Abstract:
A web page acquisition system, provider, method, computer readable memory and program of instructions for web page acquisition that reduces the waiting time that is experienced by a user who accesses a network site when the network is busy and also reduces the load that is imposed on the server of a provider.

Description:
CLAIM FOR PRIORITY 
   This application claims priority from Japanese Application No. 2000-091874, filed on Mar. 29, 2000, and which is hereby incorporated by reference as if fully set forth herein. 
   FIELD OF THE INVENTION 
   The present invention relates to a web page acquisition service for supporting operations of obtaining web pages from web servers through connections to the Internet, and browsing the thus obtained web pages. 
   BACKGROUND OF THE INVENTION 
   The number of users who at any time access the currently popular Internet tends to correspond to a time axis reflecting the life patterns of the users. That is, since many people who use the Internet work in the daytime, for their personal convenience, they tend to log on in large numbers at night, and as a result, communication traffic is greatly increased and the network facilities become congested. 
   When the volume of the traffic carried by a communication network is increased, accordingly, the time required for data transfer is extended. Thus, at night, when the Internet is crowded, after sending a connection request to a desired Internet site, a user must wait for an extended period of time before he or she is able to complete the downloading of the web page source for the site. An indication that, which indicate that the work efficiency has been deteriorated. 
   Furthermore, since the general run of users employs dial-up, telephone line connections to access the Internet, if the time required for such a user to complete a data transfer is extended, the charges the user incurs for the line connection time will increase rapidly, which is definitely not economically preferable. 
   Internet service providers are also affected when the large majority of accesses take place during a specific time period. The load imposed in such a case is excessive, and may deteriorate the ability of a provider to service clients properly. 
   The autopilot program that is now available makes it possible for a user to avoid having to access the congested Internet. A user installs the autopilot program on his or her client machine, and sets it so that at a designated time it automatically accesses a provider and obtains an Internet connection. Thereafter, the program automatically transmits a connection request to a previously registered site, and downloads a desired web page source. When the autopilot program is set for activation in a time period during which traffic is not heavy, the time spent waiting to obtain a web page source can be reduced. 
   Also, providers normally have availability on their servers cache functions for the temporary storage of web page sources for sites that users have accessed. Therefore, for the web page of a site that a user frequently accesses, so long as the data for the site is available in the cache memory of the server, the web page source held by the server can be transmitted directly to the client machine of the user when the user issues another connection request. In this manner, since the intercommunication between the provider and the web site is not performed, the time the user is forced to wait can be shortened even more. 
   As is described above, since the communication traffic volume is increased when many users access the Internet simultaneously, the time a user spends waiting is extended and work efficiency is thereby deteriorated, and since when waiting time is extended the line connection charges accrued by the user are increased, this is an economically unacceptable condition. 
   Further, for a provider, the load imposed on a server is increased when there is a high concentration of accesses. And when a user employs the autopilot program in order to avoid accessing the Internet when traffic is heavy, although for the user this means effectively suppresses the waiting time extension and the line connection charge increase, for a provider little or no actual relief is afforded, since the load imposed on the server of the provider will not be reduced unless a considerable number of users begin to access the Internet at widely distributed times. 
   Furthermore, although, as is described above, the server of a provider may have a cache function, when the cache memory has been filled, data stored in the cache memory are mechanically deleted, beginning with the oldest data. Therefore, when a user accesses the cache memory, the data the user desires will not always be available therein which makes user&#39;s waiting time longer than expected. 
   There thus continues to be a need to further shorten the time a user must wait when accessing a web page on a network during a busy time period, and to reduce the load imposed on the server of a provider. 
   SUMMARY OF THE INVENTION 
   The present invention broadly contemplates a system and method for web page acquisition which reduces the waiting time experienced by a user who accesses a network site when the network is busy and reduces the load imposed on the server of a provider. 
   In accordance with one aspect of the present invention, a web page acquisition service system comprises a web page acquisition server and a user terminal, both of which are connected to a communication network, wherein the user terminal transmits to the web page acquisition server a web page acquisition request that includes various acquisition conditions; and wherein, in accordance with the acquisition conditions included in the web page acquisition request received from the user terminal, the web page acquisition server acquires a web page source from a web server on the communication network and transmits the web page source to the user terminal. 
   As one of the acquisition conditions included in the web page acquisition request, the user terminal designates a time condition for the acquisition of a web page source. In accordance with the time condition designated in the web page acquisition request, the web page acquisition server acquires the web page source and transmits the web page source to the user terminal. As the time condition, a time can be set whereat the user terminal issues a web page transmission request to the web page acquisition server. This arrangement is preferable because it ensures that a user can obtain a desired web page at a desired time. 
   The web page acquisition server preferably performs scheduling for the acquisition of a web page source, while taking into account the time condition that is designated in the web page acquisition request and the volume of the communication traffic carried by the communication network. This arrangement is preferable because, since the web page can be acquired at a time whereat communication traffic is not heavy, the load imposed on the web page acquisition server can be reduced. 
   As one of the acquisition conditions included in the web page acquisition request, the user terminal designates a time limited period for the acquisition of a web page source. During the designated time limited period contained in the web page acquisition request, the web page acquisition server acquires and transmits, to the user terminal, the web page source. This arrangement is superior because the web page source can be acquired within a desired time period for which both the starting and the ending times can be designated. 
   When the web page acquisition server receives from a plurality of user terminals a plurality of web page acquisition requests for the same page, the web page acquisition server obtains and archives a corresponding web page source for the plurality of requests, and transmits the web page source to the user terminals that issued the web page acquisition requests. This arrangement is preferable because, since the overlapping web page acquisition requests can be collectively processed, the load imposed on the web page acquisition server can be reduced. 
   According to another aspect of the present invention, a provider, for providing a service for the acquisition of an Internet connection, comprises: a request acceptance unit for accepting from a user a web page acquisition request that includes a web page acquisition condition; a web page acquisition/archiving unit for obtaining a web page source from a web server and for archiving the web page source in accordance with the web page acquisition condition included in the web page acquisition request; and a transmission control unit for, in accordance with the web page acquisition condition, transmitting the web page source to the user who issued the web page acquisition request. 
   The transmission control unit forms into a library file the web page source that, in accordance with the web page acquisition request, is obtained and held in the web page acquisition/archiving unit, and transmits the library file to the user terminal. This arrangement is preferable because a user can handle those required web page sources as a single local file. 
   When a limitation is placed on the size of a data file that the user terminal, which is a web page source transmission destination, can receive as a single transmission, the transmission control unit divides, into segments having an appropriate size for the user terminal, the web page source that is held in the web page acquisition/archiving unit, and forms the segments into library files. This arrangement is preferable because even when the data file a user terminal can receive as a single transmission is small, the web page acquisition service can be provided for the user. 
   The transmission control unit changes a link for the web page source held by the web page acquisition/archiving unit from an absolute link, based on the URL of a web page source, into a relative link. With this arrangement, the user terminal is enabled to handle a web page as a local file. 
   According to another aspect of the present invention, a web page acquisition method, which is employed by a web page acquisition server provided on a communication network, is provided and comprises the steps of: accepting, from a user, a web page acquisition request that includes a web page acquisition condition; employing the web page acquisition condition to prepare a schedule for the acquisition of a web page source; acquiring, across the communication network in accordance with the schedule, the web page source from the web server, and archiving the web page source; and transmitting the web page source to the user in accordance with the web page acquisition condition included in the web page acquisition request. 
   The step of preparing the schedule includes a step of: determining in accordance with a time condition that is included in the web page acquisition request, and while taking into account the volume of the communication traffic across the communication network, the time at which to acquire the web page source designated in the web page acquisition request, and to thereby reduce the load imposed on the web page acquisition server. This arrangement is preferable because, since a web page can be obtained while avoiding time periods during which heavy communication traffic may be encountered, acquisition of the web page can be performed efficiently. 
   The step of preparing the schedule includes a step of: comparing time conditions included in a plurality of web page acquisition requests, submitted by multiple users, when, at the step of receiving the plurality of the web page acquisition requests, it is determined that all of the web page acquisition requests were submitted for the acquisition of the same web page source, and of preparing a schedule so that the minimum number of repetitions is required for the acquisition, from a web server, of the web page source. This arrangement is preferable because, since the overlapping web page acquisition requests can be collectively processed, acquisition of a web page can be performed efficiently. 
   According to another aspect of the present invention, a web page acquisition method, employed by an information terminal device connected to the Internet, is provided and which comprises the steps of: transmitting, to a provider, a web page acquisition request in which web page acquisition conditions are designated; issuing a web page transmission request to the provider based on a time condition that is included in the web page acquisition conditions; and receiving a web page source that, in accordance with the web page transmission request, is transmitted by the provider and that was acquired under conditions corresponding to those included in the web page acquisition conditions. 
   The step for issuing the web page transmission request includes a step of: issuing, upon the receipt of a notification indicating that a web page has been acquired by the provider, the web page transmission request to the provider, regardless of the time condition that is included in the web page acquisition conditions. This arrangement is preferable because after a desired web page is obtained from a provider, an arbitrary timing can be used for the browsing of the web page. 
   At the step of receiving the web page source, the web page source can be received in the form of a library file. 
   According to another aspect of the present invention, a storage medium is provided on which computer input means can store a computer-readable program that permits the computer to perform: a process for accepting, from a user, a web page acquisition request that includes a web page acquisition condition; a process for employing the web page acquisition request to prepare a schedule for the acquisition of a web page source; a process for acquiring, across the communication network in accordance with the schedule, the web page source from the web server, and archiving the web page source; and a process for transmitting the web page source to the user in accordance with the web page acquisition condition included in the web page acquisition request. This arrangement is preferable because all the computers that have installed this program can provide a web page acquisition service. 
   According to another aspect of the present invention, a program transmission apparatus is provided, which comprises: storage means for storing a computer-readable program that permits a computer to perform a process for accepting, from a user, a web page acquisition request that includes a web page acquisition condition, a process for employing the web page acquisition request to prepare a schedule for the acquisition of a web page source, a process for acquiring, across the communication network in accordance with the schedule, the web page source from the web server, and archiving the web page source, and a process for transmitting the web page source to the user in accordance with the web page acquisition condition included in the web page acquisition request; and transmission means for reading the program from the storage means and for transmitting the program. This arrangement is preferable because all the computers that have downloaded this program can provide a web page acquisition service. 
   According to another aspect of the present invention, a program storage device readable by machine, tangibly embodying a program of instructions executable by the machine to perform a method for web page acquisition is provided, said method comprising the steps of: accepting, from a user, a web page acquisition request that includes a web page acquisition condition; employing said web page acquisition condition to prepare a schedule for the acquisition of a web page source; acquiring, across said communication network in accordance with said schedule, said web page source from said web server, and archiving said web page source; and transmitting said web page source to said user in accordance with said web page acquisition condition included in said web page acquisition request. 
   According to yet another aspect of the present invention, a program storage device readable by machine, tangibly embodying a program of instructions executable by the machine to perform a method for web page acquisition is provided, said method comprising the steps of: transmitting, to a provider, a web page acquisition request in which web page acquisition conditions are designated; issuing a web page transmission request to said provider based on a time condition that is included in said web page acquisition conditions; and receiving a web page source that, in accordance with said web page transmission request, is transmitted by said provider and that was acquired under conditions corresponding to those included in said web page acquisition conditions. 
   For a better understanding of the present invention, together with other and further features and advantages thereof, reference is made to the following description, taken in conjunction with the accompanying drawings, and the scope of the invention that will be pointed out in the appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a diagram for explaining the concept of a web page acquisition service according to one embodiment of the present invention. 
       FIG. 2  is a diagram showing the general configuration of a system that carries out the web page acquisition service in accordance with the embodiment. 
       FIG. 3  is a diagram for explaining the arrangement of a web page acquisition server that is established for a provider. 
       FIG. 4  is a diagram showing an example format for a user profile that a user transmits via a user terminal. 
       FIG. 5  is a diagram showing an example format for a web page acquisition request that a user transmits via a user terminal. 
       FIG. 6  is a flowchart for explaining the overview of the operation performed by the web page acquisition server of this embodiment. 
       FIG. 7  is a diagram for explaining an example for the integration of two web page acquisition requests and the preparation of an acquisition list wherein no overlapping information is present. 
       FIG. 8  is a diagram for explaining an example table that is prepared using the acquisition list in  FIG. 7 . 
       FIG. 9  is a diagram for explaining an example schedule that is prepared using the acquisition list in  FIG. 7 . 
       FIG. 10  is a flowchart for explaining the process performed when recurrently preparing a schedule  901  while obtaining a web page. 
       FIG. 11  is a diagram for explaining a virtual tree structure for a web page archival database. 
       FIG. 12  is a diagram showing an example table that is prepared for the tree structure in  FIG. 11 . 
       FIG. 13  is a diagram showing the state of the table in  FIG. 8  when all the web page sources requested by a user 01 have been downloaded. 
       FIG. 14  is a diagram showing the linking processing performed when the downloading up to the second level of the web page for www.aaa.co.jp has been requested. 
       FIG. 15  is a diagram showing the tree structure of the web page sources that are transmitted to the user. 
       FIG. 16  is a flowchart for explaining the operation performed by a transmission control unit when data division and transmission are designated. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   The present invention will now be described during the course of an explanation of the preferred embodiment given while referring to the accompanying drawings. 
     FIG. 1  is a diagram for explaining the concept of a web page acquisition service according to the present invention. And  FIG. 2  is a diagram showing the general arrangement of a system that, in accordance with the embodiment, provides a web page acquisition service. 
   In  FIG. 1 , the web page acquisition service of this embodiment is furnished by a provider  110  that is located between a user  120  and a web site  130 . While as shown in  FIG. 2 , the system employed for this embodiment comprises a web page acquisition server  210 , a user terminal  220  and a web server  230 , all of which are connected to the Internet  200 . 
   In  FIG. 1 , the web page acquisition server  210  shown in  FIG. 2  is used as the provider  110 . And the user  120  operates the user terminal  220  in order to receive a service provided by the web page acquisition server  210 . The web site  130  is included in the web server  230  to provide various web page sources. 
   An overview of the services provided by this embodiment will now be explained while referring to  FIG. 1 . The user  120  accesses the provider  110 , and transmits to the provider  110  a request, accompanied by a user profile, for the acquisition of a web page from a desired web site  130 . It should be noted that the profile of the user  120  must be transmitted to the provider  110  only once, and is not required each time an access is made. Subsequently, based on the request received from the user  120 , the provider  110  obtains a web page from the web site  130  and archives it, following which it issues a notification to the user  120  that the web page has been acquired and transmits the web page to the user  120 . 
     FIG. 3  is a diagram for explaining the configuration of the web page acquisition server  210  that has been incorporated in the provider  110 . In  FIG. 3 , a request acceptance unit  310  accepts and manages a web page acquisition request and a profile issued by the user terminal  220 . A web page acquisition/archiving unit  320  obtains a web page from the web server  230  and archives it in accordance with the web page acquisition request submitted by the user terminal  220 , which is accepted by the request acceptance unit  310 . A transmission control unit  330  controls the transmission to the user terminal  220  of the web page acquired by the web page acquisition/archiving unit  320 . 
     FIG. 4  is a diagram showing an example format for a user profile that the user  120  transmits from the user terminal  220 . As is shown in  FIG. 4 , the user profile includes an Email (Electronic mail) address for issuing a notification to the user  120 , the maximum data size that the user terminal  220  can receive at one time (the maximum transmission size), and information as to whether data division and transmission should be performed when the data size exceeds the maximum transmission size. The user profile may also include the URL (Uniform Resource Locator) of a web page for which the pertinent user  120  desires periodical acquisition, and the frequency and the depth employed for the acquisition of the pertinent web page. 
   If data division and transmission is designated as information included in the user profile, when the size of the data for a desired web page exceeds the maximum transmission size, a request can be issued to the provider  110  to divide the data file into data segments that are equal to or smaller than the maximum transmission size, and to transmit the data segments. When data division and transmission are not designated, however, only that data which corresponds in size to the maximum transmission size will be transmitted. 
   The data list for a bookmark managed by a web browser can be used as the URL for a web page. 
   The frequency of the acquisition performed by a web page is the frequency whereat the web page of a designated URL is obtained. In  FIG. 4 , the web page for which the URL is www.aaa.co.jp is so designated that it will be acquired three times a week, on Monday, Wednesday and Friday, and the web page for which the URL is www.bbb.co.jp/news is so designated that it will be obtained every day. For example, since at the web site  130  whereat news stories are provided the article content is updated every day, daily acquisition of the web page can be designated, while, for the web site  130  whereat data content is not updated so frequently, acquisition of the web page every several days can be designated. 
   The depth employed for the acquisition of a web page is the distance the web page links must be traced to reach a web page source. For example, at the web site  130 , whereat news articles are provided, the headline for each article is entered at the first level on the web page, and the contents of each article are written at the second level. Thus, when one wishes to understand the types of news that are available at the web site  130 , the first level is designated the acquisition depth. Whereas when one wishes to obtain article content, the second level is designated the acquisition depth. 
     FIG. 5  is a diagram showing an example format for a web page acquisition request that is issued by the user  120  while employing the user terminal  220 . The web page acquisition request includes a list of the URLs for the web page that is to be obtained, and the time required for the downloading the web page and the acquisition depth. The time limited period for the acquisition of a pertinent web page can also be designated. When the time for the downloading of a web page is designated as information that is to be included in a web page acquisition request, the provider  110  can be notified of the time limit set by the user  120  for the downloading of the pertinent web page. When the time limited period for the acquisition of a web page is designated in addition to the web page downloading time, the time is provided whereat the information contained on the web page that is to be obtained can be designated. For example, when downloading a web page to acquire news at the web site  130  whereat news articles are provided, the news will be old if the web page is obtained too early. Further, a time limit may be set up that depends on the web page content that is to be acquired. Therefore, since a time limited period for the acquisition of the web page is designated, the web page can be obtained at an appropriate time. 
   The information in  FIGS. 4 and 5 , which is included in the user profile and in the web page acquisition request, is merely an example. Actually, the format can be so designed that not only can requisite information, such as the URL of a web page and an acquisition depth, be obtained, but also various other information can be acquired in accordance with a service that is provided. Furthermore, when information concerning the user profile, which is user information that is registered in advance, and information included in a web page acquisition request, which is transmitted, as needed, with desired content, are combined and used, a variety of services can be received. 
   The request acceptance unit  310  accepts the user profile and the web page acquisition request, and manages the information for the user  120 . In  FIG. 3 , the request acceptance unit  310  includes a profile manager  311 , for managing a user profile received from the user  120 , and a request manager  312 , for managing a web page acquisition request. The profile manager  311  stores and manages the accepted user profile in a user management database  340 , and for the scheduling process, which will be described later, transmits the user profile, as well as the web page acquisition request, to the web page acquisition/archiving unit  320 . Thereafter, for the scheduling process, the request manager  312  transmits the accepted web page acquisition request to the web page acquisition/archiving unit  320 . 
   The web page acquisition/archiving unit  320  includes: a scheduling unit  321 , for preparing, for the acquisition of a web page, a schedule based on the user profile and the web page acquisition request that are received from the request acceptance unit  310 ; and a web page acquisition unit  322 , for obtaining a web page from the web server  230  in accordance with the schedule prepared by the scheduling unit  321 . Subsequently, a web page source obtained by the web page acquisition unit  322  is stored in a web page archival database  350 . 
   The transmission control unit  330  includes: a notification unit  331  for using E-mail to notify a user  120  that a desired web page has been obtained; a link processor  332 , for changing a link for a web page stored in the web page archival database  350 ; and an ftp/http transmitter  333 , for transmitting, to the user  120 , a web page for which the link has been changed. 
     FIG. 6  is a flowchart for explaining the schematic operation of the web page acquisition server  210  in this embodiment. As the initial condition, the user profile has been transmitted to the provider  110 , and is being stored and managed in the user management database  340  by the profile manager  311 . A plurality of users  120 , who receive the Internet connection service from the provider  110 , have accessed the provider  110  using their user terminals  220 , and have transmitted their user profiles and web page acquisition requests. 
   In  FIG. 6 , first, the request manager  312  of the request acceptance unit  310  receives a web page acquisition request and performs a request integration process, while adding the information for the user profile managed by the profile manager  311  (step  601 ). During the request integration process, web page acquisition requests received from multiple users  120  are collected, and a list of the web pages that are to be obtained (hereinafter referred to as an acquisition list) is prepared. At this time, overlapping requests are combined to form a single entry, so that an acquisition list wherein there are no overlapping requests can be prepared. The overlapping requests are integrated because when a target web page must be obtained only once for multiple users  120  who have submitted web page acquisition requests, the load imposed on the web page acquisition server  210  can be reduced. Since the web page acquisition requests are input at arbitrary times from the multiple user terminals  220 , at a predetermined time a lock is applied to the acceptance of web page acquisition requests, and the request integration process is performed. 
     FIG. 7  is a diagram for explaining an example for the integration of two web page acquisition requests and the preparation of an acquisition list having no overlaps. In  FIG. 7 , for each web page that is to be acquired, the name of a user who has requested the acquisition of a web page, the download time, the URL, the acquisition depth and the time limited period for the acquisition are entered in an acquisition list  703 . According to the format shown in  FIG. 7 , the above data are entered as follows.
 [user name]|download time|URL|acquisition depth|time limited acquisition period 
   In  FIG. 7 , in a web page acquisition request  701  submitted by a user  120  having the user ID “01” (hereinafter referred to as [user 01]), www.aaa.co.jp and www.bbb.co.jp are the designated web page URLs that are to be obtained. And in a web page acquisition request  702  submitted by a user  120  having a user ID “02” (hereinafter referred to as [user 02]), www.aaa.co.jp and www.ccc.com are designated as the URLs for the web pages that are to be obtained. In other words, in the web page acquisition requests  701  and  702  there are overlapping requests for www.aaa.co.jp. And when the acquisition list  703  is prepared by integrating these requests  701  and  702 , the user 01 and the user 02 are written in the user name field for the www.aaa.co.jp record. Since the request submitted for the user 02 is that the acquisition of the web page for www.aaa.co.jp be performed at the second level, while the request for the user 01 is that the acquisition be performed at only the first level, the deeper level, i.e., the second level, is written in the depth field in the list  703 . And since a time limited acquisition period is designated for neither user 01 nor user 02, an appropriate time can be selected for the downloading of the web page source. Similarly, information obtained from the web page acquisition request  701  is written in each field of the www.bbb.co.jp record, and information obtained from the web page acquisition request  792  is written in each field of the www.ccc.com record. The request manager  312  of the request acceptance unit  310  employs the acquisition list  703  to prepare a table indicating the correlation of the URL of a web page and the user  120  who requests the web page, and transmits the table to the transmission control unit  330 . 
     FIG. 8  is a diagram for explaining the table prepared using the acquisition list  703  in  FIG. 7 . In  FIG. 8 , a URL and a corresponding user name are entered in the same record for the acquisition list  703 . However, since both users 01 and 02 request the acquisition of www.aaa.co.jp, the users 01 and 02 are entered as user names corresponding to the URL. In  FIG. 8 , an asterisk “*” following a URL represents a web page that is obtained by tracking the links leading from the web page of the pertinent URL a distance that is equivalent to the number of asterisks. For example, www.aaa.co.jp/* in the second record represents a correlation between the user and a web page obtained by tracking the links, extending from the web page www.aaa.co.jp, a distance that is equivalent to one level. 
   In  FIG. 6 , the scheduling unit  321  of the web page acquisition/archiving unit  320  employs the acquisition list  703  to prepare a schedule for the acquisition of a web page (step  602 ). The schedule is prepared by applying a predetermined scheduling rule for the acquisition list  703 . A variety of rules can be employed as scheduling rules, in accordance with the contents of a service provided by a system, but the basic rules that can be set include, for example,
     1. the acquisition of a first web page for which an early download time has been set; and   2. the acquisition of a web page to be performed within a time period during which the volume of the communication traffic is small.   

   Further, a rule according to a special mode, such as a rule according to which, when the web server  230  is not active, an acquisition process is retried a predetermined time later, can be employed with the preceding rules. 
     FIG. 9  is a diagram for explaining an example schedule that is prepared using the acquisition list  703  in  FIG. 7 , and that is based on the scheduling rules 1 and 2. In  FIG. 9 , for each web page that is to be obtained, the URL of the web page, the time the web server  230  is to be accessed, the acquisition depth, and the time limited acquisition period are entered in a schedule  901 . And in accordance with the format in  FIG. 9 , data are entered as follows.
 URL|access time|acquisition depth|time limited acquisition period 
   According to the schedule  901  in  FIG. 9 , the web page source for www.aaa.co.jp is to be obtained at ten o&#39;clock in the morning, the web page source for www.ccc.com is to be obtained at eleven o&#39;clock, and the web page source for www.bbb.co.jp is to be obtained at two o&#39;clock in the afternoon. The time limited acquisition period is designated for www.ccc.com and www.bbb.co.jp; the web page source for www.ccc.com should be continued until March 7th, and the web page source of www.bbb.co.jp should be obtained during the period between March 5th and March 7th. In the acquisition list  703 , the acquisition of the web page source of www.ccc.com is scheduled first, even though the for www.bbb.co.jp is earlier than the downloading time for www.ccc.com. This is because, since www.ccc.com is present on the web site  130  in the United States, the web page source should be obtained for a time zone during which the network line in the United States is not busy. 
   In  FIG. 6 , the web page acquisition unit  322  of the web page acquisition/archiving unit  320  obtains a target web page from the web server  230  in accordance with the schedule  901  prepared by the scheduling unit  321  (step  603 ). At this time, in order to obtain web pages at two levels or more, each time a link is traced the equivalent of one level, a new URL for a web page at the pertinent linking destination is obtained. Therefore, the schedule  901  must be recurrently prepared by adding a newly acquired URL. In other words, the schedule  901  is dynamically updated whenever a web page is acquired. 
     FIG. 10  is a flowchart for explaining the process for the recurrent preparation of the schedule  901  while a web page is obtained. In  FIG. 10 , first, based on the acquisition list  703  that is prepared by the request acceptance unit  310 , the scheduling unit  321  prepares the schedule  901  to obtain a web page (step  1001 ). Thereafter, the web page acquisition unit  322  examines the schedule  901  to determine whether there is a remaining unprocessed URL. If an unprocessed URL is present, the web page of the pertinent URL is obtained in accordance with the schedule  901  (steps  1002  and  1003 ). Then, in the schedule  901 , the depth for the acquisition of the pertinent web page is examined to determine whether the source at the linking destination for the web page should be obtained (step  1004 ). If the source need not be obtained, program control returns to sep  1002 . However, if the source must be obtained, the URL at the linking destination is added to the acquisition list  703  (step  1005 ). Then the schedule  901  is updated, and program control is thereafter returned to step  1002  (step  1006 ). 
   When at step  1002 , it is determined that all the URLs in the schedule  901  have been obtained, the processing is terminated. The thus obtained web pages are sequentially stored in the web page archival database  350 , which is used for the web page archival database  350  that is used to store web pages that are obtained by constructing a virtual tree structure. Using the virtual tree structure, the directory structure of the web server  230  can be reproduced. 
     FIG. 11  is a diagram for explaining the virtual tree structure of the web page archival database  350 . In  FIG. 11 , a domain name is entered in a root node  1101 , and the names of directories for the web server  230  are entered in child nodes  1102  to  1108 . The HTML file and the image file for the individual web pages have the same structure as the file structure for the web server  230 , and are stored in corresponding directories. 
   In the example in  FIG. 11 , two directories (nodes  1102  and  1103 ) and one file (index.html) are positioned under www.aaa.co.jp of the root node  1101 . And according to the URL form, these entities are represented by www.aaa.co.jp/services/, www.aaa.co.jp/software/ and www.aaa.co.jp/index.html. In addition, two directories (nodes  1104  and  1105 ) and one file (index.html), which are positioned under the services directory for the node  1102 , are represented by www.aaa.co.jp/services/e-business, www.aaa.co.jp/services/it-consl/ and www.aaa.co.jp/services/index.html. 
   Since according to the file system rule, a domain name such as www.aaa.co.jp, which is used as a URL, is not permitted to be used as a file name, a unique ID that can be used as a file name is provided for the domain name when the web page source is transmitted to the user  120 . A pair consisting of an ID and the corresponding domain name is registered in the table. And since there is high probability that the image file names in the web pages may overlap, a unique ID is also provided for the image file name, and the resultant image name is located in a directory that has the image format as its directory name. The paired ID and image file names are also registered in the table. 
     FIG. 12  is a diagram showing an example table prepared for the tree structure in  FIG. 11 . 
   In  FIG. 6 , when a web page is obtained upon the receipt of a specific web page acquisition request, the notification unit  331  of the transmission control unit  330  transmits an E-mail to the user  120  who issued the web page acquisition request to notify the user  120  that the web page has been acquired (step  604 ). Thereafter, the user  120  confirms the download time, or the E-mail for the notification of the web page acquisition, and accesses the provider  110  to request that the web page source be downloaded. Then, after the web page acquisition server  210  of the provider  110  has received a download request from the user  120 , the profile manager  311  of the request acceptance unit  310  reads the profile of the user  120  from the user management database  340 , and transmits to the transmission control unit  330  the profile, along with the download request. 
   The operation performed by the transmission control unit  330  differs when data division and transmission is designated in the user profile and when it is not designated. Hereinafter, an explanation will be first given for a case wherein data division and transmission are not designated, and second for a case wherein these two operations are designated. 
   In  FIG. 6 , the link processor  332  of the transmission control unit  330  reads a pertinent web page source from the web page archival database  350 , and performs the link process (step  605 ). During the link process, the link for the web page is changed from an absolute (dynamic) one, based on the URL, to a relative (local) one in the tree structure for the web page archival database  350 . When a pertinent web page source has been transmitted to the user terminal  220 , and when the user  120  is to track the link of the web page, if the dynamic link is unchanged, access of the web site  130  would occur across the Internet  200 , and as a result, the above linking process is required to maintain the local operation. 
   The link processor  332  examines the table (see  FIG. 8 ), which is prepared by the request manager  312  of the request acceptance unit  310  and which describes the correlation between the URL of the web page and the user  120  who requested the web page, and determines whether there is another user  120  who has also requested the target web page source for the linking process. If no other user  120  has requested the pertinent web page source, the web page source is deleted from the web page archival database  350 , and the record concerning the web page source is deleted from the table. 
     FIG. 13  is a diagram showing the state of the table  801  in  FIG. 8  wherein all the web page sources requested by the user 01 have been downloaded. In  FIG. 13 , since the web page source for www.aaa.co.jp that has been downloaded by the user 01 is also requested by the user 02, the record for this web page source is not deleted. Accordingly, the web page source is retained in the web page archival database  350 , and the user ID for the record is merely changed to “02”. As for the www.bbb.co.jp/news and www.bbb.co.jp/news/*, both of which were requested only by the user 01, after the web page sources have been downloaded by the user 01 the pertinent records is deleted from the table  801 . Accordingly, the pertinent web page sources are deleted from the web page archival database  350 . 
   If a download request is not issued by the user  120 , even after the downloading time has elapsed, various methods can be employed to handle the pertinent web page source. For example, the web page source may continue to be held until another download request is issued by the user  120 , or it may be deleted after a predetermined period of time has elapsed or immediately after the download time has elapsed. These methods can be designated by employing the user profile. 
     FIG. 14  is a diagram showing the status of the linking process when downloading up to the second level of the web page for www.aaa.co.jp is requested. In  FIG. 14 , the web page for www.aaa.co.jp/index.html and web pages for www.aaa.co.jp/services/index.html and www.aaa.co.jp/software/index.html, which are two link destinations written in the web pages, are downloaded. During the linking process, the table in  FIG. 12  is examined to change the dynamic link in www.aaa.co.jp/index.html to a local link. And in the example, “http://www.aaa.co.jp/services/” is changed to “site12/services/index.html”. On the other hand, the web pages at the link destinations for the web pages www.aaa.co.jp/services/index.html and www.aaa.co.jp/software/index.html, i.e., the web pages in the directories (the nodes  1102  and  1103  in  FIG. 11 ) www.aaa.co/jp/services/ and www.aaa.co.jp/software/, are not downloaded, so that the dynamic link is not changed. In the above example, “http://www.aaa.co.jp/services/e-business/” and “http://www.aaa.co.jp/services/it-consl/” are not changed. 
   During the linking process, the web page for site12, which corresponds to www.aaa.co.jp., is displayed by using the browser in the user terminal  220  that has downloaded, up to the second level, the web page for www.aaa.co.jp. When the link destinations are called, the web pages downloaded with the web page for site12 are displayed. That is, a local operation is performed. To call a link destination that is further distant from the second level, the user terminal  220  is connected to the Internet  200  to permit the pertinent web site  130  to be accessed. 
   In  FIG. 6 , when the linking process has been performed, the ftp/http transmitter  333  of the transmission control unit  330  archives the web page source obtained after the linking process (converts the web page source into a library file), and transmits the resultant web page source to the user  120  (step  606 ). 
     FIG. 15  is a diagram showing the tree structure of a web page source transmitted to the user  120 . In  FIG. 15 , the tree structure is shown for a case wherein the user  120  that has the user ID “01” downloads several web page sources, including site12, which corresponds to www.aaa.co.jp. The web page source for site12 is downloaded up to the third level. And the directory structure used for storing the web page sources in the web page archival database  350  is used unchanged, except that the domain names are replaced by unique IDs. Furthermore, the web page sources to be transmitted to the user  120  includes all the files contained in the directories in the tree structure in  FIG. 15 . When data division and transmission is designated in the user profile, after the web page source downloading request has been received from the user  120 , an examination is performed to determine whether or not data division and transmission is required. And if it is determined data division and transmission are required, they are performed. 
     FIG. 16  is a flowchart for explaining the operation performed by the transmission control unit  330  when data division and transmission is designated. In  FIG. 16 , the transmission control unit  330  receives, from the request acceptance unit  310 , the downloading request submitted by the user  120 , along with the profile of the user  120  (step  1601 ). Then, a check is performed to determine whether the size of the data for the web page source that is to be transmitted exceeds the maximum transmission size (step  1602 ). If the size of the data for the web page source does not exceed the maximum transmission size, as in the operation in  FIG. 6 , the linking processor  332  changes the links of the web page sources, and the ftp/http transmitter  333  transmits the pertinent web page source to the user  120  (steps  1603  and  1604 ). 
   However, if the size of the data for the web page source exceeds the maximum transmission size, the web page source is divided into data files that are not larger than the maximum transmission size for the user terminal  220 . At this time, in order not to discontinue the link, the data are divided so as to maintain to the extent possible the connection along the depth. And the list of the obtained data files (file list) is prepared (step  1605 ). Since the target for the division process is the tree structure of the web page sources in  FIG. 15 , the obtained data files are parts of the original tree structure. Thereafter, a check is performed to determine whether there is an unprocessed data file in the file list (step  1606 ). If an unprocessed data file is present, the link processor  332  performs the linking process for the data file (step  1607 ), and the resultant data file is archived and transmitted to the user  120  (step  1608 ). The processes at steps  1607  and  1608  are then performed for the unprocessed data file in the file list. And when all the data files have been transmitted to the user  120 , the processing is terminated (step  1606 ). When a plurality of data files have been received by the user terminal  220 , they may be maintained unchanged, or they may be assembled and used to form a single file. If a single file is obtained in this fashion, the linking will not be discontinued, even when the file is used as a local file by the user terminal  220 . 
   As is described above, the user  120  can collectively download, from the provider  110 , the data files for desired web pages, and an access request need not be transmitted to individual web sites  130  in order to browse the pertinent web pages. Further, at this time, even when downloading a web page source, data are exchanged only between the user terminal  220  and the web page acquisition server  210 , and no transmission of data occurs between the web server  230  and the web page acquisition server  210 . Thus, there is a considerable reduction in the time the user  120  must wait before being able to browse the web page. The provider  110  accepts in advance a web page acquisition request from the user  120 , and to acquire a web page, accesses the web server  230  in a time period during which communication traffic across the network is not heavy. Further, web page acquisition requests issued in common by multiple users  120  can be collectively coped with by the performance of a single access of the web server  230 . Therefore, the load imposed on the server of the provider  110  can be reduced considerably. 
   It is to be understood that the present invention, in accordance with at least one presently preferred embodiment, may be implemented on at least one general-purpose computer running suitable software programs. It may also be implemented on at least one Integrated Circuit or part of at least one Integrated Circuit. Thus, it is to be understood that the invention may be implemented in hardware, software, or a combination of both. 
   If not otherwise stated herein, it is to be assumed that all patents, patent applications, patent publications and other publications (including web-based publications) mentioned and cited herein are hereby fully incorporated by reference herein as if set forth in their entirety herein. 
   Although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be affected therein by one skilled in the art without departing from the scope or spirit of the invention.