Abstract:
A server includes: a receiving device configured to acquire page contents requested by a predetermined client terminal among multiple client terminals; multiple information generation devices each of which includes a conversion device configured to convert the acquired page contents to an image and a UI information metadata generating device configured to extract UI information from the acquired page contents and to generate UI information metadata on the basis of the extracted UI information; a session management device configured to, upon receiving the request from the predetermined client terminal, issue a session ID for identifying the predetermined client terminal and to manage the issued session ID and a desired information generation device among the multiple information generation devices in association with each other; and a transmission device configured to transmit the converted image, the generated UI information metadata and the issued session ID to the predetermined client terminal.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The presently disclosed subject matter relates to a website browsing system and a server, and in particular to a website browsing system for browsing and operating a website for PCs (personal computers) on such a client terminal that the screen size and the downloadable file size are restricted, such as a mobile phone, and a server. 
         [0003]    2. Description of the Related Art 
         [0004]    Recently, there are a lot of occasions of browsing a website by a mobile phone. However, since it costs much and is very troublesome to create a website for mobile phones in addition to a website for PCs, a site creator has a tendency to avoid creation of a website for mobile phones. Therefore, it is often the case that a site for mobile phones is not prepared at a website which a user wants to browse. 
         [0005]    In the case of browsing a website for PCs on a mobile phone inferior to a PC in the image size and the downloadable file size, it is conceivable to receive a contents file being divided and display the contents file as multiple pages. However, when browsing the webpage on a PC and browsing the webpage on a mobile phone are compared, difference in appearance occurs. 
         [0006]    Conversion to a markup language for mobile phones is also conceivable. However, a design deformation problem tends to occur. 
         [0007]    To cope with this problem, there is proposed a method of converting a website for PCs to an image to display it on a mobile phone. For example, in Japan Patent Application Laid-Open No. 2004-220260, a webpage is constructed of components of an HTML (HyperText Markup Language) document or the like of a webpage acquired on an image distribution server, and the created webpage is converted to bitmap image data or the like and transmitted to a client terminal. When the user of the client terminal on which this image data is displayed clicks a displayed character string or the like using a pointing device, the client terminal transmits coordinates data of the clicked position and the URL of the displayed webpage to the image distribution server. The image distribution server checks whether or not a link pointer corresponding to the transmitted click position coordinates exists on the basis of the components of the webpage, and accesses a web server specified by a URL indicated by the link pointer if the link pointer exists. 
         [0008]    According to the technique of Japan Patent Application Laid-Open No. 2004-220260, it is possible even for a client terminal which is not implemented with a web browser to browse a webpage. 
       SUMMARY OF THE INVENTION 
       [0009]    In the technique described in Japan Patent Application Laid-Open No. 2004-220260, it is possible to utilize a link pointer (a link tag in HTML) in a webpage and display a link destination corresponding to a position clicked by a user. However, input forms other than link tags, such as a text input field and a checkbox, may not be utilized. Thus, in Japan Patent Application Laid-Open No. 2004-220260, there is a problem that all user interface (UI) information in an webpage may not be utilized. 
         [0010]    Furthermore, since communication with a server is performed each time a user operation occurs, there is a problem that the load on the server is high, and furthermore, there is a problem that much communication time is required. 
         [0011]    The presently disclosed subject matter has been made in view of the above situation, and its object is to provide a website browsing system making it possible to browse and operate different webpages for PCs using multiple mobile phones or the like, and a server. 
         [0012]    In order to achieve the above object, a first aspect of the presently disclosed subject matter provides A website browsing system in which multiple client terminals connect to a server, wherein the server includes: a first receiving device configured to acquire page contents requested by a predetermined client terminal among the multiple client terminals; multiple information generation devices each of which includes a conversion device configured to convert the acquired page contents to an image and a UI information metadata generating device configured to extract UI information from the acquired page contents and to generate UI information metadata on the basis of the extracted UI information; a session management device configured to, upon receiving the request from the predetermined client terminal, issue a session ID for identifying the predetermined client terminal and to manage the issued session ID and a desired information generation device among the multiple information generation devices in association with each other; and a first transmission device configured to transmit the converted image, the generated UI information metadata and the issued session ID to the predetermined client terminal, and the client terminal includes: a second transmission device configured to request desired page contents from the server; a second receiving device configured to receive the image of the requested page contents, the UI information metadata and the session ID which have been transmitted from the server; a display device configured to display the image on the basis of the received image and UI information metadata; and a display control device configured to display the received image on the display device and to display the UI information on the image on the basis of the UI information metadata. 
         [0013]    According to the first aspect, when page contents are requested by a predetermined client terminal among multiple client terminals, a session ID for identifying the predetermined client terminal is issued, and the session ID and a desired information generation device among multiple information generation devices are managed in association with each other. The page contents acquired by the predetermined information generation device associated with the session ID is converted to an image, and UI information metadata is generated. The image, the UI information metadata and the session ID are transmitted to the client terminal. The client terminal which receives them displays the image on the display device and displays UI information on the image on the basis of the UI information metadata. Thereby, it is possible to browse and operate a webpage for PCs at a high speed using a mobile phone or the like without deforming the design of the webpages. Furthermore, it is possible to enable each of multiple client terminals to browse and operate a webpage corresponding to the request of the client terminal. 
         [0014]    A second aspect of the presently disclosed subject matter provides a website browsing system according to the first aspect, wherein, when the first receiving device receives a request from a client terminal other than the predetermined client terminal, among the multiple client terminals, the session management device generates a session ID for identifying the client terminal other than the predetermined client terminal, which is a session ID different from the session ID for identifying the predetermined client terminal, and manages the generated session ID and an information generation device which is not associated with a session ID among the multiple information generation devices in association with each other. 
         [0015]    According to the second aspect, when a request from a client terminal other than a predetermined client terminal is received, a session ID for identifying the client terminal other than the predetermined client terminal, which is a session ID different from a session ID for identifying the predetermined client terminal is generated. Then, the generated session ID and an information generation device which is not associated with a session ID yet are managed in association with each other. Thereby, it is possible to perform different processing for a request from a different client terminal. 
         [0016]    A third aspect of the presently disclosed subject matter provides a website browsing system according to the first or second aspect, wherein the second transmission device transmits information indicating the client terminal to the server; the first receiving device receives the information indicating the client terminal; and the session management device determines whether or not the client terminal is a mobile terminal on the basis of the information indicating the client terminal, and does not generate a session ID if it is determined that the client terminal is not a mobile terminal. 
         [0017]    According to the third aspect, information indicating a client terminal is received from the client terminal, and it is determined whether or not the client terminal is a mobile terminal on the basis of this information. A session ID is not issued if the client terminal is not a mobile terminal, and a session ID is issued if the client terminal is a mobile terminal. Therefore, it is possible to generate an image or UI information when generation of the image or the UI information is necessary. 
         [0018]    A fourth aspect of the presently disclosed subject matter provides a website browsing system according to the first or second aspect, wherein the client terminal further includes a user ID storage device in which information indicating a client terminal and a user ID are stored in association with each other, the second transmission device transmits the information indicating the client terminal to the server, the first receiving device receives the information indicating the client terminal, and the session management device determines whether or not the received information indicating the client terminal is stored in the user ID storage device, and generates a session ID if it is determined that the information is stored in the user ID storage device. 
         [0019]    According to the fourth aspect, information indicating a client terminal and a user ID are stored in association with each other. A session ID is generated if information indicating a client terminal transmitted from the client terminal is stored. Thereby, it is possible to provide an authentication function for the website browsing system. 
         [0020]    A fifth aspect of the presently disclosed subject matter provides a website browsing system according to any of the first to fourth aspects, wherein the client terminal includes: an execution device configured to execute the UI information on the image displayed on the display device; and a rewriting device configured to rewrite the UI information metadata on the basis of the UI information executed by the execution device, and wherein the second transmission device transmits the rewritten UI information metadata to the server together with the session ID, the first receiving device receives the rewritten UI information metadata which has been transmitted from the client terminal together with the session ID, the information generation device associated with the received session ID rewrites the image on the basis of the received UI information metadata, and the first transmission device transmits the rewritten image to the client terminal together with the session ID. 
         [0021]    According to the fifth aspect, when UI information on an image displayed on a client terminal is executed, UI information metadata is rewritten and transmitted to a server together with a session ID. An information generation device associated with the session ID rewrites the image on the basis of the UI information metadata, and the rewritten image is transmitted to the client terminal together with the session ID. Thereby, it is possible to display an image according to an operation of executed UI information. Furthermore, since UI information metadata is transmitted together with a session ID, it is possible to certainly recognize on which client terminal the operation has been performed and prevent the image from being wrongly transmitted to a different client terminal. 
         [0022]    A sixth aspect of the presently disclosed subject matter provides a website browsing system according to the fifth aspect, wherein, if the UI information executed by the execution device is UI information accompanied by screen transition, the second transmission device transmits information identifying the UI information to the server together with the session ID, the first receiving device receives the information identifying the UI information and the session ID which have been transmitted from the second transmission device, the information generation device associated with the received session ID generates an image of page contents to be displayed next and UI information metadata of the page contents on the basis of the received information, and the first transmission device transmits the image of the page contents to be displayed next and the UI information metadata of the page contents which have been generated, to the client terminal. 
         [0023]    According to the sixth aspect, when UI information accompanied by screen transition is executed, information identifying the UI information is transmitted to the server together with a session ID. An information generation device associated with the session ID generates an image of page contents to be displayed next and UI information metadata of the page contents on the basis of the information identifying the UI information, and the generated image and UI information metadata are transmitted to the client terminal with a session ID. Thereby, it is possible to, when UI information accompanied by screen transition is executed, appropriately display an image to be displayed next. Furthermore, since information identifying UI information is transmitted together with a session ID, it is possible to certainly recognize on which client terminal the operation has been performed and prevent the image from being wrongly transmitted to a different client terminal. 
         [0024]    A seventh aspect of the presently disclosed subject matter provides a website browsing system according to the fifth or sixth aspect, wherein the execution device further includes: a movement device configured relatively to move a cursor and an image displayed on the display device; and a decision device configured to decide UI information existing at a position overlapping a position of the cursor as UI information to be executed. 
         [0025]    Thereby, it is possible to appropriately select UI information to be executed. 
         [0026]    An eighth aspect of the presently disclosed subject matter provides a website browsing system according to the seventh aspect, wherein the movement device moves the cursor relative to the image displayed on the display device. 
         [0027]    Thereby, it is possible to appropriately select UI information to be executed. 
         [0028]    A ninth aspect of the presently disclosed subject matter provides a website browsing system according to the seventh aspect, wherein the movement device displays the cursor almost in the center of the display device and moves the image relative to the cursor. 
         [0029]    Thereby, it is possible to appropriately select UI information to be executed. 
         [0030]    A tenth aspect of the presently disclosed subject matter provides a website browsing system according to any of the first to ninth aspects, wherein the movement device displays a visual effect on the basis of the UI information metadata. 
         [0031]    Therefore, it is possible to improve the operability. 
         [0032]    An eleventh aspect of the presently disclosed subject matter provides a website browsing system according to any of the first to tenth aspects, wherein the server includes a storage device in which page contents are stored; and the first receiving device configured to acquire page contents acquires the page contents from the storage device. 
         [0033]    Thereby, communication with an external apparatus is not required to acquire a contents file, and it is possible to realize high-speed and user-friendly webpage browsing. 
         [0034]    A twelfth aspect of the presently disclosed subject matter provides a website browsing system according to any of the first to eleventh aspects, wherein the server includes a connecting device configured to connect to a web server; and the first receiving device configured to acquire page contents acquires the page contents from the web server via the connecting device configured to connect to the web server. 
         [0035]    Thereby, it is possible to browse various webpages. Furthermore, it is possible to browse a contents file which is not stored in the server. 
         [0036]    A thirteenth aspect of the presently disclosed subject matter provides a server constituting the website browsing system according to any of the first to twelfth aspects. 
         [0037]    According to the presently disclosed subject matter, it is possible to browse and operate different webpages for PCs using multiple mobile phones and the like without deforming the design of the webpages. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0038]      FIG. 1  is a diagram illustrating that a webpage for PCs is browsed on a display section  2  of a PC  1  and a display section  14  of a mobile terminal  10 ; 
           [0039]      FIG. 2  is a diagram illustrating an example of the whole configuration of a webpage browsing system  100 ; 
           [0040]      FIG. 3A  is a flowchart illustrating an operation performed before a desired webpage is displayed on the display section  14  of the mobile terminal  10  in the webpage browsing system  100 , and  FIG. 3B  is a flowchart illustrating an operation performed until a desired webpage is displayed on a display section  24  of a PC  20  in the webpage browsing system  100 ; 
           [0041]      FIGS. 4A ,  4 B and  4 C are diagrams for illustrating generation of UI metadata; 
           [0042]      FIG. 5  is a diagram illustrating metadata stored as a CSV (comma separated value) file; 
           [0043]      FIGS. 6A and 6B  are flowcharts illustrating an internal process of the mobile terminal  10  in the webpage browsing system  100 ; 
           [0044]      FIGS. 7A and 7B  are diagrams illustrating the case where a cursor moves in response to an operation; 
           [0045]      FIGS. 8A and 8B  are diagrams illustrating the case where an image moves in response to an operation; 
           [0046]      FIG. 9  is a diagram illustrating enlargement and reduction of an image displayed on the display section  14 ; 
           [0047]      FIGS. 10A ,  10 B,  10 C and  10 D are diagrams for illustrating rewriting of UI metadata; 
           [0048]      FIGS. 11A ,  11 B, and  11 C are diagrams for illustrating rewriting of UI metadata; 
           [0049]      FIG. 12  is a flowchart illustrating an operation performed when a UI operation is performed on the mobile terminal  10  in the webpage browsing system  100 ; 
           [0050]      FIG. 13  is a diagram illustrating an example of the whole configuration of a webpage browsing system  101 ; 
           [0051]      FIG. 14  is a flowchart illustrating an operation performed before a desired webpage is displayed on the display section  14  of the mobile terminal  10  in the webpage browsing system  101 ; 
           [0052]      FIG. 15  is a flowchart illustrating an operation performed when a UI operation is performed on the mobile terminal  10  in the webpage browsing system  101 ; 
           [0053]      FIGS. 16A and 16B  are flowcharts illustrating an internal process of the mobile terminal  10 ; 
           [0054]      FIGS. 17A and 17B  are flowcharts illustrating an internal process of the mobile terminal  10 ; and 
           [0055]      FIG. 18  is a diagram illustrating that the cursor is attracted to UI information. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0056]    Embodiments for practicing the presently disclosed subject matter will be described below with reference to accompanying drawings. 
         [0057]      FIG. 1  is a diagram illustrating an image of browsing a webpage using a display section  14  of a mobile terminal  10  just like browsing the webpage using a display section  2  of a PC  1 . As illustrated in  FIG. 1 , the mobile phone according to the presently disclosed subject matter is capable of browsing a webpage similarly to a PC. 
       First embodiment  
       [0058]      FIG. 2  is a diagram illustrating an example of the whole configuration of a webpage browsing system  100  in this embodiment. As illustrated in  FIG. 2 , the webpage browsing system  100  includes multiple mobile terminals  10  and multiple PCs  20  used by users, and an integrated web server (hereinafter referred to as an integrated server)  30  which includes the function of a relay server for communicating with the mobile terminals  10  and the PCs  20  to perform relay between the mobiles terminals  10  and PCs  20  and a web server and the function of a web server. 
         [0059]    The mobile terminal  10  includes a communication section  11 , a processing section  12 , an input device  13  and a display section  14 . 
         [0060]    The communication section  11  controls communication with the integrated server  30  by predetermined protocols. 
         [0061]    The mobile terminal  10  and the integrated server  30  are connected via the so-called Internet, and each of the communication section  11  and a communication section  31  to be described later performs communication in accordance with standard Internet protocols such as TCP/IP (Transmission Control Protocol/Internet Protocol). They may be connected via a dedicated communication line or a VPN (Virtual Private Network). 
         [0062]    The processing section  12  causes an image acquired from the integrated server  30  via the communication section  11  to be displayed on the display section  14 , and performs processing based on an input operation via the input device  13  by a user. 
         [0063]    The input device  13  includes a power source button, number keys, a cross key, a decision key and the like (not illustrated), and the user can operate the mobile terminal  10  by operating the input device  13 . A touch panel may be arranged on the front surface of the display section  14  to be used as the input device  13 . 
         [0064]    The display section  14  is a liquid crystal display capable of color display, and performs display on the basis of an image signal inputted from the processing section  12 . A display device of another type, such as an organic EL (electroluminescence) display, may be used. 
         [0065]    The PC  20  includes a communication section  21 , a processing section  22 , an input device  23  and a display section  24 . The PC  20  is such that is already well known. Since the functions of the sections constituting the PC  20  are similar to those of the mobile terminal  10 , description thereof will be omitted. 
         [0066]    The integrated server  30  includes a communication section  31 , a web contents storage area  32 , multiple information-for-mobile-terminal generation sections  33  (each of which includes an image conversion section  33 A and a UI information analysis section  33 B), an authentication section  34  and a session DB (database)  35 . The communication section  31  controls communication with the mobile terminal  10 . 
         [0067]    The web contents storage area  32  stores a contents file of each webpage. 
         [0068]    There exist the same number of information-for-mobile-terminal generation sections  33  as the number of session IDs issued by the authentication section  34  to be described later. The information-for-mobile-terminal generation section  33  includes the image conversion section  33 A and the UI information analysis section  33 B. 
         [0069]    On the basis of page contents (a contents file), the image conversion section  33 A generates an image file similarly to the state at the time when the contents file is browsed. Here, the image file is generated with a predetermined resolution. However, an image file with a resolution corresponding to the contents of the contents file or corresponding to the resolution of the mobile terminal  10  may be generated. 
         [0070]    The UI information analysis section  33 B analyzes the contents file and extracts UI information. The UI information analysis section  33 B extracts the UI information from the contents file and analyzes the kind and the position to generate UI metadata. 
         [0071]    The authentication section  34  determines which of a mobile terminal  10  and a PC  20  the counterpart connected to the communication section  31  is. When a mobile terminal  10  or a PC  20  starts communication with the communication section  31  (at the time of access), information indicating the mobile terminal  10  is sent from the mobile terminal  10 , and information indicating the PC  20  is sent from the PC  20 . Therefore, the authentication section  34  can make the determination on the basis of the information. As an example of the information indicating the mobile terminal  10  and the information indicating the PC  20 , a user agent is given. 
         [0072]    If it is determined that the counterpart connected to the communication section  31  is a mobile terminal  10 , the authentication section  34  issues a session ID. Then, the authentication section  34  associates one of the multiple information-for-mobile-terminal generation sections  33  with the issued session ID and stores information about the association into the session DB  35  to perform session management. Thereby, separate communication can be made with each of the multiple mobile terminals  10 . 
         [0073]    If the mobile terminal  10  does not access for a predetermined time or more after the session ID is issued, the authentication section  34  ends the session and deletes the data about the session ID stored in the session DB  35 . Thereby, it becomes possible to issue the session ID when another mobile terminal  10  or the like accesses. 
         [0074]    It was described that the integrated server  30  of this embodiment has multiple information-for-mobile-terminal generation sections  33 . This concept includes the case where there are multiple information-for-mobile-terminal generation sections  33 , the case where there is one information-for-mobile-terminal generation section  33  in which each of the image conversion section  33 A and the UI information analysis section  33 B is divided in multiple areas, and the like. In the case where there are multiple information-for-mobile-terminal generation sections  33 , an information-for-mobile-terminal generation section  33  is associated with a session ID. In the case where each of one image conversion section  33 A and one UI information analysis section  33 B is divided in multiple areas, one predetermined area of the image conversion section  33 A and one predetermined area of the UI information analysis section  33 B are associated with a session ID. 
         [0075]    Next, the operation of the webpage browsing system  100  configured as described above will be described. First, the operation performed before a desired webpage is displayed on the display section  14  of the mobile terminal  10  will be described with reference to  FIG. 3A . 
         [0076]    A user inputs the URL (Uniform Resource Locator) address of a webpage which he wants to browse, using the input device  13  of the mobile terminal  10 . A URL address may be selected with the use of a bookmark or the like registered with a storage section (not illustrated) of the mobile terminal  10  instead of directly inputting a character string. When the user instructs transmission by a transmission button of the input device  13  after inputting the URL address, the communication section  11  transmits the inputted URL address to the integrated server  30  (step S 11 ). 
         [0077]    It is also possible to hold webpage titles and URL addresses as bookmarks in a storage section (not illustrated) of the integrated server  30  so that a webpage title can be selected from among the webpage titles. In this case, the integrated server  30  transmits the webpage titles which it holds to the mobile terminal  10  via the communication section  31 , and the mobile terminal  10  receives them via the communication section  11 . Furthermore, the received webpage titles are displayed on the display section  14  by the processing section  12 . The user selects a desired webpage from among the displayed webpage titles using the input device  13 . Then, the mobile terminal  10  can transmit the selected webpage title to the integrated server  30  via the communication section  11 . 
         [0078]    At step S 11 , the mobile terminal  10  transmits information indicating the mobile terminal  10  to the integrated server  30  together with the URL address. The information indicating the mobile terminal  10  is a user agent here, which is information including information indicating a carrier (“Carrier 1”, “ Carrier 2”, “ Carrier 3” and the like) and information indicating the model of the mobile terminal  10  (hereinafter referred to as a model name). 
         [0079]    The integrated server  30  receives the URL address and the user agent transmitted from the mobile terminal  10  via the communication section  31  (step S 21 ). The authentication section  34  receives the user agent via the communication section  31 . The authentication section  34  analyzes the user agent, and issues a session ID if it recognizes that the access is from the mobile terminal  10  (step S 22 ). Then, a desired one of the multiple information-for-mobile-terminal generation sections  33  (hereinafter referred to as an information-for-mobile-terminal generation section  33 −1) is assigned to the session ID, and the session ID, the information-for-mobile-terminal generation section  33 −1 and the user agent are stored into the session DB in association with one another (step S 23 ). 
         [0080]    An image conversion section (hereinafter referred to as an image conversion section  33 A−1) of the information-for-mobile-terminal generation section  33 −1 acquires a contents file, such as an HTML file, a CSS (cascading style sheets) file and a Java Script file, corresponding to the received URL address from the web contents storage area  32  (step S 24 ). 
         [0081]    A UI information analysis section (hereinafter referred to as a UI information analysis section  33 B−1) of the information-for-mobile-terminal generation section  33 −1 acquires the same contents file as the image conversion section  33 A−1 has acquired, from the web contents storage area  32 , and it analyzes the acquired contents file and extracts UI information (step S 25 ). The contents file analysis method here is not especially limited, and a well-known method, such as a method of extracting a tag by parsing, may be used. 
         [0082]    The UI information analysis section  33 B generates UI metadata on the basis of the result of this analysis (step S 26 ).  FIGS. 4A ,  4 B and  4 C are diagrams for illustrating of generation of the UI metadata.  FIG. 4A  is a diagram illustrating the state in which the HTML file illustrated in  FIG. 4B  has been browsed with the use of a PC or the like. In the HTML file illustrated in  FIG. 4B , unnecessary parts are appropriately omitted. 
         [0083]    The UI information analysis section  33 B−1 extracts UI information such as a link tag and an input form, from the HTML file illustrated in  FIG. 4B  and calculates position coordinates in  FIG. 4A  of each UI information. 
         [0084]    For example, in the HTML file illustrated in  FIG. 4B , six tags, that is, a text input field tag  301 , a radio button tag  302 , a radio button tag  303 , a link tag  304 , a link tag  305  and a button tag  306  are illustrated. The UI information analysis section  33 B extracts pieces of UI information  201  to  206  by extracting these tags from the HTML file. 
         [0085]    The pieces of UI information  201  to  206  are arranged on positions on the screen illustrated in  FIG. 4A  in a state that the HTML is browsed. The UI information analysis section  33 B−1 acquires XY coordinate values (coordinate values corresponding to the upper left and the lower right) indicating the start and end of these pieces of UI information. The coordinate value acquisition method is not especially limited. For example, methods such as storage during image rendering and acquisition from a browser may be used. 
         [0086]    Each of the pieces of UI information and the position information about it which have been extracted as described above are associated with each other together with each UI information ID and stored into the session DB  35  as UI metadata in association with a session ID. Here, the UI information IDs are assumed to be  201  to  206 .  FIG. 5  is a diagram illustrating the UI metadata stored as a CSV file. Attributes (for example, a size attribute) related to screen display, such as layout, need not be included in the UI metadata. 
         [0087]    The image conversion section  33 A−1 performs rendering of the acquired contents file and generates an image file in a format which can be displayed on the display section  14  of the mobile terminal  10 , such as a JPEG (Joint Photographic Experts Group) format and a bitmap format (step S 26 ). The image file generation method is not limited. The image file generation can be performed in a well-known method. 
         [0088]      FIG. 4C  is a diagram illustrating an image obtained by performing rendering of the HTML file illustrated in  FIG. 4B . Here, by using the UI metadata illustrated in  FIG. 5 , the positions and classifications of pieces of UI information in this image can be known. For example, it is seen that pieces of UI information corresponding to the tags  301  to  306  are arranged at positions  401  to  406  illustrated in  FIG. 4C . The arrangement of these positions is similar to the arrangement of the pieces of UI information  201  to  206  in the browsed state illustrated in  FIG. 4A . This image file may be stored in the storage section (not illustrated) of the integrated server  30  together with the UI metadata. 
         [0089]    The integrated server  30  transmits the UI metadata and image file generated at step S 26  and the session ID issued at step S 22  to the mobile terminal  10  via the communication section  31  (step S 27 ). At this time, the basis contents file is stored into the session DB  35  in association with the transmission-destination mobile terminal  10 , the generated UI metadata, the image file and a session ID. 
         [0090]    The mobile terminal  10  receives the UI metadata, the image file and the session ID via the communication section  11  (step S 12 ). 
         [0091]    When a URL address is transmitted to the integrated server  30  from a different mobile terminal  10  in this state (step S  11 ), the authentication section  34  of the integrated server  30  receives it (step S 21 ), and issues a session ID different from the session ID already issued (step S 22 ). The authentication section  34  assigns an information-for-mobile-terminal generation section  33  (for example, an information-for-mobile-terminal generation section  33 −2) from among the multiple information-for-mobile-terminal generation sections  33  to the session ID (step S 23 ) and stores it into the session DB  35  in association with the session ID. Thereby, a different session ID is assigned to each mobile terminal  10  which communicates with the integrated server  30 . As for the processing at steps S 24  to S 12 , description will be omitted. 
         [0092]    On the other hand, in the case of access from the PC  20 , a session ID is not issued.  FIG. 3B  is a flowchart illustrating an operation performed before a desired webpage is displayed on the display section  24  of the PC  20 . 
         [0093]    When a user inputs the URL address of a webpage which he wants to browse, using the input device  23  of the PC  20 , the URL address and information indicating the PC  20  are transmitted to the integrated server  30  via the communication section  21  (step S 13 ). The information indicating the PC  20  is a user agent here, and it includes information indicating a web browser (a character string including, for example, Mozilla or Opera). 
         [0094]    The integrated server  30  receives this via the communication section  31  (step S 28 ). The authentication section  34  receives the user agent via the communication section  31 . The authentication section  34  analyzes the user agent. When it recognizes that the access is from the PC  20 , and acquires a contents file, such as an HTML file, a CSS file and a Java Script file, corresponding to the received URL address, from the web contents storage area  32  (step S 29 ). 
         [0095]    The integrated server  30  transmits the contents file acquired at step S 29  to the PC  20  via the communication section  31  (step S 30 ). The PC  20  receives the UI metadata, the image file and the session ID via the communication section  11  (step S 14 ). In the case of the PC  20 , it is not necessary to generate UI metadata and an image file because web contents can be immediately browsed by a web browser. Therefore, it is not necessary to issue a session ID. Since the subsequent display process is the same as a well-known process, description thereof will be omitted. 
         [0096]    Next, an internal process of the mobile terminal  10  which has received the UI metadata and the image file will be described with reference to  FIGS. 6A and 6B . 
         [0097]    When the mobile terminal  10  receives the UI metadata, the image file and the session ID via the communication section  11  (step S 41 ), the processing section  12  compares the position coordinates of each of pieces of UI information included in the received UI metadata and the position coordinates of a cursor displayed on the display section  14  (step S 42 ), and displays the image file and the pieces of UI information on the display section  14  on the basis of the result of the comparison (step S 43 ). 
         [0098]    For example, when the position coordinates of the cursor overlaps with the position coordinates of a piece of UI information, a mark is attached to the position of the piece of UI information to make the user recognize that the piece of UI information is selectable. The position may be underlined or surrounded by a square. Here, when the cursor is positioned in a rectangular range with the XY coordinate values of a piece of UI information recorded in the UI metadata as diagonal corners, the position coordinates of the piece of UI information and the position coordinates of the cursor are considered to overlap with each other. Such a mark may be always illustrated at the position of a displayed piece of UI information on an image, instead of being illustrated in the case where the position coordinates overlap. On the contrary, when the position coordinates of the cursor overlaps with the position coordinates of a piece of UI information, the cursor may be displayed with its color or shape changed. 
         [0099]    Here, when a user operation is performed via the input device  13  (step S 44 ), display of the display section  14  is changed according to the contents of the operation. 
         [0100]    For example, when an up-to-down, down-to-up, right-to-left or left-to-right movement operation by the cross key or the like is performed, the cursor or the image is moved according to the operation (step S 45 ). 
         [0101]      FIGS. 7A and 7B  are diagrams illustrating the case where a cursor moves according to an operation.  FIG. 7B  illustrates display in the case where a movement-toward-upper-left operation is performed in the state in  FIG. 7A . When a cursor  502  is moved onto a UI information position  501  (here, a link) at the upper left of the screen according to the user operation, the UI information position  501  is underlined, and the cursor  502  is displayed as a cursor  502 ′ in a changed shape. 
         [0102]    By performing an operation with a decision button, a link destination associated with the UI information position  501  can be displayed as described later. 
         [0103]      FIGS. 8A and 8B  are diagrams illustrating the case of a configuration in which, when an up-to-down, down-to-up, right-to-left or left-to-right movement operation is performed similarly, the image moves according to the operation.  FIG. 8B  illustrates display in the case where a movement-toward-right operation is performed in the state of  FIG. 8A . A cursor  503  is displayed being fixed in the center of the screen on the display section  14 . The displayed image moves according to a user operation. When the UI information position  501  on the image is moved onto the cursor  503 , the UI information position  501  on the image is underlined, and the cursor  503  is displayed as a cursor  503 ′ in a changed color. 
         [0104]    If an enlargement/reduction operation is performed at step S 44 , the image is displayed with a magnification changed according to the operation (step S 46 ). 
         [0105]      FIG. 9  is a diagram for illustrating the image displayed on the display section  14  in the case where an enlargement/reduction operation is performed. When a reduction operation is performed in the state illustrated in Portion A of  FIG. 9 , the image is displayed in a reduced size as illustrated in Portion B of  FIG. 9 . By further operating a reduction operation, the image can be displayed as illustrated in Portion C of  FIG. 9 . 
         [0106]    When an enlargement operation is performed in the state illustrated in Portion C of  FIG. 9 , the image in Portion C of  FIG. 9  is displayed in an enlarged size as illustrated in Portion B of  FIG. 9 . By further operating an enlargement operation, the image can be displayed as illustrated in Portion A of  FIG. 9 . 
         [0107]    In  FIG. 9 , the position of a cursor  504  in the screen is not changed. However, since the display magnification of the displayed image is changed with a position other than the display position of the cursor  504  as the center, the position of the cursor  504  on the image moves. 
         [0108]    As a result, though the position of the cursor  504  does not overlap with a UI information position on the image in the state illustrated in Portion A of  FIG. 9 , a UI information (link) position  505  on the image overlaps with the position of the cursor  504  in the state illustrated in Portion B of  FIG. 9 . Therefore, the UI information position  505  on the image is underlined, and the cursor  504  is displayed as a cursor  504 ′ in a changed shape. 
         [0109]    If an operation by the decision button (a click operation) is performed at step S 44 , it is determined whether or not the cursor position and a UI information position on the image overlap with each other on the basis of the result of the comparison at step S 42  (step S 47 ). 
         [0110]    If the cursor position does not overlap with a UI information position on the image, the processing section  12  nullifies the click operation, the process returns to step S 42  and the processing section  12  performs similar processing. 
         [0111]    If the cursor position overlaps with a UI information position on the image, the processing section  12  determines the classification of UI information which exists at the position overlapping with the cursor position on the basis of the UI metadata (step S 48 ). 
         [0112]    As classifications of UI information, the following three are conceivable: (1) UI information which requires input by the user, such as a text input field, (2) UI information which is not accompanied by screen transition and does not require data input, such as a checkbox and a radio button, and (3) UI information accompanied by screen transition, such as a link and a button. 
         [0113]    In the case where the classification of the UI information existing at the cursor position is (1) UI information which requires input by the user, such as a text input field, a data input screen is displayed on the display section  14  by pop-up or the like to request input from the user (step S 49 ). The user performs necessary data input by the input device  13  on this input screen (step S 50 ). The processing section  12  rewrites UI metadata stored in the storage section (not illustrated) according to the user input (step S 51 ). The rewritten UI metadata is transmitted to the integrated server  30  together with a rewritten UI information ID and the session ID received at step S 41  via the communication section  11  (step S 52 ). 
         [0114]    The details of rewriting of UI metadata will be described with reference to  FIGS. 10A to 10D  and  11 A to  11 C. 
         [0115]      FIG. 10A  is a diagram illustrating that the image illustrated in  FIG. 4C  is displayed on the display section  14 . On positions  401  to  406  on the displayed image, pieces of UI information  201  to  206  are displayed as illustrated in the UI metadata illustrated in  FIG. 11A . When the user moves a cursor  400  onto the position  401  corresponding to the UI information  201  and performs a click operation, a text input pop-up screen is displayed on the display section  14  as illustrated in  FIG. 10B . 
         [0116]    The user inputs desired characters using the input device  13  on this pop-up screen. When a click operation is performed via the input device  13  after inputting text, the processing section  12  rewrites a value attribute of the UI information  201  corresponding to the position  401 , on the basis of the inputted text. Since the user inputs “shibukawa” on the text input pop-up screen as illustrated in  FIG. 10B , the value attribute of the UI information  201  is rewritten to “shibukawa” as illustrated in  FIG. 11B . 
         [0117]    This rewritten UI metadata is transmitted to the integrated server  30  via the communication section  11  together with the ID of the rewritten (executed) UI information (here,  201 ). 
         [0118]    Next, description will be made on the case where corresponding UI information is (2) UI information which is not accompanied by UI screen transition and does not require data input. 
         [0119]    At each of the position  402  corresponding to the UI information  202  and the position  403  corresponding to the UI information  203  illustrated in  FIG. 10C , a radio button for specifying sex is displayed. As illustrated in  FIG. 4 , the basis tags  302  and  303  of the UI information  202  and the UI information  203  have the same name attribute. That is, any one of the UI information  202  and the UI information  203  can be selected. In the default setting, the checked attribute of the UI information  202  is true, and the checked attribute of the UI information  203  is false, as illustrated in  FIG. 11A . Therefore, the UI information  202  is selected as illustrated in  FIG. 10A . 
         [0120]    When the cursor  400  is moved onto the position  403  corresponding to the UI information  203 , and a click operation is performed, the processing section  12  determines the classification of the UI information which exists at the position overlapping the cursor position on the basis of the UI metadata. 
         [0121]    Here, the UI information  203  is a radio button, which is UI information that does not require data input and is not accompanied by screen transition. Therefore, the processing section  12  proceeds to step S 51 , and the processing section  12  rewrites data about the UI information  203  in the UI metadata stored in the storage section (not illustrated). 
         [0122]      FIG. 11C  is a diagram illustrating the UI metadata rewritten in this case. As illustrated in  FIG. 11C , the checked attribute of the UI information  203  has been rewritten to true, and the checked attribute of the UI information  202  which has the same name attribute as the UI information  203  has been rewritten to false. 
         [0123]    Lastly, description will be made on the case where corresponding UI information is (3) UI information accompanied by screen transition. The UI information accompanied by screen transition refers to such UI information that an image different from a currently displayed image is displayed as a result of executing the UI information. 
         [0124]    As illustrated in  FIG. 10D , what is displayed at the position  406  corresponding to the UI information  206  is a transmission button. By performing a click operation at the position  406 , the screen transitions to a different screen in accordance with the description in the button tag  306 . When the cursor  400  is moved onto this position  406 , and a click operation is performed, the processing section  12  determines the classification of UI information which exists at the position overlapping the cursor position on the basis of the UI metadata. 
         [0125]    Here, the UI information  206  is a button, which is UI information accompanied by screen transition. Therefore, the processing section  12  proceeds to step S 52 . Then, the ID of the executed UI information (here,  206 ) and the session ID received at step S 41  are transmitted to the integrated server  30  via the communication section  11  together with the UI metadata (step S 52 ). 
         [0126]    As described above, no matter which classification of UI information a click operation is performed for, UI metadata and the ID of the executed UI information are transmitted to the integrated server  30  together with a session ID. Therefore, the integrated server  30  can certainly acquire information about which webpage was browsed on which mobile terminal  10 , and which operation was operated thereon. 
         [0127]    Next, the operation of the webpage browsing system  100  based on the ID of executed UI will be described with reference to  FIG. 12 . 
         [0128]    When UI metadata, the ID of executed UI information and a session ID are transmitted from the mobile terminal  10  (step S 61 ), the integrated server  30  receives them via the communication section  31  (step S 71 ). 
         [0129]    The authentication section  34  receives the session ID via the communication section  31 , and refers to the session DB  35  to identify an information-for-mobile-terminal generation section  33  associated with the session ID (step S 72 ). 
         [0130]    If, at step S 72 , the session ID is not stored when the session DB  35  is referred to, it is possible to separately issue a session ID and assign an information-for-mobile-terminal generation section  33  in methods similar to those at steps S 22  and S 23 . In this case, the subsequent process can be performed by the information-for-mobile-terminal generation section  33  assigned here. 
         [0131]    When the information-for-mobile-terminal generation section  33 −1 is identified at steps S 72 , the UI information analysis section  33 B−1 acquires the UI metadata and the ID of the executed UI information via the communication section  31 , analyzes them, and analyzes which UI information in the UI metadata was executed (step S 73 ). 
         [0132]    The UI information analysis section  33 B−1 determines whether or not it is necessary to acquire a new contents file, on the basis of the executed UI information (step S 74 ). For example, the determination is made in the case where a link button is operated and screen transition occurs. 
         [0133]    If the executed UI information requires acquisition of a new contents file, a transition-destination URL address is acquired from a contents file stored in the session DB in association with the session ID, and the contents file corresponding to this URL address is acquired from the web contents storage area  32  (step S 75 ). The UI information analysis section  33 B−1 analyzes the contents file of the transition destination (step S 76 ). 
         [0134]    Furthermore, the UI information analysis section  33 B−1 generates UI metadata of the transition destination on the basis of the result of this analysis, and the image conversion section  33 A−1 generates an image file on the basis of the contents file of the transition destination (step S 77 ). The contents file of the transition destination is stored into the session DB  35  in association with the UI metadata and image file of the transition destination and in association with a session ID. The session ID associated here is the same session ID issued at step S 22 . Thereby, processing for a certain session ID is managed together with information about a communication-counterpart mobile terminal  10 . 
         [0135]    The image file and UI metadata of the transition destination, and a session ID are transmitted to the mobile terminal  10  via the communication section  31  (step S 78 ). The session ID transmitted here is the same session ID issued at step S 22 . 
         [0136]    The mobile terminal  10  receives the image file, the UI metadata and the session ID via the communication section  11 , and displays the image file on the display section  14  as a transition-destination screen (step S 62 ). 
         [0137]    If it is determined at step S 73  that the executed UI information is UI information which does not require acquisition of a new contents file, the flow proceeds to step S 77 , where a contents file associated with the session ID received at step S 71 , that is, a contents file corresponding to the rewritten UI metadata is read from the session DB  35 , and a new image file is generated on the basis of the rewritten UI metadata. It is also possible to, on the basis of the image of the original contents file and the ID of the executed UI information, change only a part of the image for which rewriting is required because of the execution, instead of generating a new image file. 
         [0138]    The new image file, the UI metadata and the session ID are transmitted to the mobile terminal  10  via the communication section  31  (step S 78 ). The mobile terminal  10  receives the image file and the UI metadata via the communication section  11  and displays the image file on the display section  14  (step S 62 ). 
         [0139]    For example, if the executed UI information is the UI information  201  (a text input field) illustrated in  FIG. 10A , the rewritten UI metadata illustrated in  FIG. 11B  and the ID  201  of the executed UI information are transmitted from the mobile terminal  10  (step S 61 ). The integrated server  30  receives them via the communication section  31  (step S 71 ). 
         [0140]    The image conversion section  33 A reads a contents file associated with the rewritten UI metadata from the storage section (not illustrated), and generates a new image file on the basis of the rewritten UI metadata. This new image file is an image in which the character “shibukawa” inputted at step S 50  is displayed at the position of a text input field, as illustrated in  FIG. 10C . 
         [0141]    If the executed UI information is the UI information  203  (a radio button) illustrated in  FIG. 10C , the rewritten UI metadata illustrated in  FIG. 11C  and the ID  203  of the executed UI information are transmitted from the mobile terminal  10  (step S 61 ). The integrated server  30  receives them via the communication section  31  (step S 71 ). 
         [0142]    The image conversion section  33 A reads a contents file associated with the rewritten UI metadata from the storage section (not illustrated), and generates a new image file on the basis of the rewritten UI metadata. This new image file is an image in which the position of the radio button checkmark is changed from the position  402  to the position  403 , as illustrated in  FIG. 10D . 
         [0143]    Furthermore, if the executed UI information is the UI information  206  (a button) illustrated in  FIG. 10D , the UI metadata (which is not rewritten, in this case) and the ID  206  of the executed UI information are transmitted from the mobile terminal  10  (step S 61 ). The integrated server  30  receives them via the communication section  31  (step S 71 ). 
         [0144]    The integrated server  30  which has received them acquires a transition-destination URL from the UI metadata, requires (step S 74 ) and receives (step S 75 ) a relevant contents file from a relevant external web server  50 . On the basis of this contents file, UI metadata is generated by the UI information analysis section  33 B−1, and an image file is generated by the image conversion section  33 A (step S 76  and S 77 ). 
         [0145]    This image file and UI metadata of the transition destination are transmitted to the mobile terminal  10  (step S 78 ), and the image file is displayed on the display section  14  (step S 62 ). 
         [0146]    As described above, even when a UI operation accompanied by screen transition is performed, a new transition-destination webpage can be displayed and, furthermore, UI information can be operated similarly. 
         [0147]    Since the mobile terminal  10  receives a session ID at step S 62 , it is possible to, when UI information is executed on the mobile terminal  10  next, transmit the UI metadata and the ID of the executed UI information to the integrated server  30  together with the session ID. In the integrated server  30 , since a different session ID is assigned to each of mobile terminals  10  which communicate with the integrated server  30  and stored in the session DB, it is possible to manage connection with the mobile terminals  10  and processing performed thereon, for each session ID, that is, for each mobile terminal  10 . 
         [0148]    As described above, the webpage browsing system  100  can realize high-speed and user-friendly webpage browsing. Especially, because contents files are stored in the integrated server  30 , the speed can be further increased in comparison with the case of acquiring a contents file from an external web server. Furthermore, it is possible for multiple mobile terminals  10  to connect to the integrated server  30 , and it is possible to manage processing for each of the mobile terminals  10 . 
         [0149]    In this embodiment, a session ID, the information-for-mobile-terminal generation section  33 −1 and a user agent are stored into the session DB in association with one another (step S 23 ). However, it is not necessarily required to store the user agent in association with the session ID. However, by associating the user agent with the session ID, generate an image, it is possible for the image conversion section  33 A to generate an image with a size suitable for the display section of the mobile terminal  10  or an image with a data amount suitable for the processing ability of the mobile terminal  10 . Therefore, it is desirable to associate the user agent also with the session ID and the like. In order for the image conversion section  33 A to generate an image with a size suitable for the display section of the mobile terminal  10  or an image with a data amount suitable for the processing ability of the mobile terminal  10  in the case where a user agent is not stored in association with a session ID, a user agent can be transmitted each time a URL address and the ID of executed UI information are transmitted from the mobile terminal  10 . 
         [0150]    In this embodiment, the integrated server  30  which includes the function of an external web server is used. However, an external web server and a relay server may be separately provided as illustrated in a second embodiment. Furthermore, such a configuration is also possible that the integrated server can connect to multiple external web servers existing in the Internet. The integrated server  30  and the external web servers are connected via the Internet, and each of the communication section  31  and the communication sections of the external web servers performs communication in accordance with standard Internet protocols. Thereby, even a contents file which is not stored in the integrated server  30  can be browsed (as for a method for the integrated server  30  to acquire a contents file from an external web server, see the second embodiment). 
       Second Embodiment 
       [0151]    The second embodiment is such that an authentication function of authenticating a communication-counterpart mobile terminal  10  is provided. A webpage browsing system  101  according to the second embodiment will be described below. The same portions as in the first embodiment are given the same reference numerals, and description thereof will be omitted. Since the internal process of a mobile terminal  10  is the same as that in the first embodiment, description thereof will be omitted. 
         [0152]      FIG. 13  is a diagram illustrating an example of the whole configuration of the webpage browsing system  101 . As illustrated in  FIG. 13 , the webpage browsing system  101  includes multiple mobile terminals  10  used by users and a relay server  40  which relays communication between the mobile terminals  10  and an external web server  50 . 
         [0153]    The relay server  40  includes a communication section  41 , multiple information-for-mobile-terminal generation sections  42  (each of which includes an image conversion section  42 A and a UI information analysis section  42 B), an authentication section  43 , a session DB  44  and a user DB  45 . 
         [0154]    The communication section  41  controls communication with the mobile terminals  10  and controls communication with the external web server  50 . The relay server  40  and the external web server  50  are connected via the Internet, and each of the communication section  41  and a communication section  51  performs communication in accordance with standard Internet protocols. 
         [0155]    There exist the same number of information-for-mobile-terminal generation section  42  as the number of session IDs issued by the authentication section  43  to be described later. The information-for-mobile-terminal generation section  42  includes the image conversion section  42 A and the UI information analysis section  42 B. Since the image conversion section  42 A is the same as the image conversion section  33 A, and the UI information analysis section  42 B is the same as the UI information analysis section  33 B, description thereof will be omitted. The concept of having multiple information-for-mobile-terminal generation sections  42  includes the case where there are multiple information-for-mobile-terminal generation sections  42 , the case where there is one information-for-mobile-terminal generation section  42  in which each of the image conversion section  42 A and the UI information analysis section  42 B are divided into multiple areas, and the like, similarly to the first embodiment. 
         [0156]    In the user DB  45 , information about a mobile terminal  10  for which the relay server  40  relays communication with the external web server  50  is stored together with a user ID. The information about a mobile terminal  10  is information indicating the mobile terminal  10 , such as a user agent, a password and the like. 
         [0157]    When a mobile terminal  10  connects to the communication section  41 , the authentication section  43  acquires information indicating the mobile terminal  10  (for example, a user agent) from the mobile terminal  10  and determines whether the acquired information indicating the mobile terminal  10  is stored in the user DB  45 . If the acquired information indicating the mobile terminal  10  is stored in the user DB  45 , the authentication section  43  issues a session ID. Thereby, it is possible to perform relay to the external web server  50  only for a determined mobile terminal  10 . 
         [0158]    Then, the authentication section  43  associates one of the multiple information-for-mobile-terminal generation sections  42  with the issued session ID, stores information about the association into the session DB  44  to perform session management. Thereby, separate communication can be made with each of the multiple mobile terminals  10 . 
         [0159]    If the mobile terminal  10  does not access for a predetermined time or more after the session ID is issued, the authentication section  43  ends (terminates) the session and deletes the data about the session ID stored in the session DB. Thereby, it becomes possible to issue the session ID when another mobile terminal  10  or the like accesses. 
         [0160]    The external web server  50  includes a communication section  51  and a storage section  52 . 
         [0161]    The communication section  51  controls communication with the relay server  40 . The storage section  52  stores the contents file of webpages established in the external web server  50 . The communication section  51  reads a file in response to a URL request received from the relay server  40  and transmits it to the relay server  40 . 
         [0162]    Though only one external web server  50  is illustrated in  FIG. 13 , there are a lot of external web servers  50  in the Internet network which can communicate with the relay server  40 , and the relay server  40  can communicate with each of the external web servers  50 . Thus, no matter which mobile terminal  10  accesses which external web server  50 , communication is performed via the relay server  40 . 
         [0163]    Next, the operation of the webpage browsing system  101  configured as described above will be described. First, the operation performed before a desired webpage is displayed on a display section  14  of the mobile terminal  10  will be described with reference to  FIG. 14 . 
         [0164]    When the URL address of a webpage to be browsed is inputted with the use of an input device  13  of the mobile terminal  10 , the mobile terminal  10  transmits the URL address and information indicating the mobile terminal  10  to the relay server  40  via the communication section  11  (step S 11 ). 
         [0165]    The relay server  40  receives the URL address and information indicating the mobile terminal  10  transmitted from the mobile terminal  10 , via the communication section  41  (step S 21 ). The communication section  41  outputs the information indicating the mobile terminal  10  to the authentication section  43 , and the authentication section  43  determines whether the information indicating the mobile terminal  10  is stored in the user DB  45 . If the information indicating the mobile terminal  10  is stored in the user DB  45 , the authentication section  43  issues a session ID (step S 101 ). 
         [0166]    The authentication section  43  assigns an information-for-mobile-terminal generation section  33 −1 to the session ID, and causes the session ID, the information-for-mobile-terminal generation section  33 −1 and a user agent to be stored into the session DB in association with one another (step S 23 ). 
         [0167]    The communication section  41  transmits the received URL address to an external web server  50  corresponding to the URL (step S 102 ). If a webpage title is selected with the use of a bookmark in the integrated server  30 , a corresponding URL address can be read from the storage section (not illustrated) and transmitted to a relevant external web server  50 . 
         [0168]    The corresponding external web server  50  receives this URL address via a communication section  31  (step S 111 ). Then, the external web server  50  reads a contents file, such as an HTML file, a CSS file and a Java Script file, corresponding to the received URL address from the storage section  52  and transmits it to the relay server  40  via the communication section  51  (step S 112 ). 
         [0169]    The communication section  41  receives the contents file transmitted from the external web server  50  (step S 103 ). The received contents file is outputted to an image conversion section  33 A−1 and a UI information analysis section  33 B−1. 
         [0170]    The UI information analysis section  33 B−1 analyzes the contents file and extracts UI information (step S 25 ). The UI information analysis section  33 B−1 generates UI metadata on the basis of the result of this analysis, and the image conversion section  33 A−1 performs rendering of the contents file and generates an image file in a format which can be displayed on the display section  14  of the mobile terminal  10  (step S 26 ). 
         [0171]    The relay server  40  transmits the UI metadata and image file generated at step S 26  and the session ID issued at step S 22  to the mobile terminal  10  via the communication section  41  (step S 27 ). At this time, the basis contents file is stored into the session DB  44  in association with the transmission-destination mobile terminal  10 , the generated UI metadata, the image file and the session ID. The mobile terminal  10  receives the UI metadata and the image file via the communication section  11  (step S 12 ). 
         [0172]    Thereby, it is possible to transmit UI metadata and an image file to a mobile terminal  10  registered with the user DB  45  in advance. 
         [0173]    Next, the operation of the webpage browsing system  101  based on the ID of executed UI information will be described with reference to  FIG. 15 . 
         [0174]    When UI metadata, the ID of executed UI information and a session ID are transmitted from a mobile terminal  10  (step S 61 ), the relay  40  receives them via the communication section  41  (step S 71 ), and the authentication section  43  refers to the session DB  44  to identify an information-for-mobile-terminal generation section  33 −1 associated with the received session ID (step S 72 ). 
         [0175]    The UI information analysis section  33 B−1 analyzes the UI metadata and the ID of the executed UI information which have been received, and analyzes which UI information in the UI metadata was executed (steps S 73 ). 
         [0176]    The UI information analysis section  33 B−1 determines whether or not it is necessary to acquire data from an external web server  50  (step S 121 ) on the basis of the executed UI information. For example, the determination is made in the case where a link button is operated and screen transition occurs. 
         [0177]    If it is necessary to acquire data from an external web server  50  (steps S 121 : YES), the communication section  41  transmits the received URL address to an external web server  50  corresponding to the URL address (step S 122 ). If a webpage title is selected with the use of a bookmark in the integrated server  30 , a corresponding URL address can be read from the storage section (not illustrated) transmitted to a relevant external web server  50 . 
         [0178]    The relevant external web server  50  receives this URL address via the communication section  31  (step S 81 ). Then, the external web server  50  reads a contents file, such as an HTML file, a CSS file and a Java Script file, corresponding to the received URL address from the storage section  52  and transmits it to the relay server  40  via the communication section  51  (step S 82 ). 
         [0179]    The communication section  41  receives the contents file of the transition destination and outputs it to the information-for-mobile-terminal generation section  33 −1. The UI information analysis section  33 B−1 analyzes the contents file of the transition destination (step S 76 ). 
         [0180]    Furthermore, the UI information analysis section  33 B−1 generates UI metadata of the transition destination on the basis of the result of this analysis, and the image conversion section  33 A−1 generates an image file on the basis of the contents file of the transition destination file (step S 77 ). The image file and UI metadata of the transition destination, and a session ID are transmitted to the mobile terminal  10  via the communication section  41  (step S 78 ). 
         [0181]    The mobile terminal  10  receives the image file, the UI metadata and the session ID via the communication section  11 , and displays the image file on the display section  14  as a transition-destination screen (step S 62 ). 
         [0182]    If it is not necessary to acquire data from an external web server  50  (step S 121 : NO), the flow proceeds to step S 77 , where the image conversion section  33 A−1 reads the created (rewritten) UI metadata and a related contents file from the storage section (not illustrated) in the image conversion section  42 A, and generates a new image file on the basis of the created (rewritten) UI metadata. It is also possible to, on the basis of the image of the original contents file and the ID of the executed UI information, change only a part of the image for which rewriting is required because of the execution, instead of generating a new image file. 
         [0183]    The new image file, the UI metadata and the session ID are transmitted to the mobile terminal  10  via the communication section  41  (step S 78 ). The mobile terminal  10  receives the image file, the UI metadata and the session ID via the communication section  11 , and displays the image file on the display section  14  (step S 62 ). 
         [0184]    As described above, the webpage browsing system  101  can realize high-speed and user-friendly webpage browsing. Furthermore, by issuing a session ID only to a mobile terminal registered with the user DB, an authentication function can be provided. Therefore, security can be enhanced. 
         [0185]    Though the webpage browsing system  101  of this embodiment includes the mobile terminals  10 , the relay server  40  and the external web server  50 , an integrated server which includes a relay server and an external web server can be used similarly to the first embodiment. However, because there is provided an authentication function of issuing a session ID only to a mobile terminal  10  registered with the user DB  45  in this embodiment, it is desirable that the function of a web server to which an unspecified number of users may connect should be separated from the relay server. 
       Third Embodiment 
       [0186]    A third embodiment is different from the first or second embodiment only in the internal process of a mobile terminal  10 . 
         [0187]      FIGS. 16A and 16B  are flowcharts illustrating the internal process of the mobile terminal  10  of the third embodiment. Portions common to the flowcharts in  FIGS. 6A and 6B  are given the same reference numerals, and description thereof will be omitted. 
         [0188]    In the case where text is inputted at position  401  corresponding to UI information  201  in the state illustrated in  FIG. 10A , UI metadata is rewritten as illustrated in  FIG. 11B . At this time, the mobile terminal  10  of the third embodiment does not perform communication with an integrated server  30  but a processing section  12  generates the image illustrated in  FIG. 10C  (step S 91 ). After that, the flow returns to step S 42 , and similar processing is performed. 
         [0189]    Similarly, in the case where position  403  corresponding to UI information  203  is clicked in the state illustrated in  FIG. 10C  also, communication with the integrated server  30  is not performed, and the processing section  12  generates the image illustrated in  FIG. 10D  in which a check position has moved. After that, the flow returns to step S 42 , and similar processing is performed. 
         [0190]    As described above, by making such a configuration that, when image rewriting occurs without being accompanied by screen transition, the mobile terminal  10  rewrites the image, it is possible to reduce the amount of communication between the mobile terminal  10  and the integrated server  30  and, furthermore, eliminate the communication time therefor, and therefore, it is possible to improve the operability of the mobile terminal  10 . 
       Fourth Embodiment 
       [0191]    A fourth embodiment is different from the first or second embodiment only in the internal process of a mobile terminal  10 . 
         [0192]      FIGS. 17A and 17B  are flowcharts illustrating the internal process of the mobile terminal  10  of the fourth embodiment. Portions common to the flowchart in  FIGS. 6A and 6B  are given the same reference numerals, and description thereof will be omitted. 
         [0193]    The mobile terminal  10  of the fourth embodiment is different from that of the first embodiment in that visual-effect giving processing is performed according to a cursor position and a UI information position. 
         [0194]    When an up-to-down, down-to-up, right-to-left or left-to-right movement operation by a cross key or the like is performed at step S 45  in  FIGS. 17A and 17B , a processing section  12  moves the cursor or the image according to the operation. 
         [0195]    When the movement operation ends, the position coordinates of the cursor after the movement is calculated, and it is determined whether or not the calculated position coordinates are near the area where UI information exists, on the basis of the calculated position coordinates and UI metadata (step S 92 ). Here, it is determined whether they are near or not, on the basis of a predetermined number of pixels as a threshold. This threshold can be determined according to the enlargement rate or the like of the image displayed on a display section  14 . 
         [0196]    If it is determined that the position coordinates are not near, the flow proceeds to step S 42  similarly to the first embodiment. If it is determined that they are near, the processing section  12  performs visual-effect giving processing (step S 93 ). 
         [0197]    For example, the cursor is automatically moved to a position corresponding to the nearest UI information as illustrated in  FIG. 18 . In the example of  FIG. 18 , a cursor  506  is automatically moved to UI information position  501 , changed to a cursor  506 ′ and displayed on the UI information position  501 . While the cursor  506  is moving, residual images  506   a,    506   b,    506   c  and  506   d  are displayed on the locus of the movement. 
         [0198]    In the case of a configuration in which an image moves according to an operation, the image can be moved so that UI information nearest to a cursor fixed in the center of the screen overlaps the cursor. 
         [0199]    By making a configuration as described above, it is possible to improve the operability at the time of browsing a website.