WO1998024027A1

WO1998024027A1 - Web cache memory device and client apparatus utilizing the same

Info

Publication number: WO1998024027A1
Application number: PCT/JP1996/003448
Authority: WO
Inventors: Kazumichi Yamamoto; Yukio Umetani; Norihiro Suzuki; Muneaki Yamaguchi
Original assignee: Hitachi, Ltd.
Priority date: 1996-11-25
Filing date: 1996-11-25
Publication date: 1998-06-04
Also published as: JP4130849B2

Abstract

A cache structure of a World Wide Web (WWW) client apparatus for improving utilization efficiency and reducing access time to information. A cache is constituted in an HDD or DVD-RAM by the control of a Web cache program and a copy of retrieved information is stored in it. A directory of the cache is managed by a Web cache management table, and control is made so that the entries necessary for the cache contents and the management table are stored before the DVD-RAM is removed from the apparatus. The client operation can be smoothly continued by loading the DVD-RAM to another client apparatus, or if an information provider stores the information in the Web cache from and provides it, the information can be browsed by the same URL as the WWW access.

Description

Specification

Web cache storage device and browsing device using it

The present invention relates to a client system such as a browsing device or a personal computer that receives a World Wide Web (WWW) service. In particular, by keeping a copy of the information obtained from the network and displaying the copy in the second and subsequent accesses, the time required for display and the like can be reduced, and the load on the network can be reduced. Reducing cache mechanism. It also relates to pre-reading and caching information that is likely to be viewed by a user in advance. In addition, the present invention relates to a process for removing the storage medium when the cache is configured as a removable storage medium. Background art

The World Wide Web (WWW) service via the Internet has recently attracted public attention as a typical example of the Internet. A home personal computer can be connected to the Internet via a telephone line, and a WWW browsing program can be operated to retrieve and view publicly available information from around the world. In this case, it may take some time before information can be actually browsed after specifying the information to be obtained due to lack of bandwidth of the communication line. In order to hide this delay time, the information once viewed is stored in a secondary storage device, such as a hard disk drive, and a copy is taken out from the secondary storage device for the second and subsequent browsing. , Methods for configuring cache storage for browsing information are known.

Generally, when information is taken in via a network, delay time becomes a problem. A method of hiding this delay time using a cache memory is disclosed in Japanese Patent Application Laid-Open No. Sho 62-63555 filed in Japan.

In addition, although the point of the invention lies in means for guaranteeing the validity of the cache, a method of improving the efficiency by using the cache for information access via a network is disclosed in Japanese Patent Application Laid-Open No. 63-16367. It is disclosed in Japanese Patent Application Publication No. If you use a WWW browsing program and a browsing device with a cache, you can hide the access delay time for the same information from the second time on.

However, if the user uses another browsing device, it is not always possible to benefit from this effect. Assuming that there are two browsing devices with the same specifications, and the user who browsed the first information moves to the second browsing device and tries to browse the same information, There is no guarantee that the information will be cached on the second viewing device. From the user's point of view, if the information has been viewed once, the information should be displayed immediately in the second browsing, even if another browsing device is used: This is the first problem to be solved.

When browsing the WWW, it is common to follow (jump) information one after another using hyperlinks. A character string with a hyperlink is called an anchor. When jumping with a hyperlink by specifying an anchor, network access delay time is required if the information of the jump destination is the first to be viewed. If the connection is made using a low-speed line such as a telephone line, comfortable browsing may not be possible. This is the second problem to be solved by the present invention. In order to solve the first problem, a storage device that records information on a removable storage medium is used. When removing this storage medium, there is a write operation that must be completed before removing. When the user operates the eject button on the storage device, the completion of the writing process is not always guaranteed. This is the third problem to be solved by the present invention. Disclosure of the invention

In order to solve the first problem, the use of a storage device for the user to record the Canon Tsu Shi out _3-up may be set to cormorants by Gerhard the possible portable storage medium ί information in the book of your browsing information A cache may be configured in this storage medium. If the access time of this storage device is slower than other secondary storage devices, for example, a hard disk drive, a cache is configured in combination with them. When removing this storage medium or ending the browsing program, make sure that all information stored in the cache, including other secondary storage devices, has been written to the storage medium. The user can smoothly resume the browsing work by carrying this storage medium. In extreme cases, any information recorded on this storage medium can be browsed by a browsing device that is not connected to the network.

In order to solve the second problem, information that is likely to be specified by the user is pre-read and stored in the cache. It is highly likely that the user will point to one of the anchors embedded in the browsing information.

Among them, it is highly likely that the anchor currently displayed on the display screen is indicated, and information on the hyperlink destination of the displayed anchor is stored in the cache. In order to solve the third problem, when the user operates the eject button, instead of immediately ejecting the storage medium, the system starts a routine for performing necessary write processing, and the write processing is started. After the completion, the system issues an instruction to eject the storage medium or a signal indicating permission to eject the storage medium to the storage device.

Specifically, in the terminal device, a storage medium for storing information from the network as cache data is made freely attachable and detachable. Further, the terminal device is provided with means for recording the information as cache data in a secondary storage device other than the storage medium. Further, there is provided means for recording the cache data on the recording medium as cache data that can be used in another terminal device. Further, a first directory table is stored in the storage medium, which associates an address of the information on the network with an address of the information stored on the storage medium as cache data on the storage medium. Corresponds to an address on the network of the information provided in the medium and an address of the information stored as cache data in the secondary storage device on the secondary storage device. A second directory table to be attached is provided in the secondary storage device, and the first directory table and the second directory table are stored in the information network. The address is created by merging the above address as a key, and includes a field for an address on the storage medium and a field for an address on the secondary storage device. Cache using directory table 3 Have a means to search for data.

Also, the present invention relates to a method of accessing information from a terminal device used by being connected to a network, wherein a copy of information from the network is freely detachable from the terminal device. And the terminal writes the information When accessing the information, first, there is a step of accessing the storage medium, and a step of obtaining the information via the network when the storage medium does not have the information.

Further, the recording medium is a recording medium that can be freely attached to and detached from the terminal device, wherein the recording medium is a portion in which a program to be executed by the terminal device is recorded, and the program is connected to the terminal device. A part for recording information from the network as cache data is provided. Alternatively, the recording medium is a recording medium that can be freely attached to and detached from the terminal device, and the recording medium is capable of freely attaching and detaching information from the network to which the terminal device is connected to the terminal device. It has a part that records a program to be recorded as cache data on a simple recording medium.

A method for obtaining information from a terminal device for obtaining information from a network, the method comprising: prioritizing an anchor displayed on a display screen of the terminal device; Then, according to the priority, a step of obtaining information on the link destination indicated by the anchor via the network is provided. Furthermore, a step of alternately changing the display attributes of the anchors whose information has been obtained before the user specifies the anchor, the display attributes of the anchors whose obtaining has been completed, and the display attributes of the anchors whose obtaining has not begun. To have

A method for accessing information from a terminal device that obtains information from a network, the method comprising: prioritizing an anchor displayed on a display screen of the terminal device; A step of obtaining information on a link destination indicated by an anchor via the network according to the priority, and a step of obtaining the information on a storage medium that can be freely attached to and detached from the terminal device. Recording the information from the network as cache data.

Also, in a storage device that records information on a removable storage medium, when a user gives an instruction to eject the storage medium to the storage device, the storage device and a system to which the storage device is connected. If there is information to be recorded in the storage medium in the storage medium, a write process is performed on the storage medium, and after the write process is completed, a command to discharge the storage medium from the system to the storage device is issued. To do.

In addition, a storage device that records information on a removable storage medium and another secondary storage device are combined and used as a cache storage for storing a copy of information obtained via a network. In a system for controlling cache storage by a method of retaining the cache storage in a storage medium, when a user issues an instruction to move the storage medium to the storage device, the cache storage is controlled. If there is information to be recorded in the storage medium in the storage medium, a write process is performed on the storage medium, and after the write process is completed, the system issues a storage command / discharge command to the storage device. Make sure to give emission permits. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram illustrating a logical configuration of a program or the like in a viewing device, FIG. 2 is a diagram illustrating a hardware configuration of a browsing device, and FIG. 3 is a browsing according to the present invention. FIG. 4 is a diagram for explaining an example of use and effects of the device, FIG. 4 is a diagram for explaining control of the entire Web cache, and FIG. 5 is a diagram for explaining a management algorithm of the Web cache. FIG. 6 is a diagram illustrating the entire web cache management table, and FIG. 7 is a diagram illustrating the web cache management table. FIG. 8 is a diagram illustrating a web cache management table, FIG. 9 is a diagram illustrating a web cache management table, and FIG. 10 is a diagram illustrating a hard disk drive. FIG. 11 is a diagram for explaining a web cache management table on a disk. FIG. 11 is a diagram for explaining a web cache management table on a DV D-RAM. FIG. FIG. 13 is a diagram illustrating a pre-read list, FIG. 13 is a diagram illustrating a display screen of a browsing program and a pre-fetch process, and FIG. 14 is a diagram illustrating a display screen of a browsing program and a pre-fetch process. FIG. 15 is a diagram for explaining the procedure of disc ejection, FIG. 16 is a time chart relating to the disc ejection process, and FIG. 17 is a diagram for explaining the procedure of disc ejection. Fig. 18 shows the disc ejection process. Taimuchiya is one bet. BEST MODE FOR CARRYING OUT THE INVENTION

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

First, the hardware configuration of the browsing device and the connection relationship with the network will be described with reference to FIG. The mouth area network (hereinafter abbreviated as LAN) 2 includes a server device that provides services such as a world wide web (abbreviated as web hereinafter) 2 3. A browsing device 24, 25, 26, which is a web service client, is connected. The number of server devices 23 and browsing devices 24, 25, and 26 connected to LA 2 is an example, and is not limited to this. LAN 2 is connected to Internet 3. Another LAN 2 is connected to the Internet 3, and a server device 23 is connected to this. The number of LANs 2 connected to the Internet 3 is not limited to this, but is not limited to the LAN 2 and the Internet in this specification. Group 3 is sometimes called a network. The browsing devices 24, 25, and 26 can receive a Web service from any of the server devices 23 via the LAN 2 and the Internet 3. The browsing devices 24 and 25 are examples of the appearance.

The browsing device 26 illustrates the hardware configuration. The browsing device 26 includes a system bus 30, a CPU 36, a system control device 28, a main memory 29, a hard disk drive (hereinafter abbreviated as HDD) 32, and a DVD-RAM drive 3. 3, network adapter 27, input / output device 31, graphics adapter 34, monitor device 35, keyboard 88, mouse 89, sound generator 90, and speaker 91. The CPU 36 is connected to the main memory 29 and the system bus 30 via the system controller 28. The system bus 30 is connected to a system controller 28, HDD 32, DVD-RAM drive 33, network adapter 27, input / output device 31, and graphics adapter 34. D VD—RAM drive 33 mounts DVD—RAM disk 37, and writes, reads, and erases information from DVD—RAM disk 37. DVD-RAM disk 37 can be removed from DVD-RAM drive 33. A monitor 35 is connected to the graphics adapter 34. The monitor device 35 in this specification is, for example, a display device equipped with a CRT. Network adapter 27 is connected to LAN2. The keyboard 88 and the mouse 89 are connected to the input / output device 31. The user can use the keyboard 88 and mouse 89 to issue a command to the browsing device. The sound generator 90 is connected to the input / output device 31, and the speed 91 is connected to the sound generator 90. This allows the user to listen to the sound I can hear my voice.

Next, with reference to Fig. 1, the configuration of a program and the like operating in the browsing device and an outline of the operation will be described. The browsing device 1 provides the same functions as the browsing devices 24, 25, and 26. It is assumed that the browsing device 1 is connected to the LAN 2, and the LAN 2 is connected to the Internet 3. An operating system (hereinafter abbreviated as O S) 6 is operating in the browsing device 1, and controls the entire browsing device 1.閲覧 The browsing program 4 and the web cache program 5 operate under the control of S6. DV D—RAM drive 33 File system 8 is configured on DV D—RAM disk in 3. The file system 9 is configured on the HDD 32. A main cache area 10 is secured in the main memory 29. Network connection 7 communicates with LAN 2.

The browsing program 4 receives a URL (Uniform Resource Locator) that the user uses a keyboard 88 or a mouse 89, and provides a web service provided by the server device 23. Information is obtained from the computer, a window as shown in FIG. 13 is displayed on the screen of the monitor device 35, and the obtained information is displayed in a form that can be understood by the user. Here, the URL is an address that uniquely determines the location of information such as text, images, and sounds provided through the Internet 3. The window shown in FIG. 13 will be described later. The user can browse various information provided through the Internet 3 by inputting a desired URL in the window displayed by the browsing program 4.

In the simplest form of the program configuration of the browsing device 1, all URL requests are passed directly to the network S6, and the LAN requests are sent one by one via the network connection unit 7. 2. Information will be fetched from the server device 23 via the Internet 3. On the other hand, when the bandwidth of LAN 2 and Internet 3 and the connection between them are insufficient, that is, when the network becomes busy, a URL request is issued and the specified information is sent back. The delay time until the response is increased, and the response is reduced. In some cases, the delay time may be large enough to cause a timeout in browsing program 4, which may hinder user productivity. In order to reduce this delay apparently and to reduce the load on the network, the information once browsed is stored in a cache in the browsing device. The method of retrieving information from the cache instead of retrieving it via Internet 3 is often used. This cache is generally configured in the finalization system 9 of the HDD 32. In the present specification, such a cache is referred to as a web cache.

One of the features of the present embodiment is that the Web cache is configured not only in the HDD 32 but also in the file system 8 of the DVD-RAM disk in the DVD-RAM drive. Also, an area may be secured on the main memory 29, and a Web cache may be configured there. In order to integrate and manage such physically distributed Web caches, a Web cache program 5 will be provided.

The web cache program 5 includes a web cache control unit 13, a pre-read list 14, and a web cache management table 15. The pre-read list 14 will be described later with reference to FIG. The web cache management table 15 includes main memory web cache management fields 16, HDD web cache management fields 17, DVD—RAM web. There is a cache management field 18. The details of the web cache management table 15 will be described later with reference to FIGS.

In the file system 9 on the HDD, a Web cache management table 21 and a Web cache area 22 are secured. The information stored in the Web cache of the HDD is written as a file in the Web cache area 22. The list of contents stored in the web cache area 2 2 is reflected in the web cache management field 17 of the HDD D in the web cache management table 15 and can be viewed. When the program 4 is completed, a copy of the contents of the web cache management field 17 of the HDD is stored in the web cache management table 21.

The DVD cache management table 19 and the WEB cache area 20 are secured in the file system 8 on the DVD—RAM. DVD—Information stored in the web cache of the RAM is written to the web cache area 20 as a file. A list of the contents stored in the web cache area 20 is reflected in the web cache management table 15 DV D—RAM web cache management field 18 in RAM, but the browsing program When step 4 is completed, a copy of the contents of the DVD-RAM web cache management field 18 is stored in the web cache management table 19. If the DVD-RAM disc is ejected during the operation of the browsing program 4, the contents of the DVD-RAM web cache management field 18 at that time are stored in the W DVD—RAM disc is ejected after being copied to the eb cache management table 19. Also, the time at that time may be written to the DVD-RAM disk immediately before the ejection.

A web cache area 10 is secured on the main memory 29. The list of contents stored in the web cache area 10 is reflected in the web cache management field 16 of the main memory of the web cache management table 15. At the end of browsing program 4, Web cache area 10 is opened.

When the control unit 13 receives the URL access request 11 from the browsing program 4, the control unit 13 searches the pre-read list 14 and the web cache management table 15 to find the main memory, the HDD, and the like. DVD—Checks whether a copy of the specified information is stored in one of the web caches in RAM. In this specification, the presence of specified information in one of the Web caches is called a hit, and the absence of the specified information is called a mistake. In the case of a hit, check which Web cache and which file the file belongs to, fetch the file, and give the contents of the fetched file as a response message 12 to the viewing program 4. In the case of a miss, the URL access request message 11 1 is passed to OS 6. The OS 6 accesses the network using the network connection unit 7, extracts information from an appropriate server device, and provides the information to the control unit 13. The control unit 13 gives the content of the information received as a response message 12 to the browsing program 4. At the same time, the information is stored in the Web cache. The above is the outline of the operation of the control unit 13. The detailed flow will be described later with reference to FIGS. In the case of a hit, it is not necessary to obtain information via a network, so the delay time from the user's specification of the URL to the display of the information can be reduced. In this way, the Web cache program 5 assists the browsing program 4 in acquiring the data and shortens the time required for the acquisition. This is a common feature of browsing devices with a cache.

The features of the browsing device to which the present invention is applied will be described with reference to FIG. User review Assume that the user is browsing the Web service by attaching the D VD—RAM disk 37 to the D VD—RAM drive 33 of the viewing device A 24. The information browsed by the user is stored in the Web cache area configured in the DVD-RAM disk 37 by the operation of the Web cache program 5. Assume that the user stops browsing on the browsing device A 24 for some reason, moves to the browsing device B 25, and resumes browsing. At this time, the user takes out the DVD-RAM disk 37 from the browsing device A and mounts it on the DVD-RAM drive 33 of the browsing device B25. Then, it is assumed that the information browsed by the browsing device A is confirmed again. In this case, the same information is not necessarily stored in the web cache configured in the HDD 32 of the browsing device B 25, but the D VD— The same information is surely stored in the Web cache in the RAM disk 37. The Web cache program of the browsing device B 25 retrieves information from the DVD-RAM disk 37 and gives it to the browsing program 4. Therefore, the delay time from the URL specification to the information display can be reduced. This effect is equivalent to the case where the user continues browsing work with the browsing device A24. In this way, a user can carry his or her own web cache environment on a DV D-RAM disk 37.

Also, a plurality of pieces of information provided by the information provider on the network using the server device 23 are stored in the Web cache of the DVD-RAM disk 38, and mailed to the user, for example, by mail. You can do it. The user who receives it attaches it to the DVD-RAM drive 33 of the viewing device and views it. Even if the information has never been viewed by the user, if the information provider stores the information in the Web cache of the DVD-RAM disk 38, the information is taken from the network. Information from this web cache Out Shi user can that can ₌ this and to browse take is not necessary to be aware of the fact that the desired information is in the D VD- R AM disk 3 8, in the normal browsing the like, attached to the information All you have to do is specify the URL you are using.

As described above, in the browsing apparatus to which the present invention is applied, a Web cache is also configured on a removable medium such as a DVD-RAM disk, so that the cache is provided for each user. It is possible to carry the environment. As a result, even if the browsing device is moved, the time required for browsing can be shortened and productivity can be improved. Also, by obtaining a DVD-RAM disk with a Web cache containing information from information providers, etc., the information to be viewed for the first time is also on the DVD-RAM disk. Similarly, the time required for browsing can be shortened without being aware of the situation.

The outline of the overall processing flow of the control unit 13 will be described with reference to FIG. Event 39, 40, Steps 41 to 53 Flow for hit / miss judgment of the Web cache and processing at the time of miss, and processing for prefetching described later. Will be described. The process when a DVD-RAM disc 37 is inserted into the DVD-RAM drive 33 and inserted into the DVD-RAM drive 33 with a flow consisting of the event 54 and the steps 55 to 57 will be described. The process when the DVD-RAM drive 37 is taken out from the DVD-RAM drive 33 in the flow consisting of the event 58 and the steps 59-62 will be described. Also, although not a flow, the relationship between the web cache management table processing routine 63 for operating the web cache management table 15 and each of the above flows is illustrated. In FIG. 4, the solid line with an arrow indicates the flow of processing, and the dotted line indicates the request relationship of the processing from the processing step to the Web cache management table processing routine 63. A flow consisting of events 39, 40 and steps 41 to 53 will be described. This flow is triggered by the occurrence of one of two events 39, 40. First, event 39 occurs when the user specifies a URL for the browsing device. This corresponds to the information that the user wants to view specified by the URL. Event 40 is generated by a read-ahead request by browsing program 4 described later. The word browser at event 40 in Figure 4 is synonymous with browsing program 4.

Briefly explaining this look-ahead processing, for an anchor that is likely to be specified by the user in the near future, information on the hyperlink destination is pre-fetched and stored in the Web cache. It is. Here, the en force is a part that exists in the browsed information that can be displayed and is associated with other information, and the association is determined by URL. An anchor is often designated using a mouse 89. When the anchor is specified, the browsing process of the information that specifies the URL embedded in it is started. In this way, browsing by specifying an anchor is called a hyperlink. The look-ahead processing, anchor, and hyperlink will be described later in detail.

Events 39 and 40 have the same effect in terms of the generation of URL access requests, even if they have different origins, and the flow proceeds to step 41. In step 41, a search process is performed on the pre-read list 14 using the URL specified by the events 39, 40 as a search key. The structure of the pre-read list 14 will be described later with reference to FIG.

After that, go to step 42. If the search result in step 41 is a mistake, proceed to step 43. If hit, skip steps 4 3 and 4 4 and go to step 4 5- In step 43, a search process is performed on the web cache management table 15 using the URLs specified in events 39 and 40 as search keys. As indicated by the dotted line, processing is requested to the Web cache management table processing routine 63 from step 43. Web Cache Management Table Processing Routine The search results (from hit cache and main memory, HDD, DVD-RAM, which Web cache is stored) The processing result is returned when the original of the information stored in the file was created (the original creation date and time), and when the original was created was checked (the check date and time). .

Receiving the result, proceed to step 44. If the search result in step 43 is a mistake, proceed to step 52. If it is a hit, go to step 45.

In step 45, the check date and time returned from the Web cache management table processing routine 63 are examined. If the time from the last check date to the present time is less than 24 hours, for example, skip steps 46 and 47 and proceed to step 48. Check If the time from the date and time to the present is 24 hours or more, proceed to Step 46. Here, 24 hours is used as a criterion, but this is only an example for explanation, and it is more convenient that this numerical value can be set by the user.

In step 46, the server device 23 in which the original of the information specified by the URL is stored is accessed through the network, and the creation date and time is confirmed. This is performed to check whether or not the original on the server device 23 has been newly updated, rather than a copy of the information specified by the URL stored in the Web cache. Upon receiving the result, in step 47, if the original on the server device 23 is newer, the process proceeds to step 52. If not, go to step 48.

Here, the processing in steps 52 and 53 which are the jump destinations from steps 44 and 47 will be described.

In step 52, access is made to the server device 23 in which the original of the information specified by the URL is stored through the network, and the corresponding information is obtained. In step 53, the process of storing the information obtained from the network in the Web cache is performed. This Web cache update process will be described later with reference to FIG. Further, the Web cache management table processing routine 15 is requested to update the Web cache management table 15 in association with the Web cache update processing. The Web cache management table processing routine 63 updates the entry information of the specified URL if the entry already exists. If it does not exist, add a new entry.

Then go to step 48. Step 48 is a jump to steps 45, 47 and 53. Determine if this flow was caused by the event 40 caused by the event 39. If triggered by event 39, go to step 49. If triggered by event 40, go to step 50.

In step 49, information is extracted from the Web cache and passed to browsing program 4. In response to this, the browsing program 4 displays information on the screen of the monitor device 35 in a form that can be browsed by the user.

In step 50, the prefetched list 14 is updated to indicate that the specified URL has been prefetched and stored in the web cache. In step 51, the flow ends.

Next, the flow consisting of event 54 and steps 55 to 57 will be described. This flow is performed when the DVD-RAM disk 37 is inserted into the DVD-RAM drive 33 during the operation of the Web cache program 5, and is mounted.

This flow is activated when event 54 occurs. This event is generated by detecting a signal indicating that the DVD-RAM disk 37 is attached to the DVD-RAM drive 33.

In step 55, it is checked whether or not the mounted DVD—RAM disk 37 has a Web cache. If the Web cache is configured, go to step 56. Otherwise, proceed to step 57-In step 56, the web cache management table 19 configured in the file system 8 on the attached DVD-RAM disk 37 will be stored in the web cache. Merge to the web cache management table 15 in the cache program 5. This is done with the URL as the key. This processing is requested to the Web cache management table processing routine 63.

This flow ends in step 57.

Next, a flow including the event 58 and the steps 59 to 62 will be described. This process is performed when the DVD-RAM disk 37 is removed from the DVD-RAM drive 33 while the Web cache program 5 is operating.

This flow is triggered by the occurrence of event 58. This event is generated by detecting an ejection request signal from the DVD-RAM drive 33 of the DVD-RAM disk 37. In step 59, from the entries in the web cache management table 15, the entry with the information about the web cache on the DVD-RAM is extracted, and further, the URL, Extract only the file attributes, DVD—information about the web cache on the RAM. This processing is requested to the Web cache management table processing routine. In step 60, the entry of the web cache management table extracted in step 59 is written to the web cache management table 19 of DVD-RAM. If the information to be stored in the Web cache area 20 of the DVD-RAM has not yet been written, these are also written. This may be the case, for example, where the copying of information to be copied from the web cache area 22 of the HDD to the web cache area 20 of the DVD-RAM is suspended. It also writes the current date and time to indicate when this DVD-RAM disk 37 was removed from control of the web cache program. At this time, the writing time may be written in Greenwich Mean Time, or the time difference between the system reference time and Greenwich Mean Time may be written at the same time. In the former case, the information indicating that the entered time is in Greenwich Mean Time and the time difference between the system reference time and the time may be entered. The information on the time difference between the date and time when this disc was removed and the Greenwich Mean Time will be used next time when this DVD-RAM disc 37 is attached to the browsing device and used as a web cache. Sometimes used. Even if the user moves beyond the time zone, it is possible to check the browsing information from the time difference information and correct the time information such as the date and time. For example, assuming that the last disk removal time was one month ago, the check date and time of all browsing information cached in the DVD—RAM disk 37 is Needless to look at the web cache management table, it turns out that it is more than a month ago. Using this information, for example, the processing in steps 45 can be reduced.

In step 61, a signal is generated to instruct the DVD-RAM drive 33 to eject the 130-108M disk 37. This signal may be a signal for instructing disc ejection or a signal for permitting disc ejection. The details of the disk ejection procedure will be described later with reference to FIGS.

The flow ends in step 62.

Next, the algorithm for managing the Web cache (Web cache management routine) will be described with reference to FIG. In this flow, the information to be browsed is stored in the Web cache, and the result is reflected in the Web cache management table 15 to maintain consistency.

The flow starts at step 64. This flow is also activated by a request from step 43 or step 53 in FIG.

In step 65, the Web cache management table 15 is searched using the URL as a key.

In step 66, based on the result of step 65, if the URL has been hit and the original date and time of creation are the latest and the check date and time are the latest, the process proceeds to step 67. Otherwise proceed to step 68. Here, the date and time when the original was created is the latest when the date and time of the original in the field of information on the web cache on the main memory and the original in the field of information on the web cache on the HDD are used. Confirm by comparing the date and time of creation with the date and time of creation of the original field in the DVD—Information on Web Cache on RAM field. For example, the original on the main memory and that on the HDD have the same In the case of, each check date and time is checked next to determine which is the latest. If the check date and time are the same, it is assumed that the copy on the main memory is the latest. Similarly, the original copy date and time and check date and time are compared, and the latest copy is stored in the web cache (main memory, HDD, DVD—RAM, etc.). If there is the same thing, if the same thing is found, the priority to adopt is the highest in main memory, the HDD is next, the DVD-RAM is next, and the priority is Determine the latest copy. This priority is determined by the access speed, and the priority is given to the one with the faster access speed. If a new medium other than DVD-RAM is adopted as a removable medium and its access speed is faster than that of HDD, the priority will be in the order of main memory, the new medium, and HDD.

If you proceed to step 67, no further cache management is needed and the flow ends here.

In step 68, after the result of step 65, if the URL has been hit and the copy stored in the web cache on the HDD is the latest, go to step 69. move on. Otherwise, go to step 72. In step 69, copy (cache-in) the copy on the HDD to another web cache (on the main memory or on DVD-RAM). Is determined. This is based on the attributes of the corresponding file on the HDD. For example, the criteria are determined based on the size of the file. For example, if the size of the information is less than 500 KB, the size of the information is determined to be small, and the process proceeds to step 70. Otherwise, the size of the information is determined to be medium or higher, and the process proceeds to step 71.

In step 70, a copy of the relevant information on the HDD is copied to the main memory. Copy it to your web cache.

In step 71, the relevant information on the HDD is copied to the DVD cache on the DVD—RAM. Or prepare to copy. This is necessary when writing to the DVD-RAM using the write-back method. This write-back method means that instead of writing files to be written to DVD-RAM one by one, it is necessary to mark each of them as needing to be written. This is a method of writing all marked items to DVD-RAM. The preparation for copying above is the process of adding this mark.

In step 72, if the result of step 65 is met and the URL is hit, and the copy stored in the web cache on DVD-RAM is the latest, go to step 73. move on. Otherwise, go to step 77.

In step 73, it is determined whether or not the copy on the DVD-RAM is copied (cache-in) to another Web cache (on the main memory or on the HDD). This is based on the attributes of the corresponding file in DVD-RAM. For example, the criteria are determined based on the size of the file. For example, if the size of the information is less than 500 KB, the size of the information is determined to be small, and the process proceeds to step 74. For example, if the size of the information is less than 5 MB, it is determined that the size of the information is medium, and the process proceeds to step 75. If it is larger, the size of the information is large, and the process proceeds to step 76.

In step 74, a copy of the relevant information on the DVD-RAM is copied to the Web cache in the main memory.

In step 75, copy the relevant information on DVD—RAM Copy it to the web cache above.

In step 76, since the size is large (for example, 5 MB or more), the information is not stored in the main memory or the HDD, and the flow is terminated. Next, step 77 will be described. Step 77 is a check on the date and time when the result of the URL search was a mistake or the creation date and time of the original on the server device 23 performed in step 46 in FIG. 4, and the original is stored in the Web cache. This is done if more recent than any copy. In these cases, the corresponding information is obtained from the server device 23 on the network in step 52 of FIG. In step 77, the information obtained from the server device 23 on the network is copied to one or more of the web caches (on the main memory, on the HDD, or on the DVD-RAM). Judge whether or not to carry out. For example, the criteria are determined based on the size of the file. For example, if the size of the information is less than 500 KB, the size of the information is determined to be small, and the process proceeds to step 78. For example, if the size of the information is less than 5 MB, the size of the information is determined to be medium, and the process proceeds to step 79. If it is larger, the size of the information is large, and the process proceeds to step 80. If the size of the information is not determined, go to step 81. When the size is not determined, for example, information in a form that can be continuously transmitted from an information source is considered.

In step 78, the obtained information is copied to the Web cache on the main memory.

In step 79, the obtained information is copied to a Web cache on the HDD, and a mark is provided for copying to the DVD-RAM in a light knock manner. In step 80, since it is determined that the size cannot be copied to the main memory and the HDD web cache, the content is copied to the DVD-RAM web cache. Since there is no other place to copy, this copy processing is performed immediately instead of the write-back method.

In step 81, the process ends because there is no need to copy to the Web cache.

Step 82 is a jump destination of steps 71, 75, 79, and 80. In step 82, the Web cache management table 15 reflects the status of each Web cache that has been changed as a result of copying the Web cache up to that time.

This flow ends in step 83.

Next, the flow of the event 84 and steps 85 to 87 will be described. This flow is necessary when a write-back method is used for writing to the DVD-RAM.

This flow is activated when an event 84 occurs. Event 84 is generated by detecting the occurrence of a write request to the DVD-RAM at some trigger. The trigger may be, for example, a notification at a fixed interval by a timer, a notification that the total amount of information to be written exceeds a threshold value, an instruction from a user, or a command shown in FIG. This may be a write request generated in step 60 of the disc ejection flow, or an end signal issued immediately before the end of the web cache program.

In step 85, the landmarks of the entry to be backed up in the web cache management table 15 are checked, and all files corresponding to the entry with the D are checked. VD—Web cache area in RAM Copy to 20.

In step 86, the change in the Web cache on the DVD-RAM due to the copy processing performed in step 85 is reflected in the Web cache management table 15. Also, remove the mark for write-back of the copied entry.

This flow ends in step 87.

Next, the details of the Web cache management table 15 will be described with reference to FIGS.

First, the framework of the Web cache management table 15 will be described with reference to FIG. It is composed of the following six fields. Entry number field 101, URL field 102, file attribute attribute field 103, Main memory Web cache management field 16, a web cache management field 17 for the HDD, and a web cache management field 18 for the DVD-RAM. The entry number field 101 is a field for entering the serial number of an entry (line). The URL field 102 is a field for entering the URL of the entry. The file attribute field 103 is a field for storing a file attribute. In the present embodiment, the file size is focused on as the file attribute. The last three fields, 16, 17, and 18, are further subdivided into smaller fields, which are described with reference to FIGS.

The details of the web cache management field 16 in the main memory of the web cache management table 15 will be described with reference to FIG. The field 16 includes a file name field 104, an original creation date / time field 105, and a check date / time field 106. Web cache on main memory It is assumed that information is stored in the storage area 10 with a file name. Field 104 is a field that contains the file name. Field 105 is a field for entering the creation date and time of the original of the information to be stored. The original is information specified by a URL on the server device 23 on the network, and the date and time of creation is the date and time of creation of the original when the information was imported. In the field 106, the date and time when the creation date and time of the original on the server device 23 and the creation date and time of the field 105 are compared are entered.

The details of the Web cache management field 17 of the HDD in the Web cache management table 15 will be described with reference to FIG. The field 17 consists of a file name field 107, an original creation date and time field 108, a check date and time field 109, and a light knock flag field 110. . When storing information in the Web cache area 22 on the HDD, add a file name and store it. Field 107 is a field for entering the file name. Field 108 is a field for entering the date and time when the original was created. Field 109 is a field for entering the check date and time. Field 110 is required when copy processing to DVD-RAM is performed by the write-back method. Of the files in the Web cache area 22 on the HDD, mark the field 110 of the entry corresponding to the file that needs to be copied to the DVD-RAM. This is used in the flow described with reference to FIG.

The details of the web cache management field 18 of the DVD-RAM of the web cache management table 15 will be described with reference to FIG. The field 18 is composed of a file name field 111, an original creation date / time field 112, and a check date / time field 113. DVD-Web on RAM When storing information in the cache area 20, add the file name and store it. Field 1 1 1 is a field for entering the file name. Fields 1 1 and 2 are fields for entering the date and time when the original was created. Field 1 13 is a field for entering the check date and time.

Next, the details of the Web cache management table 21 on the HDD will be described with reference to FIG. It consists of the following four fields. Entry number field-1114, URL field '1 15', file attribute field 1 16, Web cache management field on HDD 1 1 7 Field 1 17 is further divided into three fields. The file name field is 118, the original creation date and time field is 119, and the check date and time field is 120. The web cache management table 21 on the HDD is stored in the web cache management field 17 of the HDD in the web cache management table 15 at the end of the web cache program 5. Created by extracting the tree.

Next, referring to FIG. 11, the details of the web cache management tape 19 on the DVD-RAM will be described in detail. The entry number field mainly consists of the following four fields. Field 1 2 1, 11! ¾ 1 ^ field 1 2 2, file attribute field 1 2 3, field for web cache management on HDD 1 2 4. Field 124 is further divided into three fields. The file name field is 125, the original date and time field is 126, and the check date and time field is 127. The Web Cache Management Table 19 on this DVD-RAM can be used in step 60 of the disc ejection flow shown in Fig. 4, at the end of the Web Cache Program 5, and in the write-back shown in Fig. 5. Written in step 86 of the processing flow. DVD to be written—W on RAM The eb cache management table 19 is created by extracting an entry in the web cache management field 18 of the DVD—RAM of the web cache management table 15.

Next, the pre-read list 14 will be described with reference to FIGS. It consists of the following five fields. The entry number field is 128, the URL field is 12, the storage destination field is 130, the storage file name field is 13, and the check date and time field is 1332. The addition of an entry to this pre-read list 14 is performed in step 50 of FIG. In the case of read-ahead processing according to the instruction of the browsing program 4, the obtained information on the server device 23 is stored in a Web cache, and its URL, storage destination, file name at the storage destination, and check are performed. The date and time are written to this pre-read list 14. The information obtained in the look-ahead processing is stored in main memory, HDD, or DVD-RAM, or in multiple ways by the cache management algorithm in Fig. 5. The storage destination indicates which of the storage destinations is stored.For example, when the storage is performed in both the main memory and the HDD, the storage is performed using the priority of the storage destination described above. It is assumed that the destination is the main memory. The storage destination file name is the file name at the storage destination. The check date and time is the time when the information was obtained. If the URL specified by the user is in the pre-read list 14, it is determined as a hit in step 41 of FIG. Even without searching the Web cache management table 15, it is possible to obtain the optimum storage location where the copy is stored and its file name. The check date and time are used in steps 45 of FIG.

Next, referring to FIG. 13, the browsing program 4 displays the browsing window 201 displayed on the screen of the monitor device 35 and how the browsing program 4 works. Explain whether to issue a prefetch request. The browsing window 201 has a symbol mark 202, a menu bar 203, a URL input field 204, and a scroll bar 205. The user enters the URL of the information to be viewed in the URL input field 204. The menu bar 203 has a plurality of menus, which can be used to issue commands to the browsing program 4. The display can be scrolled by using the scroll bar 205 to browse parts that cannot be displayed at once. The area 206 surrounded by the dotted line is the area that could not be displayed (in other words, the area displayed after scrolling). Such an area can be displayed using a scroll bar 205. When the user inputs the URL of the information to be viewed in the URL input field 204, an event 39 in FIG. 4 occurs. If the desired information is in the web cache, the information is fetched from the web cache from the server device 23 when there is no information or when the original is newer. When information is imported, the display color of the symbol mark 202 is changed or a simple animation is displayed to indicate that information is being imported.

In FIG. 13, character information is displayed in the display window. Of these, the parts 207, 209, 209, 210, 211, which are shown with an underline, are called anchors. An anchor is a part linked to other information, and the association is specified by a URL. When the user points to the anchor, the effect is the same as that of inputting the URL specifying the association in the URL input field 204, and the information of the URL is taken in and displayed. In this way, the association of information by the anchor is called a hyperlink, and switching of the browse information by specifying the anchor is called a jump. As a way of browsing information, U to the URL input field 204 There is a tendency for hyperlink jumps to be used more frequently than for RL direct input.

Taking the display screen of FIG. 13 as an example, a method of issuing a prefetch request by the browsing program 4 will be described. In the display screen of FIG. 13, anchors 207, 208, and 209 are currently displayed. Anchors 2 0 and 2 1 1 are in hidden areas that cannot be displayed unless scrolled. In this case, it is predicted that the next instruction by the user is likely to be one of the displayed anchors 207, 209, and 209. Then, for example, priorities are assigned in order from the top of the display, and the priority is determined to be higher in the order of anchor 210, 208, and 209. Even if there is no instruction from the user, a prefetch request is issued by specifying the anchors in order from the highest priority. The prefetch request is performed by specifying the URL of the hyperlink destination of the target anchor, which results in event 40 shown in FIG. The information of the hyperlink destination is taken into the Web cache from the server device 23 on the network by the prefetching process. If the user later designates the anchor to be prefetched, the information fetching process can be omitted, and the delay time from the designation to the start of browsing can be shortened.

If the display attribute of the target anchor is changed during the prefetching process, and the display attribute of the anchor for which the prefetching process is completed is also changed, the operation of the user will be a hint. It is also common to change the display attributes of anchors that have already been viewed. For example, an unviewed anchor is displayed in blue, an anchor that has been viewed is purple, an anchor that is being prefetched is displayed in orange, and an anchor that has been prefetched is displayed in green.

Next, three-dimensional graphics are displayed in the browsing window 201 according to Fig. 14. The state of issuing a prefetch request will be described using the example shown. Depending on the information being viewed, 3D graphics may be displayed, as described here. In some cases, it may be possible to browse through the three-dimensional graphics as if by a user's instruction. In this example, a picture of the corridor is displayed in the three-dimensional graphics display area 2 12. Door A 2 13 is displayed on the left side of the corridor wall, and door B 2 14 is displayed on the right side. It is assumed that these doors are hyperlinked so that when the door is pointed, the user can jump to the URL associated with the door. In fact, when you turn left at the end of this corridor, it is assumed that there is a door C at the end of the corridor (not shown). In such a scene setting, the target of the prefetch request is the door A213 and the door B214. Since door A is closer to the user's viewpoint, it is assumed that the priority is higher. In this way, even when information is displayed in the form of three-dimensional graphics and a hyperlink is embedded therein, the read-ahead processing request is issued in order with the read-ahead priority.

In FIGS. 13 and 14, a case will be described in which the user explicitly specifies an anchor or a portion in which a hyperlink is embedded during the prefetching process. If the hyperlink specified by the user is in the process of prefetching, the process is continued, and it is determined that the prefetching process is not performed in the condition judgment in step 48 in FIG. If the hyperlink specified by the user is not the one currently being prefetched, the prefetching is interrupted. If interrupted, the information that was being stored in the Web cache is discarded.

The disc ejection process for taking out the disc 37 from the DVD-RAM drive 33 will be described with reference to FIGS. 15, 16, 17, and 18. As described in Figs. 4 and 5, when the disc 37 is ejected, Write processing is required. When the user presses the eject button on the DVD-RAM drive 33, it is necessary to control the writing process to complete before ejecting the disc.

The ejection process of the disc 37 will be described with reference to FIG. The DVD-RAM drive 33 has a disc 37 mounted thereon and includes an eject button 302 that can be operated by a user, a disc ejection request signal generating circuit 303, and a disc ejection mechanism 304. The disc ejection mechanism 304 is a mechanical mechanism for removing the disc 37 mounted on the user so that the user can take out the disc 37 from the DV-RAM drive 33. FIG. 15 also shows a disc ejection processing routine 301. This is described in FIG. 4 and is a part of the Web cache program 5.

When the user operates the eject button 302, the disc ejection request signal generating circuit 303 operates, and a disc ejection request signal is issued to the Web cache program 5. When the Web cache program 5 detects this signal, an event 58 is generated and the disk discharge processing routine 301 is started. In step 59, the necessary entries are extracted from the Web cache management table 15 to create a table to be written to the disk 37. In step 60, the created table, the file to be copied from the Web cache area 22 on the HDD for the write-back method, and the current time are written to the disk 37. When all the writing processes are completed, a disc ejection instruction signal is issued in step 61, and the flow ends in step 62. The disc ejection instruction signal issued in step 61 is given to the disc ejection mechanism 304, and the disc 37 is ejected.

If the system goes into an abnormal state, disc 37 is forcibly ejected. It is better to have a means to make it happen. Although not shown, a switch may be provided for the purpose of directly giving the _discharge request signal to the disc discharge mechanism. It is desirable that this switch should not be easily pressed with a fingertip. It may be difficult to remove it with a cover or to operate it only at the end of a pin.

FIG. 16 is a time chart of an important part of the processing described in FIG. The disc ejection processing time chart 305 includes a time chart 306 for the disc ejection request signal, a time chart 308 for the disc ejection instruction signal, and a time chart for the operation period of the disc ejection processing routine. 3 1 0 is illustrated. The part indicated by reference numeral 307 indicates the assertion period of the disc ejection request signal. The assertion period is the period during which the signal level corresponding to logical value 1 is output. The portion indicated by reference numeral 309 indicates an assertion period of the disc ejection instruction signal. The part indicated by reference numeral 311 is the operation period of the disc ejection processing routine.

It is assumed that the eject button 302 is operated and a disc ejection request signal is issued from the disc ejection request signal generation circuit 303 at the timing of reference numeral 307. In response, the disc ejection processing routine operates for the period indicated by reference numeral 311. A disc ejection instruction signal is issued at the timing indicated by reference numeral 309, and the disc ejection mechanism 304 operates.

Another method of realizing the ejection process of the disk 37 will be described with reference to FIG. DVD—Disk 3 7 is mounted on RAM drive 3 3. The DVD—RAM drive 33 includes an eject button 302, a disc ejection request signal generation circuit 314, a disc ejection suppression circuit 315, and a disc ejection mechanism 316. The path indicated by reference numeral 3 17 is the path of the discharge request reset signal. De The disk discharge suppression circuit 315 is functionally a switch, and passes the disk discharge request signal from the disk discharge request signal generation circuit 314 to the disk discharge mechanism 316, Or not pass. The disk discharge suppression circuit 315 is normally open during the operation of the web cache program, and does not pass the disk discharge request signal from the disk discharge request signal generation circuit 314. . The disc ejection mechanism 316 is a mechanical mechanism that ejects a disc in the same way as the disc ejection mechanism 304 in Fig. 15, and additionally generates a disc ejection request signal when ejecting a disc. Issue to circuit 3 1 4. FIG. 17 also shows a disk ejection processing routine 3 1 2. This is almost the same as the disc ejection processing routine 301 described in FIG. The difference is that step 61 of the disc ejection processing routine 301 is step 313, and that the signal issued is not a disc ejection instruction but a disc ejection permission.

When the user operates the eject button 302, the disc ejection request signal generation circuit 314 operates, and the disc ejection request signal passes through the disc ejection suppression circuit 315 and the disc ejection mechanism 316. Output to The disc ejection suppression circuit 315 is open during the operation of the web cache program 5, and the outputted disc ejection request signal does not reach the disc ejection mechanism 316. On the other hand, when the Web cache program 5 detects the generation of the disc ejection request signal, an event 58 is generated and the disc ejection processing routine 312 is started. In step 59, the necessary entries are extracted from the web cache management table 15 to create a table to be written to the disk 37. In step 60, the created table and files to be copied from the web cache area 22 on the HDD for the write-back method, And the current time to disk 37. When all writing processes have been completed, a disc ejection permission signal is issued in step 3 13, and the flow ends in step 62. The disc ejection permission signal issued in step 3 13 is given to the disc ejection suppression circuit 3 15, and the circuit is closed. As a result, the disc ejection request signal from the disc ejection request signal generating circuit 314 passes through and is given to the disc ejection mechanism 316. In response to this, the disk discharge mechanism 316 operates. At this time, the ejection request reset signal is given to the disc ejection request signal generation circuit 314 as shown by reference numeral 317, and the disc ejection request signal is reset.

FIG. 18 is a time chart of an important part of the processing described in FIG. The disc ejection processing time chart 318 includes a time chart 319 of the status of the disc ejection suppression circuit, a timing chart 320 during a web cache program operation period, and a disc ejection request signal. Time chart 3 2 2, time chart 3 2 4 of the disc ejection permission signal, time chart 3 2 6 of the ejection instruction to the disc ejection mechanism, time chart 3 2 8 of the ejection request reset signal, A time chart 330 of the operation period of the disc ejection processing routine is shown. The part indicated by reference numeral 3 21 indicates the Web cache program operation period. The portion indicated by the reference numeral 323 indicates the assertion period of the disc ejection request signal. The portion indicated by the reference numeral 325 indicates the assertion period of the disc ejection permission signal. At a portion indicated by reference numeral 327, an ejection instruction is given to the disc ejection mechanism. The portion indicated by reference numeral 329 is an assertion period of the discharge request reset signal. The portion indicated by reference numeral 331 is the operation period of the disc ejection processing routine. It is assumed that the Web cache program 5 operates during the period indicated by reference numeral 3 2 1. During this period, the disc discharge suppression circuit 3 15 is denoted by reference numeral 3 19. As a result, the disk ejection request signal generation circuit 314 suppresses the transmission of the disc ejection signal. When the user operates the eject button 302, the disc ejection request signal generation circuit operates, and the disc ejection request signal is output during the period indicated by reference numeral 323. When this is detected by the Web cache program 5, the disk ejection processing routine 312 is operated for a period indicated by reference numeral 331. In step 313 of the above, a disc ejection permission signal is issued at the timing indicated by reference numeral 325. This is given to the disc ejection suppression circuit 315, and the state is closed only while the disc ejection permission signal is asserted. As a result, the disc ejection request signal passes through the disc ejection suppression circuit 315 and is output as a discard instruction to the disc ejection mechanism for a period indicated by reference numeral 327. In response to this, the disc ejection mechanism 3 16 operates to eject the disc. At the same time, an emission request reset signal is output at the timing indicated by reference numeral 329. In response to the ejection request reset signal, the disc ejection request signal is canceled, and the period indicated by reference numeral 323 ends.

The embodiment of the present invention has been described with reference to FIGS. 1 to 18. In the browsing apparatus of this embodiment, the Web cache is also configured as a DVD-RAM disc. If the user carries this DVD-RAM disk, even when using another browsing device, information that the user has recently viewed or frequently browses is stored in the Web cache of the DVD-RAM disk. Therefore, it can be browsed immediately without network access. This means that, for example, a user who normally performs browsing work using a browsing device connected to a high-speed LAN can use a browsing device temporarily connected via a telephone line.

Producing browsing work for recently viewed or frequently viewed information The effect is that the sex can be maintained. Specifically, there may be cases where a salesman who browses a sales catalog at an office goes to a customer and shows the sales catalog to the customer. In addition, if you obtain a disk containing information provided on the network in the form of a web cache in advance, this information will be added to the web cache and indicate the URL. In this case, it is possible to browse without changing the browsing method at all, and since the main information to be browsed is not ordered from the network at that time, comfortable browsing can be performed even if the network environment is poor. This has the effect.

Further, in this embodiment, before a user's instruction, information of a hyperlink destination that is likely to be browsed is prefetched into the Web cache. This means that while the user is browsing the current display screen, the user starts acquiring information on the hyperlink destination that is likely to be viewed next. As a result, it is possible to increase the possibility that the information of the hyperlink destination specified by the user is stored in the Web cache. As a result, it is possible to reduce the average value of the delay time from the user's instruction to the display of information.

In this embodiment, a Web cache is configured on a DVD-RAM disk. However, in order to maintain the consistency of the contents, a write process to the DVD-RAM disk is required when the disk is ejected. According to this embodiment, even if the user attempts to eject a disc using the eject button of the DVD-RAM drive, the disc can be prevented from being ejected until the necessary writing process is completed. . Therefore, it is possible to prevent the disc contents from being destroyed due to the incomplete completion of the final writing process.

As can be seen from the above description, the Web By constructing a web cache, users can carry web caches according to their browsing history. If the user browses the information once and the original data has not been updated since then, it is possible to hide the delay time for obtaining the information even if another browsing device is used. Even if the browsing device to which the user travels while carrying the Web cache is connected to the network via a low-speed line such as a telephone line, or is not connected to the network, the storage medium can be used. The information in the web cache inside can be viewed immediately.

In addition, if the information provided by the information provider on the network is stored in a storage medium in the form of a Web cache and passed to the viewer, the viewer does not need to obtain the information via the network. It becomes possible to browse.

By pre-reading the information of the hyperlink destination of the anchor displayed on the browsing screen or a similar display object and storing it in the Web cache, the delay time of obtaining the information at the time of hyperlink is reduced. You can hide it. Also, by setting the display attribute of the anchor for which the pre-reading of the hyperlink destination information has been completed and the display attribute of the pre-reading anchor to be different from that of other texts or anchors, the user can be notified of the progress of the pre-reading. Can be done.

When a user attempts to remove a removable storage medium with a web cache by using the eject button, the system must execute the necessary processing in the program, and then execute an ejection command or By issuing the discharge permission, it is possible to prevent the storage medium from being taken out without completing the write processing for the Web cache.

At the time of removing the storage medium, the current time (including the date) and the time difference between the time and a specific time zone, for example, Greenwich Mean Time, are stored in the storage medium. By writing on the body, it is possible to simplify the processing related to the check date and time of the web cache and to correct the time difference between the check date and time.

Also, a portion in which a program to be executed by the terminal device is recorded on a recording medium (DVD-RAM) that can be freely attached to and detached from the terminal device (viewing device), and the program is connected to the terminal device By providing a portion for recording the information from the network as cache data, the environment for accessing the Internet as shown in the present embodiment (the program that executes this process itself) And a storage area used as a cache) can be provided by the single recording medium. In other words, by carrying the recording medium to another computer and executing the program on the other computer, the network access environment described in the present invention can be realized on another computer. .

Specifically, the browsing program shown in the embodiment is stored in a portion where the program is recorded. The part where the information from the network is recorded as cache data is the Web cache area shown in the embodiment. A Web cache management table area is also provided on DVD-RAM.

Industrial applicability

As described above, the browsing device according to the present invention can be used as a browsing device receiving a World Wide Web (WWW) service or a client 'system such as a personal computer. Displaying a copy at the next and subsequent accesses is useful for shortening the time until display and improving the user interface. Further, the recording medium according to the present invention supplies the above functions to the above-mentioned browsing device and client system in the form of software, and also provides a cache for reducing the load on the network. It is useful as an offer.

Claims

The scope of the claims

1. A terminal device characterized in that a storage medium for storing information from a network as cache data can be freely attached and detached.

2. The terminal device according to claim 1, wherein the terminal device has means for recording the information as cache data in a secondary storage device other than the storage medium.

3. The terminal device according to claim 1, wherein said storage medium is DVD-RAM.

4. The terminal device according to claim 2, wherein said storage medium is DVD-RAM.

5. The terminal device according to claim 4, wherein the secondary storage device is a hard disk.

6. The scope of claim 1, wherein said terminal device has means for recording said information as cache data in a secondary storage device other than said storage medium and also in a main memory. The terminal device as described in the above.

7. The terminal device according to claim 6, wherein said storage medium is DVD-RAM.

8. The terminal device according to claim 7, wherein the secondary storage device is a hard disk.

9. A browsing device characterized in that a storage medium for storing information from a network as cache data can be freely attached and detached.

10. The terminal device according to claim 9, wherein the terminal device has means for recording the information as cache data in a secondary storage device other than the storage medium. The reading device described in the section.

11. The browsing device according to claim 9, wherein the storage medium is DVD-RAM.

1 2. An information access method from a terminal device used by being connected to a network,

Writing a copy of information from the network to a storage medium that can be freely attached to and detached from the terminal device;

When the terminal accesses the information, first, a step of accessing the storage medium;

Obtaining the information via the network when the information is not present in the storage medium.

13. A terminal device connected to a network for accessing information, comprising a storage medium that can be freely attached to and detached from the terminal device;

A terminal device having means for storing information from the network as cache data in the recording medium.

14. A recording medium that can be freely attached to and detached from the terminal device.

The recording medium has a portion in which a program to be executed by the terminal device is recorded, and a portion in which the program records, as cache data, information from the network to which the terminal device is connected. A recording medium characterized by the following.

15. The recording medium according to claim 14, wherein said recording medium is DVD-RAM.

16. A recording medium that can be freely attached to and detached from the terminal device.

The recording medium stores information from the network to which the terminal device is connected. A recording medium characterized by having a portion for recording a program for recording as cache data on a recording medium that can be freely attached to and detached from the terminal device.

17. The recording medium according to claim 16, wherein said recording medium is DVD-RAM.

18. A method for obtaining information from a terminal device that obtains information from a network.

Prioritizing the anchors displayed on the display screen of the terminal device;

An information obtaining method comprising a step of obtaining, via a network, link destination information indicated by an anchor according to the priority order before a user designates an anchor.

19. A terminal device having the method according to claim 18.

20. A recording medium on which a program for executing the method according to claim 18 is recorded.

2 1. In the information obtaining method described in claim 18,

An information acquisition step having a step of mutually changing a display attribute of an anchor which has begun obtaining information before the user designates an anchor, a display attribute of an anchor which has been obtained, and a display attribute of an anchor which has not been obtained. How to approach.

22. A terminal device having the method according to claim 21.

23. A recording medium on which a program for executing the method according to claim 21 is recorded.

2 4. Accessing information from a terminal that obtains information from the network Law,

Before the user designates the anchor, obtaining the link destination information indicated by the anchor according to the priority order via the network; and storing the information in a storage medium that can be freely attached to and detached from the terminal device. Recording the information from the network as cache data.

25. A terminal device having the method according to claim 24.

26. A recording medium storing a program for executing the method according to claim 24.

27. A storage medium for storing information from the network as cache data is made freely attachable and detachable, and the cache data is recorded on the recording medium as cache data that can be used in other terminal devices. A terminal device characterized in that:

28. The terminal according to claim 27, wherein said terminal device has means for recording said information as cache data in a secondary storage device other than said storage medium. apparatus.

29. The terminal device according to claim 27, wherein said storage medium is DVD-RAM.

30. The terminal device according to claim 27, wherein said storage medium is DVD-RAM.

31. The terminal device according to claim 30, wherein said secondary storage device is a hard disk.

32. The terminal device according to claim 27, wherein the terminal device has means for recording the information as cache data in a secondary storage device other than the storage medium and also in the main memory. Terminal device.

33. The terminal device according to claim 32, wherein the storage medium is a DVD-RAM.

34. The terminal device according to claim 33, wherein said secondary storage device is a hard disk.

35. A cache storage device that uses a storage device that records information on a removable storage medium as cache storage, and holds the cache storage in the storage medium.

36. A storage device for recording information on a removable storage medium is used as a cache storage for storing a copy of information obtained via a network, and the cache storage is stored in the storage medium. Cache storage device that holds the

37. A combination of a storage device that records information on a removable storage medium and another secondary storage device is used as a cache storage for storing a copy of information obtained via a network, and the storage device is used as a cache storage device. A cache storage control method for storing the cache storage in a medium.

38. A medium storing a cache control program incorporating the cache storage method according to claim 37.

39. A cache storage device controlled by the cache storage control method according to claim 37.

40. A browsing device comprising the cache storage device according to claim 39.

41. The cache storage device according to claim 39, wherein the storage device for recording information on the removable storage medium is a DVD-RAM drive. A cache storage device using a hard disk drive as the secondary storage device.

42. A browsing device provided with the cache storage device according to claim 41.

4 3. Combining a main memory with a storage device that records information on a removable storage medium and other secondary storage devices, and using it as a cache memory to store a copy of information obtained via a network And a cache storage device for holding the cache storage in the storage medium.

44. A browsing device provided with the cache storage device according to claim 43.

45. The cache storage device according to claim 43, wherein a DVD-RAM drive is used as a storage device for recording information on the removable storage medium, A cache storage device that uses a hard disk drive as the storage device.

46. A browsing device provided with the cache storage device according to claim 45.

47. A first directory table for associating the address of the information on the network with the address of the information stored on the storage medium as cache data on the storage medium. Is provided in the storage medium,

A second directory for associating an address on the network of the information with an address on the secondary storage device of the information stored as cache data in the secondary storage device. Providing a trie table in the secondary storage device;

The first directory table and the second directory table are created by merging the information with the network address of the information as a key, and are created on the storage medium. Means for searching cache data using a third directory table including a field for a dress and a field for an address on the secondary storage device; The end according to claim 2 characterized by the following: Equipment,

48. The terminal device according to claim 47, further comprising means for checking whether or not said first directory table exists in said storage medium when said storage medium is mounted. .

49. When installing the storage medium, check whether the first directory table exists in the storage medium, and if so, key the address of the information on the network. 49. The terminal device according to claim 48, further comprising: means for merging said first directory table with said third directory table.

50. At the time of taking out the storage medium I In the third directory table, the address where the address on the storage medium of the information stored as cache data in the storage medium is entered. Extracting the entry, updating the first directory table with the information of the extracted entry, and reading the extracted entry for an address on the storage medium. The terminal device according to claim 47, further comprising means for clearing a field.

51. A first directory table for associating the address of the information on the network with the address of the information stored on the storage medium as cache data on the storage medium. Is provided in the storage medium,

A second directory for associating an address on the network of the information with an address on the secondary storage device of the information stored as cache data in the secondary storage device. Providing a tri-table in the secondary storage device;

The first directory table and the second directory table are created by merging the information with the network address of the information as a key, and are created on the storage medium. Field for the dress and the address for the address on the secondary storage device 29. The terminal device according to claim 28, further comprising means for searching for cache data using a third directory table having a field.

52. The terminal according to claim 51, further comprising means for checking whether or not said first directory table exists in said storage medium when said storage medium is mounted. apparatus.

5 3. When the storage medium is mounted, it is checked whether or not the first directory table exists in the storage medium, and if so, the address of the information on the network is determined. The terminal device according to claim 52, further comprising: means for merging the first directory table with the third directory table as a key.

54. At the time of removal of the storage medium, an entry in which the address of the information stored as cache data on the storage medium is written in the third directory table, on the storage medium. And updates the first directory table with the information of the extracted entry, and saves the field for the address of the extracted entry on the storage medium. The terminal device according to claim 51, characterized by having a means for clearing.

5 5. A method for accessing information from a terminal device connected to a network and used.

From a storage medium in which a copy of information from a network is written as data to a storage medium that can be freely attached to and detached from the terminal device, a first directory relating to data on the storage medium Referencing a resettable;

A copy of the information from the network is copied to the secondary storage device in the terminal device. Referring to a second directory table for data of the secondary storage device in the terminal device to be written as data, and referring to the first directory table. And accessing the storage medium or the secondary storage device by using the results of both the step of performing the operation and the step of referring to the second directory table.

If both results indicate that the information is absent in both the storage medium and the secondary storage device, the method may include a step of obtaining the information via the network. An information access method characterized by the following.

56. The information access method according to claim 55, wherein a step of referring to said first directory table is executed when said storage medium is mounted on said terminal device.

57. A claim as claimed in claim 55, characterized in that when the information is obtained via a network, a step of recording the information in one of the storage medium and the secondary storage device is provided. Information access method described.

58. The recording medium according to claim 14, wherein the recording medium has a portion in which directory data relating to the cache data is recorded and which is accessed by the program. recoding media.

59. The recording medium according to claim 58, wherein said recording medium is DVD-RAM.

60. In a storage device that records information on a removable storage medium, when a user issues an instruction to eject the storage medium to the storage device, the storage device and the system in which the storage device is connected are connected. If there is information to be recorded on the storage medium, the writing process is performed on the storage medium. After the writing process is completed, the system issues a command to eject the storage medium to the storage device. Control method that gives an order.

61. A medium storing the control method according to claim 60.

62. A system comprising a storage device for recording information on a removable storage medium, wherein the system is controlled by the control method according to claim 60.

63. The control method according to claim 60, wherein at the time of said writing processing, information relating to date and time is recorded in said storage medium.

64. The control method according to claim 60, wherein during the writing process, information on a date and time and information on a time difference between the time and a specific time zone are recorded in the storage medium.

65. In a storage device that records information on a removable storage medium, when a user issues an instruction to eject the storage medium to the storage device, the storage device and the system to which the storage device is connected are connected. If there is information to be recorded on the storage medium, the writing process is performed on the storage medium, and after the writing process is completed, the system issues a permission to eject the storage medium to the storage device. Give control method.

66. A medium storing the control method according to claim 65.

67. A system provided with a storage device for recording information on a removable storage medium, wherein the system is controlled by the control method according to claim 65.

68. The control method according to claim 65, wherein at the time of said writing processing, information relating to date and time is recorded in said storage medium.

6 9. The method according to claim 6, wherein, in the writing process, information on a date and a time and information on a time difference between the time and a specific time zone are recorded on the storage medium. The control method described in item 5.

70. A combination of a storage device that records information on a removable storage medium and another secondary storage device is used as a cache storage for storing a copy of information obtained via a network, and the storage device is used as a storage device. In a system for controlling the cache storage by a method of retaining the cache storage also in a medium, when a user issues a storage medium ejection instruction to the storage device, the storage medium is stored in the cache storage. If there is information to be recorded in the storage medium, a write process for the storage medium is performed, and after the write process is completed, the system issues a storage medium ejection command to the storage device.

71. A cache storage device controlled by the control method according to claim 70.

72. A browsing device controlled by the control method according to claim 70.

73. The control method according to claim 70, wherein at the time of said writing processing, information relating to a date and a time is recorded in said storage medium.

74. The control method according to claim 70, wherein at the time of said writing process, information relating to a date and time and information relating to a time difference between said time and a specific time zone are recorded in said storage medium.

75. A cache storage device controlled by the control method according to claim 74.

76. A browsing device controlled by the control method according to claim 74.

7 7. A combination of a storage device that records information on a removable storage medium and another secondary storage device is used as a cache storage for storing a copy of information acquired via a network, and the storage device is used as a cache storage device. In a system for controlling a cache memory by a method of retaining the cache memory even in a medium, When the storage medium is instructed to eject the storage medium, when there is information to be recorded on the storage medium in the cache storage, a write process is performed on the storage medium, and the write process is completed. And a control method for permitting the storage device to eject the storage medium from the system.

78. A cache storage device controlled by the control method according to claim 77.

79. A browsing device controlled by the control method according to claim 77.

80. The control method according to claim 77, wherein at the time of said writing processing, information relating to a date and a time is recorded in said storage medium.

81. The control method according to claim 77, wherein at the time of the writing process, information relating to a date and time and information relating to a time difference between the time and a specific time zone are recorded in the storage medium.

82. A cache memory device controlled by the control method according to claim 81.

83. A browsing device controlled by the control method according to claim 81.