JP2009065572A - Communications apparatus, its control method, communication system, data transmission system, communications apparatus control program, and recording medium with the program stored - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To transmit content at a high speed and with appropriate quality, by rapidly setting a band. <P>SOLUTION: STB 17 is connected to a network and receives the content from a VoD server 12 via one or more networks that include the network. The STB 17 includes a relating information acquiring part 41 for acquiring content relating information, including a bit rate indicative of a band required for transmitting the content, with respect to a plurality of pieces of content; a related information storage part 46 for storing the related information acquired by the related information acquiring part 41; a selection instruction acquiring part 42 for selecting content to be received from the plurality of pieces of content; and a band-setting request part 43 for requesting a PLC master unit 15 for data transmission management in the network, to read the bit rate of the related information of the content, selected by the selection instruction acquiring part 42 from the related information storage part 46 so as to set a band indicated by the read bit rate. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a communication device that is connected to a network and receives data from a server via one or more networks including the network, a control method thereof, a communication system, a data transmission system, a communication device control program, and the program. The present invention relates to a recorded recording medium. Specifically, the present invention relates to a communication device that receives content transmitted from a server.

  Stream content such as video and audio provided from content providing devices such as content servers outside the home via an access network such as the Next Generation Network (NGN) network on a home TV or STB (Set Top Box) The service to receive is performed. When data from the access network is transmitted to the home, the data is once received by a gateway (router) and transferred to a content receiving terminal (television or STB) through a network constructed in the home. In general, Ethernet (registered trademark) is used for the connection between the router and the receiving terminal. However, when the router and the receiving terminal are installed in different rooms, the Ethernet (registered trademark) is used. ) Cables need to be laid.

  On the other hand, power line carrier communication (PLC) is a technique for performing data transmission through a power line, and communication between ordinary outlets is possible without requiring special construction. If a bridge device (PLC adapter) between the PLC and Ethernet (registered trademark) is connected to the router and the receiving terminal via Ethernet (registered trademark), the PLC can be used even when the router and the receiving terminal are arranged apart from each other. The router and the receiving terminal can communicate with each other via an adapter, and a home network can be constructed without installing a new cable. A similar home network can also be constructed using a bridge device between a wireless LAN and Ethernet (registered trademark).

In such a system, in order for the receiving terminal to receive stream data that requires content, particularly immediacy (real-time performance) and continuity such as moving images and audio, from a content providing apparatus at high speed and high quality, In each network, necessary and sufficient bandwidth must be ensured according to the content.
<QoS technology>
By the way, in transmission of non-real-time data such as Web contents, mail, and FTP, even if a certain amount of transmission delay or jitter (transmission delay fluctuation) occurs, it does not become a big problem for the user. On the other hand, in transmission of real-time data such as video and audio, transmission delay and jitter lead to disturbance of video and audio, and thus must be within a certain range.

A technique for simultaneously and efficiently realizing a plurality of data transmissions while ensuring appropriate quality according to the type of data transmitted in this way is called a QoS (Quality of Service) technique. QoS techniques are roughly classified into priority control type QoS (Prioritized QoS) and parameter guaranteed type QoS (Parameterized QoS).
<Priority control type QoS>
In priority control type QoS, a communication device that transmits data gives priority to the data packet according to the type of data and the nature of the communication device that transmits and receives data, and prioritizes transmission according to the priority assigned to the packet. This is a method for realizing QoS by controlling.

  Generally, a field for storing priority is provided in the header portion of the packet, and the priority is stored as a numerical value therein.

For example, since real-time data requires higher transmission quality than non-real-time data, the priority field of the header of real-time data is a numerical value indicating a higher priority than the priority field of the header of non-real-time data. Is stored and transmitted with a priority according to the numerical value, thereby realizing QoS.
<Parameter guaranteed QoS>
The parameter guarantee type QoS provides a master station that manages the bandwidth of the entire network, and the master station manages the use schedule of the bandwidth in the entire network according to the QoS parameters notified from the slave station, and the number of transmissions of all slave stations This is a method for realizing QoS by centrally managing transmission times.

  When a QoS guarantee is required for data to be transmitted or received, the slave station transmits a QoS transmission request signal to the master station in advance. The request signal includes a QoS parameter, and the master station interprets the QoS parameter and determines whether QoS can be realized from the current network usage status. If feasible, QoS transmission is permitted, and if not feasible, it is rejected.

  For example, when another child station has already performed QoS transmission and a sufficient band does not remain, the parent station rejects QoS transmission.

  The master station always manages the bandwidth allocation schedule so that the QoS for each slave station is guaranteed, and transmits a transmission permission signal to each slave station according to the schedule. The slave station transmits data only during the period notified by the transmission permission signal.

  With such a mechanism, there is no access contention in the entire network, and QoS is realized.

  In the parameter guaranteed QoS, QoS is managed for each flow. A flow refers to a series of data that needs to be transmitted continuously, such as one video content or audio content, and a plurality of packets belong to this series of data.

  When transmitting a plurality of contents at the same time, it is necessary to perform different QoS control for each content. For example, when one communication apparatus transmits video content and audio content at the same time, QoS requirements required for each content are different.

  Since the master station needs to determine a bandwidth use schedule for each flow during data transmission, it is necessary to know the flow to which the packet belongs and the required QoS parameters when transmitting the packet. is there.

  In order to realize QoS for each flow, the slave station notifies the master station with the flow identification information when reporting the QoS parameter. The master station manages a bandwidth allocation schedule for each flow, and when transmitting a transmission permission signal, notifies the master station including the flow identification information in order to indicate which flow is permitted to be transmitted. The communication device that performs transmission can perform QoS control for each flow by transmitting only packets that match the notified flow identification information in the notified period.

  By the way, in a system that receives content such as video and audio provided from a content providing device such as an off-site content server as described above via an access network such as an NGN network, the content providing device outside the home In response to a request from the user, first, the content list, an electronic content guide (ECG), and the like are informed of the content that can be provided, and based on the content, the content designated to receive the viewing request of the content selected by the user The method of distributing the video is often used in VoD (video on demand). Alternatively, the content providing apparatus informs the contents of content that can be provided by an electronic program guide (EPG) or the like, and a method called multicast for distributing the same stream data to a plurality of recipients is taken by IP broadcasting or the like.

  Here, a content providing device such as a server cannot know the usage status or allocation status of a bandwidth in a home network built by power line carrier communication or the like ahead of the user's home gateway, and ensuring QoS in the home network is not possible. In fact, regardless of the priority control type QoS and the parameter guarantee type QoS, it must be left to the user (or an apparatus constituting the home network).

  Therefore, when content is received at the gateway via the access network and transferred to the home network as in the above system, QoS is ensured also in the home network in order to receive the distributed content without disturbance. It is necessary for the user to secure the QoS of the home network necessary for content reception.

In such a case, conventionally, the user selects the desired content from the content held by the server and notifies the server, and the server transmits the bandwidth information necessary for receiving the selected content to the receiving terminal, The receiving terminal sets a band based on the received band information (Patent Document 1 and Patent Document 2).
Patent No. 3464788 (issued on November 10, 2003) JP 2004-274700 A (published September 30, 2004)

  However, the bandwidth setting methods of Patent Documents 1 and 2 described above are not the only when the user selects content and notifies the server of the bandwidth information corresponding to the selected content from the server to the wireless terminal (on the user side). This is a mechanism for transmission to a communication device). In other words, each time a content is selected, the wireless terminal makes an inquiry to the server, acquires bandwidth information corresponding to the content, and requests bandwidth setting from the base station that manages the bandwidth based on the acquired bandwidth information. Is. For this reason, there has been a problem that it takes time to set the bandwidth. As a result, it takes time for the user to view the desired content.

  Therefore, in view of such circumstances, an object of the present invention is to provide a communication device that can quickly set a band and can quickly receive desired data with appropriate quality.

A communication apparatus according to the present invention is a communication apparatus connected to a network and receiving data from a server via one or more networks including the network,
Related information acquisition means for acquiring related information related to the data, the related information including at least band information indicating a band necessary for transmitting the data, with respect to the plurality of data, and the related information acquisition means A storage unit that stores the related information acquired by the data, a data selection unit that selects data to be received from the plurality of data, and band information included in the related information related to the data selected by the data selection unit from the storage unit. Bandwidth setting requesting means for requesting the management apparatus that manages data transmission in the network so as to perform band setting based on the read band information and the read band information is provided.

  The communication device control method according to the present invention is a communication device control method that is connected to a network and receives data from a server via one or more networks including the network, and is related to the data. A related information acquisition step of acquiring related information relating to a plurality of the data, the related information including at least band information indicating a band necessary for transmitting the data, and storing the acquired related information in a storage unit; A data selection step for selecting data to be received from the plurality of data, and band information included in the related information relating to the data selected in the data selection step is read from the storage unit, and based on the read band information The bandwidth setting required to the management device that manages the transmission of data in the network so as to set the bandwidth. It is characterized by comprising a request step.

  According to the configuration and method described above, first, related information related to data received from the server is acquired with respect to the plurality of data and stored in the storage unit. Then, when the data to be received is selected, the bandwidth information included in the related information regarding the selected data is read from the storage unit, and the data transmission in the network is performed so as to perform the bandwidth setting based on the read bandwidth information. Request to the management device that manages As a result, a bandwidth necessary for transmitting the selected data on the network can be ensured, so that the communication apparatus can receive the selected data with appropriate quality.

  Furthermore, since the related information related to each of the plurality of data is stored in the storage unit, when newly selecting data to be received, the related information corresponding to the data may be read from the storage unit, There is no need to obtain new related information from outside. Accordingly, it is possible to promptly request to perform bandwidth setting based on the bandwidth information included in the related information read from the storage unit, and it is possible to quickly receive desired data with appropriate quality.

  The related information may be acquired from a server or may be acquired from another device. Further, it may be acquired upon request, or may be acquired from information broadcast periodically, such as an electronic program guide. Further, the server requesting the related information may be the same as or different from the server requesting the data.

  In the communication apparatus according to the present invention, the related information includes identification information for identifying the data and the band information, and the data selection unit includes at least identification information of the related information stored in the storage unit. It is preferable to include a presenting means for presenting the user to the user and a receiving means for accepting selection of the identification information by the user as the data to be received. In this case, the user can select the data desired to be received from the server by referring to the identification information of the presented data and selecting it.

  In the communication device according to the present invention, the presenting means can obtain at least identification information of the related information in a state where it is possible to determine whether or not the related information related to the data includes bandwidth information. It is preferable to present it to the user. Accordingly, it is possible for the user to avoid selecting content that causes video or audio disturbance unintentionally, thereby improving convenience.

  In the communication apparatus according to the present invention, it is preferable that the presenting means presents the identification information only for data in which band information is included in the related information. Accordingly, it is possible for the user to avoid selecting content that causes video or audio disturbance unintentionally, thereby improving convenience.

  The communication apparatus according to the present invention may further comprise data transmission requesting means for requesting the server to transmit the data when a notification that the band requested by the band setting requesting means has been set is obtained from the management apparatus. preferable. In this case, since the data is received from the server after the requested bandwidth is secured, the selected data can be reliably received with appropriate quality.

  In the communication apparatus according to the present invention, the related information includes required time information indicating the time required to transmit the data and the band information, and the related information on the data selected by the data selecting means. The required time information is read from the storage unit, and when the required time indicated by the read required time information has elapsed from the start of reception of the data, the band set by the request of the band setting request unit is released so as to release the band It is preferable to further include bandwidth release request means for requesting the management device.

  In this case, when the required time elapses from the start of data reception, the band is released. Therefore, even when the transmission completion notification indicating that the server has completed the transmission of the data is not transmitted from the server to the communication device due to some trouble, the bandwidth is released if the required time has elapsed. Can be avoided.

  In the communication apparatus according to the present invention, the related information acquisition unit may request a condition of data to be received from a server that provides the related information, and acquire related information that matches the condition. In this case, only the relevant information that matches the condition of the data to be received can be acquired from the relevant information of all the data that can be provided by the server, so that the use of resources such as the network and the storage unit can be reduced. The above conditions can be set at various timings.

  In addition, if the communication system includes a network, a management device that is connected to the network and manages transmission of data in the network, and a communication device configured as described above that is connected to the network, the same effect as described above There is an effect.

  The network is assumed to be a local area network in a building because a communication device used by a general user is connected. An example of such a network is a power line carrier communication network. In the case of a power line carrier communication network, a power line laid in a building can be used as a communication medium, so that it is not necessary to lay a new network cable in the building.

  If the data transmission system includes a communication system configured as described above and a server that is connected to the communication system via a network different from the network of the communication system and transmits data to the communication device, The effect similar to an effect can be show | played.

  Further, the server transmits related information on data that matches a predetermined condition corresponding to the communication device or related information on data that matches a condition requested by the communication device to the communication device. May be. In this case, only the relevant information that matches the predetermined condition is transmitted among the relevant information of all the data that can be provided by the server, so that the use of communication resources and resources of the communication device can be reduced. Different conditions can be set for each communication device. The above conditions can be set at various timings.

  Each unit of the communication device can be executed on a computer by a communication device control program. Further, by storing the communication device control program in a computer-readable recording medium, the communication device control program can be executed on an arbitrary computer.

  As described above, the communication device according to the present invention acquires related information related to each of a plurality of data and stores it in the storage unit before selecting the data, so when newly selecting data to be received, The related information of the data can be acquired by simply reading the related information corresponding to the data from the storage unit. Therefore, when setting a band for receiving data, it is possible to request a band setting based on the band information included in the related information read from the storage unit without inquiring the data management source for the band information each time data is selected. Therefore, there is an effect that it can be requested promptly and desired data can be received promptly with appropriate quality.

  An embodiment of the present invention will be described below with reference to FIGS.

  FIG. 1 is a block diagram showing a basic configuration example of a communication system to which the present invention is applied. As illustrated, the communication system 1 includes a server 2, a first network 3, a network relay device 4, a network management device (management device) 5, a second network 6, and a communication device 7. The server 2 is connected to the network relay device 4 through the first network 3, and the communication device 7 is connected to the network relay device 4 through the second network 6. Further, a network management device 5 is connected to the second network 6.

  With this connection, the server 2 and the communication device 7 transmit and receive data via a plurality of networks 3 and 6 (network group) connected via the network relay device 4. Further, the network management device 5 manages communication in the second network 6 such as setting a communication band between devices in the second network 6.

  In the present embodiment, the server 2 and the communication device 7 communicate with each other via the two networks of the first network 3 and the second network 6. The apparatus 7 may communicate with one or more arbitrary numbers of networks.

[Embodiment 1]
Next, a more specific configuration of the communication system 1 shown in FIG. 1 will be described with reference to FIG. FIG. 2 is a schematic diagram showing a configuration of a content distribution system (data transmission system) 11 to which the present invention is applied. 2, it can be easily understood how the simplified basic configuration of FIG. 1 is actually configured. However, the configuration of the system in FIG. 2 is an example, and various other configurations are possible.

  In FIG. 2, the server 2 corresponds to a VoD (video on demand) server 12, the first network 3 corresponds to the NGN network 13, the network relay device 4 corresponds to the home gateway 14, and the communication device 7 corresponds to the set top. Corresponding to the box 17, the network management device 5 corresponds to a PLC (Power Line Communication) base unit 15, and the second network 6 corresponds to a PLC network 16 that performs communication via a power line. Hereinafter, the home gateway is represented as “HGW”. Instead of the NGN network 13, another access network may be used. For example, ADSL (Asymmetric Digital Subscriber Line) or FTTH (Fiber to the Home) may be used.

  Furthermore, a PLC adapter 18 is provided between the PLC network 16 and various devices. The PLC adapter 18 is a device that mutually converts an Ethernet (registered trademark) signal and a PLC signal. The HGW 14, the STB 17, and the other device 19 have a terminal for Ethernet (registered trademark), and are connected to the PLC adapter 18 with an Ethernet (registered trademark) cable, thereby allowing the PLC adapter 18 and the PLC network 16 to pass through. Can communicate with each other. In the following, when each of the HGW 14 and the PLC adapter 18 connected to the STB 17 is particularly shown, 18a, 18b, and 18c are used as symbols as shown in FIG.

  In addition, a TV (television) receiver (hereinafter referred to as “TV”) 20 is connected to the STB 17 as an example of a display device that displays various data such as video content. Note that the function of the STB 17 may be built in the TV 20, and the TV 20 and the PLC adapter 18 may be connected by Ethernet (registered trademark).

  In the example of FIG. 2, the HGW 14, the PLC master device 15, the STB 17, and the device 19 are each connected to the PLC network 16 via an external PLC adapter 18, but each has a built-in PLC adapter 18. May be.

  In FIG. 2, the PLC adapter 18 b is illustrated as externally connected to the PLC master unit 15, but the PLC adapter 18 b actually includes the function of the PLC master unit 15. The function of the PLC master unit 15 is included not only in the PLC adapter 18 b but also in all other PLC adapters 18, and one of the plurality of PLC adapters 18 according to the communication status of the PLC network 16. Functions as the PLC master unit 15. However, in the following embodiment, in order to facilitate understanding of the present invention, it is assumed that the PLC master unit 15 independent of the PLC adapter 18 is connected to a specific PLC adapter 18b.

  Next, details of the content distribution system 11 configured as described above will be described. First, the VoD server 12 distributes stored video content based on a request from a user. The VoD server 12 stores video content data to be provided to the user and related information data such as bit rate, required transmission time, and offer price associated with the video content in a storage unit (not shown). Yes.

  Further, when the STB 17 obtains from the user that the user desires to view a certain video content via a remote controller, an operation button (not shown) or the like, the STB 17 requests transmission of the video content. Is transmitted to the VoD server 12 via the PLC network 16 and the NGN network 13. The VoD server 12 transmits video content corresponding to the received transmission request to the STB 17 in a packet form. Then, the STB 17 reconstructs the video content packet received from the VoD server 12 as video content, and presents it to the user as video on the TV 20.

  As described above, in the present embodiment and the embodiments described later, video content is used as a specific example of data received by a communication device used by a user. Hereinafter, the video content is simply referred to as “content”. Examples of the data include various data such as still image data, audio data, text data, and Web content data.

  By the way, when the VoD server 12 transmits content to the STB 17, if the transmission bandwidth of the networks 13 and 16 on the transmission path is not secured for the content transmission, the network 13 and 16 on the transmission path A packet loss or a packet transmission delay occurs, resulting in an adverse effect such that, for example, the finally presented video is disturbed.

  In the form as shown in FIG. 2, the VoD server 12 manages the transmission band in the network of the NGN network 13 to which the VoD server 12 is directly connected. However, the VoD server 12 is not directly connected to the network. In general, it is not possible to know whether a sufficient transmission band is ensured in order to perform content transmission without delay in a network (PLC network 16 in this embodiment) beyond HGW 14, which is 4.

  Therefore, with respect to the PLC network 16, the PLC master unit 15 secures a transmission band necessary for the transmission of the content in response to a request from the STB 17, which is a user side device.

  FIG. 3 shows a main configuration of the STB 17 in the content distribution system 11. As illustrated, the STB 17 includes a control unit 31, a storage unit 32, a communication unit 33, an input unit 34, an output unit 35, and a timer 36. FIG. 3 shows only the configuration related to the present invention, but the actual STB 17 includes other configurations.

  The control unit 31 comprehensively controls various components in the STB 17. The function of the control part 31 is implement | achieved when CPU runs the program memorize | stored in memory elements, such as RAM and flash memory, for example. Details of the control unit 31 will be described later.

  The storage unit 32 includes a storage device such as a RAM or a hard disk drive (HDD), and stores various data and programs. Note that details of data stored in the storage unit 32 in the present embodiment will be described later.

  The communication unit 33 is for performing data communication with various devices such as the VoD server 12 and the PLC master unit 15 via the PLC network 16.

  The input unit 34 is for inputting various information from the user. Examples of the input unit 34 include an operation input device such as an operation button and a keyboard, an image input device such as a camera, and a reception device that receives a signal from a remote controller. The input unit 34 converts the input information into a predetermined data format and transmits it to the control unit 31.

  The output unit 35 is for outputting various information received from the control unit 31 to the outside. Examples of the output unit 35 include a display device such as an LCD (Liquid Crystal Display), an audio output device such as a speaker, and a printing device that performs printing on paper. In the present embodiment, the output unit 35 includes: It includes a transmission device that converts data received from the control unit 31 into a format suitable for transmission to the TV 20 and transmits the data to the TV.

  The timer 36 is for measuring time. Specifically, the timer 36 starts timing based on an instruction from the control unit 31 and notifies the control unit 31 when the time specified by the control unit 31 is reached.

  Next, details of the control unit 31 and the storage unit 32 will be described. As shown in FIG. 3, the control unit 31 includes a related information acquisition unit (related information acquisition unit, data selection unit, presentation unit) 41, a selection instruction acquisition unit (data selection unit, reception unit) 42, a bandwidth setting request unit ( A band setting request unit) 43, a content acquisition unit (data transmission request unit) 44, and a band release request unit (band release request unit) 45. In addition, the storage unit 32 includes a related information storage unit 46 that stores related information of content.

  The related information acquisition unit 41 requests the VoD server 12 to provide the related information of the content via the communication unit 33 or the like prior to the acquisition of the content based on the instruction acquired from the user via the input unit 34. Among the contents provided by the VoD server 12, the related information of all the contents that can be reproduced in the current apparatus is collectively acquired via the communication unit 33 or the like. The related information acquisition unit 41 stores the acquired related information in the related information storage unit 46. Further, the related information acquisition unit 41 transmits part or all of the acquired related information to the TV 20 via the output unit 35. Thereby, the related information is displayed on the TV 20.

  FIG. 4 shows an example of content related information stored in the related information storage unit 46. In the example shown in the drawing, the related information includes a title name that is information for identifying content, a bit rate that is information on the transmission band of the content, and a required time indicating the time required for content transmission for each content. It is associated. For example, the content whose title is “ABC” indicates that the bit rate required for transmission is 10 Mbps and the time required for transmission is one hour.

  Information provided as content-related information from the VoD server 12 needs to include at least a title name and a bit rate in order to implement the present invention, but when the user selects content, Other information may be included to increase convenience. For example, the genre of the content, the name of the actor who appears, and a commentary on the content can be considered.

  When there are a large number of contents that can be viewed by the user, it may be possible to provide related information of some contents without providing related information of all contents at once. In this case, when the content related information request is received again from the STB 17, all or a part of the remaining content related information may be provided. For example, assuming that there are 100 contents that can be viewed, the related information of 10 contents among them is provided first, and the user performs some operation and receives the request for the related information of the contents from the STB 17 again. Sometimes the following 10 content related information is provided.

  In the example of FIG. 4, the title name is used as information for identifying the content. However, any information can be used as long as the content can be uniquely identified, such as an ID number. When content is identified by title name, there is a possibility that content with the same title name may exist. Therefore, it is desirable to assign an ID that can uniquely identify the content on the VoD server 12 side, but the explanation is simple. Therefore, in the following, it is assumed that the content can be uniquely identified only by the title name. Further, in order to increase convenience when selecting the content as described above, other additional information may be stored in the related information storage unit 46 in association with the title name.

  In addition, the related information acquisition unit 41 does not request and acquire the related information for each instruction from the user, but requests it every predetermined period, every predetermined time, or when the STB 17 is turned on. You may get it. In addition, when content distribution is performed not from the VoD server 12 but from an IP broadcast server, an electronic program guide (EPG) provided by the IP broadcast server is related to content related information, although the format is different from FIG. The information acquisition part 41 can utilize. An embodiment using an electronic program guide (EPG) will be described later.

  Further, when the user selects content, the related information acquisition unit 41 preferably transmits at least the title name of the related information to the TV 20 for display. In this case, the user can easily specify the content from the title name displayed on the TV 20.

  When displaying the title name on the TV 20, it is preferable to present the content in which the related information includes the bit rate and the content that does not include the bit rate in a state where the user can distinguish them. If the bit rate cannot be obtained, bandwidth is not secured, and video and audio may be disturbed when data is received. For the user, if such a possible content can be discriminated in advance, it is possible to avoid selecting a content that causes video or audio disturbance unintentionally, thereby improving convenience. As a method for distinguishing the content, for example, the title name of the content or the color of the background portion thereof is changed, or the band information is included in the vicinity of the title name and / or the band information is included. It may be possible to display an icon indicating that it is not. When content that does not include bandwidth information is selected, a message indicating that may be displayed on the screen to warn the user. Furthermore, it is conceivable that the content name that does not include the band information is not displayed in the first place so that the user cannot select it. When the related information is stored in a server different from the server that provides the content itself, the related information acquisition unit 41 may acquire the related information by requesting the related information from the other server.

  Returning to FIG. 3, the selection instruction acquisition unit 42 acquires an instruction to select content that the user desires to view from the user via the input unit 34. The selection instruction acquisition unit 42 reads the related information of the content corresponding to the acquired selection instruction from the related information storage unit 46 and transmits it to the band setting request unit 43 and the content acquisition unit 44. The selection instruction acquisition unit 42 may transmit only the bit rate of the related information to the band setting request unit 43, or may transmit only the title name and the required time of the related information to the content acquisition unit 44. Good.

  The band setting request unit 43 transmits a band setting request for requesting to set a transmission band corresponding to the bit rate of the related information received from the selection instruction acquiring unit 42 to the PLC master unit 15 via the communication unit 33 or the like. To do. When the bandwidth setting request unit 43 receives a setting completion notification indicating that the setting of the transmission band has been completed by the PLC base unit 15 from the PLC base unit 15 via the communication unit 33 or the like, the bandwidth setting request unit 43 sends the received setting completion notification to the content The data is transmitted to the acquisition unit 44.

  The content acquisition unit 44 acquires content corresponding to the title name of the related information received from the selection instruction acquisition unit 42 from the VoD server 12 via the communication unit 33 or the like. Specifically, when the content acquisition unit 44 receives the setting completion notification from the band setting request unit 43, the content acquisition unit 44 sends a content transmission request for transmitting the content corresponding to the title name via the communication unit 33 or the like. By transmitting to the VoD server 12, the content packet is received. The content acquisition unit 44 converts the received content packet into a video signal that can be output to the TV, and transmits the video signal to the TV 20 via the output unit 35. As a result, the content is displayed on the TV 20.

  In addition, when the content acquisition unit 44 finishes receiving the content, the content acquisition unit 44 notifies the band release request unit 45 to that effect. Note that whether or not the content has been received can be determined based on various conditions. As an example of the above condition, when a notification that the transmission to the end of the content is completed is received from the VoD server 12, a content reception end operation from the user is received via the input unit 34, For example, the elapsed time from the start of reception is measured using the timer 36, and the elapsed time reaches the required time of the related information received from the selection instruction acquisition unit 42.

  When the bandwidth release request unit 45 receives the notification of the end of content reception from the content acquisition unit 44, the bandwidth release request unit 45 sends a bandwidth release request for requesting to release the transmission bandwidth set by the request of the bandwidth setting request unit 43 to the communication unit. This is transmitted to the PLC master unit 15 via 33 or the like.

  Next, the flow of the processing operation of the content distribution system 11 having the above configuration will be described with reference to FIGS. FIG. 5 is a sequence diagram showing a flow of data transmitted in the content distribution system 11 of the present embodiment. FIG. 6 is a flowchart showing the flow of processing in the VoD server 12, the PLC master device 15, and the STB 17 of the content distribution system 11.

  As is clear from FIG. 2, communication between the VoD server 12 and the STB 17 is performed via the NGN network 13, the HGW 14, the PLC adapters 18 a and 18 c, and the PLC network 16. On the other hand, communication between the PLC master unit 15 and the STB 17 is performed via the PLC adapters 18 b and 18 c and the PLC network 16. Therefore, in the following, in order to simplify the description, description of a device that relays data is omitted.

  As shown in FIGS. 5 and 6, first, in STB 17, the related information acquisition unit 41 requests the VoD server 12 via the communication unit 33 for the related information of the content that can be provided by the VoD server 12 (step S10). .

  The content that can be provided is an expression viewed from the VoD server 12, and can be said to be content that can be selected by the user when viewed from the STB 17. In addition, the STB 17 requests related information of all contents that can be selected and viewed by the user. However, the STB 17 adds a condition desired by the user to the request, and only the related information of the content that matches the condition. You may make it request. In addition, the transmission of the request may be automatically performed at a predetermined timing such as when the power of the STB 17 is turned on or when a predetermined time is reached as described above, or the user may input the input unit 34. You may perform at the timing which instruct | indicates via.

  On the other hand, when receiving the request for content related information from the STB 17, the VoD server 12 transmits the related information of the content that can be provided to the STB 17 that is the request source (step S20). At this time, when there are a plurality of contents that can be provided, the related information of the plurality of contents is arranged in one list and transmitted collectively.

  The VoD server 12 may be able to provide all of the content that it holds, or may select and provide content that matches a predetermined condition from the content that it holds. The predetermined condition may be set based on a contract between the service provider that provides the content and the user who receives the content. For example, whether or not the content can be viewed is set by the content provision fee, For example, whether or not viewing is set for each natural person or corporation having the copyright of the content, and whether or not viewing is set for each genre of the content (movie, sports, drama, animation, etc.).

  In addition, when a condition desired by the user, for example, a condition such as a required time of 1 hour or less is added to the request from the STB 17, the VoD server 12 further selects content that matches the condition, The related information of the selected content is transmitted to the requesting STB 17.

  On the other hand, in the STB 17, the related information acquisition unit 41 acquires the related information of the content transmitted from the VoD server 12 via the communication unit 33, and stores (stores) it in the related information storage unit 46 (step S11). Note that the STB 17 may continue to hold the related information stored in the related information storage unit 46 until the user instructs the re-acquisition of the related information of the content. In this case, since the user does not need to request and acquire the related information from the VoD server 12 every time the user wants to view the content, the related information can be provided quickly.

  Next, in STB 17, the related information acquisition unit 41 causes the user to refer to the related information by performing processing such as outputting the related information to the TV 20 via the output unit 35 and displaying it. Then, the user selects the title name of the content desired to be viewed and gives an instruction via the input unit 34, whereby the selection instruction acquisition unit 42 acquires the content selection instruction from the user (step S12). .

  At this time, in STB 17, the selection instruction acquisition unit 42 searches the related information in the related information storage unit 46 for the bit rate (bandwidth information) corresponding to the title name of the content selected by the user. Next, in order to secure a transmission band corresponding to the searched bit rate in the PLC network 16, a band setting request for requesting setting of the transmission band is sent from the band setting request unit 43 via the communication unit 33 to the PLC parent. It transmits to the machine 15 (step S13).

  For example, referring to the related information shown in FIG. 4, when the user selects to view content whose title name is ABC, a transmission band corresponding to the bit rate of 10 Mbps corresponding to the title name is set for the STB 17 As described above, the bandwidth setting request unit 43 requests the PLC master unit 15.

  When the user selects content, if the number of contents that can be provided by the VoD server 12 is larger than the number of contents that can be displayed on the TV at a time, only the number that can be displayed on the selection screen is displayed. Even if the related information is acquired and the user makes a request to display further content (for example, when an operation for displaying the next page of the content list is performed), the following related information is provided. It is good, and first, the related information of all the contents that can be provided by the VoD server 12 is provided and stored in the related information storage unit 46 of the STB 17, and when the user makes a request to display further contents The related information may be acquired from the related information storage unit 46.

  On the other hand, when receiving the bandwidth setting request from the STB 17, the PLC master device 15 starts transmission band setting processing in the PLC network 16 (step S30), and notifies the request source STB 17 of the setting result (step S31). . That is, the PLC master unit 15 considers the use status of the PLC network 16 by other devices, for example, “cannot be set” when the transmission band is not available, and the bandwidth requested by the STB 17 when the transmission band is available. If the request can be secured, the setting result such as “setting completed” is notified to the requesting STB 17.

  On the other hand, when the band setting request unit 43 receives the setting result from the PLC master device 15 via the communication unit 33, the STB 17 determines whether or not the transmission band has been successfully set (step S14). When the above setting fails (NO in step S14), the control unit 31 notifies the user by displaying information indicating that the transmission band could not be set via the output unit 35 and the TV 20. (Step S15). Thereafter, the processing operation of the content distribution system 11 is terminated. Instead of ending the processing operation, after waiting for a predetermined time, the processing may be repeated by returning to step S13.

  On the other hand, when the setting is successful (YES in step S14), the content acquisition unit 44 includes the title name corresponding to the content in the viewing request (content transmission request) of the content selected by the user, and VoD. It transmits to the server 12 (step S16).

  On the other hand, when receiving the viewing request from the STB 17, the VoD server 12 packetizes the content corresponding to the title name included in the viewing request and transmits it to the requesting STB 17 (step S21). At this time, in the STB 17, the content acquisition unit 44 receives the packet from the VoD server 12 via the communication unit 33, reconstructs the received packet as a video signal, and transmits it to the TV 20 via the output unit 35. Are displayed (step S17).

  Then, when the transmission of the content is completed, the VoD server 12 transmits a notification to that effect to the STB 17 (step S22). On the other hand, in the STB 17, when the content acquisition unit 44 acquires the notification via the communication unit 33 (step S18), a bandwidth release request requesting to release the transmission band set in step S30 is sent to the bandwidth release request unit. 45 transmits to the PLC main unit 15 via the communication unit 33 (step S19).

On the other hand, when receiving the band release request from the STB 17, the PLC master unit 15 releases the transmission band set for the STB 17 so that it can be used by other devices (step S32). Then, the PLC master device 15 transmits a release completion notification indicating that the release has been completed to the requesting STB 17 (step S33). Thereafter, the processing in the content distribution system 11 ends. Alternatively, the content list may be displayed again on the TV so that the user can select the content to be viewed next. (That is, you may return to step S12.)
The processing operations of the content distribution system 11 as described above can be summarized as follows according to the above-described parameter-guaranteed QoS technology.

  The PLC master unit 15 manages the transmission band of the entire PLC network 16. Specifically, the PLC master unit 15 as the master station manages the transmission band usage schedule in the entire PLC network 16 according to the QoS parameters requested from the PLC adapter 18 as the slave station, and all the PLC adapters 18 are connected. Centrally manages the number of transmissions and transmission time.

  Under such circumstances, when the user decides the content desired to be viewed, it is necessary to secure a necessary transmission band in the PLC network 16 in order to receive the content from the VoD server 12 without delay. Therefore, the STB 17 sends a QoS transmission request signal (band request) including a QoS parameter such as a band setting request based on the band information (bit rate) of the content included in the related information acquired in advance. And transmitted to the PLC master unit 15 via the PLC adapter 18c.

  At this time, the PLC master unit 15 interprets the QoS parameter received from the STB 17 via the PLC adapter 18c, and considers the usage status of the PLC network 16 when viewing the content, and can the requested QoS be realized? Judge whether. If feasible, QoS transmission is permitted, and if not feasible, it is rejected.

  For example, when the STB 17 requests QoS transmission as described above, the PLC adapter 18 other than the PLC adapter 18c to which the STB 17 is connected is not performing QoS transmission or requested bit rate even if it is performed. When the transmission band corresponding to is left, QoS transmission is permitted to the STB 17 (PLC adapter 18c connected to the STB 17). On the other hand, when another PLC adapter 18 is already performing QoS transmission and there is no sufficient bandwidth, the PLC master unit 15 sends QoS to the STB 17 (PLC adapter 18c connected to) STB17. Reject transmission.

  Thus, the PLC master unit 15 always manages the transmission band allocation schedule so that the QoS for each PLC adapter 18 is guaranteed, and transmits the transmission permission signal to the corresponding PLC adapter 18 according to the schedule. . Each PLC adapter 18 can perform data communication only during the period notified by the transmission permission signal.

  With such a mechanism, there is no access contention in the entire PLC network 16, so that when the QoS transmission is permitted, the STB 17 can receive the desired content in a state where transmission delay, jitter, and the like are within specific conditions. In particular, the STB 17 does not acquire the bandwidth information of the content from the VoD server 12 every time the content to be viewed changes, but collectively acquires the related information of the content including the bandwidth information in advance. However, this is different from the conventional parameter guaranteed QoS. Due to this difference, it is not necessary to acquire the related information of the selected content every time the content is selected, so that the bandwidth setting and the like can be performed quickly.

  When the transmission completion notification indicating that the content transmission is completed is transmitted from the VoD server 12, the STB 17 transmits the band release request to the PLC master unit 15 via the PLC adapter 18c. Then, the PLC master device 15 releases the transmission band set for the STB 17 and transmits a release completion notification to the STB 17. Even if information indicating that the content transmission has ended is not transmitted from the VoD server 12, it detects that a certain time has elapsed since the STB 17 no longer receives the content packet, and transmits a bandwidth release request. May be. In addition, a signal indicating the end of the content may be included in the packet transmitted last among the content data packets, and the band release request may be transmitted by detecting the signal in the STB 17.

[Embodiment 2]
Next, another embodiment of the present invention will be described with reference to FIG. In the content distribution system 11 shown in FIGS. 2 to 6, the STB 17 sends a content transmission completion notification from the VoD server 12 in response to a bandwidth release request (step S19 in FIGS. 5 and 6) from the STB 17 to the PLC master unit 15. It is done when received. On the other hand, in the present embodiment, the bandwidth release request is made when the elapsed time from the start of content reception by the STB 17 reaches the required time included in the content related information. Other configurations and processing operations are the same as those of the content distribution system 11 shown in FIGS. 2 to 6, and thus the same reference numerals are given and description thereof is omitted.

  As shown in FIG. 4, time information required for content transmission is included as “required time” in the content related information. For example, the related information whose title is ABC includes a required time of 1 hour 00 minutes. Therefore, in the present embodiment, the STB 17 transmits a bandwidth release request to the PLC master device 15 when the time indicated by the required time has elapsed since the start of content reception.

  FIG. 7 is a flowchart showing a main part of the processing flow in the STB 17 of the content distribution system 11 of the present embodiment. The processing of the VoD server 12 and the PLC master device 15 is the same as the processing shown in FIG. Also, as shown in FIG. 7, the processing (step S10 to step S16) from the request for the content related information to the viewing request is the same as the processing shown in FIG. .

  After the viewing request, when content reception from the VoD server 12 is started (step S40), the content acquisition unit 44 of the STB 17 starts the timer 36 (step S41).

  Next, content acquisition unit 44 receives data including the content from VoD server 12 (YES in step S42), and the data is not a notification of the completion of content transmission (in step S43). NO), since the received data is a content packet, the packet is reconstructed as a video signal and transmitted to the TV 20 via the output unit 35 (step S44). Thereby, content display, recording, and the like are performed. Thereafter, the process returns to step S42.

  On the other hand, when the received data is a notification of the completion of content transmission (YES in step S43), the bandwidth release request unit 45 transmits the bandwidth release request to the PLC master unit 15 as in FIG. After that, the processing operation of STB 17 is finished.

  On the other hand, when data including content is not received from the VoD server 12 (NO in step S42), the content acquisition unit 44 checks the value of the timer 36, and the value of the timer 36 is stored in the required time. It is determined whether or not a value obtained by adding a slight margin α to (step S45). If not reached (NO in step S45), content acquisition unit 44 returns to step S42 and repeats the above operation. On the other hand, if it has been reached (YES in step S45), the content acquisition unit 44 does not acquire the content transmission completion notification, and the value of the timer 36 has reached the required time + α. Judge that it is necessary to consider that there was. Then, similarly to FIG. 6, the bandwidth release request unit 45 transmits the bandwidth release request to the PLC master device 15 (step S19), and then ends the processing operation of the STB 17.

  According to the present embodiment, even if the content transmission is interrupted due to some reason such as a communication failure and the notification of the content transmission completion does not reach the STB 17, it is said that a certain band of the PLC network 16 is unnecessarily occupied. Inconvenience is eliminated. Even in normal transmission in which no communication failure occurs, the STB 17 does not necessarily need to receive the content transmission completion notification from the VoD server 12 in order to request the band release. Accordingly, the VoD server 12 does not necessarily have to transmit the content transmission completion notification.

  In the present embodiment, a method is used in which the timer 36 is started from 0 (zero) and waits until the stored required time + α is reached in step S45. However, for example, it is also possible to set the required time + α in the timer 36, decrease the value of the timer 36, and wait for the value of the timer 36 to become 0 (zero).

  Further, the time information (required time) in the present embodiment is a total time for transmitting the entire content, but may be a transmission interval of packets constituting the content. In this case, if the time between one packet and the next packet becomes larger than the value indicated by the time information in step S45, the bandwidth is released.

  The margin α can be appropriately determined according to the application and system. Further, the required time + α may be stored in the related information storage unit 46.

[Embodiment 3]
Next, still another embodiment of the present invention will be described with reference to FIGS. Compared to the content distribution system 11 shown in FIGS. 2 to 6, the content distribution system 11 according to the present embodiment is related information only on content selected based on a predetermined condition from all contents in the VoD server 12. The other configurations are the same. In addition, the same code | symbol is attached | subjected to the structure which has the function similar to the structure demonstrated in the said embodiment, and the description is abbreviate | omitted.

  In this embodiment, when receiving a request for content related information from the STB 17, the VoD server 12 transmits related information only for content selected under certain conditions, instead of always transmitting related information about all the contents held. To do. Hereinafter, this condition is referred to as a content selection condition.

  The content selection conditions are stored in advance in a storage device provided inside or outside the VoD server 12 in association with the identification information of the STB 17. Further, the content selection condition is determined at the time of contract and other arbitrary timings and is stored in the storage device. The content selection condition may be updated as needed.

  Various contents selection conditions are conceivable, but in the present embodiment, content that takes less than 2 hours based on a contract between the user of the STB 17 and the provider that provides the content from the VoD server 12. Are subject to the above selection. An example of the selection is shown in FIG.

  FIG. 8 is an explanatory diagram for explaining a configuration of related information of content selected by the VoD server 12. A) in FIG. 8 is related information of all contents held by the VoD server 12. FIG. 8B) shows an example in which content selection conditions in this embodiment, that is, contents that meet the condition that the required time is within 2 hours are selected.

  In the related information shown in FIG. 8B), the content whose required time exceeds 2 hours is excluded, and only the content within the required time of 2 hours is listed. That is, among the related information of FIG. 8A), the title name GHI (required time: 2 hours 10 minutes) and the title name XYZ (required time: 2 hours 30 minutes) are excluded from the related information of FIG. Has been.

  As a result, the STB 17 stores the related information of only the content that can be viewed based on the contract, so it is not necessary to manage unnecessary related information, and the user can easily select the content. In addition, since the selection is automatically performed by the VoD server 12 based on the contract, the STB 17 does not need to be aware that the selection is performed.

  Next, the operation of the VoD server 12 in this embodiment will be described with reference to FIG. FIG. 9 is a flowchart showing a processing flow of the VoD server 12 according to the present embodiment.

  First, the VoD server 12 receives a request for content related information from the STB 17 (step S50). Next, the request source STB 17 that has transmitted the request is specified with reference to its address and the like (step S51). Next, the VoD server 12 extracts content selection conditions corresponding to the identified STB 17 from the storage device (step S52).

  Next, the VoD server 12 extracts the related information of the content that matches the content selection condition (within the required time of 2 hours) from the related information of all the content (step S53). In the example of A) of FIG. 8, related information of three contents whose title names are ABC, DEF, and PQR are extracted.

  Then, the VoD server 12 organizes the related information of the extracted three contents as shown in B) of FIG. 9 into a list, and transmits them collectively to the requesting STB 17 (step S54). Thereafter, the VoD server 12 ends the transmission process of the related information on the content based on the request.

  There are various other content selection conditions (filtering conditions), for example, content whose price is a certain value or less, but since it can be realized by the same control, its description is omitted.

  In the present embodiment, the VoD server 12 automatically selects (filters) content-related information based on the content selection conditions determined at the contract and other arbitrary timings and stored in the VoD server 12. However, the content selection condition can be added to the command for the STB 17 to request the related information of the content. In this case, the content selection condition added to the command is taken into consideration by the VoD server 12, and the related information of the content that matches the condition is selected and transmitted to the STB 17 at once. The setting of the content selection condition in the STB 17 may be performed at the time of requesting the content related information, or may be performed in advance before the request. An example of the command is shown in FIG.

  FIG. 10 is an explanatory diagram showing a command for the STB 17 to request content related information from the VoD server 12. FIG. 10A shows the format of the command, and FIG. 10B shows a specific example of the command. In FIG. 10B), the command is a conditional related information request command including “content information request” as a command type and “required time within 2 hours” as a condition. Upon receiving this command, the VoD server 12 selects the information corresponding to “within 2 hours required” from the related information of all the contents held, and transmits it to the requesting STB 17 collectively.

  In the case of the above method for adding the content selection condition to the command, the user of the STB 17 can set the content selection condition. Further, since the content selection condition can be set every time the content related information is requested, it can be said that it is more flexible than the fixed content selection condition set at the time of contract.

[Embodiment 4]
Next, still another embodiment of the present invention will be described with reference to FIGS. FIG. 11 is a schematic diagram showing the configuration of the content distribution system 11 of the present embodiment. The content distribution system 11 shown in FIG. 11 is provided with an IP broadcast server 50 that performs IP broadcast of content in place of the VoD server 12 as compared to the content distribution system 11 shown in FIGS. Other than that a recorder 51 connected to the STB 17 is added, other configurations are the same. In addition, the same code | symbol is attached | subjected to the structure which has the function similar to the structure demonstrated in the said embodiment, and the description is abbreviate | omitted.

  When the server that provides the content is not the VoD server 12 but the IP broadcast server 50 that performs IP broadcasting, it cannot be viewed immediately when the user wants to view the content, and must wait for the distribution of the desired content until the broadcast start time. . Therefore, in the present embodiment, band information required for content transmission is added for each content in the EPG (electronic program guide) provided from the IP broadcast server 50. Thus, by acquiring EPG including the band information of each content from the IP broadcast server 50 in advance, the transmission band can be set in advance before viewing or recording, and convenience is improved.

  Returning to FIG. 11, the recorder 51 can perform reserved recording based on a command from the STB 17. Since the IP broadcast server 110 broadcasts the program regardless of the user's viewing according to the EPG, it is necessary for the user to set the recorder 51 so that the recording can be performed in accordance with the broadcast time.

  Next, the flow of the processing operation of the content distribution system 11 having the above configuration will be described with reference to FIGS. FIG. 12 is a sequence diagram showing a flow of data transmitted in the content distribution system 11 of the present embodiment. FIG. 13 is a flowchart showing a process flow in the IP broadcast server 50, the PLC master device 15, and the STB 17 of the content distribution system 11.

  As is clear from FIG. 11, communication between the IP broadcast server 50 and the STB 17 is performed via the NGN network 13, the HGW 14, the PLC adapters 18 a and 18 c, and the PLC network 16. On the other hand, communication between the PLC master unit 15 and the STB 17 is performed via the PLC adapters 18 b and 18 c and the PLC network 16. Therefore, in the following, in order to simplify the description, description of a device that relays data is omitted.

  As shown in FIGS. 12 and 13, first, in STB 17, the related information acquisition unit 41 requests the IP broadcast server 50 via the communication unit 33 to transmit an EPG to the IP broadcast server 50 (step S60). The request may be transmitted automatically at a predetermined timing such as when the STB 17 is turned on or when a predetermined time has been reached, or the user may instruct via the input unit 34. It may be done at the timing.

  On the other hand, upon receiving an EPG request from the STB 17, the IP broadcast server 50 transmits the EPG to the requesting STB 17 (step S80). This EPG includes a bit rate, which is band information for each program, in addition to the normal channel, program title name, and program broadcast time. This bit rate varies depending on the content compression method, compression rate, and the like.

  FIG. 14 is an explanatory diagram showing an example of the EPG. In the case of the figure, in “Channel 1” (CH1), a program titled “AAA” is broadcast at a bit rate of 15 Mbps from 8:00 to 9:00, followed by a title “BBB” from 9:00 to 9:15. This shows that a program with a name is broadcast at a bit rate of 5 Mbps. In “Channel 2” (CH2), a program titled FFF is broadcast from 8:30 to 11:00 at a bit rate of 10 Mbps, and in “Channel 3” (CH3), 10:10 to 11:00. It shows that a program with the title HHH is broadcast at a bit rate of 15 Mbps. Since the other columns in FIG. 14 can be understood in the same manner, the description will not be repeated. However, these numbers are for convenience of explanation, and are actually determined by the compression method and compression rate of the broadcast content.

  Returning to FIGS. 12 and 13, in STB 17, EPG transmitted from IP broadcast server 50 is acquired by related information acquisition unit 41 via communication unit 33 and stored (stored) in related information storage unit 46 ( Step S61). Note that the STB 17 may continue to hold the EPG stored in the related information storage unit 46 until the user gives an instruction to reacquire the EPG. In this case, since the user does not need to request and acquire the EPG from the IP broadcast server 50 every time the user wants to view and / or record a program (content), the user can quickly provide the EPG. .

  Next, in STB 17, the related information acquisition unit 41 performs processing such as outputting the EPG to the TV 20 via the output unit 35 and displaying it, thereby causing the user to refer to the EPG. Then, when the user selects the title name of the program desired to be viewed and / or recorded and gives an instruction via the input unit 34, the selection instruction acquisition unit 42 acquires the program selection instruction from the user. (Step S62).

  At this time, in STB 17, the selection instruction acquisition unit 42 searches the EPG in the related information storage unit 46 for the broadcast start time, broadcast end time, and bit rate (band information) corresponding to the title name of the program selected by the user. (Step S63). Next, in order to secure a transmission band corresponding to the searched bit rate in the PLC network 16 in the searched broadcast time zone (broadcast start time to broadcast end time), the above-described broadcast time zone and bit rate are set to the band setting request unit 43. Is transmitted to the PLC master unit 15 via the communication unit 33. As a result, the STB 17 requests the PLC master unit 15 to set a transmission band in a time zone during which a desired program is broadcast (step S64). That is, the band setting request unit 43 requests reservation of a transmission band necessary for broadcasting a program selected between the broadcast start time and the broadcast end time.

  On the other hand, when receiving the transmission band reservation request from the STB 17, the PLC master device 15 performs transmission band reservation processing in the PLC network 16 (step S90). Conventionally, the PLC master unit manages only the bandwidth usage status at the current time, but the PLC master device 15 in this embodiment manages the bandwidth reservation status up to a future time. Therefore, the PLC master unit 15 has a function of storing date and time zone information and the total amount of bandwidth already reserved in the time zone. For example, information is stored that the total amount of bandwidth reserved from 6 pm to 6:30 pm on September 4 is 30 Mbps. These pieces of information are calculated every time a bandwidth reservation request is received, and the record is updated. And when a new bandwidth reservation request is made, it is possible to compare the size of the bandwidth already reserved in the requested time zone with the newly requested bandwidth size to satisfy the request. Determine whether or not.

  The PLC master unit 15 notifies the request source STB 17 of the determination result as described above (step S91). Thereafter, the PLC master device 15 repeats other general processes until the broadcast end time is reached (steps S92 and S93).

  On the other hand, when the band setting request unit 43 receives the reservation result from the PLC master unit 15 via the communication unit 33, the STB 17 determines whether or not the transmission band reservation setting is successful (step S65). . If the reservation setting fails (NO in step S65), control unit 31 determines whether or not the transmission band reservation request has reached the number of retries (step 66). If the number of retries has not been reached (NO in step S66), the process returns to step S64 to repeat the transmission band reservation request. On the other hand, when the number of retries has been reached (YES in step S66), the control unit 31 displays and outputs information indicating that the transmission band could not be reserved via the output unit 35 and the TV 20 to the user. Notification is made (step S67). Thereafter, the processing operation of the content distribution system 11 is terminated. Note that if a retry is made immediately after requesting a bandwidth once, the usage status of the bandwidth has not changed and there is a high possibility that the reservation setting will similarly fail. Therefore, the retry may be performed at regular time intervals. .

  On the other hand, if the reservation setting has succeeded (YES in step S65), the control unit 31 instructs the recorder 51 to make a recording reservation in the broadcast time period (step S68). Then, it waits until it reaches the broadcast start time (step S69). Note that the IP broadcast server 50 broadcasts regardless of the usage status of the user until the broadcast start time is reached, but the STB 17 does not watch unless there is an instruction from the user.

  When the broadcast start time is reached (YES in step S69), the IP broadcast server 50 starts broadcasting the program (step S81), while in STB 17, the content acquisition unit 44 selects a reserved channel. Then, the broadcast data from the IP broadcast server 50 is transferred to the recorder 51 (step S70). On the other hand, the recorder 51 receives and records a program in accordance with the selected channel. At this time, since the transmission band is also reserved and secured, broadcast data with a disordered video is not recorded. Note that the video of the program may be displayed by transmitting the video signal of the program to the TV 20 via the output unit 35.

  Thereafter, the program reception and recording (step S70) are repeated until the broadcast end time is reached (step S71). When the broadcast end time is reached (YES in step S71), STB 17 instructs recorder 51 to stop the recording (step S72). Thereafter, the processes in the IP broadcast server 50 and the STB 17 are terminated. Further, the recorder 51 stops the recording based on the instruction from the STB 17 and ends the process.

  On the other hand, when reaching the broadcast end time (YES in step S93), PLC master device 15 releases the transmission band set for STB 17 so that it can be used by other devices (step S94). Thereafter, the processing of the PLC master unit 15 is terminated.

  In step S69, it is determined whether or not the broadcast start time has been reached. In steps S71 and S93, it is determined whether or not the broadcast end time has been reached. Therefore, in step S69, it is determined whether or not a time slightly earlier than the broadcast start time has been reached, and in steps S71 and S93, it is determined whether or not a time slightly later than the broadcast end time has been reached. In addition, it is desirable to make a determination by adding a margin to the regular broadcasting time zone from the viewpoint of preventing a processing timing cooperation error.

  In the present embodiment, the PLC master unit 15 automatically sets the transmission band when the broadcast start time is reached, and automatically releases the transmission band when the broadcast end time is reached. As in the above-described embodiment, the transmission band may be set or released based on a request from the STB 17.

  In the present embodiment, when a program is selected (step S62), the STB 17 requests the PLC master unit 15 to reserve a transmission band (step S64), and the PLC master unit 15 reserves a bandwidth until a future time. Although the situation is managed, the bandwidth reservation information designated by the user may be stored in the STB 17 and a transmission band may be requested from the PLC master unit 15 a certain time before the broadcast start time is reached. . However, in this case, since it is not possible to determine whether or not the bandwidth can be secured unless it is just before the reserved time, the user has recorded the recorded video because the bandwidth was not secured even though the reserved recording was performed. Since the problem of being disturbed arises, it is desirable to manage the bandwidth reservation status until the future time in the PLC master unit 15.

[Embodiment 5]
Next, another embodiment of the present invention will be described with reference to FIGS. FIG. 15 is a schematic diagram showing the configuration of the content distribution system 11 of the present embodiment. The content distribution system 11 shown in FIG. 15 is different from the content distribution system 11 shown in FIG. 2 in that the content is stored in a plurality of servers and the related information of the content is stored in another server. Unlike the above, other configurations are the same. In addition, the same code | symbol is attached | subjected to the structure which has the function similar to the structure demonstrated in the said embodiment, and the description is abbreviate | omitted.

  As shown in FIG. 15, the content distribution system 11 of the present embodiment has a VoD server A 60, a VoD server B 61, and a related information server 62 instead of the VoD server 12, as compared with the content distribution system 11 shown in FIG. 2. Is provided.

  The VoD server A 60 and the VoD server B 61 store the content in a storage device (not shown) and transmit the content in response to the request in the same manner as the VoD server 12, but unlike the VoD server 12, the related information of the content Is not stored in the storage device. Since the related information of the content is stored in a storage device (not shown) of the related information server 62, it is requested and acquired from the related information server 62.

  FIG. 16 shows an example of content-related information used in the present embodiment. The content-related information shown in FIG. 16 differs from the content-related information shown in FIG. 4 in that a server name column is added, and the others are the same. The server name column stores the server name where the content is actually saved. The server name A corresponds to the VoD server A60, and the server name B corresponds to the VoD server B61. Further, it is assumed that it is known in advance that the related information of the contents stored in the VoD server A 60 and the VoD server B 61 is stored in the related information server 62.

  Therefore, the content acquisition unit 44 of the STB 17 requests the server having the server name corresponding to the content title name to transmit the content. For example, when a content whose title is ABC is selected by the user, the STB 17 requests the PLC master unit 15 to secure a transmission bandwidth of 10 Mbps on the PLC network 16, and then stores the content on the VoD server A60. It will require transmission. Also, for example, when a content whose title name is GHI is selected by the user, the STB 17 requests the PLC master unit 15 to secure a transmission band of 15 Mbps on the PLC network 16, and then sends it to the VoD server B61. The transmission of content is requested.

  Next, the flow of the processing operation of the content distribution system 11 having the above configuration will be described with reference to FIGS. FIG. 17 is a flowchart showing the flow of processing in the VoD server A 60, the VoD server B 61, the related information server 62, and the STB 17 of the content distribution system 11. Note that the processing related to the setting and release of the transmission band in the content distribution system 11 of the present embodiment is the same as the processing shown in FIG. 6, and is omitted in FIG.

  As shown in FIG. 17, first, in STB 17, related information acquisition unit 41 requests related information server 62 via communication unit 33 for related information of content that can be provided by VoD server A 60 and VoD server B 61 (steps). S100).

  On the other hand, when the related information server 62 receives a request for content related information from the STB 17, the related information server 62 transmits the related information of the content that can be provided (see FIG. 16) to the requesting STB 17 (step S 110). Thereafter, the processing in the related information server 62 ends.

  On the other hand, in the STB 17, the related information acquisition unit 41 acquires the related information of the content transmitted from the related information server 62 via the communication unit 33, and stores (stores) it in the related information storage unit 46 (step S101). Next, in STB 17, the related information acquisition unit 41 causes the user to refer to the related information by performing processing such as outputting the related information to the TV 20 via the output unit 35 and displaying it. Then, when the user selects the title name of the content desired to be viewed and gives an instruction via the input unit 34, the selection instruction acquisition unit 42 acquires the content selection instruction from the user (step S102). .

  At this time, in STB 17, the selection instruction acquisition unit 42 searches the related information in the related information storage unit 46 for the bit rate (bandwidth information) corresponding to the title name of the content selected by the user. Next, the bandwidth setting request unit 43 transmits a bandwidth setting request for setting the transmission band corresponding to the searched bit rate to the PLC master unit 15 via the communication unit 33, so that the transmission band is set. It is secured on the PLC network 16 (step S103).

  Next, in STB 17, the selection instruction acquisition unit 42 searches (extracts) server information (server name) corresponding to the title name of the content selected by the user from the related information in the related information storage unit 46. If the extracted server information is A, the process proceeds to step S105. If the extracted server information is B, the process proceeds to step S107.

  In step S105, the content acquisition unit 44 of the STB 17 requests the VoD server A60 to transmit the content. At this time, the VoD server A 60 transmits the content based on the request (step S120). Then, the content acquisition unit 44 of the STB 17 acquires content from the VoD server A60 (step S106).

  On the other hand, in step S107, the content acquisition unit 44 of the STB 17 requests the VoD server B61 to transmit the content. At this time, the VoD server B61 transmits the content based on the request (step S130). Then, the content acquisition unit 44 of the STB 17 acquires content from the VoD server B61 (step S108). The subsequent processing is the same as the processing shown in FIG.

  In each embodiment, the server 2 (VoD servers 12, 60, 61, IP broadcast server 50, related information server 62, etc.) is connected to the first network 3 (NGN network 13), and the communication device 7 In communication with (STB 17 and the like), communication is performed via two networks, the first network 3 and the second network 6 (PLC network 16). However, the number of networks through which communication is performed is arbitrary.

  For example, in FIG. 2, the VoD server 12 may be connected to the PLC network 16 instead of the NGN network 13. In this case, the VoD server 12 and the STB 17 communicate via the PLC network 16 only. That is, the server 2 and the communication device 7 communicate via only one network. In this case, HGW is not necessary.

  As another example, in FIG. 2, even if the NGN network 13 is connected to another network (for example, a network provided by a vendor different from the NGN network 13), and the VoD server 12 is connected to the network. Good. In this case, the VoD server 12 and the STB 17 perform communication via another network in addition to the NGN network 13 and the PLC network 16. That is, the server 2 and the communication device 7 communicate via three networks.

  Furthermore, when there are a plurality of servers 2 as shown in FIG. 15, the number of networks through which each server 2 communicates with the communication device 7 may be different, and the paths are different. Also good.

  When a plurality of servers are connected to the PLC network, the PLC adapter 18 may be connected to each server by Ethernet (registered trademark), or the plurality of servers and one PLC adapter 18 are connected by an Ethernet hub. A plurality of servers may be connected to the PLC network by one PLC adapter 18.

  In addition, VoD and IP broadcasting are assumed as content distribution methods, but the present invention can also be applied when other content distribution methods are used. For example, a content distribution method in accordance with guidelines defined by DLNA (Digital Living Network Alliance) may be used. In this case, as the communication device 7, a device having a DMP (Digital Media Player) function such as a TV, an HDD recorder, a DVD (Digital Versatile Disc) recorder, a game machine, a PC (Personal Computer), or an STB in accordance with the DLNA guidelines. Corresponding to this, the server 2 corresponds to a device having a DMS (Digital Media Server) function such as an HDD recorder, a DVD recorder, a game machine, a PC, and an STB in accordance with the DLNA guidelines. Since DLNA is basically used for content distribution in the home, the server 2 and the communication device 7 generally communicate only via the second network 6 (PLC network).

  In each embodiment, the HomePlugAV system is assumed as a communication protocol used in the PLC network 16, but the present invention can also be applied when another communication protocol is used. Further, instead of the PLC network 16, a network of another communication medium may be used. For example, the present invention can be applied to a case where IEEE (Institute of Electrical and Electronics Engineers) 802.11a, IEEE802.11b, IEEE802.11g, IEEE802.11e, and IEEE802.11n, which are wireless LAN communication protocols, are used.

  As described above, the content and the related information need not be collectively stored in one server, and can be stored in separate servers. In addition, it is not necessary to store all contents on one server at a time, and it is also possible to store them on separate servers.

  As described above, according to the present invention, before the data to be received is selected by the user, the bandwidth information of the selectable data is acquired at a time. Since it is not necessary to inquire and acquire the bandwidth information from the data bandwidth information management source, the bandwidth can be set quickly.

  In addition, the present invention acquires in advance the data selectable by the user and the corresponding band information in advance, so that when data distribution is reserved, for example, typically when video content is reserved for recording. Therefore, it is not necessary to acquire bandwidth information every time a reservation occurs, and unnecessary traffic is not generated.

  Further, according to the present invention, since the data information to be acquired includes time information indicating the time required for data transmission, even if communication is stopped during data reception, the time information When the indicated time elapses, the band can be released and unnecessary band occupation can be avoided.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  For example, although the video content has been described in the above embodiment, the present invention can also be applied to other data such as audio content and AV (Audio-Visual) content.

  Finally, each block of the VoD server 12, the PLC master unit 15, and the STB 17, in particular, the control unit 31 may be configured by hardware logic, or may be realized by software using a CPU as follows. .

  That is, the VoD server 12, the PLC master unit 15, and the STB 17 expand a CPU (central processing unit) that executes instructions of a control program for realizing each function, a ROM (read only memory) that stores the program, and the program. A random access memory (RAM), and a storage device (recording medium) such as a memory for storing the program and various data. An object of the present invention is to read the program code (execution format program, intermediate code program, source program) of the control program of the VoD server 12, the PLC master unit 15, and the STB 17, which is software that realizes the functions described above, with a computer. The recording medium recorded as possible is supplied to the VoD server 12, the PLC master unit 15, and the STB 17, and the computer (or CPU or MPU) reads and executes the program code recorded on the recording medium. Achievable.

  Examples of the recording medium include a tape system such as a magnetic tape and a cassette tape, a magnetic disk such as a floppy (registered trademark) disk / hard disk, and an optical disk such as a CD-ROM / MO / MD / DVD / CD-R. Card system such as IC card, IC card (including memory card) / optical card, or semiconductor memory system such as mask ROM / EPROM / EEPROM / flash ROM.

  Further, the VoD server 12, the PLC master unit 15, and the STB 17 may be configured to be connectable to a communication network, and the program code may be supplied via the communication network. The communication network is not particularly limited. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication. A net or the like is available. Further, the transmission medium constituting the communication network is not particularly limited. For example, even in the case of wired communication such as IEEE 1394, USB, power line carrier communication, cable TV line, telephone line, ADSL line, etc., infrared rays such as IrDA and remote control, Bluetooth, etc. (Registered trademark), 802.11 wireless, HDR, mobile phone network, satellite line, terrestrial digital network, and the like can also be used. The present invention can also be realized in the form of a computer data signal embedded in a carrier wave in which the program code is embodied by electronic transmission.

  As described above, since the present invention can quickly receive desired content with appropriate quality, it can be applied not only to the distribution of video content, but also to the distribution of audio and other media content. It can also be applied to the transmission of data.

It is a block diagram which shows the basic structural example of the communication system with which this invention is applied. It is the schematic which shows the structure of the content delivery system which is one Embodiment of this invention. It is a block diagram which shows the principal part structure of STB in the said content delivery system. It is a figure which shows an example of the relevant information of the content memorize | stored in the relevant information storage part of the said STB in a table format. It is a sequence diagram which shows the flow of the data transmitted in the said content delivery system. It is a flowchart which shows the flow of a process in the VoD server of the said content delivery system, PLC main | base station, and STB. It is a flowchart which shows the principal part of the flow of a process in STB of the content delivery system which is another embodiment of this invention. In the content delivery system which is further another embodiment of this invention, it is a figure which shows an example of the related information of the content before and behind the selection by a VoD server in a table format. It is a flowchart which shows the flow of a process of the said VoD server. It is explanatory drawing which shows the format and specific example of the command which STB in the said content delivery system requests | requires of the said VoD server. It is the schematic which shows the structure of the content delivery system which is another embodiment of this invention. It is a sequence diagram which shows the flow of the data transmitted in the said content delivery system. It is a flowchart which shows the flow of a process in IP broadcast server of the said content delivery system, PLC main | base station, and STB. It is a figure which shows an example of EPG which the said IP broadcast server transmits in a table format. It is the schematic which shows the structure of the content delivery system which is other embodiment of this invention. It is a figure which shows an example of the relevant information of the content utilized in the said content delivery system in a table format. It is a flowchart which shows the flow of the process in VoD server A of the said content delivery system, VoD server B, a related information server, and STB.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Communication system 2 Server 2 Patent document 3 1st network 4 Network relay apparatus 5 Network management apparatus (management apparatus)
6 Second network 7 Communication device 11 Content distribution system (data transmission system)
12, 60, 61 VoD server 13 NGN network 14 Home gateway (HGW)
15 PLC master unit 16 PLC network 17 Set top box (STB)
18.18a-18c PLC adapter 20 TV receiver 31 Control unit 32 Storage unit 33 Communication unit 34 Input unit 35 Output unit 36 Timer 41 Related information acquisition unit (related information acquisition unit, data selection unit, presentation unit)
42 Selection instruction acquisition unit (data selection means, reception means)
43 Band setting request part (Band setting request means)
44 Content acquisition unit (data transmission request means)
45 Bandwidth release request section (bandwidth release request means)
46 Related Information Storage 50 IP Broadcast Server 51 Recorder 62 Related Information Server

Claims (14)

A communication device connected to a network and receiving data from a server via one or more networks including the network,
Related information acquisition means for acquiring related information related to the data, the related information including at least band information indicating a band necessary for transmitting the data, with respect to a plurality of the data;
A storage unit for storing related information acquired by the related information acquisition unit;
Data selection means for selecting data to be received from the plurality of data;
To a management device that manages transmission of data in the network so that band information included in related information related to data selected by the data selection unit is read from the storage unit and band setting is performed based on the read band information. And a bandwidth setting request means for requesting the communication device. The related information includes identification information for identifying the data and the band information.
The data selection means is:
Presenting means for presenting at least identification information of the related information stored in the storage unit to the user;
The communication apparatus according to claim 1, further comprising: an accepting unit that accepts selection of the identification information by the user as the data to be received.   The communication device according to claim 2, wherein the presenting unit presents to the user whether or not band information is included in the related information regarding the data.   The communication device according to claim 2, wherein the presenting unit presents the identification information only for data in which band information is included in the related information.   2. The data transmission requesting unit according to claim 1, further comprising a data transmission requesting unit that requests the server to transmit the data when a notification that the band requested by the band setting requesting unit has been set is acquired from the management apparatus. Communication equipment. The related information includes required time information indicating a time required to transmit the data and the band information.
The required time information of the related information related to the data selected by the data selection means is read from the storage unit, and when the required time indicated by the read required time information has elapsed since the start of reception of the data, the request of the bandwidth setting request means The communication apparatus according to claim 1, further comprising: a band release requesting unit that requests the management apparatus to release the band set by.   2. The communication apparatus according to claim 1, wherein the related information acquisition unit requests a condition of data to be received from a server that provides the related information, and acquires related information that matches the condition. . Network,
A management device connected to the network and managing transmission of data in the network;
A communication system comprising: the communication apparatus according to claim 1 connected to the network.   9. The communication system according to claim 8, wherein the network is a power line carrier communication network. A communication system according to claim 8 or 9,
A data transmission system comprising: a server connected to the communication system via a network different from the network of the communication system, and transmitting data to the communication device.   The server transmits, to the communication device, related information on data that matches a predetermined condition corresponding to the communication device or related information on data that matches a condition requested by the communication device. 11. The data transmission system according to claim 10, wherein A method for controlling a communication device connected to a network and receiving data from a server via one or more networks including the network,
The related information related to the data, the related information including at least the band information indicating the band necessary for transmitting the data is acquired for the plurality of the data, and the acquired related information is stored in the storage unit A related information acquisition step;
A data selection step of selecting data to be received from the plurality of data;
A management apparatus that manages transmission of data in the network so that band information included in related information relating to the data selected in the data selection step is read from the storage unit and band setting is performed based on the read band information And a bandwidth setting requesting step for requesting to the communication device.   A communication device control program for operating the communication device according to any one of claims 1 to 7, wherein the communication device control program causes a computer to function as each of the means.   A computer-readable recording medium on which the communication device control program according to claim 13 is recorded.

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