JP4912451B2 - Communication system and communication method - Google Patents

Description

  INDUSTRIAL APPLICABILITY The present invention realizes a terminal device, a communication system, a terminal method, and the like that are suitable for efficiently reorganizing a tree structure when communication fails when communicating as a tree-structured node, and these are realized by a computer Related to the program.

  2. Description of the Related Art Conventionally, a technique has been proposed in which a terminal device such as a computer or a game device having a network communication function is used as a tree-structured node to form a communication network, and each node communicates efficiently.

  Here, in Patent Document 1 listed below, there is a technique that enables uplink communication toward a root node of a tree structure by performing communication with an alternative node when communication with a parent node in the tree structure is not possible. It is disclosed.

Japanese Patent No. 3842251

  Here, when providing multimedia information such as sound, moving images, game data, etc. using a tree structure, the terminal device often leaves the communication or rejoins. The quality of the communication path used varies.

  Therefore, when the provision information is propagated from the root node to the intermediate node or leaf node and the same provision information is provided to each terminal device, if communication with the parent node is not possible, there is a strong demand for a technique for appropriately selecting an alternative node. It has been.

  The present invention solves the problems as described above, and when communication fails when communicating as a tree-structured node, a terminal device, a communication system, and a communication system suitable for efficiently reorganizing the tree structure, It is an object of the present invention to provide a terminal method and a program for realizing these on a computer.

  In order to achieve the above object, the following invention is disclosed in accordance with the principle of the present invention.

  The terminal device according to the first aspect of the present invention is a node other than the root node of the tree structure having the communication device as a node, receives the provision information transmitted from the parent node, and receives the received provision information To the child node. For example, considering the case where the terminal device of the present invention receives streaming distribution of moving images and audio, the root node of the tree structure corresponds to a streaming server device, and the other nodes correspond to terminal devices. Each terminal device transmits streaming information as provision information along the branches of the tree structure in the direction from the root to the leaf, that is, in the direction from the parent node to the child node.

  The terminal device includes a selection unit, a notification transmission unit, a notification reception unit, and a parent setting unit, and is configured as follows.

  Here, when the setting of the child node of the terminal device is changed, the selection unit selects any one of the child nodes of the terminal device as the representative node, and selects another child node as the subordinate node.

  This selection is not performed when there is no child node of the terminal device. When there is only one child node, the one child node becomes a representative node and there is no subordinate node. When there are a plurality of child nodes, it is typical to select the one with the highest communication performance, for example, the one with the fast transmission / reception in the communication with the terminal device or the one with the lowest error rate.

  Further, the notification transmission unit transmits a notification designating that the parent node of the terminal device should be the substitute node to the selected representative node, and sets the selected representative node as the substitute node to the selected subordinate node. The notification specifying that it should be transmitted is transmitted, the notification receiving unit receives the notification transmitted from the parent node of the terminal device, and the parent setting unit is received when communication with the parent node of the terminal device fails. The alternative node specified in the notification is set as a new parent node.

  The notification here may be performed periodically at regular time intervals, or may be performed each time the setting of the child node is changed. Moreover, it is good also as notifying with the response with respect to the request | requirement from a child node.

  As described above, the alternative node is a terminal device that should become a new parent node when communication with the parent node becomes impossible.

  Consider a case where the parent node of a terminal device A is G, the child nodes of A are P, Q, and X, P is selected as the representative node, and Q and X are selected as subordinate nodes. , A to P are notified of G as an alternative node. From A to Q and X, P is notified as an alternative node.

  When the terminal device A is operating normally, G distributes provision information to A, and A distributes provision information to P, Q, and X. In the event that some trouble occurs, such as a failure in the terminal device A, the tree structure changes by setting the alternative node as the parent node, so that G delivers the provided information to P, and P is Q, Provision information is distributed to X.

  Thus, according to the present invention, when communication with the parent node becomes impossible, provision of information can be continued efficiently only by locally updating the tree structure.

  The terminal device of the present invention further includes a request transmission unit, a response reception unit, a request reception unit, a child setting unit, and a response transmission unit, and can be configured as follows.

  Here, the request transmitting unit transmits a request for providing information to the parent node of the terminal device, and the response receiving unit receives a response specifying the providing information transmitted from the parent node of the terminal device.

  In the above example, the request corresponds to another terminal device set as a parent node in the terminal device or a streaming server device, and the provided information corresponds to moving image information that is streamed. As will be described later, the parent node can be changed as appropriate.

  In addition, a response is returned in response to the request transmitted to the parent node, and the provision information is included in the response. Note that a form in which “notification” described later is transmitted and received together with the provision information may be adopted.

  Typically, the received provision information is provided to the user. In the above example, the streaming-distributed moving image is displayed on the screen, and the sound is output from the speaker or the headphone so that the user can watch it.

  Further, the request receiving unit receives a request for providing information transmitted from another terminal device, and the child setting unit sets the terminal device that is the source of the received request as a child node of the terminal device, The response transmission unit is a child node of the terminal device, and transmits a response specifying the provision information to the terminal device that is the transmission source of the received request.

  The request transmission unit and the response reception unit described above operate so that the terminal device functions as a “child node”, but the request reception unit, the child setting unit, and the response transmission unit function as a “parent node”. Will work for. Note that the number of child nodes to be set is any number from 0 to a predetermined upper limit, and the setting of child nodes is typically canceled as will be described later.

  And a selection part will perform selection again, if the setting of the child node of a terminal device is changed.

  According to the present invention, a child node is set when a request from another terminal apparatus arrives, and a representative node can be appropriately selected according to the latest situation.

  Further, in the terminal device of the present invention, when communication with the child node of the terminal device fails, the child setting unit can be configured to cancel the setting of the child node for which the communication has failed. In addition, when communication with a certain child node is not performed for a certain period of time, the setting of the child node is typically canceled.

  In the present invention, the parent-child relationship is established only when there is a request from the side seeking distribution of the provided information, but when the parent node tries to send a response or notification to the child node and failure continues to some extent, Cancel the child node settings.

  When the setting of the child node is canceled, the setting of the child node is changed, so that the selection unit re-selects the representative node and the subordinate node. As a result, the alternative node is reset in the child node that can currently communicate from the parent node.

  According to the present invention, it is possible to appropriately set an alternative node in a child node.

  Further, in the terminal device of the present invention, when communication with another terminal device is performed via a computer communication network and communication with the computer communication network is disabled, the child setting unit Cancels all the child node settings that have already been set, and the parent setting unit can be configured to set the selected representative node as a new parent node.

  Here, when communication with the computer communication network becomes impossible, when the terminal device is turned off, when the network communication cable of the terminal device is disconnected, the wireless LAN (Local Area Network) This means when communication becomes impossible due to congestion or noise, or when a router, firewall, or Internet service provider used by a terminal device stops operating. In such a case, the terminal device cannot communicate with any of the parent node, the alternative node, and the child node. In general, it takes a certain amount of time for the above-described problems to be resolved and communication to be established again.

  In such a case, it is highly likely that a new tree structure excluding the terminal device has already been formed. Therefore, the terminal device that has returned to the computer communication network sets the terminal device that was once selected as the representative node as a new parent node.

  By adopting such a configuration, the tree structure is naturally changed so that the terminal devices that have been stably participating in the tree structure have a longer time and are arranged upstream.

  According to the present invention, provided information can be distributed efficiently even when a terminal device that has become unable to communicate due to a power failure or the like is restored.

  The terminal device of the present invention further includes a determination unit, an introduction transmission unit, and an introduction reception unit, and can be configured as follows.

  In other words, when the request is received from a terminal device that is not set as a child node of the terminal device, the determination unit creates a new child node based on the number of child nodes already set in the terminal device or the communication amount of the terminal device. It is determined whether or not to set.

  That is, based on the number of terminal devices that a certain terminal device can make as a child node and the current communication volume, the communication load of the terminal device is predicted and it is determined whether or not the communication load can be withstood.

  When the determination unit determines that a new child node is not set, the introduction transmission unit transmits an introduction designating one of the child nodes of the terminal device to the request source terminal device, and the introduction The receiving unit receives the introduction transmitted from the terminal device to which the request is transmitted.

  That is, there are cases where a response specifying the provision information is returned to the terminal apparatus that has transmitted the request for the provision information, and an introduction designating another terminal apparatus is transmitted.

  Here, when the determination unit determines to set a new child node, the child setting unit sets the terminal device that has transmitted the request to the child node. This is a case where it is determined that the terminal device can withstand the communication load, and the terminal device functions in the same manner as the above-described invention.

  On the other hand, when the introduction is received by the introduction receiving unit, the parent setting unit sets the terminal device designated for the introduction as the parent node.

  This is a case where the terminal device to which the request is transmitted cannot determine the communication load and sends an introduction instead of a response. The terminal device retransmits the other terminal device to the parent node. Set and resend the request.

  According to the present invention, a new terminal device can be arranged at an appropriate position in the tree structure in accordance with the communication performance and communication status of the terminal devices constituting the tree-structured node.

  A communication system according to another aspect of the present invention includes the terminal device, the instruction server device, and the providing server device, and is configured as follows. Typically, one or a plurality of providing server devices are provided, and a different communication device is used as the instruction server device.

  That is, when communication with the parent node that has been an alternative node fails, the terminal device requests an instruction server device and sets the communication device instructed by the instruction server device as the parent node.

  That is, when the communication with the parent node fails and the communication with the alternative node also fails, the terminal device asks the instruction server device for an instruction as to which communication device should be the parent node.

  On the other hand, when the instruction server device requests an instruction from the terminal device, the instruction server device selects either the providing server device or the terminal device that has already given the instruction, and issues an instruction that the selected communication device should be the parent node. This is given to the terminal device.

  The instruction server device is a device that gives an instruction as to which communication device should be a parent node when receiving distribution of provided information. As the communication device, a terminal device that has already participated in the tree structure may be employed, or a providing server device that is a root node of the tree structure may be employed.

  Further, when the providing server device receives a request for providing information from a terminal device, the providing server device transmits a response specifying the providing information to the terminal device.

  That is, the providing server device functions as a root node of the tree structure and provides providing information to each terminal device.

  ADVANTAGE OF THE INVENTION According to this invention, the communication system which transmits provision information to a terminal device efficiently using a tree structure can be provided.

  Further, in the communication system of the present invention, when the instruction server device is requested for an instruction from the terminal device, if there is no terminal device that has given the instruction within a predetermined period from the present time, the instruction server device selects the providing server device, and starts the predetermined period from the present time. If there is a terminal device that gives an instruction, it can be configured to randomly select from the terminal device.

  In general, for terminal devices that have recently joined a tree structure recently and terminal devices that have previously participated in the tree structure and have continued to participate, It is considered to participate in the structure.

  Therefore, assuming that a terminal device that has given an instruction within a predetermined period from now will participate in the tree structure for a long time, this is instructed as a parent node.

  Note that the situation in which there is no terminal device that has given an instruction within a predetermined period from now is considered that communication is performed smoothly, the load is low, and congestion does not occur. I am going to tell you as.

  According to the present invention, a tree structure can be appropriately configured according to a situation in which a terminal device requests an instruction of a parent node.

  The terminal method according to another aspect of the present invention is a node other than a root node of a tree structure having the communication device as a node, receives the provision information transmitted from the parent node, and receives the received provision information Is transmitted to a child node and executed by a terminal device including a selection unit, a notification transmission unit, a notification reception unit, and a parent setting unit, and the terminal method includes a selection step, a notification transmission step, a notification reception step, and a parent setting step. The configuration is as follows.

  Here, in the selection step, the selection unit selects any one of the child nodes of the terminal device as a representative node, and selects another child node as a subordinate node.

  On the other hand, in the notification transmission step, the notification transmission unit transmits a notification designating that the parent node of the terminal device should be an alternative node to the selected representative node, and the selected representative node is selected. Sends a notification specifying that the node should be an alternate node.

  Further, in the notification receiving step, the notification receiving unit receives a notification transmitted from the parent node of the terminal device.

  When communication with the parent node of the terminal device fails, in the parent setting step, the parent setting unit sets the alternative node specified in the received notification as a new parent node.

  A program according to another aspect of the present invention is configured to cause a computer to function as the terminal device.

  The program of the present invention can be recorded on a computer-readable information storage medium such as a compact disk, flexible disk, hard disk, magneto-optical disk, digital video disk, magnetic tape, and semiconductor memory.

  The above program can be distributed and sold via a computer communication network independently of the computer on which the program is executed. The information storage medium can be distributed and sold independently from the computer.

  ADVANTAGE OF THE INVENTION According to this invention, when communication fails when it becomes a tree-structured node, a terminal device, a communication system, a terminal method, and these suitable for efficiently reorganizing the tree structure are provided to a computer. Can be provided.

It is a schematic diagram which shows schematic structure of a typical information processing apparatus. It is a mimetic diagram showing the outline composition of the communications system concerning this embodiment. It is a session diagram of communication when a new terminal device tries to participate in a tree structure. It is explanatory drawing which shows schematic structure of the terminal device which concerns on this embodiment. It is a flowchart which shows the flow of control of the terminal process performed with the terminal device which concerns on this embodiment. It is a flowchart which shows the flow of control of the terminal process performed with the terminal device which concerns on this embodiment. It is a flowchart which shows the flow of control of the terminal process performed with the terminal device which concerns on this embodiment. It is explanatory drawing which shows the state of a tree structure. It is explanatory drawing which shows the state of a tree structure. It is explanatory drawing which shows schematic structure of an instruction | indication server apparatus. It is a flowchart which shows the flow of control of the instruction | indication process performed in an instruction | indication server apparatus. It is explanatory drawing which shows schematic structure of a provision server apparatus. It is a flowchart which shows the flow of control of the provision process performed in a provision server apparatus.

  Embodiments of the present invention will be described below. In the following, for ease of understanding, an embodiment in which the present invention is realized using a game information processing device will be described. However, the embodiment described below is for explanation, and the present invention is described. It does not limit the range.

  Therefore, those skilled in the art can employ embodiments in which each or all of these elements are replaced with equivalent ones, and these embodiments are also included in the scope of the present invention.

  FIG. 1 is a schematic diagram illustrating a schematic configuration of a typical information processing apparatus that can function as a server apparatus such as a terminal apparatus, an instruction server apparatus, and a providing server apparatus in the communication system according to the present embodiment by executing a program. is there. Hereinafter, a description will be given with reference to FIG.

  An information processing apparatus 100 shown in the figure corresponds to a so-called consumer game machine, and includes a central processing unit (CPU) 101, a read only memory (ROM) 102, a random access memory (RAM) 103, an interface 104, a controller 105, An external memory 106, an image processing unit 107, a DVD-ROM (Digital Versatile Disc ROM) drive 108, a NIC (Network Interface Card) 109, an audio processing unit 110, a microphone 111, and a hard disk (HD) 121 are included. Various input / output devices can be omitted as appropriate.

  When the information processing apparatus 100 is caused to function as a typical consumer game machine, a DVD-ROM storing a game program and data is mounted on the DVD-ROM drive 108 and the power is turned on. Then, the game program is executed and the game can be played.

  However, in the present embodiment, typically, an application is installed in the HD 121 from a DVD-ROM attached to the DVD-ROM drive 108. Then, by executing the program stored in the HD 121, various applications including a game are executed.

  Further, as will be described later, the terminal device and the server device differ only in the scale and type of information processing to be executed. Essentially, both have the same configuration as the information processing device 100 shown in FIG. Realized.

  In order to make the portable game device portable, the DVD-ROM drive 108 is not used, but an EEPROM (Electrically Erasable Programmable ROM) cassette is mounted in the ROM cassette slot and the HD 121 is mounted. It can also be omitted. In this case, the application program is written in the EEPROM cassette and then the program is executed. In addition, an application program can be installed in the external memory 106.

  The CPU 101 controls the overall operation of the information processing apparatus 100 and is connected to each component to exchange control signals and data. Further, the CPU 101 uses arithmetic operations such as addition / subtraction / multiplication / division, logical sum, logical product, etc. using an ALU (Arithmetic Logic Unit) (not shown) for a storage area called a register (not shown) that can be accessed at high speed. , Logic operations such as logical negation, bit operations such as bit sum, bit product, bit inversion, bit shift, and bit rotation can be performed. In addition, the CPU 101 itself is configured so that saturation operations such as addition / subtraction / multiplication / division for multimedia processing, vector operations such as trigonometric functions, etc. can be performed at a high speed, and those provided with a coprocessor. There is.

  The ROM 102 records an IPL (Initial Program Loader) that is executed immediately after the power is turned on, and when this is executed, the program recorded on the DVD-ROM is read out to the RAM 103 and execution by the CPU 101 is started. The The ROM 102 stores an operating system program and various data necessary for operation control of the entire information processing apparatus 100.

  The RAM 103 is for temporarily storing data and programs, and retains programs and data read from the HD 121 and DVD-ROM, and other data necessary for the progress of the communication battle game and chat communication. Further, the CPU 101 provides a variable area in the RAM 103 and performs an operation by directly operating the ALU on the value stored in the variable, or temporarily stores the value stored in the RAM 103 in the register. Perform operations such as performing operations on registers and writing back the operation results to memory.

  The controller 105 connected via the interface 104 receives an operation input performed when the user executes the game.

  The controller 105 does not necessarily have to be externally attached to the information processing apparatus 100, and may be formed integrally. The controller 105 of the portable terminal device includes various buttons and switches, and handles these pressing operations as operation inputs. In addition, in the information processing apparatus 100 using the touch screen, the user traces the trace of the touch screen using a pen or a finger as an operation input.

  The external memory 106 detachably connected via the interface 104 stores data indicating game play status (past results, etc.), data indicating the progress of the game, and log of chat communication in a network battle ( Data) is stored in a rewritable manner. The user can record these data in the external memory 106 as appropriate by inputting an instruction via the controller 105.

  As described above, it is possible to adopt a form in which the application program is installed in the external memory 106 and executed. This is suitable when the external memory 106 has a large capacity.

  A DVD-ROM mounted on the DVD-ROM drive 108 stores a program for realizing the game and image data and audio data associated with the game. Under the control of the CPU 101, the DVD-ROM drive 108 performs a reading process on the DVD-ROM loaded therein, reads out necessary programs and data, and these are temporarily stored in the RAM 103 or the like.

  The image processing unit 107 processes the data read from the DVD-ROM by an image arithmetic processor (not shown) included in the CPU 101 or the image processing unit 107, and then processes the processed data on a frame memory ( (Not shown). The image information recorded in the frame memory is converted into a video signal at a predetermined synchronization timing and output to a monitor (not shown) connected to the image processing unit 107. Thereby, various image displays are possible.

  As a monitor of a portable terminal device, a small liquid crystal display is typically used. When a touch screen is used as the controller 105, the display panel of the touch screen functions as a monitor. A display device such as a CRT (Cathode Ray Tube) or a plasma display can be used as a monitor for a terminal device or a server device for playing at home.

  The image calculation processor can execute a two-dimensional image overlay calculation, a transmission calculation such as α blending, and various saturation calculations at high speed.

  Also, polygon information arranged in the virtual three-dimensional space and added with various texture information is rendered by the Z buffer method, and the polygon arranged in the virtual three-dimensional space from the predetermined viewpoint position is determined in the direction of the predetermined line of sight It is also possible to perform high-speed execution of operations for obtaining rendered images.

  Further, the CPU 101 and the image arithmetic processor operate in a coordinated manner, so that a character string can be drawn as a two-dimensional image in a frame memory or drawn on the surface of each polygon according to font information that defines the character shape. is there.

  The NIC 109 is used to connect the information processing apparatus 100 to a computer communication network (not shown) such as the Internet, and conforms to the 10BASE-T / 100BASE-T standard used when configuring a LAN. An analog modem for connecting to the Internet using a telephone line, an ISDN (Integrated Services Digital Network) modem, an ADSL (Asymmetric Digital Subscriber Line) modem, a cable modem for connecting to the Internet using a cable television line, etc. These are configured by an interface (not shown) that mediates between these and the CPU 101.

  An application program can be installed in the HD 121 or the like based on information obtained from the computer communication network via the NIC 109.

  The audio processing unit 110 converts audio data read from the HD 121 or DVD-ROM into an analog audio signal, and outputs the analog audio signal from a speaker (not shown) connected thereto. Further, under the control of the CPU 101, sound effects and music data to be generated during the progress of the game are generated, and the corresponding sound is output from a speaker, headphones (not shown), and earphones (not shown). Output.

  When the audio data recorded on the HD 121 or the DVD-ROM is MIDI data, the audio processing unit 110 refers to the sound source data included in the audio data and converts the MIDI data into PCM data. If the compressed audio data is in ADPCM format or Ogg Vorbis format, it is expanded and converted to PCM data. The PCM data can be output by performing D / A (Digital / Analog) conversion at a timing corresponding to the sampling frequency and outputting it to a speaker.

  Furthermore, a microphone 111 can be connected to the information processing apparatus 100 via the interface 104. In this case, the analog signal from the microphone 111 is subjected to A / D conversion at an appropriate sampling frequency so that processing such as mixing in the sound processing unit 110 can be performed as a PCM format digital signal.

  As described above, the information processing apparatus 100 used in the present embodiment typically uses a large-capacity external storage device such as the HD 121. The HD 121 can also perform the same functions as a DVD-ROM or the like mounted on the ROM 102, RAM 103, external memory 106, DVD-ROM drive 108, and the like.

  In addition, it is possible to adopt a form in which a keyboard for accepting a character string editing input from a user, a mouse for accepting various position designations and selection inputs, and the like are connected. In addition, a general-purpose personal computer, a server computer, or the like can be used instead of the information processing apparatus 100 of the present embodiment.

  Further, in the present embodiment, a function for inquiring the time to an NTP (Network Time Protocol) server via a real-time clock (not shown) or the NIC 109 is adopted, and the date and time when the information processing apparatus 100 is used. We are going to use information.

  The information processing apparatus 100 described above corresponds to a consumer game apparatus, but the terminal apparatus and server apparatus of the present invention can be realized as long as the electronic apparatus can perform various input / output processes. . Therefore, the terminal device and server device of the present invention can be realized on various computers such as a mobile phone, a mobile game device, a karaoke device, and a general business computer.

  For example, similarly to the information processing apparatus 100, the business computer has a CPU, RAM, ROM, DVD-ROM drive, NIC, and HD as constituent elements, and has simpler functions than the information processing apparatus 100. In addition, a flexible disk, a magneto-optical disk, a magnetic tape, etc. can be used as an external storage device, and it is typical to use a keyboard or mouse as an input device instead of the controller 105. is there.

(Communications system)
FIG. 2 is an explanatory diagram showing a schematic configuration of the communication system according to the embodiment of the present invention. Hereinafter, a description will be given with reference to FIG.

  The communication system 201 of the present embodiment includes a terminal device 221, an instruction server device 241, and a providing server device 261, and appropriately communicates with each other within the Internet 291.

  The terminal device 221 is used by general users such as consumer game devices and personal computers, and the instruction server device 241 is a server computer similar to a lobby server and matching server in an online game, and a providing server device 261 Is a server computer that performs various data distribution such as streaming distribution.

  In the present embodiment, streaming information such as a moving image and audio is provided to each terminal device 221 directly from the providing server device 261 or indirectly via another terminal device 221. The communication system 201 including the terminal device 221 and the providing server device 261 has a so-called tree structure. The root node of the tree structure corresponds to the providing server device 261, the other intermediate nodes and leaf nodes correspond to the terminal devices 221, and the branches connecting the nodes in the tree structure correspond to communication paths when providing streaming information. To do.

  If the terminal device 221 is an intermediate node, the terminal device 221 receives streaming information from the parent node, presents the streaming information to the user of the terminal device 221, and transmits the streaming information to the child node.

  If the node itself is a leaf node, it receives streaming information from the parent node and presents the streaming information to the user of the terminal device 221.

In this figure,
(1) The terminal device 221 (intermediate node G) is included in the child nodes of the providing server device 261 (root node R),
(2) The terminal device 221 (intermediate node A) is included in the child nodes of the terminal device 221 (intermediate node G),
(3) Child devices of the terminal device 221 (intermediate node A) include the terminal device 221 (leaf node P), the terminal device 221 (leaf node Q), and the terminal device 221 (leaf node X).
In this order, streaming information is relayed in the order of root node R → intermediate node G → intermediate node A → leaf node P / leaf node Q / leaf node X.

  In general, the number of child nodes when one terminal device 221 becomes a parent node is limited depending on the communication environment and communication performance of the terminal device 221 of the parent node. Therefore, in the present embodiment, when a new terminal device 221 (node X) tries to participate in the tree structure for the first time, the following procedure is taken.

  The provided information distributed to the terminal device 221 is not limited to the streaming information as described above, and the present embodiment can be applied to distribution of various information such as programs, data, and various types of multimedia information. .

  FIG. 3 is a communication session diagram when a new terminal device attempts to participate in the tree structure. Hereinafter, a description will be given with reference to FIG.

  When the terminal device 221 (node X) does not know which device should be adopted as the parent node, the terminal device 221 (node X) transmits an inquiry for an instruction to the instruction server device 241 (301). Therefore, generally, the communication identifier expressed by the host name or IP address of the instruction server device 241 (and the port number used for communication in the case where the communication port is variable) is fixed.

  The instruction server device 241 that has been requested to send an instruction specifies an instruction specifying the communication identifier of the providing server device 261 or another terminal device 221 that is expected to be currently distributed in the tree structure. It transmits to the terminal device 221 (302).

  Since such a configuration is adopted, the number of providing server devices 261 is not limited to one, and the number can be increased or decreased as appropriate. When the load is low, the providing server device 261 and the instruction server device 241 can be configured by the same server device.

  In the following description, it is assumed that the terminal device 221 that is the intermediate node G is specified in the instruction.

  The terminal device 221 (node X) having received the instruction transmits a request for streaming information to the intermediate node G in order to participate in the tree structure with the instructed intermediate node G as a parent node (303).

  In the following description, it is assumed that the intermediate node G determines that the node X cannot be its own child node as a result of considering the number of its own child nodes and the communication environment.

  In this case, the intermediate node G transmits an introduction designating one of its child nodes to the node X (304). Which one to select from the child nodes can be selected, for example, randomly or in the order of its own child nodes, or by checking the communication status with each child node, It is possible to adopt various modes such as selecting the best one. In the following description, it is assumed that the intermediate node A is designated for the introduction.

  The node X that has received the introduction transmits a request for streaming information to the intermediate node A designated for the introduction (305).

  Assuming that the intermediate node A determines that the node X can be its own child node as a result of considering the number of child nodes and the communication environment, the intermediate node A receives a response specifying streaming information. The node X becomes a leaf node having the intermediate node A as a parent node (306).

  Thereafter, by repeatedly transmitting a request from the child node X to the parent node A and transmitting a response from the node A to the node X, the streaming information is transmitted from the root node of the tree structure. Delivered down the node.

  In this embodiment, when a leaf node receives a request, the leaf node becomes a parent node (that is, an intermediate node), and the transmission source of the request becomes a child node. Therefore, the position of the terminal device 221 that intends to newly participate in the tree structure is always determined somewhere in the tree structure.

  Hereinafter, first, details of the terminal device 221 according to the present embodiment will be described, and then the instruction server device 241 and the providing server device 261 will be described.

(Terminal device)
FIG. 4 is an explanatory diagram showing a schematic configuration of the terminal device 221 according to the present embodiment. Hereinafter, a description will be given with reference to FIG.

  The terminal device 221 includes a setting storage unit 401, an inquiry transmission unit 402, an instruction reception unit 403, a request transmission unit 404, a response reception unit 405, a provision unit 406, a request reception unit 407, a child setting unit 408, a response transmission unit 409, a selection Unit 410, notification transmission unit 411, notification reception unit 412, parent setting unit 413, determination unit 415, introduction transmission unit 416, and introduction reception unit 417.

Here, the setting storage unit 401 typically stores the following information in a nonvolatile manner.
(A) The communication identifier of the parent node of the terminal device 221.
(B) The communication identifier of the alternative node.
(C) A communication identifier of a child node of the terminal device 221.

  As information (a) and (b), it is possible to determine whether a communication identifier for one device is stored or whether it is in an unset state, and as information (c), there are zero or more communication identifiers. Is typically stored.

  Since these pieces of information (particularly parent node information (a) and alternative node information (b)) refer to previously set values when the terminal device 221 is turned on, the setting storage unit 401 is preferably configured by an external memory 106 or a hard disk so that information can be stored in a nonvolatile manner. However, in an aspect where the communication state changes from moment to moment, even if the setting storage unit 401 is configured by the RAM 103, a sufficient effect can be obtained.

  Hereinafter, the function of each unit will be described with reference to the procedure of processing executed by each unit. 5, 6 and 7 are flowcharts showing the flow of control of terminal processing executed by the terminal device 221 according to the present embodiment.

  When the terminal device 221 is powered on, the terminal device 221 refers to the setting storage unit 401 and checks whether or not the communication identifier of the parent node is stored (step S501).

  If the user has participated in the tree structure in the past and the setting storage unit 401 is non-volatile, the communication identifier of the parent node at the previous participation is obtained here.

  When the communication identifier of the parent node is not stored (step S501; No), the inquiry transmission unit 402 determines which communication device should be the parent node with respect to the instruction server device 241 having the fixed communication identifier. The inquiry requesting the instruction is transmitted (step S502), and the instruction receiving unit 403 receives the instruction transmitted from the instruction server device 241 in response to the inquiry (step S503).

  Therefore, the NIC 109 functions as the inquiry transmission unit 402 and the instruction reception unit 403 under the control of the CPU 101.

  As described above, in the instruction transmitted from the instruction server device 241, the communication identifier of another terminal device 221 or the providing server device 261 that is highly likely to participate in the tree structure is specified. Therefore, the parent setting unit 413 updates the setting storage unit 401, stores the communication identifier specified in the instruction as the communication identifier of the parent node, and sets it as the parent node of the terminal device 221 (step S504).

  Therefore, the CPU 101 functions as the parent setting unit 413 in cooperation with the external memory 106 and the like. The parent setting unit 413 also functions to execute various processes described later.

  Then, the CPU 101 clears the buffer prepared in the RAM 103 (step S507), and the image processing unit 107 and the audio processing unit 110 start processing for reproducing multimedia information stored in the buffer in parallel. After (step S508), the process proceeds to step S509.

  On the other hand, when the communication identifier of the parent node is stored (step S501; Yes), the process proceeds to step S509.

  This buffer temporarily stores streaming information, and by performing buffering, it is possible to prevent the moving image and sound presented to the user from being interrupted as much as possible. After a certain amount of information is accumulated in the buffer, playback of a moving image or the like is started, and thereafter, information accumulated in the buffer is sequentially provided to the user. Further, the streaming information is held in the buffer for a certain period, and is appropriately redistributed to the child nodes in response to a request from the child node of the terminal device 221.

  As described above, the CPU 101, the RAM 103, the image processing unit 107, and the audio processing unit 110 work together to realize the providing unit 406. The providing unit 406 monitors the buffer and sends streaming information to the user as a moving image. And serve as audio.

  The CPU 101 checks whether or not the streaming information that has not been reproduced yet remains in the buffer, that is, whether or not the buffering is sufficient (step S509). If buffering is sufficient (step S509; Yes), the process proceeds to step S511.

  If the buffering is not sufficient (step S509; No), the request transmission unit 404 transmits a request for streaming information to the currently set parent node (step S510).

  Then, the terminal device 221 waits until some packet is received by the NIC 109, some error occurs, or the buffering state changes (step S511). During this standby, other processing is performed as appropriate, for example, decoding processing of information necessary for reproduction of moving images and audio stored in the buffer in the RAM 103, and processing of the audio processing unit 110 and the image processing unit 107. Control and the like can be executed in a coroutine manner.

  Accordingly, the NIC 109 functions as the request transmission unit 404 under the control of the CPU 101.

  When the standby in step S511 ends, the CPU 101 checks the cause (step S512). Possible causes are as follows.

   (1) When the introduction transmitted from the parent node is received in response to the request transmitted from the terminal device 221 to the parent node (step S512; introduction). In this case, the NIC 109 functions as the introduction receiving unit 417.

   (2) When a response transmitted from the parent node is received in response to the request transmitted by the terminal device 221 (step S512; response). In this case, the NIC 109 functions as the response reception unit 405.

   (3) When a notification transmitted from the parent node is received (step S512; notification). In this case, the NIC 109 functions as the notification receiving unit 412.

   (4) When a request transmitted from another terminal device 221 is received (step S512; request). In this case, the NIC 109 functions as the request reception unit 407.

   (5) When an error has occurred (step S512; error). An error occurs when a packet is sent and an acknowledgment is expected to be returned, but no acknowledgment is received for that transmission, or a protocol that does not return an acknowledge is used. Even if the packet from the other party does not reach for a long time, etc., such as when the destination communication device has stopped operating, the router to which the NIC 109 is connected, a firewall or Internet connection The case where some trouble occurs in the provider is considered. Moreover, the case where an error is notified from the communication partner is also included.

   (6) When information in the buffer is consumed and its state changes (step S512; buffer).

  When a packet of a type other than the above is received, a corresponding process is executed as appropriate (not shown).

  The case where an introduction is received despite the transmission of a request to another terminal device 221 (step S512; introduction) is a case where a parent-child relationship with the other terminal device 221 cannot be created. is there. At this time, the communication identifier of another terminal device 221 to be the parent node is designated in the introduction. Therefore, the parent setting unit 413 resets the parent node by storing the communication identifier designated for introduction as the parent node in the setting storage unit 401 (step S513), and returns to step S511.

  On the other hand, when a response is received from the parent node (step S512; response), the streaming information specified in the response is added to the buffer (step S514), and the process returns to step S509. This streaming information is provided to the user by the providing unit 406.

  On the other hand, if the buffer status has changed (step S512; buffer), the process immediately returns to step S511.

  When a notification is received from the parent node (step S512; notification), the notification includes a communication identifier of “a communication device to be newly set as a parent node when communication with the parent node becomes impossible in the future”. It is specified. Therefore, the CPU 101 stores the communication identifier designated in the notification in the setting storage unit 401 as an alternative node (step S515), and returns to step S511. A method for determining the information specified in the notification will be described later.

  In addition, if an error occurs (step S512; error), whether the cause is only communication with the parent node, communication with a certain child node, or other reasons why communication is not possible. It investigates (step S516).

  When communication with the parent node is the cause (step S516; parent), the parent setting unit 413 checks whether or not the information on the alternative node is stored in the setting storage unit 401 (step S517) and stores it. If this is the case (step S517; Yes), the setting storage unit 401 stores the communication identifier of the alternative node as the parent node (step S518), deletes the information of the alternative node (step S519), and returns to step S509.

  In the above configuration, when communication with the parent node becomes impossible, the alternative node once introduced to the parent node becomes a new parent node of the terminal device 221 and the shape of the tree structure is updated. Then, the process of transmitting a request for streaming information to the new parent node and waiting for a response is repeated.

  On the other hand, if communication with the parent node is the cause (step S516; parent) and the information on the alternative node is not stored (step S517; No), the process returns to step S502. As a result, the terminal device 221 receives a new parent node instruction from the instruction server device 241.

  In this case as well, the shape of the tree structure is updated. As will be described later, by selecting an appropriate terminal device 221 to be introduced as an alternative node, the inquiry server 241 can be concentrated. Another feature of the present invention is that it can be prevented as much as possible.

  Hereinafter, a situation in which the terminal device 221 transmits a response, introduction, and notification will be described in detail.

  First, when the NIC 109 receives a request from another terminal device 221 (step S512; request), the CPU 101 stores the terminal device 221 that has transmitted the request as a child node in the setting storage unit 401. It is checked whether or not (step S520).

  When stored as a child node (step S520; Yes), the response transmission unit 409 acquires necessary streaming information from the buffer in the RAM 103 in response to the request (step S521), and the streaming information Is transmitted to the child node (step S522), and the process returns to step S509.

  Accordingly, under the control of the CPU 101, the RAM 103 and the NIC 109 work together to function as the response transmission unit 409.

  In the case of real-time relay or the like, a situation in which the necessary streaming information does not exist in the buffer rarely occurs in step S521. However, in the case of other multimedia information distribution or the like, the terminal device 221 is used. If the time difference between the information provided between the terminal device 221 and the child node terminal device 221 becomes large, the streaming information may not exist in the buffer.

  In such a case, a response may not be returned to the child node, and an error indicating that “streaming information cannot be obtained even if communication with the parent node is continued” is returned to the child node. The child node may be prompted to reset the node (not shown). In these cases, the child node performs the same processing as when an error occurs due to communication of the parent node (step S516; parent).

  When the terminal device 221 of the received request (step S512; request) is not stored as a child node in the setting storage unit 401 (step S520; No), the determination unit 415 determines that the terminal device 221 of the transmission source Is determined as a child node (step S523).

  In other words, the number of child nodes already stored in the setting storage unit 401, the amount of communication in the NIC 109 of the terminal device 221 and the time waiting for some event to occur and some calculation processing are actually performed. The current communication load is estimated in consideration of the time ratio and the like, and the determination is performed based on this communication load.

  When the number of child nodes is 0, that is, when the terminal device 221 is a leaf node, it is always determined that the terminal device 221 that has transmitted the request is added as a child node. Typical.

  Note that a simple method may be adopted in which an upper limit is set for the number of child nodes that can be set, and it is determined that a child node is added up to the upper limit, and is not added after reaching the upper limit.

  Therefore, the CPU 101 functions as the determination unit 415 with reference to the status of the NIC 109, the external memory 106, the RAM 103, and the like.

  When it is determined that the terminal device 221 that has transmitted the request is not added as a child node (step S523; No), the CPU 101 selects one of the child nodes stored in the setting storage unit 401 (step S523). S524). For example, select at random, select in a cyclic order in which it became its own child node, check the communication status with each child node, select the one with the best current communication status, etc. Various aspects can be employed.

  Then, the notification transmission unit 411 transmits a notification designating the selected child node to the terminal device 221 that has transmitted the request (step S525), and returns to step S509.

  As a result, the terminal device 221 that has transmitted the request attempts to use a node that is one step down the tree structure as a parent node.

  On the other hand, when it is determined to be added as a child node (step S523; Yes), the child setting unit 408 adds the communication identifier of the terminal device 221 that has transmitted the received request as a child node in the setting storage unit 401. (Step S526).

  Therefore, the CPU 101 functions as a child setting unit 408 in cooperation with the RAM 103, the external memory 106, the HD 121, and the like. As will be described later, the child setting unit 408 also has a function of deleting the communication identifier of the child node that has become unable to communicate from the setting storage unit 401 and canceling the setting of the child node.

  In response to the request, the response transmission unit 409 obtains necessary streaming information from the buffer in the RAM 103 (step S527), and sends a response specifying the streaming information to the added child node. Transmit (step S528),

  Since the child node setting has been changed by the above processing, the selection unit 410 selects one of the current child nodes as a representative node and the other as a subordinate node (step S529).

  For the selection of the representative node, in addition to the method of selecting at random, the method of selecting the best current communication status, the method of selecting again the one selected as the representative node immediately before can be adopted. The CPU 101 functions as the selection unit 410 in cooperation with the RAM 103, the external memory 106, and the like.

  In this way, the request transmission unit 404 and the response reception unit 405 operate in order for the terminal device 221 to function as a “child node”, but the request reception unit 407, the child setting unit 408, and the response transmission unit 409 221 operates to function as a “parent node”.

  Then, the notification transmission unit 411 transmits a notification designating the parent node of the terminal device 221 to the representative node (Step S530), and transmits a notification designating the selected representative node to the subordinate node (Step S530). S531), the process returns to step S509.

  When information is exchanged by connection-type communication such as TCP / IP communication, when various types of information are transmitted, an acknowledgment indicating that the information has arrived is returned and transmitted. Therefore, if there is no such response, an error may occur due to communication with the child node.

  Further, when information is exchanged by connectionless communication such as UDP communication, there is no acknowledgment response.

  Therefore, inquiries, instructions, requests, and notifications are typically connection-type, and responses are typically sent once in connection-type, and then streaming information is exchanged in a connection-less type.

  As a result of such communication, when an error occurs due to a child node (step S516; child), the child setting unit 408 deletes the communication identifier of the child node that caused the error from the setting storage unit 401. This cancels the parent-child relationship (step S532) and returns to step S509.

  On the other hand, when an error occurs because the terminal device 221 itself is disconnected from the Internet 291 (step S516; communication disconnection), the child setting unit 408 deletes all the communication identifiers of the child nodes from the setting storage unit 401. All parent-child relationships are canceled (step S533).

  Furthermore, when one or more child nodes exist before step S533 and the representative node has been selected (step S534; Yes), the representative node is set as the parent node (step S535), and the process proceeds to step S502. Return.

  Hereinafter, for example, consider the situation of FIG. When attention is paid to node A, the children of node A are nodes P, Q, and X, and the parent of node A is node G.

  Here, if the selection unit 410 selects the node P as a representative node, G is notified to the node P, and P is notified to the nodes Q and X as alternative nodes.

  FIG. 8 is an explanatory diagram showing a state of the tree structure after a failure occurs in the node A and communication becomes impossible or the power of the node A is turned off under this situation.

  As shown in this figure, since the nodes P, Q, and X cannot communicate with their parent A, the settings are updated so that the alternative node is the parent node.

  Therefore, instead of the node A, the parent of the node P is the node G, and the children of the node P are the nodes Q and X.

  FIG. 9 is an explanatory diagram showing a state of the tree structure after the trouble of the node A is solved or the power is turned on again under this situation.

  When the node A becomes unable to communicate, the node A stores the representative node in the setting storage unit 401 as a parent node. Therefore, the parent node of node A becomes node P.

  For this reason, when communication is restored after communication with another node becomes impossible, node A tries to become a child of node P.

  Considering the number of children of the node G, the node P is arranged in the state of FIGS. 8 and 9 at the position where the node A was in the state of FIG. 2, and the number of child nodes does not increase. Therefore, the communication load of the node G is expected to be almost the same, and the communication quality can be prevented from changing greatly.

  In this situation, the node P, which is considered to have a more stable communication situation than the node A, is close to the first root node in the tree structure. Therefore, the tree structure is naturally changed so that the terminal device 221 that has been participating stably in the tree structure has a longer time and is arranged upstream.

  As described above, according to the present embodiment, the terminal device 221 autonomously determines a parent node, and even if a failure occurs in the parent node based on the notified alternative node, the entire tree structure is obtained. Streaming information can be distributed efficiently so as not to be affected.

(Instruction server device)
FIG. 10 is an explanatory diagram showing a schematic configuration of the instruction server device 241. Hereinafter, a description will be given with reference to FIG.

  The instruction server device 241 is a server device that manages the providing server device 261 and the terminal device 221 that is currently participating in the tree structure. The lobby server and the matching server in the game server prevent access concentration and distribute the load. It functions like a gateway server for planning.

  The instruction server device 241 includes a terminal storage unit 901, a server storage unit 902, an inquiry reception unit 903, an identifier extraction unit 905, an instruction transmission unit 906, and a terminal update unit 907.

  FIG. 11 is a flowchart showing a flow of control of instruction processing executed by the instruction server device 241. Hereinafter, a description will be given with reference to FIG.

  In the instruction server device 241, the inquiry reception unit 903 receives an inquiry transmitted from the terminal device 221 that is newly participating in the tree structure (step S951). Therefore, the inquiry reception unit 903 is realized by the NIC 109. The information processing apparatus 100 that implements the instruction server apparatus 241 waits until an inquiry is received. During this standby, the CPU 101 included in the information processing apparatus 100 appropriately executes other processes in a coroutine manner. It is common.

  Now, when receiving an inquiry, the identifier extraction unit 905 checks the terminal storage unit 901 and extracts a communication identifier that meets a predetermined condition (step S952).

  Here, the terminal storage unit 901 stores a pair of the communication identifier of the terminal device 221 that has transmitted the inquiry and the time when the inquiry is received. Accordingly, the terminal storage unit 901 is realized by the RAM 103, the HD 121, and the like, and the identifier extraction unit 905 is realized by the CPU 101 and the like.

  Therefore, the identifier extraction unit 905 transmits another terminal device 221 that has transmitted the inquiry from the time point that has been traced back in the past within a predetermined period from the present time, that is, the other terminal device that has recently made the inquiry. The communication identifier is extracted assuming that 221 meets a predetermined condition.

  If there is one extracted communication identifier (step S953; 1), the instruction transmission unit 906 transmits an instruction specifying the extracted communication identifier to the transmission source of the inquiry about the communication identifier (step S953; 1). S95), the process proceeds to step S959. Therefore, the instruction transmission unit 906 is realized by the NIC 109.

  On the other hand, when there are a plurality of extracted communication identifiers (step S953; plural), the CPU 101 selects one of them (step S955), and the instruction transmission unit 906 designates the selected communication identifier. Is transmitted to the transmission source of the inquiry about the communication identifier (step S956), and the process proceeds to step S959.

  For the selection in step S955, various modes such as a method of selecting one at random or a method of selecting from the oldest one can be employed.

  When the communication identifier cannot be extracted (step S953; 0), the instruction transmission unit 906 transmits an instruction specifying the communication identifier of the providing server device 261 to the transmission source of the inquiry about the communication identifier (step S953; 0). S957), the process proceeds to step S959.

  As described above, the server storage unit 902 stores the communication identifier of the providing server device 261 managed by the instruction server device 241 and is realized by the RAM 103, the HD 121, and the like.

  In addition, when a plurality of communication identifiers are stored in the server storage unit 902, the communication identifiers may be selected in a cyclic order or a random order and designated as an instruction.

  In addition, even when the communication identifier that meets the conditions cannot be extracted (step S953; 0), when the number of terminal devices 221 directly connected to the providing server device 261 exceeds a predetermined number, It is also possible to select a communication identifier of one of the terminal devices 221 at random and instruct this.

  After the instruction is transmitted, the time when the inquiry is received and the communication identifier of the inquiry transmission source are associated with each other and additionally stored in the terminal storage unit 901 to update it (step S959), and step S951. Return to.

  At the time of update, the old communication identifier, typically the communication identifier that has passed the average viewing time (or a multiple of the constant) from the transmission of the inquiry is deleted from the terminal storage unit 901. It is also good.

  Note that a mode in which a plurality of communication identifiers are designated in the instruction can also be adopted. In this case, a predetermined number of communication identifiers are extracted sequentially from the latest to the past (old), and the order is randomly shuffled and specified in the instruction.

  The terminal device 221 that has received the instruction tries to determine whether each of the communication identifiers specified in the instruction can be a parent node. If communication with any of the communication identifiers is possible, the terminal device 221 is used as a parent node. The instruction server device 241 may be inquired again.

  In addition, the terminal update unit 907 of the instruction server device 241 also stores in the terminal storage unit 901 information on which communication identifier has been designated and returned in response to the inquiry. When an inquiry is made again within the period, it is possible to preferentially extract those that do not overlap with the instructed communication identifier.

  Now, in general, in the case of streaming distribution, a user who has started viewing the same content at the same time completes viewing at the same time.

  Therefore, there is a high possibility that the period in which the terminal device 221 that has made an inquiry at the same time is active is overlapped as compared to the period in which the terminal device 221 that has made an inquiry at another time is active. By adopting the above aspect, there is a high possibility that the terminal device 221 that has made an inquiry within a certain period of time is arranged relatively close in the tree structure.

  Further, if the period to be referred to when extracting is an average usage time, the possibility of instructing a terminal device 221 that exceeds this time becomes low, and therefore, there is a possibility of instructing a terminal device 221 that cannot communicate Decrease.

  Further, when it is congested, an instruction is given to the other terminal device 221 as the parent node, and when it is not congested, an instruction is given to the providing server device 261 as the parent node. Therefore, the data distribution policy is dynamically changed according to the degree of congestion.

  Furthermore, since it is not necessary to inquire from the instruction server device 241 whether or not the terminal device 221 is still operating, traffic in the network can be suppressed and prompt instructions can be made.

  For this reason, it is expected that the communication efficiency in the whole tree structure is improved.

(Providing server device)
FIG. 12 is an explanatory diagram showing a schematic configuration of the providing server device 261. Hereinafter, a description will be given with reference to FIG.

  The providing server device 261 includes a request reception unit 931, an information storage unit 932, and a response transmission unit 933.

  Here, the request receiving unit 931 and the response transmitting unit 933 in the providing server device 261 perform the same functions as the request receiving unit 407 and the response transmitting unit 409 in the terminal device 221, and the information storage unit 932 in the providing server device 261 is a terminal. It performs the same function as the buffer in device 221.

  FIG. 13 is a flowchart showing a flow of control of the providing process executed by the providing server device 261. Hereinafter, a description will be given with reference to FIG.

  In the providing server device 261, the request receiving unit 931 receives the request transmitted from the terminal device 221 (step S971). Therefore, the request receiving unit 931 is realized by the NIC 109. The information processing apparatus 100 that implements the providing server apparatus 261 waits until a request is received. During this standby, the CPU 101 included in the information processing apparatus 100 appropriately executes other processes in a coroutine manner. It is common.

  When the request is received, in response to the request, the CPU 101 acquires necessary streaming information from the information storage unit 932 (step S972). Unlike the buffer of the terminal device 221, the providing server device 261 holds all streaming information to be provided in the information storage unit 932. Therefore, there is no case where streaming information cannot be acquired. Typically, the information storage unit 932 is realized by the HD 121 or the like.

  Further, the response transmission unit 933 transmits a response designating the acquired streaming information to the terminal device 221 that is the transmission source of the request (step S973), and returns to step S971. Therefore, the response transmission unit 933 is realized by the NIC 109.

  As described above, the providing server device 261 adopts the same configuration as that of a general streaming server. In the present embodiment, the provision server device 261 is configured to devise the processing after the streaming delivery from the providing server device 261. Therefore, communication efficiency is improved.

  As described above, according to the present invention, a terminal device, a communication system, a terminal method, and a terminal device that are suitable for efficiently performing reorganization of a tree structure when communication fails when communicating as a tree-structured node. In addition, it is possible to provide a program that realizes these on a computer.

100 Information processing apparatus 101 CPU
102 ROM
103 RAM
104 Interface 105 Controller 106 External Memory 107 Image Processing Unit 108 DVD-ROM Drive 109 NIC
110 Audio processing unit 111 Microphone 121 HD
201 communication system 221 terminal device 241 instruction server device 261 providing server device 291 Internet 401 setting storage unit 402 inquiry transmission unit 403 instruction reception unit 404 request transmission unit 405 response reception unit 406 provision unit 407 request reception unit 408 child setting unit 409 response transmission Unit 410 selection unit 411 notification transmission unit 412 notification reception unit 413 parent setting unit 415 determination unit 416 introduction transmission unit 417 introduction reception unit 901 terminal storage unit 902 server storage unit 903 inquiry reception unit 905 identifier extraction unit 906 instruction transmission unit 907 terminal update Unit 931 Request reception unit 932 Information storage unit 933 Response transmission unit

Claims (5)

A communication system using a tree structure in which a providing server device is a root node and a terminal device is an intermediate node and a leaf node, the communication system includes an instruction server device,
(A) The terminal device
A request transmission unit for transmitting a request for providing information to a parent node of the terminal device;
A response receiver for receiving a response specifying the provision information transmitted from the parent node of the terminal device;
A providing unit that allows a user to view the provided information specified in the received response;
A request receiving unit for receiving a request for provision information transmitted from another terminal device;
When the request is received from a terminal device that is not set as a child node of the terminal device, a new child node is set based on the number of child nodes already set in the terminal device or the communication amount of the terminal device. A determination unit for determining whether or not
A child setting unit that sets a terminal device that is a transmission source of the received request as a child node of the terminal device, when the determination unit determines to set a new child node;
A response transmission unit that is a child node of the terminal device and transmits a response designating the provision information to the terminal device that is the transmission source of the received request;
If the determination unit determines not to set a new child node, an introduction transmission unit that transmits an introduction designating one of the child nodes of the terminal device to the terminal device that is the transmission source of the request;
An introduction receiving unit for receiving an introduction transmitted from the terminal device to which the request is transmitted;
A selection unit that selects any of the child nodes of the terminal device as a representative node and selects other child nodes as subordinate nodes,
A notification specifying that the parent node of the terminal device should be an alternative node is sent to the selected representative node, and the selected representative node should be an alternative node to the selected subordinate node A notification sending unit that sends a notification specifying
A notification receiving unit for receiving a notification transmitted from a parent node of the terminal device;
When the introduction is received by the introduction receiving unit, the terminal device designated in the introduction is set as a parent node, and when communication with the parent node of the terminal device fails, the alternative designated in the received notification A parent setting section for setting a node as a new parent node ;
An inquiry transmission unit that transmits an inquiry for an instruction to the instruction server device when communication with a parent node that was an alternative node fails
With
When the setting of the child node of the terminal device is changed, the selection unit performs the selection again,
(B) The instruction server device
An inquiry receiving unit for receiving an inquiry transmitted from the terminal device;
When the inquiry is received, an extraction unit that selects either the providing server device or the terminal device that has already given an instruction,
An instruction transmitting unit that transmits an instruction to specify the selected communication device to the terminal device that is the transmission source of the received inquiry;
A terminal storage unit in which the identifier of the terminal device to which the instruction is transmitted is associated with the time when the inquiry from the terminal device is received, and is stored only for the average viewing time of the provided information
With
If the identifier is stored in the terminal storage unit, the extraction unit extracts a predetermined number of times corresponding to the identifier from the latest to the past, and the terminal device having the extracted identifier If the identifier is not stored in the terminal storage unit, select the providing server device,
(C) The terminal device
An instruction receiving unit that receives an instruction transmitted from the instruction server device
Further comprising
When the instruction is received, the parent setting unit sets a communication device that can communicate among the communication devices specified in the received instruction as a parent node,
(D) The providing server device
A request receiving unit for receiving a request for providing information from the terminal device;
When the request is received, a response transmission unit that transmits a response designating provision information to the terminal device that is the transmission source of the received request
Communication system comprising: a. The communication system according to claim 1 ,
When a plurality of terminal devices are selected by the extraction unit, the instruction transmission unit specifies the instruction after shuffling the selected terminal device,
When the instruction is received, the parent setting unit sequentially attempts communication with the communication device specified in the received instruction, and sets the communication device that has succeeded in communication as a parent node. Communications system. The communication system according to claim 1 or 2 ,
In the terminal device, when the communication with the child node of the terminal device fails, the child setting unit cancels the setting of the child node in which the communication has failed . The communication system according to any one of claims 1 to 3 ,
Communication between the terminal devices is performed via a computer communication network,
When re-established after communication with the computer communication network is disabled, the child setting unit cancels all of the child node settings that have already been set, and the parent setting unit selects the selected A communication system characterized by setting a representative node as a new parent node . A communication method executed by a communication system using a tree structure with a providing server device as a root node and a terminal device as an intermediate node and a leaf node, the communication system having an instruction server device,
The terminal device includes a request transmission unit, a response reception unit, a provision unit, a request reception unit, a determination unit, a child setting unit, a response transmission unit, an introduction transmission unit, an introduction reception unit, a selection unit, a notification transmission unit, a notification reception unit, It has a parent setting part , inquiry sending part, instruction receiving part,
The instruction server device includes an inquiry reception unit, an extraction unit, an instruction transmission unit, a terminal storage unit,
The providing server device includes a request receiving unit and a response transmitting unit,
(A) In the terminal device,
A request transmission step in which the request transmission unit transmits a request for providing information to a parent node of the terminal device;
A response receiving step in which the response receiving unit receives a response designating provision information transmitted from a parent node of the terminal device;
A providing step in which the providing unit causes a user to view provided information specified in the received response;
A request receiving step in which the request receiving unit receives a request for providing information transmitted from another terminal device;
When the request is received from a terminal device that is not set as a child node of the terminal device, the determination unit newly determines based on the number of child nodes already set in the terminal device or the communication amount of the terminal device. A determination step for determining whether or not to set a child node,
In the determination step, when it is determined to set a new child node, the child setting unit sets the terminal device that is the transmission source of the received request as a child node of the terminal device. ,
A response transmission step in which the response transmission unit is a child node of the terminal device and transmits a response designating the provision information to the terminal device that is the transmission source of the received request;
When the determination unit determines not to set a new child node, the introduction transmission unit transmits an introduction designating one of the child nodes of the terminal device to the terminal device that is the transmission source of the request. Referral transmission process,
An introduction receiving step in which the introduction receiving unit receives an introduction transmitted from a terminal device to which the request is transmitted;
A selection step in which the selection unit selects one of the child nodes of the terminal device as a representative node and selects another child node as a subordinate node;
The notification transmission unit transmits a notification designating that the parent node of the terminal device should be an alternative node to the selected representative node, and sends the selected representative node to the selected subordinate node. A notification transmission step of transmitting a notification designating that it should be an alternative node;
A notification receiving step in which the notification receiving unit receives a notification transmitted from a parent node of the terminal device;
When an introduction is received by the introduction receiving unit, the parent setting unit sets the terminal device designated for the introduction as a parent node, and when communication with the parent node of the terminal device fails, the parent setting unit but parent setting step the specified alternate node, sets a new parent node to the received notification,
An inquiry transmission unit that transmits an inquiry for an instruction to the instruction server device when communication with a parent node that was an alternative node fails
With
When the setting of the child node of the terminal device is changed, the selection unit performs the selection again,
(B) In the instruction server device,
The inquiry reception unit receives an inquiry transmitted from the terminal device,
When the inquiry is received, the extraction unit selects either the providing server device or the terminal device that has already given an instruction,
An instruction transmission step in which the instruction transmission unit transmits an instruction to specify the selected communication device to the terminal device that is the transmission source of the received inquiry;
A terminal storage step of storing, in the terminal storage unit, the identifier of the terminal device to which the instruction is transmitted in association with the time when the inquiry from the terminal device is received, for the average viewing time of the provided information
With
In the extraction step, if an identifier is stored in the terminal storage unit, the time associated with the identifier is extracted from the latest one to the past, and a terminal device having the extracted identifier If the identifier is not stored in the terminal storage unit, select the providing server device,
(C) In the terminal device,
An instruction receiving step in which the instruction receiving unit receives an instruction transmitted from the instruction server device
Further comprising
In the parent setting step, when the instruction is received, among communication devices specified in the received instruction, a communication device capable of communication is set as a parent node,
(D) In the providing server device,
A request receiving step in which the request receiving unit receives a request for providing information from the terminal device;
When the request is received, the response transmission unit includes a response transmission step of transmitting a response designating provision information to a terminal device that is a transmission source of the received request .

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