distribution control device 7 realizes the distribution control method according to the present invention by executing the program according to the present invention.

[0068] [Functional configuration of communication system] Next, the functional configuration of this embodiment will be described with reference to Fig. 8 to Fig. 15. Fig. 8 is a diagram showing an example of the functional configuration of a communication system.

[0069] <Functional configuration of distribution control device> As shown in Fig. 8, the distribution control device 7 includes a transmitting / receiving unit 71, an acquiring unit 72, a calculating unit 73, a selecting / allocating unit 74, a determining unit 75, a verifying unit 76, a signature generating unit 77, a status managing unit 78, and a storing / reading unit 79. Each of these functional units is a function or means realized by any of the hardware resources shown in Fig. 7 operating in response to an instruction from a CPU 701 in accordance with a program for the distribution control device 7 loaded from at least one of a ROM 702, an EEPROM 704, and a HD 705 to a RAM 703. The distribution control device 7 also includes a storage unit 7000 constructed from at least one of a ROM 702, an EEPROM 704, and a HD 705 shown in Fig. 7. The storage unit 7000 further stores a communication program (communication application) for communicating with the communication devices, application server 3, and media distribution server 9 used at each location via a communication network 100, a browser application for displaying media information, and the like.

[0070] <<Functional configuration of distribution control device>> Next, each functional component of the distribution control device 7 will be described in detail. The transmission / reception unit 71 of the distribution control device 7 shown in FIG. 8 is mainly realized by the processing of the CPU 701 on the network I / F 711 and the short-range communication I / F 708, and transmits and receives various data (or information) between the communication device, the application server 3, and the media distribution server 9 via the communication network 100. The transmission / reception unit 71 also transmits a connection response as a response to the connection request to the communication device of the predetermined base. In this case, the communication device of the predetermined base is a communication device used at a predetermined base included in the predetermined assembly base that has transmitted information related to a connection request for connecting to a distributable media distribution server allocated by the selection / allocation unit 74 described below. The connection response also includes destination information (address information) addressed to the distributable media distribution server. The transmission / reception unit 71 also transmits information related to a reconnection request for reconnecting to another newly allocated media distribution server to the communication device of each base included in the predetermined assembly base. The transmission / reception unit 71 also transmits the generated access token so that the communication device of each base included in the predetermined assembly base receives the access token. The transmitting / receiving unit 71 also transmits to the communication device at each base a connection response to a connection request, which includes an access token for requesting a connection to a media distribution server capable of distributing the media, sent by the communication device at each base. In this embodiment, the transmitting / receiving unit 71 functions as an example of at least one of a transmitting means and a receiving means.

[0071] The acquisition unit 72 is mainly realized by processing of the CPU 701, and acquires an access token including room identification information and location identification information, which will be described later, from each location. In this embodiment, the acquisition unit 72 functions as an example of an acquisition means.

[0072] The calculation unit 73 is mainly realized by processing of the CPU 701, and calculates the available bandwidth of the media distribution server 9. Specifically, the calculation unit 73 calculates the difference between the reserved bandwidth for distribution required by a given media distribution server and the maximum reserved bandwidth available to the given media distribution server. In this embodiment, the calculation unit 73 functions as an example of a calculation means.

[0073] The selection and allocation unit 74 is realized by processing of the CPU 701 and calculates the available bandwidth in the media distribution server 9. The selection and allocation unit 74 assigns a media distribution server selected based on the reserved bandwidth for distribution required by the specified media distribution server and the maximum reserved bandwidth available for the specified media distribution server as a media distribution server capable of distribution to communication devices at each base in a specified collection point including one or more bases sharing the specified media information. Furthermore, if the reserved bandwidth exceeds the maximum reserved bandwidth, the selection and allocation unit 74 assigns another media distribution server capable of accommodating the reserved bandwidth in place of the specified media distribution server as a media distribution server capable of distribution to the communication devices at each base. Furthermore, if the reserved bandwidth exceeds the maximum reserved bandwidth, the selection and allocation unit 74 assigns an additional media distribution server in place of the specified media distribution server as a new media distribution server capable of delivering the specified media information to the communication devices at each base. Furthermore, when the reserved bandwidth exceeds the maximum reserved bandwidth, the selective allocation unit 74 moves a specific collection point managed by a predetermined media distribution server from the predetermined media distribution server to another media distribution server, and then assigns the predetermined media distribution server as a media distribution server capable of delivering to the communication devices of each location. Furthermore, the selective allocation unit 74 assigns the reserved bandwidth to another media distribution server that can accommodate it based on the difference calculated by the calculation unit 73. Furthermore, when the determination unit 75 (described later) determines that the reserved bandwidth can be accommodated within the reserved bandwidth, the selective allocation unit 74 assigns the media distribution server to the predetermined media distribution server, and when the determination unit 75 determines that the reserved bandwidth cannot be accommodated within the reserved bandwidth, the selective allocation unit 74 assigns the media distribution server to another media distribution server instead. In this embodiment, the selective allocation unit 74 functions as an example of allocation means.

[0074] The determination unit 75 is mainly realized by the processing of the CPU 701, and makes various determinations in the distribution control device 7. Specifically, the determination unit 75 determines whether the reserved bandwidth for distribution required by a predetermined media distribution server calculated by the calculation unit 73 can be accommodated within the maximum reserved bandwidth available to the predetermined media distribution server (whether it is equal to or less than the maximum reserved bandwidth). In this embodiment, the determination unit 75 functions as an example of a determination means.

[0075] The verification unit 76 is mainly realized by processing of the CPU 701, and verifies the client by referring to a client management DB (described later) based on the room creation request, access token acquisition request, connection request, and room participation request sent by the application server 3. In this embodiment, the verification unit 76 functions as an example of a verification means.

[0076] The signature generating unit 77 is mainly realized by the processing of the CPU 701, and when the verification unit 76 has verified the client, the signature generating unit 77 generates an access token including room identification information and location identification information (described later) and signs the access token using a client secret related to the client. Furthermore, the signature generating unit 77 generates an access token including gathering location identification information that identifies the predetermined gathering location and location identification information, either the predetermined location identification information that identifies the predetermined location or the other location identification information that identifies the other location, based on at least one of a predetermined join request for a predetermined gathering location transmitted by a communication device at the predetermined location and another join request for a predetermined gathering location transmitted by a communication device at another location. In this embodiment, the signature generating unit functions as an example of a generating means. Furthermore, the signature generating unit functions as an example of a signing means.

[0077] In the communication system according to the present embodiment, signature generating unit 77 may be provided in distribution control device 7, or may be provided in another device that can communicate with distribution control device 7 and communication devices at each base via communication network 100. Furthermore, signature generating unit 77 may be provided in media distribution server 9.

[0078] The state management unit 78 is mainly realized by the processing of the CPU 701, and changes the state of the media distribution server by referring to a media distribution server management DB (described later) based on a media distribution server setup completion notification received by the transmitting / receiving unit 71 from the media distribution server 9. In this embodiment, the state management unit 78 functions as an example of state management means.

[0079] The memory / read unit 79 is mainly realized by processing of the CPU 701 on at least one of the ROM 702, the EEPROM 704, and the HD 705, and stores various data (or information) in the memory unit 7000 and reads various data (or information) from the memory unit 7000. In this embodiment, the memory / read unit 79 functions as an example of a memory / read means.

[0080] ●Client Management Table● Fig. 9 is a conceptual diagram showing an example of a client management table. A client management DB 7001 configured by a client management table such as that shown in Fig. 9 is constructed in the storage unit 7000. In the client management table, the items of a client key and a client secret are associated with each other for each piece of client identification information that identifies a client, and are stored and managed.

[0081] Of these, the client key is information specific to the application for the application server 3, and is given as information such as "AAAAAAAA" or "CCCCCCCC." The client secret is other information specific to the application that is managed in pairs with the client key, and is given as information such as "BBBBBBBB" or "DDDDDDDD."

[0082] ●Media distribution server management table● Fig. 10 is a conceptual diagram showing an example of a media distribution server management table. A media distribution server management DB 7002 configured by the media distribution server management table shown in Fig. 10 is constructed in the storage unit 7000. In the media distribution server management table, the maximum reserved bandwidth, address information, and status items are associated with each media distribution server identification information that identifies the media distribution server 9, and are stored and managed.

[0083] Of these, the maximum reserved bandwidth represents the maximum bandwidth for transmitting and receiving media information that is predetermined based on the performance of the media distribution server 9, and is given a bandwidth of, for example, 100 Mbps. The address information is address information given to the media distribution server 9, and is given, for example, as "sfu1@example.com." The status represents the status of the media distribution server 9, and is managed as, for example, "setting up," "setup completed," etc.

[0084] ●Room Management Table● Fig. 11 is a conceptual diagram showing an example of a room management table. A room management DB 7003 configured by a room management table such as that shown in Fig. 11 is constructed in the storage unit 7000. In the room management table, room identification information, reserved bandwidth, media distribution server identification information, and base identification information are stored and managed in association with each piece of client identification information.

[0085] Of these, the room identification information is information for identifying a gathering point, which is a gathering of one or more points, and is given, for example, "R0002," "R0003," etc. In this embodiment, the gathering point is called a "room." The reserved bandwidth represents the bandwidth used when a client reserves a room, and is given, for example, a bandwidth of 90 [Mbps], 50 [Mbps], etc. In this embodiment, the reserved bandwidth value or the total reserved bandwidth value is controlled so as not to exceed the maximum reserved bandwidth of the corresponding media distribution server. The media distribution server identification information is information for identifying the media distribution server 9, and is given, for example, "M0091," "M0092," etc. The point identification information is information for identifying each point included in the room, and is given, for example, "MB000A," "B000B," etc.

[0086] ●Access Token Management Table● FIG. 12 is a conceptual diagram showing an example of an access token management table. An access token management DB 7004 configured by the access token management table shown in FIG. 12 is created in the storage unit 7000. In the access token management table, key names constituting an access token are associated with their values, and stored and managed. Among these, the key names include the above-mentioned room identification information, base identification information, etc. Furthermore, a value corresponding to the room identification information, such as "R0001", is assigned to the value. Furthermore, a value corresponding to the base identification information, such as "B000A", is assigned to the value.

[0087] <Functional configuration of media distribution server> Returning to Fig. 8, media distribution server 9 has a transmitting / receiving unit 91, a generating unit 96, an executing unit 97, and a storing / reading unit 99. Each of these functional units is a function or means realized when any of the hardware resources shown in Fig. 7 operates in response to instructions from CPU 901 in accordance with a program for media distribution server 9 that is loaded from at least one of ROM 902, EEPROM 904, and HD 905 to RAM 903. Media distribution server 9 also has a memory unit 9000 constructed from at least one of ROM 902, EEPROM 904, and HD 905 shown in Fig. 7. Furthermore, memory unit 9000 stores a communication program (communication application) for communicating with communication devices, application server 3, and distribution control device 7 used at each location via communication network 100, a browser application for displaying media information, and the like. In this embodiment, one or more media distribution servers 9 are included in the media distribution system 5, but unless otherwise specified, the numbers assigned to each functional unit will be referred to as the transmission / reception unit 91, generation unit 96, execution unit 97, and storage / reading unit 99, as described above.

[0088] <<Functional configuration of the media distribution server>> Next, a detailed description will be given of each functional configuration of the media distribution server 9. The transmission / reception unit 91 of the media distribution server 9 shown in Fig. 8 is mainly realized by processing of the CPU 901 on the network I / F 911 and the short-range communication I / F 908, and transmits and receives various data (or information) between the communication device, the application server 3, and the distribution control device 7 via the communication network 100. In this embodiment, the transmission / reception unit 91 functions as an example of at least one of a transmitting means and a receiving means.

[0089] The generation unit 96 is mainly realized by the processing of the CPU 901, and generates credential information by encrypting the room identification information and base identification information received from the distribution control device 7. At this time, the generation unit 96 generates the credential information using a shared key held at the time of its own setup. The credential information generated by the generation unit 96 is based on credential information transmitted by the communication device of each base (described later), and the received credential information is decrypted using the shared key to extract the room identification information and base identification information, thereby verifying the legitimacy of the base and identifying which bases are to be managed in the same room. In this embodiment, the generation unit 96 functions as an example of a generation means.

[0090] The execution unit 97 is mainly realized by the processing of the CPU 901, and executes setup of the media distribution server 9 itself based on a startup request sent by the distribution control device 7. In this embodiment, the execution unit 97 functions as an example of an execution means.

[0091] The memory / read unit 99 is mainly realized by the processing of the CPU 901 on at least one of the ROM 902, the EEPROM 904, and the HD 905, and stores various data (or information) in the memory unit 9000 and reads various data (or information) from the memory unit 9000. In this embodiment, the memory / read unit 99 functions as an example of a memory / read means.

[0092] <Application server functional configuration> FIG. 13 is a diagram showing an example of the functional configuration of a communication system. As shown in FIG. 13, application server 3 includes a transmitting / receiving unit 31, a determining unit 35, a requesting unit 36, and a storing / reading unit 39. These functional units are functions or means realized by operating any of the hardware resources shown in FIG. 7 in response to instructions from CPU 301 in accordance with a program for application server 3 loaded from at least one of ROM 302, EEPROM 304, and HD 305 to RAM 303. Application server 3 also includes a storage unit 3000 constructed using at least one of ROM 302, EEPROM 304, and HD 305 shown in FIG. Furthermore, storage unit 3000 stores a communication program (communication application) for communicating with communication devices, distribution control device 7, and media distribution server 9 used at each location via communication network 100, a media information distribution application, and the like.

[0093] <<Application Server Functional Configuration>> Next, each functional configuration of the application server 3 will be described in detail. The transmission / reception unit 31 of the application server 3 shown in Fig. 13 is mainly realized by processing of the CPU 301 on the network I / F 311 and the short-range communication I / F 308, and transmits and receives various data (or information) between the communication device, the delivery control device 7, and the media delivery server 9 via the communication network 100. The transmission / reception unit 31 also transmits information related to various requests, such as a room creation request, an access token acquisition request, a room reservation bandwidth change request, and a standby state inquiry, to the delivery control device 7. The transmission / reception unit 31 also receives various responses from the delivery control device 7 to the various requests described above. In this embodiment, the transmission / reception unit 31 functions as an example of at least one of a transmitting means and a receiving means.

[0094] The determination unit 35 is mainly realized by the processing of the CPU 301, and determines whether or not the reserved bandwidth of the media distribution server 9 needs to be changed in response to a room join request sent from each location. The determination unit 35 may also be configured to determine whether or not the reserved bandwidth of the media distribution server 9 needs to be changed. In this embodiment, the determination unit 35 functions as an example of a determination means.

[0095] The request unit 36 ​​is mainly realized by the processing of the CPU 301, and makes various requests to the distribution control device 7, such as the above-mentioned room creation request, access token acquisition request, room reserved bandwidth change request, standby state inquiry, etc. In this embodiment, the request unit 36 ​​functions as an example of request means.

[0096] The memory readout unit 39 is mainly realized by the processing of the CPU 301 on at least one of the ROM 302, the EEPROM 304, and the HD 305, and stores various data (or information) in the memory unit 3000 and reads various data (or information) from the memory unit 3000. In this embodiment, the memory readout unit 39 functions as an example of a memory readout means.

[0097] ●Client Management Table● Fig. 14 is a conceptual diagram showing an example of a client management table. A client management DB 3001 configured by a client management table such as that shown in Fig. 14 is created in the storage unit 3000. This client management DB 3001 has a similar configuration to the above-mentioned client management DB 7001, and therefore a detailed description thereof will be omitted.

[0098] <Functional configuration of communication device> FIG. 15 is a diagram illustrating an example of the functional configuration of a communication system. As shown in FIG. 15, a communication device A disposed at (used at) a site A includes a transceiver unit A1, an image capture unit A2, a sound processing unit A3, a display control unit A4, a processing startup unit A8, and a storage / readout unit A9. These functional units are functions or means realized by operating any of the hardware resources shown in FIG. 4 in response to instructions from a CPU 211 in accordance with a communication device program loaded from at least one of a ROM 212 and an SRAM 213 to a DRAM 214. The communication device also includes a storage unit A10 constructed using at least one of the ROM 212 and the SRAM 213 shown in FIG. 4. The storage unit A10 further stores a communication program (communication application) for communicating with the application server 3, the distribution control device 7, and the media distribution server 9 via a communication network 100. In addition, communication device B (used at location B) located at location B and communication device C (used at location C) located at location C are realized using the same hardware resources as communication device A, so detailed explanations will be omitted.

[0099] <<Functional configuration of communication device>> Next, each functional component of communication device A will be described in detail. Similarly, each functional component of communication device B and communication device C is the same as the functional component of communication device A, so detailed description will be omitted. The transmission / reception unit A1 of communication device A shown in Fig. 15 is mainly realized by processing of CPU 301 on network I / F 311 and short-range communication I / F 308, and transmits and receives various data (or information) between the communication device, distribution control device 7, and media distribution server 9 via communication network 100. In this embodiment, the transmission / reception unit A1 functions as an example of at least one of a transmitting means and a receiving means.

[0100] The imaging acquisition unit A2 is mainly realized by the processing of the CPU 211 on the imaging elements 203a, 203b and the imaging control unit 205, and acquires images (video) by capturing images of the faces, etc. of users at each location (location A) as subjects. In this embodiment, the imaging acquisition unit A2 functions as an example of an imaging acquisition means.

[0101] The sound processing unit A3 is mainly realized by processing by the CPU 211 on the microphone 208 and the sound processing unit 209, and performs processing to collect speech sounds spoken at each location (location A) and sounds generated at each location (location A) and generate sound signals. In this embodiment, the sound processing unit A3 functions as an example of a sound processing means.

[0102] The display control unit A4 is mainly realized by the processing of the CPU 211 on the display device 4, and controls the display of various screens and information (data) on the communication device A. The display control unit A4 also uses, for example, a browser to display a display screen created using HTML or the like on the display device 4. The display control unit A4 also displays predetermined media information transmitted by a media distribution server that can distribute the media on the display device 4, etc. In this embodiment, the display control unit A4 functions as an example of a display control means.

[0103] The process startup unit A8 is mainly realized by the processing of the CPU 211, and starts up the media information distribution app installed in the communication device A to execute the media information distribution service. The process startup unit A8 also runs the media information distribution app and browser app managed by the communication device A in a predetermined working area of ​​the DRAM 214. In response to a media distribution server reconnection request sent by the distribution control device 7, the process startup unit A8 also disconnects the currently connected media distribution server and performs processing to connect to a new media distribution server. In this embodiment, the process startup unit A8 functions as an example of a startup processing means.

[0104] The storage and reading unit A9 is mainly realized by the processing of the CPU 211 on at least one of the ROM 212 and the SRAM 213, and stores various data (or information) in the storage unit A10 and reads various data (or information) from the storage unit A10. In this embodiment, the storage and reading unit A9 functions as an example of a storage and reading means.

[0105] [Processing or Operation of the Embodiment] <Room Creation> Next, each process or operation in the communication system according to the first embodiment will be described with reference to Fig. 16 to Fig. 22. Fig. 16 is a sequence diagram showing an example of a room creation process. First, the storage and reading unit 39 of the application server 3 reads out each piece of information on the client key and client secret corresponding to each piece of client identification information by reading out the client management DB 3001 (see Fig. 14) (step S101). In this case, the storage and reading unit 39 may read out all of the client keys and client secrets.

[0106] Next, the request unit 36 ​​of the application server 3 specifies the room reservation bandwidth and transmits information related to the room creation request to the delivery control device 7 (step S102). As a result, the transmitting / receiving unit 71 of the delivery control device 7 receives the information related to the room creation request transmitted by the application server 3. At this time, the room creation request includes the client identification information, the client key ("AAAAAAA" ), client secret ("BBBBBBB"), room identification information indicating room 1 ("R0001"), and reserved bandwidth ("10[Mbps]").

[0107] Next, the storage / reading unit 79 of the distribution control device 7 searches the client management DB 7001 (see FIG. 9) using the client identification information received in step S102 as a search key, and reads out the corresponding client key and client secret. Then, the verification unit 76 compares the pair of client key and client secret further received in step S102 with the read pair of client key and client secret to perform verification (step S103). In this embodiment, it is assumed that the information related to the client 1 that sent the information related to the room creation request has passed verification.

[0108] Next, the storage / reading unit 79 searches the room management DB 7003 (see FIG. 11) using the received client identification information as a search key to read out the corresponding media distribution server identification information and reserved bandwidth. Thereafter, the calculation unit 73 searches the media distribution server management DB 7002 (see FIG. 10) using the media distribution server identification information as a search key to read out the corresponding maximum reserved bandwidth and calculate the difference from the reserved bandwidth (step S104).

[0109] Next, the selection and allocation unit 74 selects and allocates a media distribution server based on the available bandwidth calculated in step S104 (step S105). Here, the media distribution server selection algorithm may be, for example, the following method. A. Allocate the server with the most available capacity B. Assign the reserved bandwidth to the server with the least available capacity. C. Rotate in round robin and assign the first available server Therefore, in this embodiment, it is assumed that media distribution server 1 is selected by B or C. Specifically, the selection allocation unit 74 allocates room 1 to media distribution server 1 in the room management DB 7003 (see FIG. 11). In this case, room 1 includes base A and base B, so base A and base B are added to the base column. This addition process is possible because room 2, with a reserved bandwidth of 90 [Mbps], has already been allocated to media distribution server 9(1), which has media distribution server identification information "M0091." In this state, the reserved bandwidth for room 1 is set to 10 [Mbps], which can be accommodated within the maximum reserved bandwidth of 100 [Mbps] for media distribution server 9(1). Furthermore, as described above in B, media distribution server 9(1) is allocated in accordance with the principle of allocating the server with the least available capacity.

[0110] By the processing of step S105, the following contents are added to the room management DB 7003 (see FIG. 11). In this case, "C0001" is added to the client identification information, and "R0001" is added to the corresponding room identification information, "10" is added to the reserved bandwidth, and "M0091" is added to the media distribution server identification information. Note that no additions or changes are made to the base identification information items.

[0111] Next, the transmitting / receiving unit 71 transmits a room creation response to the application server 3 as a response to the room creation request of step S102 (step S106). As a result, the transmitting / receiving unit 31 of the application server 3 receives the room creation response transmitted by the distribution control device 7. At this time, the room creation response includes notification content indicating the success of the room creation and information about the assigned media distribution server 1 (for example, the media distribution server name).

[0112] In the communication system according to this embodiment, for example, when the processes of steps S102 and S106 described above are executed, other devices may exist between the application server 3 and the delivery control device 7. In other words, each piece of information (data) exchanged between the application server 3 and the delivery control device 7 may be exchanged once via another device. The above-described configuration is applicable even if other processing steps exist between the application server 3 and the delivery control device 7.

[0113] <Connection from each site (Connection from site A)> Next, the connection processing from each base will be described. Fig. 17A is a sequence diagram showing an example of the connection processing from base A. First, the transmitting / receiving unit A1 of communication device A used at base A transmits information related to a room participation request to the application server 3 in order to participate in a predetermined room on the application server 3 (step S111). As a result, the transmitting / receiving unit 31 of the application server 3 receives the information related to the room participation request transmitted by communication device A. At this time, the information related to the room participation request includes, for example, information indicating the room location and information related to a request to acquire an access token for accessing the distribution control device 7.

[0114] Next, the determination unit 35 of the application server 3 determines whether to change the reserved bandwidth (step S112). Specifically, the determination unit 35 determines that even if site A included in room 1 joins, there is still room in the reserved bandwidth set for room 1.

[0115] Next, the transmitting / receiving unit 31 transmits information related to the access token acquisition request to the delivery control device 7 (step S113). As a result, the transmitting / receiving unit 71 of the delivery control device 7 receives the information related to the access token acquisition request transmitted by the application server 3. At this time, the access token acquisition request includes the client key, client secret, and room identification information ("R0001 ") and base identification information ("B000A").

[0116] Next, the verification unit 76 of the distribution control device 7 verifies the client (step S114). The process in this step is the same as step S103 described above, and therefore a detailed description thereof will be omitted.

[0117] Subsequently, the signature generating unit 77 generates and signs an access token (step S115). Specifically, the signature generating unit 77 generates and signs the room identification information ("R0001 The access token management DB 7004 (see FIG. 12) registers the room identification information ("R0001") and the location identification information ("B000A") in the corresponding value field, and signs the access token using the client secret. In other words, the access token generated at this time includes the room identification information ("R0001"), the location identification information ("B000A"), and the client secret.

[0118] Next, the transmitting / receiving unit 71 transmits an access token acquisition response to the application server 3 as a response to the access token acquisition request of step S113 (step S116). As a result, the transmitting / receiving unit 31 of the application server 3 receives the access token acquisition response transmitted by the delivery control device 7. At this time, the access token acquisition response includes the room identification information ("R0001") and the base identification information ("B000A").

[0119] Next, the transmitting / receiving unit 31 of the application server 3 transmits a room participation response to the communication device A at the site A as a response to the room participation request of step S111 (step S117). As a result, the transmitting / receiving unit A1 of the communication device A at the site A receives the room participation response transmitted by the application server 3. At this time, the room participation response includes notification content indicating successful room participation and an access token.

[0120] In the communication system according to this embodiment, for example, when the processes of steps S111 and S117 described above are executed, other devices may exist between the communication device and the application server 3. In other words, each piece of information (data) transmitted and received between the communication device and the application server 3 may be transmitted and received once via another device. The above-described configuration is applicable even if other processing steps exist between the communication device and the application server 3.

[0121] Next, the rest of the connection processing from site A will be explained. FIG. 17B is a sequence diagram showing an example of the connection processing from site A. The transmitting / receiving unit A1 of communication device A at site A transmits information related to a connection request for connecting a media distribution server to the distribution control device 7 (step S121). As a result, the transmitting / receiving unit 71 of the distribution control device 7 receives the information related to the connection request transmitted by communication device A. Specifically, the transmitting / receiving unit A1 of communication device A adds the client identification information and the acquired access token to the connection request and transmits it to the distribution control device 7.

[0122] Next, the verification unit 76 of the distribution control device 7 verifies the access token (step S122). Specifically, the verification unit 76 searches the client management DB 7001 (see FIG. 9) using the client identification information included in the received access token as a search key, reads out the corresponding client secret, and verifies whether it matches the client secret used when signing the access token.

[0123] Next, signature generating unit 77 generates address information for transmitting the media information (step S123). Specifically, signature generating unit 77, in cooperation with storage / reading unit 79, reads out room identification information ("R0001") and location identification information ("B000A") from access token management DB 7004 (see FIG. 12). Next, signature generating unit 77 references corresponding media distribution server identification information by searching room management DB 7003 (see FIG. 11) using the room identification information ("R0001") as a search key. Furthermore, signature generating unit 77 generates address information corresponding to the referenced media distribution server identification information as address information for communication device A at location A to transmit the media information, and registers the generated address information in the corresponding address information item in media distribution server management DB 7002 (see FIG. 10).

[0124] Next, the storage / readout unit 79 adds the location identification information of Room 1 ("B000A") to the location identification information in the room management DB 7003 (see FIG. 11) (step S124).

[0125] By the process of step S124, in addition to the content added by the process of step S105, "B000A" representing the identification information of site A is added to the site identification information item in the room management DB 7003 (see FIG. 11).

[0126] Next, the transmitting / receiving unit 71 of the distribution control device 7 transmits a connection request to the media distribution server 9 (step S125). As a result, the transmitting / receiving unit 91 of the media distribution server 9 receives the connection request transmitted by the distribution control device 7. At this time, the connection request includes the room identification information (R0001) and base identification information (B000A) received in step S113.

[0127] Next, the generation unit 96 of the media distribution server 9 encrypts the received room identification information (R0001) and location identification information (B000A) to generate credential information (step S126). At this time, the media distribution server 9 uses the shared key that it held when it was set up.

[0128] Next, the transmitting / receiving unit 91 transmits the generated credential information to the distribution control device 7 (step S127). As a result, the transmitting / receiving unit 71 of the distribution control device 7 receives the credential information transmitted by the media distribution server 9.

[0129] Next, the transmitting / receiving unit 71 of the delivery control device 7 transmits a connection response to the connection request to communication device A at location A (step S128). Specifically, the transmitting / receiving unit 71 transmits a connection request to a media delivery server 9 that can deliver, as a connection response to communication device A at location A. As a result, the transmitting / receiving unit A1 of communication device A receives the connection response to the connection request transmitted by the delivery control device 7. At this time, the connection request to media delivery server 9(1) as a connection response includes the credential information received in step S127 and address information (e.g., "sfu1@example.com") for receiving media information from location A.

[0130] Next, the transmitting / receiving unit A1 of communication device A starts transmitting media information to the connected media distribution server 9(1) (step S129). As a result, the transmitting / receiving unit 91 of media distribution server 9(1) receives information accompanying the start of transmission of the media information transmitted by communication device A. At this time, the information accompanying the start of transmission of the media information includes, for example, credential information, transmission address information of media distribution server 9(1) ("sfu1@example.com"), and media information of location A.

[0131] In the communication system according to this embodiment, for example, when the processes of steps S121 and S125 described above are executed, other devices may exist between the communication device and the distribution control device 7. In other words, each piece of information (data) transmitted and received between the communication device and the distribution control device 7 may be transmitted and received once via another device. The above-described configuration is applicable even if other processing steps exist between the communication device and the distribution control device 7.

[0132] <Connection from each base (Connection from base B)> Next, a description will be given of the connection processing from base B. Fig. 18A is a sequence diagram showing an example of the connection processing from base B. Note that the processing from the following steps S131 to S137 is the same as the processing from steps S111 to S117 described above, except that the communication device making the room join request is changed to communication device B and the base identification information is changed from "B000A" to "B000B", and therefore a description thereof will be omitted.

[0133] Next, the continuation of the connection processing from location B will be described. Fig. 18B is a sequence diagram showing an example of the connection processing from location B. Note that the processing from steps S141 to S148 shown in Fig. 18B is the same as the processing from steps S121 to S128 described above, except that the location identification information for the location to be added is changed from "B000A" to "B000B", and therefore description thereof will be omitted. However, in step S145, the connection response sent by the distribution control device 7 includes address information for sending media information from communication device B at location B and address information for communication device B at location B to receive media information from location A.

[0134] In addition, by the processing of step S144, in addition to the content added by the processing of step S124, "B000B" representing the identification information of site B is further added to the site identification information item in the room management DB 7003 (see FIG. 11).

[0135] Next, the transmitting / receiving unit B1 of communication device B starts transmitting media information to the media distribution server 9(1) and starts receiving the media information of location A from the receiving address information of location A (step S149). As a result, the transmitting / receiving unit 91 of the media distribution server 9(1) receives the media information transmitted by communication device B.

[0136] Next, the transmitting / receiving unit 91 transmits the media information of the location A to the communication device B of the location B (step S150). As a result, the transmitting / receiving unit B1 of the communication device B receives the media information of the location A transmitted by the media distribution server 9(1).

[0137] Next, the display control unit B4 of the communication device B displays the media information of the location A received in the process of step S147 on the display 807 of the communication device B (information processing device 8) (step S151).

[0138] In the communication system according to this embodiment, for example, when the processes of steps S146 and S147 described above are executed, other devices may exist between the communication device and the media distribution server 9. In other words, each piece of information (data) transmitted and received between the communication device and the media distribution server 9 may be transmitted and received once via another device. The above-described configuration is applicable even if other processing steps exist between the communication device and the media distribution server 9.

[0139] Next, the connection process from location B will be described. FIG. 18C is a sequence diagram showing an example of the connection process from location B. The transmitter / receiver A1 of communication device A transmits information related to a connection request from media distribution server 9(1) to the distribution control device 7 (step S156). As a result, the transmitter / receiver 71 of the distribution control device 7 receives information related to the connection request for media 9(1) transmitted by communication device A. At this time, the connection request for media 9(1) includes receiving address information for receiving the media information transmitted by communication device B at location B.

[0140] Next, the transmitting / receiving unit A1 of communication device A starts receiving the media information of location B (step S157). As a result, the transmitting / receiving unit 91 of media distribution server 9(1) receives the information to start receiving the media information of location B transmitted by communication device A. At this time, the information to start receiving the media information of location B includes address information (for example, "sfu1@example.com") for receiving the media information transmitted by communication device B.

[0141] Next, the transmitting / receiving unit 91 of the media distribution server 9(1) transmits the media information of the location B to the communication device A (step S158). As a result, the transmitting / receiving unit A1 of the communication device A receives the media information of the location B transmitted by the media distribution server 9(1).

[0142] Next, the display control unit A4 of the communication device A displays the media information of the location B on the display 407 of the display device 4 (step S159).

[0143] <Connection from each base (Connection from base C)> Next, the connection process from the base C will be described. FIG. 19A is a sequence diagram showing an example of the connection process from the base C. First, the transmitting / receiving unit C1 of the communication device C used at the base C transmits information related to a room participation request to the application server 3 in order to participate in a predetermined room on the application server 3 (step S161). As a result, the transmitting / receiving unit 31 of the application server 3 receives the information related to the room participation request transmitted by the communication device C. At this time, the room participation request includes, for example, information indicating the room location and a request to acquire an access token for accessing the distribution control device 7.

[0144] Next, the determination unit 35 of the application server 3 determines whether to change the reserved bandwidth (step S162). This process is performed when the application server 3 did not initially expect the participation of three locations and did not reserve the necessary reserved bandwidth. Specifically, the determination unit 35 of the application server 3 determines that when location C, which is included in room 1, joins, the reserved bandwidth set for room 1 does not provide room for the media distribution server 9.

[0145] Next, the transmitting / receiving unit 31 transmits information related to the room reserved bandwidth change request to the delivery control device 7 (step S163). As a result, the transmitting / receiving unit 71 of the delivery control device 7 receives the information related to the room reserved bandwidth change request transmitted by the application server 3. At this time, the room reserved bandwidth change request includes the client key, client secret, and room identification information ("R0001 ") and reserved bandwidth ("20[Mbps]").

[0146] Next, the calculation unit 73 of the distribution control device 7 calculates the margin of the reserved bandwidth (step S164). Specifically, the storage / reading unit 79 searches the room management DB 7003 (see FIG. 11) using the received room identification information ("R0001") as a search key, and reads out the corresponding media distribution server identification information ("M0091") and reserved bandwidth ("10 [Mbps]"). Note that these values ​​were added to the room management DB 7003 in the processing of step S105 described above. Thereafter, the calculation unit 73 searches the media distribution server management DB 7002 (see FIG. 10) using the media distribution server identification information ("M0091") as a search key, reads out the corresponding maximum reserved bandwidth ("100 [Mbps]"), and calculates the difference from the reserved bandwidth. When the difference from the reserved bandwidth is calculated, if the maximum reserved bandwidth is equal to or greater than the total value of the reserved bandwidth, it is determined that there is margin.

[0147] <Determining whether to change the media distribution server allocation when the room reservation bandwidth is changed> Next, the distribution control device 7 determines whether to change the proportion of media distribution servers (step S165). This determination of whether to change the proportion of media distribution servers will be described below. FIG. 19B is a flowchart showing an example of the process of determining whether to change the allocation of media distribution servers when the room reserved bandwidth is changed. First, the acquisition unit 72 acquires the reserved bandwidth that has been changed in response to the room participation requests from each location (step S165-1).

[0148] Next, the determination unit 75 determines whether the total reserved bandwidth can be accommodated by the currently assigned media distribution server (step S165-2). If the currently assigned media distribution server can accommodate the total reserved bandwidth (step S165-2: YES), the selective allocation unit 74 does not change the media distribution server allocation (keeps the currently assigned media distribution server) and exits this flow (step S165-3).

[0149] On the other hand, if the currently assigned media distribution server cannot accommodate the bandwidth (step S165-2: NO), the selective allocation unit 74 selects a media distribution server that can accommodate the updated reserved bandwidth and exits this flow (step S165-4). Specifically, the selective allocation unit 74 searches for the maximum reserved bandwidth corresponding to the media distribution server identification information managed in the media distribution server management DB 7002 (see FIG. 10), selects a media distribution server that can accommodate the total reserved bandwidth (has a maximum reserved bandwidth that is equal to or greater than the total reserved bandwidth), and exits this flow.

[0150] The above-described flowchart is merely an example, and the process for determining whether to change the media distribution server allocation when the reserved bandwidth for a room is changed is not limited to the above-described process.

[0151] 19A, the transmitting / receiving unit 71 of the delivery control device 7 transmits a room reserved bandwidth change response to the room reserved bandwidth change request of step S163 to the application server 3 (step S166). As a result, the transmitting / receiving unit 31 of the application server 3 receives the room reserved bandwidth change response transmitted by the delivery control device 7. At this time, the room reserved bandwidth change response includes information or a notification indicating that the reserved bandwidth change has been successful.

[0152] Next, the continuation of the connection processing from point C will be described. Fig. 19C is a sequence diagram showing an example of the connection processing from point C. Note that the processing from step S173 to step S177 is the same as the processing from step S113 to step S117 described above, except that the point identification information is changed from "B000A" to "B000C", and therefore description thereof will be omitted.

[0153] 19D is a sequence diagram showing an example of connection processing from location C. The transmitter / receiver C1 of the communication device C at location C transmits information related to a connection request for connecting the media distribution server to the distribution control device 7 (step S181). As a result, the transmitter / receiver 71 of the distribution control device 7 receives the information related to the connection request transmitted by the communication device C. Specifically, the transmitter / receiver C1 of the communication device C adds the client identification information and the acquired access token to the connection request and transmits it to the distribution control device 7.

[0154] Next, the verification unit 76 of the distribution control device 7 verifies the access token (step S182). Specifically, the verification unit 76 searches the client management DB 7001 (see FIG. 9) using the client identification information included in the received access token as a search key, reads out the corresponding client secret, and verifies whether it matches the client secret used when signing the access token.

[0155] Next, signature generating unit 77 generates address information for transmitting the media information (step S183). Specifically, signature generating unit 77, in cooperation with storage reading unit 79, reads out room identification information ("R0001") and base identification information ("B000C") from access token management DB 7004 (see FIG. 12). Next, signature generating unit 77 references corresponding media distribution server identification information by searching room management DB 7003 (see FIG. 11) using the room identification information ("R0001") as a search key. Furthermore, signature generating unit 77 generates address information corresponding to the referenced media distribution server identification information as address information for communication device C at base C to transmit the media information, and registers the generated address information in the corresponding address information item in media distribution server management DB 7002 (see FIG. 10).

[0156] Next, the storage / readout unit 79 adds the location identification information of Room 1 ("B000C") to the location identification information in the room management DB 7003 (see FIG. 11) (step S184).

[0157] By the processing of step S184, the following content is added to the room management DB 7003 (see FIG. 11) in addition to the content added by the processing of step S144. That is, at this point, client identification information ("C0001") is added to the content of the room management DB 7003. Then, the following items corresponding to this client identification information ("C0001") are added: room identification information ("R0001"), reserved bandwidth ("20 [Mbps]), media distribution server identification information ("M0092"), and base identification information ("B000A, B000B, B000C"). The other items corresponding to the client identification information are as shown in FIG. 11, so description thereof will be omitted.

[0158] The processing from step S185 to step S187 shown in FIG. 19D is the same as the processing from step S125 to step S127 described above, and therefore a description thereof will be omitted.

[0159] Next, the transmitter / receiver 71 of the delivery control device 7 transmits a connection response to the connection request of step S181 to the communication device C of the location C (step S188). As a result, the transmitter / receiver C1 of the communication device C receives the connection response to the connection request transmitted by the delivery control device 7. At this time, the connection response to the connection request to the media delivery server 9(2) includes address information (for example, "sfu2@example.com") of the media delivery server 9(2) for receiving media information from the location C.

[0160] Next, the transmitting / receiving unit C1 of communication device C starts transmitting media information to the connected media distribution server 9(2) (step S189). As a result, the transmitting / receiving unit 91 of media distribution server 9(2) receives information accompanying the start of transmission of the media information transmitted by communication device C. At this time, the information accompanying the start of transmission of the media information includes, for example, transmission address information of media distribution server 9(2) ("sfu2@example.com") and media information of location C.

[0161] <Reconnection process at site A> Next, the reconnection process of base A will be described. FIG. 20 is a sequence diagram showing an example of the reconnection process of base A. In this embodiment, bases A and C start transmitting media information to the transmitting address of the media distribution server that requested reconnection, and receiving media information from another base from the receiving address. In other words, the distribution control device 7 transmits to bases A and B information related to the reconnection request to the addresses to which media information from these bases will be transmitted, and to the addresses for receiving media information at another base that has already joined the room. The transmitting and receiving addresses are the addresses of the selected media distribution server 9(2).

[0162] First, the memory reading unit 79 of the distribution control device 7 searches the room management DB 7003 (see Figure 11) using the room identification information ("R0001") that has already been received as a search key, and reads out all corresponding media distribution server identification information and base identification information (step S191).

[0163] Next, the transmitter / receiver 71 transmits information related to the reconnection request from the media distribution server 9(2) to communication device A at location A (step S192). As a result, the transmitter / receiver A1 of communication device A receives the information related to the reconnection request from the media distribution server 9(2) transmitted by the distribution control device 7. At this time, the reconnection request from the media distribution server 9(2) includes transmitting address information and receiving address information of communication device C at location C.

[0164] Next, in response to the reconnection request from media distribution server 9(2) received in step S192, processing startup unit A8 of communication device A cooperates with transmission / reception unit A1 to transmit information for disconnection processing of currently connected media distribution server 9(1) (step S193). As a result, transmission / reception unit 91 of media distribution server 9(1) receives the information (data) related to the disconnection processing transmitted by communication device A.

[0165] Next, the transmitting / receiving unit A1 of communication device A transmits information related to the start of transmission of media information to the newly connected media distribution server 9(2) and starts receiving the media information from location C (step S194). As a result, the transmitting / receiving unit 91 of the media distribution server 9(2) receives the information related to the start of transmission of media information transmitted by communication device A.

[0166] Next, the transmitting / receiving unit 91 transmits the media information of the location C to the communication device A (step S195). As a result, the transmitting / receiving unit A1 of the communication device A receives the media information of the location C transmitted by the media distribution server 9(2).

[0167] Next, the display control unit A4 of the communication device A displays the media information of the location C received in step S195 on the display means (in this case, the display 407 of the display device 4) of the communication device A (step S196).

[0168] Next, the transmitter / receiver 71 of the delivery control device 7 transmits information related to the connection request of the media delivery server 9(2) to communication device C at location C (step S197). As a result, the transmitter / receiver C1 of communication device C receives the information related to the connection request of the media delivery server 9(2) transmitted by the delivery control device 7. At this time, the connection request of the media delivery server 9(2) includes receiving address information of communication device A at location A.

[0169] Next, the transmitting / receiving unit C1 of communication device C transmits information regarding the start of reception of media information from location A to media distribution server 9(2) (step S198). As a result, the transmitting / receiving unit 91 of media distribution server 9(2) receives the information regarding the start of reception of media information from location A transmitted by communication device C.

[0170] Next, the transmitting / receiving unit 91 transmits the media information of the location A to the communication device C (step S199). As a result, the transmitting / receiving unit C1 of the communication device C receives the media information of the location A transmitted by the media distribution server 9(2).

[0171] Next, the display control unit C4 of the communication device C displays the media information of the location A received in step S199 on the display means (in this case, the display 1007 of the communication terminal 10) of the communication device C (step S200).

[0172] <Reconnection process at site B> Next, the reconnection processing at location B will be described. FIG. 21A is a sequence diagram showing an example of the reconnection processing at location B. First, the transmitter / receiver 71 of the distribution control device 7 transmits information related to a reconnection request from the media distribution server 9(2) to communication device B at location B (step S202). As a result, the transmitter / receiver B1 of communication device B receives the information related to the reconnection request from the media distribution server 9(2) transmitted by the distribution control device 7. At this time, the reconnection request from the media distribution server 9(2) includes transmitting address information and receiving address information for transmitting device A at location A and communication device C at location C.

[0173] Next, in response to the reconnection request from media distribution server 9(2) received in step S202, processing startup unit B8 of communication device B cooperates with transmission / reception unit B1 to transmit information for disconnection processing of currently connected media distribution server 9(1) (step S203). As a result, transmission / reception unit 91 of media distribution server 9(1) receives the information (data) related to the disconnection processing transmitted by communication device B.

[0174] Next, the transmitting / receiving unit B1 of communication device B transmits information related to the start of transmission of media information to the newly connected media distribution server 9(2) and starts receiving media information from locations A and C (step S204). As a result, the transmitting / receiving unit 91 of media distribution server 9(2) receives the information related to the start of transmission of media information transmitted by communication device B.

[0175] Next, the transmitting / receiving unit 91 transmits the media information of the locations A and C to the communication device B (step S205). As a result, the transmitting / receiving unit B1 of the communication device B receives the media information of the locations A and C transmitted by the media distribution server 9(2).

[0176] Next, the display control unit B4 of the communication device B displays the media information of the locations A and C received in step S205 on the display means of the communication device B (in this case, the display 807 of the information processing device 8) (step S206).

[0177] Next, the reconnection process at location B will be described. FIG. 21B is a sequence diagram showing an example of the reconnection process at location B. The transmitter / receiver 71 of the distribution control device 7 transmits information related to the connection request of the media distribution server 9(2) to communication device A at location A (step S207). As a result, the transmitter / receiver A1 of communication device A receives the information related to the connection request of the media distribution server 9(2) transmitted by the distribution control device 7. At this time, the connection request of the media distribution server 9(2) includes receiving address information of communication device B at location B.

[0178] Next, the transmitting / receiving unit C1 of communication device C transmits information regarding the start of reception of media information from location B to media distribution server 9(2) (step S208). As a result, the transmitting / receiving unit 91 of media distribution server 9(2) receives the information regarding the start of reception of media information from location B transmitted by communication device C.

[0179] Next, the transmitting / receiving unit 91 transmits the media information of the location B to the communication device A (step S209). As a result, the transmitting / receiving unit A1 of the communication device A receives the media information of the location B transmitted by the media distribution server 9(2).

[0180] Next, the display control unit A4 of the communication device A displays the media information of the location B received in step S209 on the display means (in this case, the display 407 of the display device 4) of the communication device A (step S210).

[0181] Next, the transmitter / receiver 71 of the delivery control device 7 transmits information related to the connection request of the media delivery server 9(2) to communication device C at location C (step S217). As a result, the transmitter / receiver C1 of communication device C receives the information related to the connection request of the media delivery server 9(2) transmitted by the delivery control device 7. At this time, the connection request of the media delivery server 9(2) includes receiving address information of communication device B at location B.

[0182] Next, the transmitting / receiving unit C1 of communication device C transmits information regarding the start of reception of media information from location B to media distribution server 9(2) (step S218). As a result, the transmitting / receiving unit 91 of media distribution server 9(2) receives the information regarding the start of reception of media information from location B transmitted by communication device C.

[0183] Next, the transmitting / receiving unit 91 transmits the media information of the location B to the communication device C (step S219). As a result, the transmitting / receiving unit C1 of the communication device C receives the media information of the location B transmitted by the media distribution server 9(2).

[0184] Next, the display control unit C4 of the communication device C displays the media information of the point B received in step S219 on the display means of the communication device C (in this case, the display 1007 of the communication terminal 10) (step S220).

[0185] ●Screen display example● Next, a description will be given of a screen of media information shared by the communication devices at each location. FIG. 22(A) is an example of media information displayed on a display device, FIG. 22(B) is an example of media information displayed on an information processing device, and FIG. 22(C) is an example of a screen display showing an example of media information displayed on a communication terminal. In this case, in the example shown in FIG. 22(A), the display 407 of the display device 4 is divided into three, and the spatial status of the user's location A is displayed in the divided area labeled "User's Location." The spatial status of the user's location B is displayed in the divided area labeled "Location B." Furthermore, the spatial status of the user's location C is displayed in the divided area labeled "Location C." In the example shown in FIG. 22(B), the display 807 of the information processing device 8 is divided into three, and the spatial status of the user's location B is displayed in the divided area labeled "User's Location." The spatial status of the user's location A is displayed in the divided area labeled "Location A." Furthermore, the spatial status of the user's location C is displayed in the divided area labeled "Location C." In the example shown in FIG. 22(C), the display 1007 of the communication terminal 10 is divided into three, and the spatial state of the local location C is displayed in the divided area labeled "Local Location." The spatial state of the local location A is displayed in the divided area labeled "Local Location A." Furthermore, the spatial state of the local location B is displayed in the divided area labeled "Local Location B." At this time, audio at each location may be played along with the screen display of each location. Note that while FIG. 22 shows an example of screen displays at three locations, locations A, B, and C, the number of locations is not limited to this. Note that the media information in the above-mentioned screen display example is not limited to the spatial state of each location, and any image (video) including any audio in any space may be displayed.

[0186] [Major Effects of the First Embodiment] As described above, according to this embodiment, the distribution control device 7 searches the media distribution server management DB 7002 using the media distribution server identification information as a search key to read out the corresponding maximum reserved bandwidth and calculate the difference from the reserved bandwidth (step S104). Then, based on the calculated available bandwidth, it selects and assigns a media distribution server (step S105) and sends a connection request to a media distribution server 9 capable of distribution to communication device A at location A (step S125). Then, the media distribution server 9 capable of distribution transmits media information of a specified location in response to a request from a communication device at another location (step S147). This has the effect of maintaining the quality of transmission and reception of shared media information when media information is distributed between multiple locations, even if the reserved bandwidth used between the locations sharing the media information exceeds a specified bandwidth.

[0187] Furthermore, according to this embodiment, it is possible to change the reserved bandwidth of a room by using an existing media distribution server that is in operation.

[0188] Second Embodiment Next, a second embodiment will be described using Figures 23 to 26. In the second embodiment, a media distribution system will be described in which, when a room reserved bandwidth is changed and none of the existing media distribution servers can accommodate a room with the changed reserved bandwidth, a new media distribution server is added and put into operation. Note that the system configuration and hardware configuration for realizing the second embodiment are the same as those of the first embodiment, and therefore their description will be omitted. Below, the room management DB related to the functional configuration will be described in detail with reference to Figure 23, as the initial state will change.

[0189] ●Room Management Table● Fig. 23 is a conceptual diagram showing an example of a room management table. A room management DB 7003 configured by a room management table such as that shown in Fig. 11 is constructed in the storage unit 7000. This room management table has the same items as those shown in Fig. 11, but in the second embodiment, the reserved bandwidth value corresponding to the room identification information ("R0003") representing Room 3 is 90 [Mbps]. In other words, it is assumed that the media distribution server identification information ("M0092") corresponding to this reserved bandwidth, i.e., media distribution server 9(2), has a margin of only 10 [Mbps].

[0190] In this state, as in the first embodiment, client 1 creates room 1 with a reserved bandwidth of 10 Mbps, and room 1 is assigned to media distribution server 9(1). Next, sites A and B are connected in sequence, and when site C is connected, application server 3 transmits information related to a request to change the reserved bandwidth to distribution control device 7. Details of this process will be described later.

[0191] <Connection from each base (Connection from base C)> Next, a description will be given of the connection processing from the point C. Fig. 24A is a sequence diagram showing an example of the connection processing from the point C. In the sequence diagram shown in Fig. 24A, the processing from step S221 to step S224 is the same as the processing from step S161 to step S164 in Fig. 19A described above, and therefore a description thereof will be omitted.

[0192] <Determining whether to change the media distribution server allocation when the room reservation bandwidth is changed> Next, the delivery control device 7 determines whether to change the proportion of media delivery servers (step S225). This determination of whether to change the proportion of media delivery servers is described below. FIG. 24B is a flowchart showing an example of a process for determining whether to change the allocation of media delivery servers when the room reserved bandwidth is changed according to the second embodiment. First, the acquisition unit 72 acquires the reserved bandwidth that has been changed in response to a room participation request from each location (step S225-1).

[0193] Next, the determination unit 75 determines whether the total reserved bandwidth can be accommodated by the currently assigned media distribution server (step S225-2). If the currently assigned media distribution server can accommodate the total reserved bandwidth (step S225-2: YES), the selection and allocation unit 74 does not change the media distribution server allocation (keeps the currently assigned media distribution server) and exits this flow (step S225-3).

[0194] On the other hand, if the currently assigned media distribution server cannot accommodate the reserved bandwidth (step S225-2: NO), the determination unit 75 further determines whether a media distribution server that can accommodate the reserved bandwidth exists (step S225-4). If a media distribution server that can accommodate the reserved bandwidth exists (step S225-4: YES), the selective allocation unit 74 allocates the room to a media distribution server that can accommodate the reserved bandwidth and exits this flow (step S225-5). Specifically, the selective allocation unit 74, in cooperation with the storage and reading unit 79, searches the media distribution server management DB 7002 (see FIG. 10) using the current media distribution server identification information as a search key for the changed reserved bandwidth acquired in step S225-1, to read out the corresponding maximum reserved bandwidth. Next, the selection allocation unit 74 refers to the read maximum reserved bandwidth among the media distribution servers (media distribution server identification information) managed in the room management DB 7003 (see Figure 23), and allocates the room for which participation has been requested to a media distribution server that can accommodate the changed reserved bandwidth, and then exits this flow.

[0195] On the other hand, if there is no media delivery server that can accommodate the reserved bandwidth (step S225-4: NO), the selective allocation unit 74 adds a media delivery server, assigns the room for which participation has been requested to that server, and then exits this flow (step S225-6). Specifically, the selective allocation unit 74 adds a new media delivery server to the media delivery server management DB 7002 (see FIG. 10). Next, the selective allocation unit 74 also adds the added media delivery server to the room management DB 7003 (see FIG. 23), assigns the room for which participation has been requested to room identification information that corresponds to the media delivery server identification information of the added media delivery server, and then exits this flow.

[0196] 24A, the transmitter / receiver 71 of the delivery control device 7 transmits information related to the startup request to the newly assigned (added) media delivery server 9(3) (step S226). As a result, the transmitter / receiver 91 of the media delivery server 9(3) receives the information related to the startup request transmitted by the delivery control device 7.

[0197] Next, the execution unit 97 starts its own setup (step S227).

[0198] Next, the transmitter / receiver 91 transmits information related to a startup response to the information related to the startup request of step S226 to the distribution control device 7 (step S228). As a result, the transmitter / receiver 71 of the distribution control device 7 receives the information related to the startup response transmitted by the media distribution server 9. At this time, the information related to the startup response includes, for example, content indicating "setting up."

[0199] Next, the transmitting / receiving unit 71 of the delivery control device 7 transmits information related to the standby request to the application server 3 (step S229). As a result, the transmitting / receiving unit 31 of the application server 3 receives the information related to the standby request transmitted by the delivery control device 7. At this time, the information related to the standby request includes, for example, standby identification information "1". For example, a flag for the standby identification information "1" may be set by the signature generating unit 77 of the delivery control device 7 based on the content of "setting up" included in the information related to the startup response received in step S226.

[0200] In the communication system according to this embodiment, for example, when the processes of steps S226 and S228 described above are executed, other devices may exist between the delivery control device 7 and the media delivery server 9. In other words, each piece of information (data) exchanged between the delivery control device 7 and the media delivery server 9 may be exchanged once via another device. The above-described configuration is applicable even if other processing steps exist between the delivery control device 7 and the media delivery server 9.

[0201] By the processing of step S225, the following contents are added to the media distribution server management DB 7002 (see FIG. 10). That is, at this point, media distribution server identification information ("M0093") is added to the contents of the media distribution server management DB 7002. Then, the following items are added: maximum reserved bandwidth ("100 Mbps"), address information ("sfu3@example.com"), and status ("setting up") corresponding to this media distribution server identification information ("M0093"). Note that the status corresponding to both media distribution server identification information ("M0091" and "M0092") is managed as "setup complete."

[0202] <Connection from each base (Connection from base C)> Fig. 24C is a sequence diagram showing an example of connection processing from site C according to the second embodiment. The processing from step S233 to step S236 in Fig. 24 is similar to the processing from step S173 to step S176 in Fig. 19C described above (the processing from step S113 to step S116), and therefore description thereof will be omitted.

[0203] Next, the transmitting / receiving unit 31 of the application server 3 transmits information related to the standby request to the communication device C (step S237). As a result, the transmitting / receiving unit C1 of the communication device C receives the information related to the standby request transmitted by the application server 3. At this time, the information related to the standby request includes an access token and predetermined notification content to be displayed on the standby screen.

[0204] Next, the display control unit C4 of the communication device C displays the predetermined notification content received in step S237 on the display means of the communication device C (in this case, the display 1007 of the communication terminal 10) (step S238).

[0205] ●Screen display example● Next, an example of a standby screen will be described. FIG. 24D is an example of a standby screen display at base C according to the second embodiment. In this case, a predetermined notification indicating that the screen is a standby screen is displayed by the display control unit C4 on the display 1007 of the communication terminal 10, which is an example of the communication device C. The predetermined notification content is, for example, "Preparing to connect. Please wait a moment." By displaying this standby screen, the user at base C can understand that the room participation request made by the communication device C is being processed.

[0206] Next, the continuation of the connection processing from the location C will be described. FIG. 24E is a sequence diagram showing an example of the connection processing from the location C according to the second embodiment. First, the transmitting / receiving unit C1 of the communication device C transmits information related to the standby state inquiry to the application server 3 (step S241). As a result, the transmitting / receiving unit 31 of the application server 3 receives the information related to the standby state inquiry transmitted by the communication device C.

[0207] Next, the transmitting / receiving unit 31 of the application server 3 transmits (transfers) the standby status inquiry to the delivery control device 7 (step S242). As a result, the transmitting / receiving unit 71 of the delivery control device 7 receives information related to the standby status inquiry transmitted by the application server 3. At this time, the information related to the standby status inquiry includes the client key and the client secret.

[0208] Next, the acquisition unit 72 of the distribution control device 7 refers to the media distribution server management DB 7002 (see FIG. 10) to acquire the maximum reserved bandwidth and address information of each media distribution server (step S243).

[0209] Next, the transmitting / receiving unit 71 transmits information related to the standby state response as a response to the standby state inquiry received in step S242 to the application server 3 (step S244). As a result, the transmitting / receiving unit 31 of the application server 3 receives the information related to the standby state response transmitted by the distribution control device 7. At this time, the information related to the standby state response includes information indicating the status of the media distribution server 9(3) (for example, at least one of "setting up" and standby identification information "1"). In other words, this means that the standby state for communication device C has continued at this point.

[0210] Next, the transmitting / receiving unit 31 of the application server 3 transmits information related to the standby state response as a response to the standby state inquiry received in step S241 to the communication device C (step S245). As a result, the transmitting / receiving unit C1 of the communication device C receives the information related to the standby state response transmitted by the application server 3. At this time, the information related to the standby state response includes information related to the continuation of the standby screen, which indicates the status of the media distribution server 9(3).

[0211] Next, the display control unit C4 of the communication device C continues to display the content displayed in step S238 on the display 1007 of the communication terminal 10, which is an example of the communication device C (step S246).

[0212] Meanwhile, upon completion of the setup, the transmitter / receiver 91 of the media delivery server 9(3) transmits a media delivery server setup completion notification to the delivery control device 7 (step S247). As a result, the transmitter / receiver 71 of the delivery control device 7 receives the media delivery server setup completion notification transmitted by the media delivery server 9(3). At this time, the media delivery server setup completion notification includes information indicating the status of the media delivery server 9(3) (for example, "setup completed").

[0213] Next, based on the media distribution server setup completion notification received in step S247, the status management unit 78 of the distribution control device 7 changes the status item corresponding to the media distribution server identification information ("M0093") managed in the media distribution server management DB 7002 (see Figure 10) from "Setup in progress" to "Setup completed" and registers it (step S248).

[0214] Next, the continuation of the connection processing from location C will be described. Fig. 24F is a sequence diagram showing an example of the connection processing from location C according to the second embodiment. In Fig. 24F, the processing from step S251 to step S253 is the same as the processing from step S241 to step S243 shown in Fig. 24E, and therefore description thereof will be omitted. Note that the processing from step S251 onwards is repeated if the response to the standby status inquiry in step S241 described above indicates that the standby status continues.

[0215] Next, the transmitting / receiving unit 71 transmits information related to the standby state response as a response to the standby state inquiry received in step S252 to the application server 3 (step S254). As a result, the transmitting / receiving unit 31 of the application server 3 receives the information related to the standby state response transmitted by the distribution control device 7. At this time, the information related to the standby state response includes information indicating the status of the media distribution server 9(3) (for example, at least one of "setup complete" and standby identification information "0"). In other words, this means that the standby state for communication device C has been released at this point, and it is now in a connectable state.

[0216] Next, the transmitting / receiving unit 31 of the application server 3 transmits information related to the standby state response as a response to the standby state inquiry received in step S251 to the communication device C (step S255). As a result, the transmitting / receiving unit C1 of the communication device C receives the information related to the standby state response transmitted by the application server 3. At this time, the information related to the standby state response includes information related to the stop of the standby screen, which indicates the status of the media distribution server 9(3).

[0217] Next, the display control unit C4 of the communication device C stops the display of the standby screen (see FIG. 24D) that has been displayed on the display 1007 of the communication terminal 10, which is an example of the communication device C (step S256).

[0218] Next, the transmitting / receiving unit C1 of the communication device C transmits information related to the connection request to the delivery control device 7 (step S257). As a result, the transmitting / receiving unit 71 of the delivery control device 7 receives the information related to the connection request transmitted by the communication device C. At this time, the connection request includes an access token including client identification information ("C0001") indicating the client 1, room identification information, and base identification information.

[0219] The above-mentioned states of "setting up" and "setup complete" indicating the status of the media distribution server 9 may be provided (transmitted) to an external device in response to an inquiry from the external device, or may be displayed on the external device. This allows end users, including users at each location, to be notified of the setup status as it progresses, and to be asked to wait during setup.

[0220] Next, the transmitter / receiver 71 of the delivery control device 7 transmits information related to the connection request for the media delivery server 9(3) to communication device C (step S258). As a result, the transmitter / receiver C1 of communication device C receives the information related to the connection request for the media delivery server 9(3) transmitted by the delivery control device 7. At this time, the connection request for the media delivery server 9(3) includes transmission address information.

[0221] Next, the transmitting / receiving unit C1 of communication device C starts transmitting the media information to the media distribution server 9(3) (step S259). As a result, the transmitting / receiving unit 91 of the media distribution server 9(3) receives the media information transmitted by communication device C. At this time, the media information includes the transmission address information of the media distribution server 9(3) and predetermined media information.

[0222] <Reconnection process at site A> Next, the reconnection processing of site A will be described. Fig. 25 is a sequence diagram showing an example of the reconnection processing of site A according to the second embodiment. Note that the processing from step S261 to step S270 in Fig. 25 is the same as the processing from step S191 to step S200 in Fig. 20 described above, except that the connected media distribution server is changed from media distribution server (2) to media distribution server 9(3), and therefore a description thereof will be omitted.

[0223] <Reconnection process at site B> Next, a description will be given of the reconnection processing of site B. Fig. 26A is a sequence diagram showing an example of the reconnection processing of site B according to the second embodiment. Note that the processing from step S272 to step S276 in Fig. 26A is the same as the processing from step S202 to step S206 in Fig. 21A described above, except that the connected media distribution server is changed from media distribution server (2) to media distribution server 9(3), and therefore a description thereof will be omitted.

[0224] Furthermore, the processing from step S277 to step S280 in Figure 26A is the same as the processing from step S207 to step S210 in Figure 21B described above, except that the connected media distribution server is changed from media distribution server (2) to media distribution server 9(3), so the explanation will be omitted.

[0225] Next, a description will be given of the continuation of the reconnection processing at site B. Fig. 26B is a sequence diagram showing an example of the reconnection processing at site B according to the second embodiment. Note that the processing from step S282 to step S285 in Fig. 26B is the same as the processing from step S217 to step S220 in Fig. 21B described above, except that the connected media distribution server is changed from media distribution server (2) to media distribution server 9(3), and therefore a description thereof will be omitted.

[0226] Through the various processes described above in the second embodiment, the following contents are added to the room management DB 7003 (see FIG. 11). That is, at this point, client identification information ("C0001") is added to the contents of the room management DB 7003. Then, the following items are added: room identification information ("R0001"), reserved bandwidth ("20 [Mbps]), media distribution server identification information ("M0093"), and base identification information ("B000A, B000B, B000C") corresponding to this client identification information ("C0001"). The other items corresponding to the client identification information are as shown in FIG. 11, and therefore will not be described here.

[0227] [Major Effects of the Second Embodiment] As described above, according to this embodiment, when the reserved bandwidth for a room is changed and there is no media distribution server among the existing media distribution servers that can accommodate the reserved bandwidth for use of the room, a new media distribution server is added and the specified room is assigned to that media distribution server and put into operation (step S225-6). This provides the effect of the first embodiment, and also enables users at each base to make a request to join the room via a communication device without worrying about the reserved bandwidth, thereby improving the convenience of the communication system.

[0228] Third Embodiment Next, a third embodiment will be described with reference to Figures 27 to 34. In the third embodiment, a media distribution system will be described in which, when a room reserved bandwidth is changed, there is no existing media distribution server that can accommodate a room with the changed reserved bandwidth, but by moving other rooms to another media distribution server, the reserved bandwidth can be accommodated in the media distribution server.

[0229] 27 is a diagram showing an example of the overall configuration of a communication system according to the third embodiment. The communication system according to the third embodiment differs from the first and second embodiments in that a predetermined gathering point (room) including one or more locations for each client is paired with an application server to form client system 21 and client system 22. However, the hardware configuration and functional configuration of each device are the same as those of the first embodiment, and therefore description thereof will be omitted.

[0230] In the third embodiment, three media distribution servers are secured, with room 2 (90 Mbps) assigned to media distribution server 9(1), room 3 (80 Mbps) and room 4 (10 Mbps) assigned to media distribution server 9(2), and room 5 (90 Mbps) assigned to media distribution server 9(3). In other words, the initial state of the media distribution server management DB 7002 (see FIG. 10) and room management DB 7003 (see FIG. 11) is assumed to manage, for example, the following contents:

[0231] ●Media management server management table (Media distribution server management DB7002)● - Corresponds to the media distribution server identification information ("M0091"), The maximum reserved bandwidth is "100[Mbps]", the address information is "sfu1@example.com", and the status is "Setup complete". - Corresponds to the media distribution server identification information ("M0092"), The maximum reserved bandwidth is "100[Mbps]", the address information is "sfu2@example.com", and the status is "Setup complete". - Corresponds to the media distribution server identification information ("M0093"), The maximum reserved bandwidth is "100[Mbps]", the address information is "sfu3@example.com", and the status is "Setup complete". ●Room Management Table (Room Management DB7003)● - Corresponds to client identification information ("C0002"), Room identification information is "R0002", reserved bandwidth is "90[Mbps]", media distribution server identification information is "M0091", and base identification information is "B000D, B000E". - Corresponds to client identification information ("C0002"), Room identification information is "R0003", reserved bandwidth is "80[Mbps]", media distribution server identification information is "M0091", and base identification information is "B000F, B000G". - Corresponds to client identification information ("C0002"), Room identification information is "R0004", reserved bandwidth is "10[Mbps]", media distribution server identification information is "M0091", and base identification information is "B000H, B000I". - Corresponds to client identification information ("C0003"), Room identification information is "R0005", reserved bandwidth is "90[Mbps]", media distribution server identification information is "M0091", and base identification information is "B000J, B000K". In this state, as in the first embodiment, client 1 creates room 1 with a reserved bandwidth of 10 Mbps, and room 1 is assigned to media distribution server 9(1). Next, sites A and B are connected in sequence, and when site C is connected, application server 3 transmits information related to a request to change the reserved bandwidth to distribution control device 7. Details of this process will be described later.

[0232] <Connection from each base (Connection from base C)> Next, a description will be given of connection processing from the location C. Fig. 28A is a sequence diagram showing an example of connection processing from the location C according to the third embodiment. In the sequence diagram shown in Fig. 28A, the processing from step S301 to step S304 and the processing of step S306 are similar to the processing from step S221 to step S224 (processing from step S161 to step S164) and the processing of step S229 in Fig. 24A described above, and therefore description thereof will be omitted.

[0233] <Determining whether to change the media distribution server allocation when the room reservation bandwidth is changed> Here, the process of determining whether to change the proportion of media delivery servers will be described. After executing the reserved bandwidth margin calculation process in step S304, the delivery control device 7 determines whether to change the proportion of media delivery servers (step S305). This determination of whether to change the proportion of media delivery servers will be described below. Figure 28B is a flowchart showing an example of the process of determining whether to change the allocation of media delivery servers when the room reserved bandwidth is changed according to the third embodiment. First, the acquisition unit 72 acquires the reserved bandwidth that has been changed in response to room participation requests from each location (step S305-1).

[0234] Next, the determination unit 75 determines whether the total reserved bandwidth can be accommodated by the currently assigned media distribution server (step S305-2). If the currently assigned media distribution server can accommodate the total reserved bandwidth (step S305-2: YES), the selection and allocation unit 74 does not change the media distribution server allocation (keeps the currently assigned media distribution server) and exits this flow (step S305-3).

[0235] On the other hand, if the currently assigned media distribution server cannot accommodate the reserved bandwidth (step S305-2: NO), the determination unit 75 further determines whether a media distribution server capable of accommodating the reserved bandwidth exists (step S305-4). If a media distribution server capable of accommodating the reserved bandwidth exists (step S305-4: YES), the selective allocation unit 74 allocates the room to a media distribution server capable of accommodating the reserved bandwidth and exits this flow (step S305-5). Specifically, the selective allocation unit 74, in cooperation with the storage and reading unit 79, searches the media distribution server management DB 7002 (see FIG. 10) using the current media distribution server identification information as a search key for the changed reserved bandwidth acquired in step S305-1, to read out the corresponding maximum reserved bandwidth. Next, the selection allocation unit 74 refers to the read maximum reserved bandwidth among the media distribution servers (media distribution server identification information) managed in the room management DB 7003 (see Figure 23), and allocates the room for which participation has been requested to a media distribution server that can accommodate the changed reserved bandwidth, and then exits this flow.

[0236] On the other hand, if there is no media distribution server that can accommodate the reserved bandwidth (step S305-4: NO), the determination unit 75 further determines whether the reserved bandwidth can be accommodated by changing the room arrangement of the media distribution server (step S305-6). If the reserved bandwidth can be accommodated by changing the room arrangement of the media distribution server (step S305-6: YES), the selection and allocation unit 74 changes the room position of the media distribution server and exits this flow (step S305-7). Specifically, the selection and allocation unit 74 moves Room 4, which is managed in the above-mentioned room management DB 7003 (see FIG. 23), from media distribution server 9(2) to media distribution server 9(3). The processing of S305-7 following the judgment of step S305-6 described above is based on the idea that, although none of media distribution servers 9(1), 9(2), and 9(3) can accommodate a reserved bandwidth of 20 Mbps, the selective allocation unit 74 can recognize that there is room to move Room 4 (10 Mbps) to media distribution server 9(3) (using 90 Mbps). Furthermore, if the selective allocation unit 74 moves Room E from media distribution server 9(2), the reserved bandwidth surplus of media distribution server 9(2) becomes 100-80=20 Mbps, and the reserved bandwidth of Room A, which has been expanded to 20 Mbps, can be accommodated by media distribution server 9(2).

[0237] On the other hand, if the room cannot be accommodated even after changing the room arrangement of the media distribution server (step S305-6: NO), the selective allocation unit 74 adds a media distribution server, assigns the room for which participation is requested, and then exits this flow (step S305-8). Specifically, the selective allocation unit 74 adds a new media distribution server (e.g., media distribution server 9(4)) to the media distribution server management DB 7002 (see FIG. 10). Next, the selective allocation unit 74 also adds the added media distribution server 9(4) to the room management DB 7003 (see FIG. 23), and assigns the room identification information (room) corresponding to the media distribution server identification information indicating the added media distribution server 9(4) as the room for which participation is requested, and then exits this flow.

[0238] Next, the continuation of the connection processing from location C will be described. Fig. 28C is a sequence diagram showing an example of the connection processing from location C according to the third embodiment. Note that the processing from step S311 to step S316 in Fig. 28C is the same as the processing from step S233 to step S328 in Fig. 24C described above, and therefore description thereof will be omitted.

[0239] <Reconnection process at site H> Next, the reconnection processing of site H will be described. Fig. 29 is a sequence diagram showing an example of the reconnection processing of site H according to the third embodiment. Note that the processing from step S321 to step S324 in Fig. 29 is the same as the processing from step S261 to step S264 in Fig. 25 described above, except that the communication device included in the site is changed from communication device A to communication device H, and the media distribution server to be disconnected is changed from media distribution server (1) to media distribution server 9(2), and therefore a description thereof will be omitted.

[0240] <Standby status inquiry from each location (standby status inquiry from location C)> Next, the standby status inquiry process from base C will be described. Fig. 30 is a sequence diagram showing an example of the standby status inquiry process from base C according to the third embodiment. Note that the processes from step S331 to step S336 in Fig. 30 are the same as the processes from step S241 to step S246 in Fig. 24E described above, except that the media distribution server to be queried about the standby status is changed from media distribution server 9(3) to media distribution server 9(2), and therefore description thereof will be omitted.

[0241] Through the various processes described above in the third embodiment, the status corresponding to the media distribution server identification information ("M0092") in the media distribution server management DB 7002 (see FIG. 10) is registered and managed as, for example, "room allocation change in progress." The statuses corresponding to the other media distribution server identification information are maintained as "setup complete."

[0242] <Reconnection process for Site I> Next, the reconnection processing of site I will be described. Fig. 31 is a sequence diagram showing an example of the reconnection processing of site I according to the third embodiment. Note that the processing from step S342 to step S346 in Fig. 31 is the same as the processing from step S262 to step S266 in Fig. 25 described above, except for the following changes, and therefore description thereof will be omitted. The changes are that the communication device included in the site is changed from communication device A to communication device I, the media distribution server to be disconnected is changed from media distribution server 9(1) to media distribution server 9(2), and the displayed media information is changed from the media information of site C to the media information of site H.

[0243] Furthermore, the processing from step S347 to step S350 in Fig. 31 is the same as the processing from step S267 to step S270 in Fig. 25 described above, except for the following changes, and therefore description thereof will be omitted: The changes are that the communication device included in the base is changed from communication device C to communication device H, and that the displayed media information is changed from media information for base A to media information for base I.

[0244] <Standby status inquiry from each location (standby status inquiry from location C)> Next, the standby status inquiry process from location C will be described. FIG. 32 is a sequence diagram showing another example of the standby status inquiry process from location C according to the third embodiment. Note that the processes from step S351 to step S356 in FIG. 32 are the same as the processes from step S251 to step S256 in FIG. 24F described above, except that media distribution server 9(3) is changed to media distribution server 9(2), and therefore their description will be omitted. Similarly, the processes from step S361 to step S363 are the same as the processes from step S256 to step S259 in FIG. 24F described above, except that media distribution server 9(3) is changed to media distribution server 9(2), and therefore their description will be omitted.

[0245] <Reconnection process at site A> Next, the reconnection processing of site A will be described. Figure 33 is a sequence diagram showing an example of the reconnection processing of site A according to the third embodiment. Note that the processing from step S372 to step S376 in Figure 33 is the same as the processing from step S262 to step S266 in Figure 25 described above, except that media distribution server 9(3) is changed to media distribution server 9(2), and therefore a description thereof will be omitted.

[0246] Similarly, the processing from step S377 to step S380 in Figure 33 is the same as the processing from step S267 to step S270 in Figure 25 described above, except that media distribution server 9(3) is changed to media distribution server 9(2), so the explanation will be omitted.

[0247] <Reconnection process at site A> Next, the reconnection processing of site A will be described. Fig. 34A is a sequence diagram showing an example of the reconnection processing of site B according to the third embodiment. Note that the processing from step S382 to step S390 in Fig. 34A is the same as the processing from step S272 to step S280 in Fig. 26A described above, except that media distribution server 9(3) is changed to media distribution server 9(2), and therefore description thereof will be omitted.

[0248] <Reconnection process at site A> Next, the reconnection processing of site A will be described. Fig. 34B is a sequence diagram showing an example of the reconnection processing of site B according to the third embodiment. Note that the processing from step S392 to step S395 in Fig. 34B is the same as the processing from step S282 to step S285 in Fig. 26B described above, except that media distribution server 9(3) is changed to media distribution server 9(2), and therefore description thereof will be omitted.

[0249] Through the various processes described above in the third embodiment, the following contents are added to and managed in the media distribution server management DB 7002 (see FIG. 11). Specifically, - Corresponds to client identification information ("C0001"), Room identification information is "R0001", reserved bandwidth is "20[Mbps]", media distribution server identification information is "M0092", and site identification information is "B000A, B000B, B000C". As a result, in the third embodiment, allocation of an appropriate media distribution server to a room for which a connection request has been made is completed.

[0250] [Major Effects of the Third Embodiment] As described above, according to this embodiment, when the reserved bandwidth for a room is changed, if there is no media distribution server among the existing media distribution servers that can accommodate the reserved bandwidth for use of the room, the reserved bandwidth is secured by moving the other room to another media distribution server (changing the room location), and the specified room is assigned to the secured media distribution server and put into operation (step S305-7). This has the effect of the first embodiment, as well as the effect of making it possible to make maximum use of the reserved bandwidth of each media distribution server in the communication system. This makes it possible to accommodate the reserved bandwidth for a specified room without adding media distribution servers, and therefore makes it possible to optimize the costs of the media distribution system.

[0251] [Supplementary explanation of the embodiment] Each function of the above-described embodiments can be realized by one or more processing circuits. Here, the term "processing circuit" as used herein includes a device programmed by software to perform each function, such as a processor implemented by electronic circuits. Examples of such devices include a processor, an application-specific integrated circuit (ASIC), a digital signal processor (DSP), a field programmable gate array (FPGA), a system on a chip (SOC), a graphics processing unit (GPU), and conventional circuit modules designed to perform the above-described functions.

[0252] Furthermore, the various information obtained by the above-described embodiments may be obtained through the learning effects of machine learning using artificial intelligence (AI). In this case, the distribution control device may use machine learning to calculate reserved bandwidth margins, change reserved bandwidth, etc., or a device, database, or other device other than the distribution control device may obtain various information using machine learning. Here, machine learning is a technology for enabling a computer to acquire human-like learning capabilities, in which the computer autonomously creates algorithms necessary for judgments such as data identification from previously acquired learning data and applies these algorithms to new data to make predictions. The learning method for machine learning may be any of supervised learning, unsupervised learning, semi-supervised learning, reinforcement learning, and deep learning. Furthermore, the learning method for machine learning may be a combination of these learning methods, and any learning method for machine learning is not limited.

[0253] So far, we have described a media distribution system, a communication system, a distribution control device, a distribution control method, and a program according to one embodiment of the present invention, but the present invention is not limited to the above-described embodiment, and other embodiments can be added, modified, or deleted, etc., within the scope that can be conceived by a person skilled in the art, and as long as the functions and effects of the present invention are achieved in any form, it is included in the scope of the present invention. [Explanation of symbols]

[0254] 1. Communication Systems 3 Application Server 5 Media Distribution System 7 Distribution control device 9 Media distribution server 71 Transmitting / receiving unit (an example of a transmitting means, an example of a receiving means) 73 Calculation unit (an example of calculation means) 74 Selection allocation unit (an example of allocation means) 75 Judgment unit (an example of a judgment means) 77 Generated Signature Section (Example of Generation Means) 91 Transmitting / receiving unit (an example of a transmitting means, an example of a receiving means) A1 Transmitting and receiving unit (an example of a transmitting means, an example of a receiving means) B1 Transmitting / receiving unit (an example of a transmitting means, an example of a receiving means) C1 Transmitting / receiving unit (an example of a transmitting means, an example of a receiving means) A4 Display control unit (an example of a display control means) B4 Display control unit (an example of a display control means) C4 Display control unit (an example of a display control means) [Prior art documents] [Patent documents]

[0255] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-178356

Claims

1. A media distribution system including one or more media distribution servers that distribute predetermined media information to communication devices at each base, and a distribution control device that controls distribution between the communication devices at each base and the media distribution server, the media distribution server includes one or more rooms; One or more locations that share the predetermined media information are connected to the room, The distribution control device an allocation means for allocating a media distribution server selected based on a reserved bandwidth for the distribution required by a predetermined media distribution server and a maximum reserved bandwidth available to the predetermined media distribution server as a media distribution server capable of distribution to communication devices at each of the bases at a predetermined collective base including one or more bases that share the predetermined media information; a transmitting means for transmitting a connection response to a communication device of a predetermined location included in the predetermined gathering location that has transmitted a connection request for connecting to the allocated media distribution server that can distribute the media; and The media distribution server capable of distributing the media includes: a transmitting means for transmitting the predetermined media information transmitted by the communication device at the predetermined site based on the connection response transmitted by the distribution control device to a communication device at another site included in the predetermined collection site, The media distribution server controls the upload bandwidth up(i) and the download bandwidth down(i,j) of an arbitrary site i for the predetermined media information of the arbitrary site i, when the room reservation bandwidth BR of the room is given, so that the following equation (1) holds for the upload bandwidth up(i) of the arbitrary site i and the download bandwidth down(i,j) of the site j for the predetermined media information of the arbitrary site i: A media distribution system comprising: BR≧Σup(i)+Σdown(i,j)...Formula (1)

2. The allocation means If the reserved bandwidth exceeds the maximum reserved bandwidth, another media distribution server that can accommodate the reserved bandwidth is assigned instead of the predetermined media distribution server as a media distribution server that can deliver to the communication devices at each of the bases.

2. The media distribution system according to claim 1.

3. The allocation means If the reserved bandwidth exceeds the maximum reserved bandwidth, the added media distribution server is assigned to replace the predetermined media distribution server as a new media distribution server capable of distributing the predetermined media information to the communication devices at each of the bases.

2. The media distribution system according to claim 1.

4. The allocation means If the reserved bandwidth exceeds the maximum reserved bandwidth, a specific gathering point managed by the predetermined media distribution server is moved from the predetermined media distribution server to another media distribution server, and then the predetermined media distribution server is assigned as a media distribution server capable of distributing to the communication devices of each of the bases.

2. The media distribution system according to claim 1.

5. The transmission means of the distribution control device transmitting a reconnection request to reconnect to the newly allocated other media distribution server to the communication device of each of the bases included in the predetermined gathering point; 5. A media distribution system according to claim 1.

6. The distribution control device further a calculation means for calculating a difference between the reserved bandwidth and the maximum reserved bandwidth; The allocation means and allocating the reserved bandwidth to another media distribution server that can accommodate the reserved bandwidth based on the difference calculated by the calculation means.

6. A media distribution system according to claim 1.

7. The distribution control device further a determination means for determining whether the calculated reserved bandwidth can be accommodated within the maximum reserved bandwidth; The allocation means When the determination means determines that the reserved bandwidth can be accommodated in the reserved bandwidth, the media distribution server is assigned to the predetermined media distribution server, and when the determination means determines that the reserved bandwidth cannot be accommodated in the reserved bandwidth, the media distribution server is assigned to another media distribution server instead.

6. A media distribution system according to claim 1.

8. The connection response includes destination information addressed to the media delivery server capable of delivering the media, and the media delivery server capable of delivering the media further: a receiving means for receiving the destination information transmitted by the communication device at the other base; 8. A media distribution system according to any one of claims 1 to 7.

9. The distribution control device further a generation means for generating an access token including gathering point identification information for identifying the predetermined gathering point and one of predetermined base identification information for identifying the predetermined base and other base identification information for identifying the other base, based on at least one of a predetermined participation request for the predetermined gathering point transmitted by a communication device at the predetermined base and another participation request for the predetermined gathering point transmitted by a communication device at the other base, The transmission means of the distribution control device Transmitting the generated access token so that it can be received by a communication device at each of the locations included in the predetermined gathering location; 9. A media distribution system according to any one of claims 1 to 8.

10. The transmission means of the distribution control device transmitting, to the communication device of each base station, a connection response in response to a connection request, the connection response including the access token for requesting a connection to the media distribution server capable of distributing the media, transmitted from the communication device of each base station; 10. The media distribution system according to claim 9.

11. A communication system including a communication device at each base station, one or more media distribution servers that distribute predetermined media information to the communication device at each base station, and a distribution control device that controls distribution between the communication device at each base station and the media distribution server, the media distribution server includes one or more rooms; One or more locations that share the predetermined media information are connected to the room, The distribution control device an allocation means for allocating a media distribution server selected based on a reserved bandwidth for the distribution required by a predetermined media distribution server and a maximum reserved bandwidth available to the predetermined media distribution server as a media distribution server capable of distribution to communication devices at each of the bases at a predetermined collective base including one or more bases that share the predetermined media information; a transmitting means for transmitting a connection response to a communication device of a predetermined location included in the predetermined gathering location that has transmitted a connection request for connecting to the allocated media distribution server that can distribute the media; and The media distribution server capable of distributing the media includes: a transmitting means for transmitting the predetermined media information transmitted by the communication device at the predetermined site based on the connection response transmitted by the distribution control device to a communication device at another site included in the predetermined collection site, The communication device at the other base a display control means for displaying the predetermined media information transmitted by the distributable media distribution server on a display means; The media distribution server controls the upload bandwidth up(i) and the download bandwidth down(i,j) of an arbitrary site i for the predetermined media information of the arbitrary site i, when the room reservation bandwidth BR of the room is given, so that the following equation (1) holds for the upload bandwidth up(i) of the arbitrary site i and the download bandwidth down(i,j) of the site j for the predetermined media information of the arbitrary site i: A communication system comprising: BR≧Σup(i)+Σdown(i,j)...Formula (1)

12. the display control means causes the display means to display a standby screen including a predetermined standby notification content; 12. The communication system according to claim 11.

13. A distribution control device that controls distribution between a communication device at each base and one or more media distribution servers that distribute predetermined media information to the communication device at each base, the media distribution server includes one or more rooms; One or more locations that share the predetermined media information are connected to the room, an allocation means for allocating a media distribution server selected based on a reserved bandwidth for the distribution required by a predetermined media distribution server and a maximum reserved bandwidth available to the predetermined media distribution server as a media distribution server capable of distribution to communication devices at each of the bases at a predetermined collective base including one or more bases that share the predetermined media information; a transmitting means for transmitting a connection response to a communication device of a predetermined location included in the predetermined gathering location that has transmitted a connection request for connecting to the allocated media distribution server that can distribute the media; and The media distribution server controls the upload bandwidth up(i) and the download bandwidth down(i,j) of an arbitrary site i for the predetermined media information of the arbitrary site i, when the room reservation bandwidth BR of the room is given, so that the following equation (1) holds for the upload bandwidth up(i) of the arbitrary site i and the download bandwidth down(i,j) of the site j for the predetermined media information of the arbitrary site i: A distribution control device characterized by: BR≧Σup(i)+Σdown(i,j)...Formula (1)

14. A distribution control method executed by a distribution control device that controls distribution between a communication device at each base station and one or more media distribution servers that distribute predetermined media information to the communication device at each base station, comprising: the media distribution server includes one or more rooms; One or more locations that share the predetermined media information are connected to the room, an allocation step of allocating a media distribution server selected based on a reserved bandwidth for the distribution required by a predetermined media distribution server and a maximum reserved bandwidth available to the predetermined media distribution server as a media distribution server capable of distribution to communication devices at each of the bases at a predetermined collection point including one or more bases that share the predetermined media information; a transmission step of transmitting a connection response as a response to the connection request to a communication device of a predetermined location included in the predetermined gathering location that has transmitted a connection request for connecting to the allocated media distribution server that can distribute the media; Perform a process including The media distribution server controls the upload bandwidth up(i) and the download bandwidth down(i,j) of an arbitrary site i for the predetermined media information of the arbitrary site i, when the room reservation bandwidth BR of the room is given, so that the following equation (1) holds for the upload bandwidth up(i) of the arbitrary site i and the download bandwidth down(i,j) of the site j for the predetermined media information of the arbitrary site i: A distribution control method comprising: BR≧Σup(i)+Σdown(i,j)...Formula (1)

15. A program for causing a distribution control device to execute processing, the program controlling distribution between a communication device at each base and one or more media distribution servers that distribute predetermined media information to the communication device at each base, the media distribution server includes one or more rooms; One or more locations that share the predetermined media information are connected to the room, an allocation step of allocating a media distribution server selected based on a reserved bandwidth for the distribution required by a predetermined media distribution server and a maximum reserved bandwidth available to the predetermined media distribution server as a media distribution server capable of distribution to communication devices at each of the bases at a predetermined collection point including one or more bases that share the predetermined media information; a transmission step of transmitting a connection response as a response to the connection request to a communication device of a predetermined location included in the predetermined gathering location that has transmitted a connection request for connecting to the allocated media distribution server that can distribute the media; Execute a process including The media distribution server controls the upload bandwidth up(i) and the download bandwidth down(i,j) of an arbitrary site i for the predetermined media information of the arbitrary site i, when the room reservation bandwidth BR of the room is given, so that the following equation (1) holds for the upload bandwidth up(i) of the arbitrary site i and the download bandwidth down(i,j) of the site j for the predetermined media information of the arbitrary site i: program. BR≧Σup(i)+Σdown(i,j)...Formula (1)

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