JP4797054B2 - Data relay apparatus and data relay method - Google Patents

Description

  The present invention relates to a data relay device and a data relay method.

  When a communication terminal transmits a data transmission request to a server that provides content data such as a homepage and receives content data from the server, HTTP (Hypertext Transport Protocol) is generally used. When HTTP is used, data transmission / reception is performed by repeating a data transmission request and data transmission from the server as a set.

However, in a high-delay line such as wireless packet communication, for example, when acquiring a series of data in which a large number of image data is embedded, the data transmission / reception set described above is repeated many times. It takes longer time to acquire On the other hand, in Non-Patent Document 1, by transmitting an HTTP request by pipeline processing, after transmitting the first HTTP request (data transmission request) to the server, the data corresponding to the request is A technique related to “request pipelining (HTTP pipeline)” that shortens the time required for transmission / reception of a plurality of data by making a second HTTP request before being provided is described. This request pipelining is realized by using persistent connections (Persistent Connections) standardized in RFC (Request for Comments) 2616.
Network Working Group, Request for Comments: 2616 Hypertext Transfer Protocol-HTTP / 1.1, Fielding, et al., June1999

  However, the above request pipelining is effective when one communication path (TCP connection) is provided between the communication terminal and the server, and a plurality of HTTP requests are transmitted to the same server to receive data. However, when an HTTP request is transmitted to a plurality of servers and data is received, it is necessary to newly provide a communication path for each server, and a persistent connection cannot be used. Therefore, for example, when image data included in an HTML document is stored in a server different from the HTML document, request pipelining cannot be used, and a new communication path is provided for the server and an HTTP request is sent. It is necessary to acquire image data by repeating a transmission / reception set for transmitting and receiving image data. Thus, when receiving a series of data from a plurality of servers, there is a problem that request pipelining cannot be used.

  The present invention has been made in view of the above, and an object of the present invention is to provide a data relay apparatus and a data relay method capable of quickly receiving a series of data stored in a plurality of servers at a communication terminal.

  In order to achieve the above object, a data relay device according to the present invention is a data relay device that transmits data transmitted from a plurality of data servers to a communication terminal that communicates by connecting to a communication network. Data transmission request receiving means for receiving a data transmission request for transmitting data from the first data server, transmitted from the terminal, and data transmission to the first data server based on the data transmission request Data receiving means for receiving, from the first data server, data embedded with link information to object data held by the second data server by transmitting a request, and a second data server embedded in the data The dummy link information to the first data server is generated in association with the link information to the object data held by the Link information conversion processing means for embedding information in data instead of link information, data transmission means for transmitting data embedded with dummy link information to the communication terminal by the link information conversion processing means, and a link embedded in the data Link information storage means for associating and holding information and dummy link information generated by the link information conversion processing means, and transmission from the communication terminal based on the dummy link information embedded in the data, including dummy link information Corresponding to object data transmission request receiving means for receiving an object data transmission request for requesting transmission of object data from the first data server, and dummy link information included in the data transmission request stored in the link information storage means. Based on the link information An object data receiving means for receiving object data sent from the second data server, and sending the object data received by the object data receiving means to the communication terminal And an object data transmission means.

  Also, the data relay method according to the present invention transmits data transmitted from a plurality of data servers to a communication terminal that communicates by connecting to a communication network, and also performs data relay by a data relay device including link information storage means. A data transmission request receiving step for receiving a data transmission request for requesting data transmission from a first data server, which is transmitted from a communication terminal, and the first data server based on the transmission request A data receiving step for receiving, from the first data server, data embedded with link information to the object data held by the second data server by transmitting a data transmission request to the second data server; In association with the link information to the object data held by the second data server, A link information conversion processing step for generating link information and embedding the dummy link information in the data instead of the link information, and data transmission for transmitting the data in which the dummy link information is embedded in the link information conversion processing step to the communication terminal A link information storing step for associating the step, the link information embedded in the data, and the dummy link information generated in the link information conversion processing step in association with each other and holding the link information storage means; and the dummy link information embedded in the data The object data transmission request receiving step for receiving the object data transmission request for requesting the transmission of the object data from the first data server including the dummy link information transmitted from the communication terminal, and stored in the link information storage means Included in the data transmission request Object data reception for receiving object data transmitted from the second data server by transmitting a request for transmitting object data to the second data server based on the link information associated with the dummy link information And an object data transmitting step of transmitting the object data received in the object data receiving step to the communication terminal.

  According to the above data relay device and data relay method, instead of the link information included in the data transmitted from the first data server embedded with the link information to the object data held by the second data server, In the data relay device, dummy link information to the first data server is generated, embedded, and transmitted to the communication terminal. Therefore, it is recognized that the communication terminal transmits the object data transmission request to the same first data server as the data transmission source based on the dummy link information included in the data. Accordingly, object data transmission requests are continuously transmitted from the communication terminal. On the other hand, in the data relay device, since the link information storage means stores information in which link information and dummy link information are associated with each other, the object data to the first data server transmitted from the communication terminal using the dummy link information is stored. Also in response to the transmission request, it is possible to appropriately request the second data server to transmit the object data, and to transmit the object data transmitted from the second data server to the communication terminal. In this way, a series of data stored in the first data server and the second data server is received at the communication terminal faster than in the past.

  Here, as a configuration that effectively exhibits the above-described operation, specifically, the data relay device performs transmission / reception using HTTP with the communication terminal, the first server, and the second server. Is mentioned.

  ADVANTAGE OF THE INVENTION According to this invention, the data relay apparatus and data relay method which can receive a series of data preserve | saved at a some server quickly in a communication terminal are provided.

  The best mode for carrying out the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a diagram showing a configuration of a communication system 1 including a data relay device according to a preferred embodiment of the present invention. A communication system 1 shown in FIG. 1 includes a data relay device 10, a communication terminal 20 that communicates with the data relay device 10 via a mobile communication network N 1, and the data relay device 10 and the Internet network N 2. And a first data server 30 and a second data server 40 connected via the network. The mobile communication network N1 is, for example, a network provided by a communication carrier or the like so that the communication terminal 20 performs packet communication. The Internet N2 is a network connected using a communication protocol TCP / IP (Transmission Control Protocol / Internet Protocol).

  When the communication terminal 20 acquires data from the first data server 30 or the second data server 40 by communication via the mobile communication network N1, the data relay device 10 and the first data server 30 And an apparatus (HTTP Proxy server) that relays data transmission / reception using HTTP via the communication path provided with a communication path (TCP connection) between the second data server 40 and the second data server 40. And the data relay apparatus 10 transmits the data hold | maintained in the 1st data server 30 and the 2nd data server 40 with respect to the communication terminal 20 via an own apparatus based on the request | requirement from the communication terminal 20. Have The data relay device 10 further has a function as a GW (Gateway) device that connects the mobile communication network N1 and the Internet N2.

  Note that “data” in the present embodiment indicates, for example, audio data, image data, document data described in HTML (HyperText Markup Language), and the like. The “series of data” in the present embodiment refers to, for example, data (web page) of one HTML document described in HTML, and object data (link data embedded in the document data) Image data, etc.). That is, in order to output information included in the HTML document data to the user, a plurality of data that needs to be acquired together with the HTML document data in the communication terminal 20 is referred to as a series of data. Here, the “link information” includes information for specifying a data server in which object data embedded in document data is held, and information for specifying object data among data held in the data server. And are included. The “series of data” in this embodiment does not include other HTML documents (web pages) specified by link information described in the HTML document. Whether or not each piece of link information described in the HTML document corresponds to information specifying “a series of data” is determined based on, for example, whether or not the tag in the HTML document is a specific tag.

  Information is exchanged between the communication terminal 20 and the data relay apparatus 10 by wireless communication via the mobile communication network N1, but communication via a wired network may be performed. Further, the data relay device 10 and the first data server 30 and the data relay device 10 and the second data server 40 are respectively connected via a wired network. Information transmission / reception is performed between the data relay device 10 and the communication terminal 20, the first data server 30, and the second data server 40 using HTTP.

  In FIG. 1, one communication terminal 20 is connected to the data relay apparatus 10, but actually a plurality of communication terminals are connected. Moreover, although the server of the 1st data server 30 and the 2nd data server 40 is shown as a server connected with the data relay apparatus 10, two or more servers are actually arrange | positioned. In the present embodiment, as an example of transmitting a series of data from a plurality of servers to the communication terminal 20, document data described in HTML among the series of data is stored in the first data server 30, and the document data The case where the object data included in is stored in the second data server 40 will be described.

  Next, details of each device included in the communication system 1 will be described. The communication terminal 20 is used by the owner (user) of the communication terminal 20 to connect to and communicate with the mobile communication network N1 and transmit data transmitted from the first data server 30 and the second data server 40. It is a terminal used when a user browses by receiving and outputting the data to a monitor or the like. Specifically, for example, it is realized as a device having a communication function such as a mobile phone or a PDA (Personal Digital Assistance) Is done. The receiving terminal 50 is configured by hardware such as a CPU, a memory, a monitor, and a communication module. In the present embodiment, the communication terminal 20 connected to the mobile communication network N1 has been described. However, the communication terminal 20 may not necessarily be portable. Further, a wired network may be used instead of the mobile communication network N1.

  In the present embodiment, a data transmission request (HTTP request) held in the first data server 30 is transmitted from the communication terminal 20 to the data relay apparatus 10 via the mobile communication network N1 by a user operation. The Furthermore, the data transmitted from the first data server 30 via the data relay device 10 based on the data transmission request is received. Then, the object data is received by referring to the link information embedded in the data and transmitting a request for transmitting the object data specified by the link information to the data relay apparatus 10. Thereby, in the communication terminal 20, a series of data including the data transmitted from the 1st data server 30 is acquired, and this series of data is output with respect to a user. The data transmission request and the object data transmission request described above include information for specifying data and information (for example, a domain) for specifying a data server in which the data is stored, and are described by, for example, a URL (Uniform Resource Locator). Information is included.

  The first data server 30 and the second data server 40 are devices that store data to be transmitted to the communication terminal 20. And according to the transmission request transmitted from the communication terminal 20 via the data relay apparatus 10, it has the function to transmit data by communication via the internet N2. Specifically, the first data server 30 and the second data server 40 store document data (web page) described in HTML, object data such as image data used in the web page, and the like. The web server etc. which transmit according to the transmission request from the communication terminal 20 correspond. The data stored in the first data server 30 and the second data server 40 is created and stored by the administrator of each server.

  The data relay device 10 is a device that characterizes the present invention, and receives a transmission request such as a data transmission request and an object data transmission request transmitted from the communication terminal 20 via the mobile communication network N1 as described above. Based on the transmission request, it has a function of acquiring data from servers such as the first data server 30 and the second data server 40 and transmitting the data to the communication terminal 20. The data relay device 10 embeds link information for identifying object data embedded in data acquired from the first data server 30 based on a data transmission request transmitted from the communication terminal 20 and held in the second data server 40. The dummy link information that identifies the first data server 30 is changed and transmitted to the communication terminal 20. Then, the object data transmission request transmitted from the communication terminal 20 is received based on the dummy link information embedded in the data, the object data transmission request is made to the second data server 40, and the second data server 40 The object data is acquired from the communication terminal 20 and transmitted to the communication terminal 20. Details of this process will be described later.

  Here, “dummy link information” will be described. The dummy link information is information newly generated in the data relay device 10 so that the communication terminal 20 can continuously transmit object data transmission requests using request pipelining. As described above, the link information includes information for specifying a data server that holds object data embedded in document data, and information for specifying object data from data held in the data server. However, in order for the communication terminal 20 to transmit an object data transmission request using request pipelining, the data server holding the object data is the same as the data server holding the HTML document data. is necessary. Therefore, in the data relay device 10, it is determined that the information specifying the data server included in the link information to the object data included in the data transmitted from the first data server 30 is different from the first data server 30. In this case, the information specifying the data server is rewritten to information that matches the data transmission source (in this embodiment, the first data server 30), and the dummy link information is generated. Then, it is embedded in the data to be transmitted to the communication terminal 20 instead of the link information and transmitted to the communication terminal 20.

  As shown in FIG. 2, the data relay device 10, the first data server 30, and the second data server 40 include a CPU (Central Processing Unit) 101, a RAM (Random Access Memory) 102 that is a main storage device, and a ROM ( ReadOnly Memory) 103, a communication module 104 for performing communication, and a computer including hardware such as an auxiliary storage device 105 such as a hard disk. And when these components operate, each function of each device 10, 30 and 40 is exhibited.

  Next, functions of each unit constituting the data relay device 10 will be described. As shown in FIG. 1, the data relay apparatus 10 includes a data transmission request receiving unit 11, a data receiving unit 12, a link information conversion processing unit 13, a data transmitting unit 14, a link information storage unit 15, and an object data transmission request receiving unit 16. The object data receiving unit 17 and the object data transmitting unit 18 are included.

  The data transmission request receiving unit 11 functions as a data transmission request receiving unit that receives a data transmission request for requesting data transmission from the first data server 30 transmitted from the communication terminal 20 via the mobile communication network N1. . Specifically, first, based on a communication path establishment request transmitted from the communication terminal 20 to transmit a data transmission request to the data transmission request reception unit 11, the data relay device 10 and the communication terminal 20 A process of providing a communication path (TCP connection) is performed. Thereafter, the data transmission request receiving unit 11 receives a data transmission request transmitted from the communication terminal 20 via the communication path. The data transmission request received by the data transmission request receiving unit 11 is sent to the data receiving unit 12.

  Based on the data transmission request transmitted from the communication terminal 20, the data reception unit 12 transmits the data transmission request to the first data server 30, thereby changing the object data held in the second data server 40. It functions as data receiving means for receiving data embedded with the link information from the first data server 30. Specifically, the first data server 30 holds the data based on information (for example, URL domain) that specifies the storage destination of the data included in the data transmission request transmitted from the communication terminal 20. Check. Next, a request for opening a communication path is transmitted from the data receiving unit 12 to the first data server 30, and processing for providing a communication path between the data relay device 10 and the first data server 30 is performed. Then, using this communication path, a data transmission request specifying the data name is transmitted from the data receiving unit 12 to the first data server 30. Then, data (HTML document) corresponding to the URL transmitted from the first data server 30 based on the transmission request is received. In this data, link information for specifying object data stored in the second data server 40 described by, for example, a URL is embedded. The data received by the data receiving unit 12 is sent to the link information conversion processing unit 13.

  The link information conversion processing unit 13 generates dummy link information to the first data server 30 in association with the link information to the object data held by the second data server 40 embedded in the data, and this dummy link. It functions as link information conversion processing means for embedding information in data instead of the link information. Specifically, the data received by the data receiving unit 12 is parsed, and link information for object data such as image data is extracted. Then, it is determined whether or not the information for specifying the data server that stores the object data included in the link information described by the URL embedded in the data matches the transmission source of the data (first data server 30). Is done. The above determination can be made based on whether or not the data server that is the transmission source of the data matches, for example, data included in the data transmission request from the communication terminal 20 received by the data transmission request receiving unit 11 It can also be determined based on whether or not the information matches the information for specifying the storage destination.

  Here, for example, when a domain indicating the second data server 40 is described, the link information conversion processing unit 13 generates dummy link information in which the domain is rewritten to the first data server 30, and the link By being replaced with information, it is embedded in the data. As a result, the storage location of the object data is converted from the link information indicating the second data server 40 to the dummy link information indicating the first data server 30. The link information for which dummy link information is generated and replaced by the link information conversion processing unit 13 is only link information for object data or the like. For example, the link information for other web pages is replaced. Not done.

  The converted data obtained by converting the link information as described above is sent from the link information conversion processing unit 13 to the data transmission unit 14. The link information embedded in the data transmitted from the first data server 30 and the dummy link information generated in the link information conversion processing unit 13 are sent to the link information storage unit 15.

  The data transmission unit 14 functions as a data transmission unit that transmits the converted data in which the dummy link information is embedded in the link information conversion processing unit 13 to the communication terminal 20 that has transmitted the data transmission request. When the data transmission unit 14 transmits the converted data, the communication terminal 20 receives data corresponding to the data transmission request.

  The link information storage unit 15 stores the link information embedded in the data transmitted from the first data server 30 and the dummy link information generated by the link information conversion processing unit 13 in association with each other. Function as. Information stored in the link information storage unit 15 is used for processing to be described later. The information stored in the link information storage unit 15 is such that the communication terminal 20 provides a communication path (TCP connection) with the first data server 30 and acquires an HTML document (data) from the first data server 30. It is created when the communication path between the communication terminal 20 and the first data server 30 is disconnected.

  The object data transmission request receiving unit 16 is an object data transmission request receiving unit that receives an object data transmission request transmitted from the communication terminal 20 based on the dummy link information embedded in the data transmitted by the data transmitting unit 14. Function. This object data transmission request includes dummy link information embedded in the data transmitted by the data transmission unit 14. The dummy link information includes information indicating that the storage location of the object data is the first data server 30 as described above. Therefore, the object data transmission request receiving unit 16 receives a transmission request for object data stored in the first data server 30 transmitted from the communication terminal 20. The object data transmission request received by the object data transmission request receiving unit 16 is sent to the object data receiving unit 17.

  The object data receiving unit 17 refers to the link information storage unit 15 described above, acquires link information stored in association with the dummy link information included in the object data transmission request, and based on the link information, A request for transmission of object data is made to the data server 40. And it functions as an object data receiving means for acquiring object data transmitted from the second data server 40 based on the transmission request. Specifically, the link information stored in the link information storage unit 15 is acquired in association with the dummy link information included in the object data transmission request. Next, a request for opening a communication path is transmitted from the object data receiving unit 17 to the data server (second data server 40 in this embodiment) specified by the link information, and the data relay device 10 and the second data server. A process of providing a communication path with 40 is performed. Then, using this communication path, an object data transmission request is made from the object data receiving unit 17, and the object data transmitted from the second data server 40 is received. The object data received by the object data receiving unit 17 is sent to the object data transmitting unit 18.

  The object data transmission unit 18 functions as an object data transmission unit that transmits the object data received by the object data reception unit 17 to the communication terminal 20. This object data is transmitted in response to the object data transmission request transmitted from the communication terminal 20. The object data transmission request transmitted from the communication terminal 20 includes dummy link information indicating that object data is stored in the first data server 30 as described above. Therefore, when the object data is transmitted from the object data transmission unit 18 to the communication terminal 20, the object data transmission unit 18 sends the first data from the second data server 40 to the first data as necessary. The server 30 is changed.

  In this manner, each unit included in the data relay device 10 functions as described above, so that a series of data including data transmitted from the first data server 30 is based on the HTTP request transmitted from the communication terminal 20. Data is acquired in the communication terminal 20, and this series of data is output to the user.

  Next, the data relay method by the data relay apparatus 10 will be described with reference to the sequence diagram shown in FIG. Here, the data to which the data transmission request is transmitted by the communication terminal 20 is an HTML document stored in the first data server 30. Three pieces of link information are embedded in the HTML document, and each link information is A data relay method by the data relay device 10 in the case of information indicating image data stored in the second data server 40 will be described.

  In the following description, “www.foobar.com” is used as the domain of the first data server 30, and “cache1.foobar.com” is used as the domain of the second data server 40.

  First, a data transmission request (HTTP request) for an HTML document specified by the file name “index.html” stored in the first data server 30 is transmitted from the communication terminal 20 to the data relay apparatus 10, and the data relay apparatus 10 data transmission request reception units 11 (S01, data transmission request reception step). Specifically, as described above, first, a process for establishing a communication path between the communication terminal 20 and the data relay device 10 is performed, and then a data transmission request is transmitted via this communication path. The processing related to the transmission of the data transmission request is performed by the user of the communication terminal 20 operating the communication terminal 20. Here, as a data transmission request transmitted from the communication terminal 20, the domain and data of the first data server 30 are specified as "Get =" http://www.foobar.com/index.html "". A URL including a file name (index.html) is used. The data transmission request received by the data transmission request receiving unit 11 is sent to the data receiving unit 12, and the data receiving unit 12 performs processing for opening a communication path between the data relay device 10 and the first data server 30. Then, the data reception unit 12 requests the first data server 30 to transmit data (S02, data reception step).

  Next, the data receiving unit 12 receives data transmitted as “Response = index.html” from the first data server 30 based on the data transmission request transmitted from the data relay device 10 (S03, data Reception step), and sent to the link information conversion processing unit 13.

  Here, an example of the data received by the data receiving unit 12 is shown in FIG. In this data relay method, three pieces of link information D10a, D10b, and D10c are embedded in the data D10 (file name: index.html) transmitted from the first data server 30. The link information D10a to c indicates that image data (file names: 001.jpg, 002.jpg, 003.jpg) is stored in the second data server 40 (domain: cache1.foobar.com), respectively. . Although not shown in FIG. 4A, the link information is surrounded by the tag “<imgsrc =“ ”>” so that the link information to the image data is the link information conversion processing unit. 13 is recognized. Further, since the link information is surrounded by the tag, it is determined that the image data is included in the “series of data” including the data D10 that is an HTML document.

  Next, in the link information embedded in the data D10 sent from the data receiving unit 12 to the link information conversion processing unit 13, the link information conversion processing unit 13 generates dummy link information corresponding to each link information, Instead of link information, it is embedded in data D10 (S04: link information conversion processing step). The link information conversion process (S04) by the link information conversion processing unit 13 is performed by the data server that is surrounded by the tags that are known to be link information as described above and that stores the object data specified by the link information. This is performed for link information that is not one data server 30.

  Here, an example of the data D11 after the dummy link information is generated and embedded by the link information conversion processing unit 13 is shown in FIG. In the data relay device 10 of the present embodiment, the dummy link information generated by the link information conversion processing unit 13 changes the domain from the second data server 40 to the first data server 30, and does not change the file name of the image data. Is. Therefore, dummy link information D11a is generated for the link information D10a by replacing the domain of the second data server 40 (cache1.foobar.com) with the domain of the first data server 30 (www.foobar.com), and the link It is embedded instead of the information D10a. Similarly, dummy link information D11b and D11c are respectively generated and embedded in place of the link information D10b and D10c of the data D10 before conversion.

  Further, information in which the link information and the dummy link information are associated with each other is stored in the link information storage unit 15 (link information storage step). FIG. 5 is a diagram illustrating an example of information stored in the link information storage unit 15 in the data relay method according to the present embodiment. As shown in FIG. 5, in the link information storage unit 15, the data URL (http://www.foobar.com/index.html) is used as information for specifying the data (HTML document) in which the link information is embedded. Used. Then, link information (before conversion) included in the data and dummy link information (after conversion) embedded in association with the link information are stored in association with each other.

  After the above processing is performed, the data in which the dummy link information is embedded is sent from the link information conversion processing unit 13 to the data transmission unit 14.

  The data transmission unit 14 acquires the data in which the dummy link information is embedded from the link information conversion processing unit 13, and transmits the data to the communication terminal 20 that has transmitted the data transmission request (S05, data transmission step).

  Subsequently, the object data transmission request (HTTP request) transmitted from the communication terminal 20 that has received the data in which the dummy link information is embedded is received by the object data transmission request receiving unit 16 of the data relay device 10 (S06a to S06a). c, Object data transmission request receiving step). This object data transmission request is made individually for each of the three object data.

  Here, the communication terminal 20 transmits an object data transmission request based on the dummy link information for the first data server 30 embedded in the converted data. That is, for the communication terminal 20, since this object data transmission request is a transmission request to the same data server as the first data server 30 that is the target of the data transmission request (S01), the communication terminal 20 uses request pipelining. 20 is transmitted. Therefore, after transmitting one object data transmission request from the communication terminal 20 and receiving the object data transmitted via the data relay device 10 in response to the object data transmission request, the next object data transmission request is issued. Instead of transmitting, a plurality of object data transmission requests are transmitted simultaneously from the communication terminal 20 (S06a-c). The object data transmission request from the communication terminal 20 is transmitted as dummy link information to the communication terminal 20 as “Get =” http://www.foobar.com/001.jpg ”(S06a). The URL of the object data is used. The object data transmission request received by the object data transmission request receiving unit 16 is sent to the object data receiving unit 17.

  The object data receiving unit 17 refers to the information stored in the link information storage unit 15 for each object data transmission request received by the object data transmission request receiving unit 16 and associates it with each dummy link information. The link information stored is acquired (S07, object data receiving step). For example, the URL “http: of the dummy link information (after conversion) included in the object data transmission request“ Get = ”http://www.foobar.com/001.jpg” (S06a) transmitted from the communication terminal 20 In contrast to “//www.foobar.com/001.jpg”, the URL “http://cache1.foobar.com/001.jpg” of link information before conversion is stored in the table shown in FIG. The object data receiving unit 17 confirms that the URL is link information before conversion. The object data receiving unit 17 also refers to the information stored in the link information storage unit 15 for other object data transmission requests (S06b, S06c) received by the communication terminal 20, and sends an object data transmission request. The link information associated with the dummy link information indicated in the URL included in is confirmed.

  Next, the object data receiving unit 17 performs processing for providing a communication path between the data relay device 10 and the second data server 40 based on the link information confirmed above, and then uses this communication path. Then, transmission of object data is requested to the second data server 40 (S08a-c, object data receiving step). Specifically, for example, when the link information URL “http://www.foobar.com/001.jpg” is confirmed in the confirmation of the link information (S07), the object using the URL is used. A data transmission request “Get =“ http://cache1.foobar.com/001.jpg ”” (S08a) is transmitted from the object data receiving unit 17 to the second data server 40. The object data transmission request from the object data receiving unit 17 to the second data server 40 is also based on another object data transmission request received from the communication terminal 20 and whose link information is confirmed by the object data receiving unit 17. Is transmitted (S08b, S08c).

  The object data reception unit 17 receives object data transmitted from the second data server 40 based on these object data transmission requests (S09a to c, object data reception step). For example, the object data transmission request (S08a) indicated by the file name “001.jpg” transmitted by the object data receiving unit 17 is handled as “Response = 001.jpg” from the second data server 40. Since the object data to be transmitted is transmitted, the object data receiving unit 17 receives the object data. Similarly, in response to other object data transmission requests (S08b, S08c), the object data is transmitted from the second data server 40, and the object data receiving unit 17 receives them (S09b, S09c). The object data received by the object data receiving unit 17 is sent to the object data transmitting unit 18.

  Then, in the object data transmission unit 18, the object data transmitted from the object data reception unit 17 is transmitted to the communication terminal 20 (S10a to c, object data transmission step). Here, the object data transmitted from the object data transmission unit 18 to the communication terminal 20 is transmitted from the second data server 40 as described above (S09a to Sc), but is transmitted from the communication terminal 20. The object data transmission request (S06a to c) is for the first data server 30. Therefore, the communication terminal 20 recognizes that the object data transmitted to the communication terminal 20 is the object data transmitted from the data relay device 10 in response to the object data transmission request transmitted from the communication terminal 20. As described above, the object data transmission unit 18 rewrites the transmission source of the object data to the first data server 30 as necessary.

  Through the above processing, the communication terminal 20 acquires a series of data including an HTML document (index.html) and object data (001.jpg, 002.jpg, 003.jpg) embedded in the HTML document. Then, by outputting the series of data to a monitor or the like, the user of the communication terminal 20 can browse the series of data. Thereby, the process concerning the data relay method according to the present embodiment is completed.

  In the above processing, the data relay device 10 and the communication terminal 20 are opened, the data relay device 10 and the first data server 30, and the data relay device 10 and the second data server 40, respectively. When the use of the communication path is finished, the communication path disconnection process is performed by transmitting a communication path disconnection request from the apparatus that has requested the establishment of the communication path. Specifically, a communication path disconnection request between the data relay apparatus 10 and the communication terminal 20 is transmitted to the data relay apparatus 10 from the communication terminal 20 that transmitted the communication path establishment request. Similarly, a request for disconnecting the communication path between the data relay apparatus 10 and the first data server 30 and the communication path between the data relay apparatus 10 and the second data server 40 is transmitted by the data relay apparatus 10.

  The effects of the data relay apparatus 10 and the data relay method by the data relay apparatus 10 according to the above-described embodiment will be described.

  First, a conventional method in which the communication terminal 20 acquires a series of data by request pipelining will be described. Conventionally, when the communication terminal 20 acquires a series of data including an HTML document, first, after receiving the HTML document, the link information embedded is acquired by performing syntax analysis. Subsequently, using the link information, an object data transmission request is transmitted for each object data, and the object data is acquired. Here, when the communication terminal 20 transmits an object data transmission request (HTTP request) related to object data included in an HTML document, the request is continuously performed without waiting for completion of acquisition of object data corresponding to the HTTP request by request pipelining. Can be sent to the data server. On the other hand, on the data server side, object data is continuously transmitted with respect to HTTP transmitted continuously. Thereby, the reception of the object data in the communication terminal 20 is performed at high speed.

  However, in order to perform request pipelining as described above, it is necessary to use a persistent connection provided with the data server. Since this persistent connection is provided with the data server when the communication terminal 20 acquires the HTML document, for example, as in the present embodiment, the HTML document is held in the first data server 30, and the HTML When the object data included in the document is stored in the second data server 40, it is necessary to provide a new communication path (TCP connection) with the second data server 40 when acquiring the object data. Persistent connection is not available. Therefore, there is a problem that request pipelining cannot be performed and a series of data cannot be efficiently acquired in the communication terminal 20.

  In the present embodiment, the above problem is solved by replacing the link information for the second data server 40 with the dummy link information for the first data server 30 in the data relay device 10. That is, by converting the information regarding the object data included in the HTML document (data) received at the communication terminal 20 into the dummy link information for the first data server 30 in the link information conversion processing unit 13 of the data relay device 10, The communication terminal 20 recognizes that the object data is held in the first data server 30. For this reason, it is recognized that the communication terminal 20 can use request pipelining by continuously using the persistent connection provided with the first data server 30. Thereby, the object data transmission request can be transmitted continuously from the communication terminal 20.

  Further, according to the present embodiment, the link information storage unit 15 of the data relay device 10 stores information in which link information and dummy link information are associated with each other. Thereby, in response to the object data transmission request (for the first data server 30) based on the dummy link information from the communication terminal 20, the object data is acquired by requesting the second data server 40 to transmit the object data. It can be transmitted to the communication terminal 20. Therefore, the data relay device 10 acquires object data from an appropriate data server (in this embodiment, the second data server 40) in response to an object data transmission request transmitted from the communication terminal 20 based on the dummy link information. Then, it can be transmitted to the communication terminal 20.

  As described above, according to the present embodiment, a series of data stored in a plurality of servers can be quickly received by the communication terminal 20, and can be output to the user more quickly. In addition, this effect is more effectively exhibited when the data relay apparatus 10 communicates with the communication terminal 20 and the data server (the first data server 30 and the second data server 40) using HTTP. The

  The preferred embodiments of the present invention have been described above. However, the data relay device and the data relay method according to the present invention are not limited to the above embodiments, and can take various forms. .

  For example, in the above-described embodiment, a mode in which the communication terminal 20 communicates with the mobile communication network N1 has been described. The present invention can also be applied to other communication networks that perform communication via a relay device.

  In the above embodiment, only the second data server 40 is shown as a server for storing object data. However, object data included in one HTML document is distributed and stored in a plurality of data servers. May be. Even in this case, a series of data distributed and held in a plurality of servers can be obtained by embedding dummy link information in an HTML document instead of link information for object data by the same processing as in this embodiment. The same effect as the above-described embodiment that the communication terminal receives quickly can be obtained.

  Further, when the link information conversion processing unit 13 generates dummy link information from the link information included in the data, the dummy data is stored in the first data server 30 in the storage location of the object data specified in the dummy link information. However, various changes can be made. For example, when the link information is described by a URL, the domain is converted to the first data server 30 to generate dummy link information, and the domain is converted to the first data server 30 and the file name of the object data is aliased. The dummy link information changed to may be generated. It is preferable that the method for generating the dummy link information is determined in advance by an administrator of the data relay apparatus 10 or the like.

  In the above embodiment, another HTML document (web page) specified by the link information described in the data of the HTML document is a target in which dummy link information is generated by the link information conversion processing unit 13 and embedded in the data. Although it is described that this is not the case, dummy link information can also be embedded as link information for other HTML documents. That is, for example, the link information conversion processing unit 13 generates and embeds dummy link information for link information to other HTML documents (web pages) described by being enclosed in the tag “<a href=“”>”. Can do. In this case, it is possible to obtain the same effect as in the above-described embodiment in which the communication terminal 20 receives a series of data held in a plurality of servers quickly, and communication necessary for acquiring the other HTML document. Since the process of establishing a path (TCP connection) can be omitted, communication performed for establishing a new communication path between the communication terminal 20 and the data relay device 10 can be reduced. A further effect is obtained that the communication terminal can quickly receive the HTML document.

It is a figure which shows the structure of the communication control system containing the data relay apparatus which concerns on suitable embodiment of this invention, and those connection relations. It is a figure which shows the hardware constitutions of the data relay apparatus, 1st data server, and 2nd data server in embodiment of this invention. It is a sequence diagram explaining the data relay method in the communication control system containing the data relay apparatus which concerns on embodiment of this invention. It is a figure which shows the example of the data received by the data receiving part of the data relay apparatus, and the example by which dummy link information was embedded with respect to this data by the link information conversion process part. It is a figure which shows the example of the information stored in the link information storage part of a data relay apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Communication system, 10 ... Data relay apparatus, 20 ... Communication terminal, 30 ... 1st data server, 40 ... 2nd data server.

Claims (3)

A data relay device that transmits data transmitted from a plurality of data servers to a communication terminal that communicates by connecting to a communication network,
A data transmission request receiving means for receiving a data transmission request for requesting transmission of data from the first data server, transmitted from the communication terminal;
By transmitting the data transmission request to the first data server based on the data transmission request, the data in which the link information to the object data held by the second data server is embedded is stored in the first data server. Data receiving means for receiving from one data server;
Dummy link information to the first data server is generated in association with the link information to the object data held by the second data server embedded in the data, and the dummy link information is replaced with the link information. Link information conversion processing means embedded in the data;
Data transmitting means for transmitting the data in which the dummy link information is embedded by the link information conversion processing means to the communication terminal;
Link information storage means for holding the link information embedded in the data and the dummy link information generated by the link information conversion processing means in association with each other;
Object data transmitted from the communication terminal based on the dummy link information embedded in the data and receiving an object data transmission request for requesting transmission of object data from the first data server including the dummy link information A transmission request receiving means;
Based on the link information associated with the dummy link information included in the data transmission request stored in the link information storage means, a transmission request for object data data is transmitted to the second data server. An object data receiving means for receiving object data transmitted from the second data server;
Object data transmitting means for transmitting the object data received by the object data receiving means to the communication terminal;
A data relay device comprising:   The data relay apparatus according to claim 1, wherein transmission / reception is performed using HTTP with the communication terminal, the first server, and the second server. A data relay method by a data relay apparatus that transmits data transmitted from a plurality of data servers to a communication terminal that communicates by connecting to a communication network, and includes a link information storage unit,
A data transmission request receiving step for receiving a data transmission request for requesting transmission of data from the first data server, transmitted from the communication terminal;
By transmitting the data transmission request to the first data server based on the transmission request, the data in which the link information to the object data held by the second data server is embedded is stored in the first data server. A data receiving step for receiving data from the data server;
Dummy link information to the first data server is generated in association with the link information to the object data held by the second data server embedded in the data, and the dummy link information is replaced with the link information. Link information conversion processing step embedded in the data;
A data transmission step of transmitting the data in which the dummy link information is embedded in the link information conversion processing step to the communication terminal;
A link information storage step of associating the link information embedded in the data with the dummy link information generated in the link information conversion processing step and holding it in a link information storage means;
Object data transmitted from the communication terminal based on the dummy link information embedded in the data and receiving an object data transmission request for requesting transmission of object data from the first data server including the dummy link information A transmission request reception step;
Transmitting an object data transmission request to the second data server based on the link information associated with the dummy link information included in the data transmission request stored in the link information storage means; An object data receiving step for receiving object data transmitted from the second data server;
An object data transmission step of transmitting the object data received in the object data reception step to the communication terminal;
A data relay method comprising:

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