JP2002033787A - Client/sever type information synchronizing control method and information synchronizing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for speedily reflecting each of terminals with updated information, at synchronizing of information updating, while suppressing the load of terminals on a network when constructing an information synchronizing system, while utilizing a request-response type communication protocol in an internet environment in a client/server type system. SOLUTION: When a synchronizing information acquisition request from a client is received in a synchronizing information managing processing to be executed in a server, synchronizing information specified by that request is compared with synchronizing information managed in the server. When both the information is equal, a response to a client is held for a elapse of a fixed time or until the synchronizing information managed in the server is updated. After the elapse of fixed time or when the synchronizing information managed in the server is updated, the synchronizing information managed in the server is immediately returned to the client as a response.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a client-server type information synchronization control method and an information synchronization system, in which information is managed by a server, and each client references and updates the information. And especially
As a communication protocol between client and server,
A client that is suitable for use when updating and referencing a Web page document on a Web server using an HTTP (Hyper Text Transfer Protocol) protocol, and that promptly notifies and reflects updated synchronization information to each client. Server-type information synchronization control method,
And an information synchronization system.

[0002]

2. Description of the Related Art Conventionally, automatic updating of a Web page is performed by a push-type software of a “request-response method” in which a client periodically obtains information from a server, or by an information distribution side upon a content update. This has been done using push-type software of the "event-driven system" for simultaneous distribution. The former may be classified as “pseudo push type” and the latter may be classified as “real push type”. The pseudo push type has been used on the Internet, and the real push type has been used on the intranet. There is an article about push-type software in Nikkei Communication 1997.7.7, pp.126-129.

In order to reduce traffic when using the push technology, a DRP (Distribution a
nd Replication Protocol). The DRP reduces the traffic by checking the changed portion of the homepage or software to be transmitted / received using a checksum and exchanging only the updated portion.

[0004] With regard to the Internet technology called push or channel, for example, US Pat.
In addition, regarding automatic distribution of update files, for example, US
6029175.

[0005]

As a mechanism for automatically reflecting the update of the synchronization information centrally managed by the server to the client, a real push type information distribution method is suitable. Is suitable for use on an intranet such as a LAN (Local Area Network), but not suitable for use on the Internet. Broadcasting to all devices connected to the Internet
This is not a realistic story.

On the other hand, when the update reflection speed is increased by the pseudo-push type push method, the information acquisition interval from the client may be narrowed. However, if the frequency of information acquisition requests and responses increases, the server load and the network increase. The load also increases. Techniques such as DRP are effective in reflecting when a document or a part of a file is updated, but are not effective in a case where the entire information managed in synchronization is updated at the time of updating.

In order to quickly update the information of the server and the client, it is only necessary to keep the communication link between the client and the server.
In particular, the HTTP protocol often used in the Internet environment is a communication protocol in which a connection is disconnected every time a response to a request is completed.
It is not a protocol that maintains a communication link between the client and the server.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to construct an information synchronization system using a request-response communication protocol in an Internet environment in a client-server system. In this case, it is an object of the present invention to provide a mechanism for promptly reflecting the update information at the time of updating the synchronization information to each terminal while suppressing the load on the network and the terminal.

[0009]

In order to achieve the above object, according to the present invention, there is provided a client-server type information synchronization control method, wherein synchronization information is centrally managed by a server.
In a client-server type information synchronization control method in which a client refers to and updates the synchronization information, a synchronization information that specifies synchronization information currently held by the client and periodically inquires the server of the latest synchronization information. An acquisition request process, a synchronization information update process of updating the synchronization information managed by the server from the client, and a synchronization information management process executed by the server. The synchronization information management process is performed by the client. When the synchronization information acquisition request is received from the server, the synchronization information specified in the request is compared with the synchronization information managed by the server. The managed synchronization information is returned to the client as a response. On the other hand, if both are the same, a certain time elapses. Or the response to the client is held until the synchronization information managed by the server is updated, and immediately after the fixed time elapses or the synchronization information managed by the server is updated. And a process of returning synchronization information managed by the server to the client as a response.

More specifically, in the above-mentioned client-server type information synchronization control method, an HTTP (Hype) is used as a communication protocol between the client and the server.
r Text Transfer Protocol).

In order to achieve the above object, a configuration of the invention relating to a client-server type information synchronization system of the present invention is a client-server in which synchronization information is centrally managed by a server and a client references and updates the synchronization information. In this type of information synchronization system, this system specifies synchronization information currently held by the client, and periodically requests the server for the latest synchronization information. Synchronization information updating means for updating the synchronization information from the client, and synchronization information management means executed by the server, wherein the synchronization information management means receives a synchronization information acquisition request from the client. Comparing the synchronization information specified in the request with the synchronization information managed by the server If the two are different, the synchronization information managed by the server is immediately returned to the client as a response. On the other hand, if the two are the same, a certain time elapses or the server manages the synchronization information. The response to the client is held until the synchronization information being updated is updated, and after a predetermined time has elapsed or the synchronization information managed by the server has been updated, the response is immediately managed by the server. A process for returning the synchronization information to the client as a response is performed.

More specifically, in the client-server type information synchronization system, HTTP is used as a communication protocol between the client and the server.

More specifically, in the client-server type information synchronizing system, the information to be synchronized is information of an electronic dialogue performed on the basis of a browser.

More specifically, in the client-server type information synchronizing system, the synchronizing information managed centrally by the server is an address indicating the location of a document to be synchronously referred to.

More specifically, in the client-server type information synchronization system, the synchronization information centrally managed by the server is coordinate values of a cursor indicating a position inside a document which can be displayed by the client. Things.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment according to the present invention will be described below with reference to FIGS. First, a state transition model for referring to and updating a document when the document is managed by a client-server system will be described with reference to FIG. The following embodiments will be described on the premise of this state transition. FIG. 1 is a schematic diagram of a state transition when a document is referenced and updated in a client-server system.

State 1 is an initial state or a state before an event occurs.

As a state before the occurrence of the event, for example, a state in which the browser 5 of the terminal 1 and the browser 6 of the terminal 2 refer to the same document (A) is shown. If the referenced document is WWW (World Wide Web) content (usually an HTML (HyperText Markup Language) document), the document is distributed from the WWW server 3, but the referenced document is managed by a file server or the like. It can be a document to be created.

In the state 2, the document referred to by the terminal 2 is changed to B, and the document referred to in synchronization with the terminal
The state in which an instruction is sent from the terminal 2 to the WWW server 3 so as to change to "1" is shown.

State 3 shows a state in which the display content of the synchronization reference screen (browser) 5 displayed on the terminal 1 has been updated to B. The content to be synchronously referenced is centrally managed by the WWW server 3, and the terminal 1 (similarly to the terminal 2) periodically inquires the WWW server 3 of the content to be synchronously referenced.

Next, the configuration of the client terminal will be described with reference to FIG. FIG. 2 is a functional configuration diagram of the client terminal according to the present embodiment.

The client terminal 10 is a computer having a general configuration including a CPU, a main storage device, and various input / output devices in terms of hardware, and has a network interface 19 for connecting to a LAN or the Internet. ing.

On the other hand, functionally, a display control module 15 and a synchronization monitoring module 16 are added to a browser 13 operating on the OS 12. As long as a general browser function is realized, the OS 12 and the browser 13 may be integrated.

Important for implementing the present invention are a display control module 15 and a synchronization monitoring module 16.
The synchronization monitoring module 16 is a module that communicates information synchronously with the WWW server side.
Reference numeral 5 denotes a module that cooperates with the synchronization monitoring module 16 to maintain display consistency.

The display control module 15 and the synchronization monitoring module 16
0, or may be downloaded from a network, for example, from the WWW server 3 and dynamically executed when used.

Next, the configuration of the WWW server 3 will be described with reference to FIG. FIG. 3 shows a WWW server 3 according to the present embodiment.
FIG. 2 is a functional configuration diagram.

The hardware is a computer having a general configuration including a CPU, a main storage device, and various input / output devices. However, in general, the performance and performance of the computer are lower than those of a computer used in a client terminal. Excellent in terms of reliability.

Also, having a network interface 29 for connecting to a LAN or the Internet is the same as a client terminal.

On the other hand, functionally, a WWW server function 23 operating on the OS 22 has a synchronization information management module 24
Is added. As long as a general WWW server function is realized, the OS 22 and the WWW server 23 may be integrated.

The synchronization information management module 24 is a module that manages each interactive session and is the center of information synchronization.

The synchronization information management module 24 has a session management table 25 for managing each session for synchronously referring to a document.

The session management table 25 stores a session ID 26 which is an identifier of a session and an address (URL: Uniform Resource L
ocator) 27 and the address 28 of the terminal participating in the session.

In the case where the management is performed using the session ID 26 as a key, the items required for the synchronization control of the present invention are the session ID 26 and the address 27 of the document.
Therefore, the terminal address 28 may not be provided. This is because if the synchronous communication between the client terminal 10 and the WWW server 3 is based on the HTTP protocol, the WWW server 3 only returns a response to the request, so that it is not necessary to particularly keep the terminal participating in the session.

However, if the terminal address 28 is held, there are advantages in management such as a communication log can be taken and a message can be sent from the WWW server 3.

Next, the structure of messages and packets exchanged in the client-server type information synchronization system of the present invention will be described with reference to FIGS. FIG.
From the display control module 15 to the synchronization monitoring module 1
FIG. 6 is a configuration diagram of message contents issued to the client 6;
FIG. 5 is a configuration diagram of the message content issued from the synchronization monitoring module 16 to the display control module 15. FIG. 6 is a configuration diagram of a packet sent from the synchronization monitoring module 16 to the synchronization information management module 24. FIG.
FIG. 3 is a configuration diagram of a packet sent from the synchronization information management module 24 to the synchronization monitoring module 16. FIG. 8 shows the synchronization monitoring module 16 to the synchronization information management module 24.
FIG. 4 is a configuration diagram of a packet of a new session creation request, a session participation request, and a session termination request issued to the client.

As shown in FIG. 4, a message issued from the display control module 15 to the synchronization monitoring module 16 includes a message type 110 and an address of the synchronous display content.

The message type 110 contains a code indicating whether the request is a synchronous content change request or a synchronous information confirmation request.
Although the synchronization information confirmation request is not essential, this function can issue a message for confirming the synchronization information to the synchronization monitoring module.

In the case of a synchronous content change request, a message is issued by specifying the address information 115 of the display content currently displayed in the synchronous information display window.

As shown in FIG. 5, a message issued from the synchronization monitoring module 16 to the display control module 15 includes a message type 120 and an address of synchronization information.

The code of the message type 120 is a notification of synchronization information. As the address 125 of the synchronization information, an address related to the synchronization information is specified.

As shown in FIG. 6, the packets sent from the synchronization monitoring module 16 to the synchronization information management module 24 are the communication header 130, the message type 132, the session ID 134, and the address 136 of the synchronization content / synchronization display content to be changed. .

The communication header 130 is a header for storing communication information of a packet. When the protocol is TCP / IP, it is a TCP / IP packet header.

The code of the message type 132 indicates whether the instruction is a synchronization information change instruction or an inquiry about the latest synchronization information.

The session ID 134 reports the session ID of the session in which the terminal participates. And synchronization information address 136. Address 136 of synchronous content / synchronous display content to be changed, message type 1
32 is the address of the synchronization information to be changed in the case of the synchronization information change instruction, and is the address of the display content displayed in the synchronization information display window 52 of the terminal itself when the packet content is an inquiry for the latest information.

As shown in FIG. 7, the packet sent from the synchronization information management module 24 to the synchronization monitoring module 16 is a communication header 140, a message type 142, and an address 146 of the synchronization information.

The communication header 140 is, for example, TCP / I
P is a packet header.

The code of the message type 142 is the latest synchronization information notification. The synchronization information address 146 is an address related to the synchronization information.

As shown in FIG. 8, a packet of each command issued from the synchronization monitoring module 16 to the synchronization information management module 24 is a communication header 150, a message type 152, and a session ID address 154.

The communication header is of the same type as that shown in FIGS. The code of the message type 152 is
A code indicating one of a new session creation request, a session participation request, and a session termination request is entered.

The session ID 154 is the ID of the target session. This field is valid for a session participation request and a session end request. In the case of a new session creation request, this field is left empty. It can be placed or omitted entirely.

Next, the operation of the client-server type information synchronization system according to the present embodiment will be described with reference to FIGS. FIG. 9 is a diagram showing a communication sequence exchanged between the client terminal and the WWW server according to the present embodiment. FIG. 10 is a schematic diagram illustrating an example of the session-related screen. FIG. 11 is a schematic diagram showing a synchronization information control window and a synchronization information display window. FIG. 12 is a flowchart illustrating the operation of the display control module 15. FIG. 13 is a flowchart showing the operation of the synchronization monitoring module 16. FIG.
6 is a flowchart showing a procedure for confirming a request of a display control module and performing a process in the operation of the synchronization monitoring module 16. FIG. 15 is a flowchart showing the operation of the synchronization information management module. FIG. 16 is a diagram showing a communication sequence exchanged between a client terminal and a WWW server according to the related art.

First, the communication sequence of the client-server type information synchronization system according to this embodiment will be described with reference to FIG.

As shown in FIG. 1, the communication model of this embodiment includes a terminal 1 and a terminal 2, and a WWW server 3
The ones that refer to and update the document via. Normally, both the terminal 1 and the terminal 2 refer to and update a document placed on the WWW server 3. However, here, for simplicity, the terminal 1 refers to the document and updates the document. It is assumed that the document is updated from 2.

The terminal 1 inquires of the WWW server 3 for synchronization information for the document being displayed at regular intervals (sequence 32) (sequence 30, sequence 33, sequence 36). When inquiring of the synchronization information for this document, the terminal 1 sends an inquiry to the WWW server 3 including the address information of the document currently displayed (managed as synchronization information). The inquiry about the synchronization information for this document is referred to as "polling". Also, a certain interval from the reception of the response to the next inquiry (sequence 3
The time of 2) will be referred to as a “polling interval”.

If there is no currently displayed synchronization information, such as immediately after the start of synchronization, it is determined that empty information is sent as it is (sequence 30).

On the other hand, the WWW server 3 returns a response to the inquiry.

At this time, the address of the display document of the terminal 1 sent at the time of the inquiry and the WWW server 3
The address displayed in the terminal 1 is compared with the address of the synchronization information managed in the step 1. If the address is different, the information displayed on the terminal 1 is not involved in the synchronization, and a response to that effect is returned ( Sequence 31).

When the address of the display document of the terminal 1 sent at the time of inquiry and the address of the synchronization information managed by the WWW server 3 are the same, a response is returned after waiting for a predetermined time (sequence 34). (Sequence 35). That is, in this case, the response of the WWW server 3 is intentionally delayed.

If a command for updating the synchronization information is received from the terminal 2 while waiting for a response (sequence 37), a response is immediately returned to the terminal 1 at that stage (sequence 38).
Update the synchronization information.

Referring to FIG. html is displayed, and in the case of the inquiry of the sequence 33, in the sequence 35, a response is received that the document has not been updated. And the sequence 36
When the inquiry is made, the document is transmitted from the terminal 2 during the waiting time. html was notified (sequence 37) that the document was immediately
B. html and a response is sent (sequence 3
8), the display of the terminal 1 html.

Here, the features of the present invention will be described in comparison with the communication sequence of a conventional client-server type information synchronization system.

In the client-server type information synchronization system according to the prior art shown in FIG. 16, the WWW server 3 immediately returns a response to a synchronization information inquiry from the terminal 1.

Inquiry of synchronization information issued from terminal 1 (sequence 300, sequence 320, step 340,
Step 360) is performed at the same polling interval (sequence 32) as in the example of the present embodiment in FIG. In response, the WWW server 3 returns the synchronization information managed immediately as a response (sequence 310, sequence 33
0, sequence 350, sequence 380).

In the conventional synchronization control method shown in FIG. 16, if the synchronization information update (sequence 370) is performed immediately before the synchronization information inquiry arrives at the WWW server, the update is transmitted to the terminal 1 as well. Although it is immediately transmitted as a response to the inquiry, as shown in the figure, the terminal 1
If the synchronization information is updated immediately after the inquiry from the terminal 1, the information of the terminal 1 will not be updated until the next inquiry. In this example, the sequence 360 first comes to the WWW server 3 after the update in the sequence 370.
Until the response of sequence 380 reaches the terminal 1, the updated synchronization information is not transmitted.

On the other hand, in the synchronization information control method of the present invention shown in FIG. 9, a response is waited for a certain period of time in response to an inquiry of synchronization information while updating is not performed (sequence 3).
4) In order to prepare for the update, the probability of avoiding a delay in update information transmission between polling intervals (sequence 32) increases. Further, as compared with the synchronization information control method shown in FIG. 16, the number of polls (inquiries) in the same time can be reduced, which is advantageous in that it can contribute to a reduction in network load.

Next, a user interface provided by the synchronous control system according to the present embodiment will be described with reference to FIGS.

In the information synchronization system of the present embodiment, the synchronization information is managed based on the concept of “session”. In order for the user to use this system, it is necessary to participate in a session.

FIG. 10 is an example of a screen for providing functions related to the session.

When the user starts the synchronous reference of the document or the like, or participates in the session in which the dialogue is performed using the synchronous reference of the document, the user interface as shown in FIG. 5 is provided. You.

A user who starts a session and a user who participates in an existing session load a session start / participation page with a browser. On this page, a new session generation button 40 used when a session is newly generated, a session information table 42 indicating a list of information on existing sessions, and the like are presented.

To generate a new session, a new session generation request is issued to the synchronization information management module 24 by clicking the new session generation button 40 with a mouse or the like.

On the other hand, when participating in an existing session, a session participation request is sent to the synchronous information management module 2 using link information attached to each session ID 43.
Issue to 4

When the user starts the synchronization reference of the document, the synchronization information is displayed and the control related to the synchronization is performed on the client terminal by the user interface as shown in FIG.

When a new session is requested by the user interface shown in FIG. 10, or when a response is returned from the synchronization information management module 24 of the WWW server 3 after the session participation request is issued, a new synchronization control Window 50 is opened. The synchronization information display window 52 is also opened, and plays a role of displaying the contents of the synchronized document until the session is ended.

The synchronization control window 50 includes a synchronization button 56 for initiating re-reading of synchronization information, an address specification column 55 for specifying an address of the synchronization information, and an address specification column 5.
5 has a change button 57 for making a request to change the synchronization information for the document at the address written in 5, and an end button 58 for requesting the end of the session. To implement each function, click each button with the mouse. Just do it.

Further, the position of the synchronization information display window 52 can be designated by the mouse cursor 53, the position of the content of the synchronization information is reported to the WWW server 3, and the synchronization information is controlled in relation thereto. good. FIG.
However, in this case, the reference and update of the document are performed by holding the coordinate position of the document in the synchronization information. By doing so, the synchronization information can be referred to and updated even with respect to the position of the document in the page, so that finer synchronization control can be performed.

Next, the module-level processing of the client-server type information synchronization system of this embodiment will be described.

First, the operation of the display control module 15 will be described with reference to FIG.

The display control module 15 in the client terminal 10 is provided with the synchronization control window 5 shown in FIG.
The following processing is performed until the synchronization end request 60 is issued, for example, by clicking the end button 58 of 0 (step 60).

Change button 5 of synchronous control window 50
7 is clicked and a synchronous content change request is issued (step 62), the display control module 15
A synchronization content change request is issued as a message shown in FIG. 4 to the synchronization monitoring module 16 in the same client terminal 10 together with the address information of the change content specified in the address specification column 55 or the like of the synchronization control window. (Step 63).

Similarly, when a synchronization information confirmation request is issued (step 65), for example, when the synchronization button 56 of the synchronization control window 50 is clicked, the synchronization information confirmation request is sent to the synchronization monitoring module 16. It is issued as the message shown in FIG. 4 (step 66).

On the other hand, when the notification of the synchronization information is received from the synchronization monitoring module 16 (step 68), the display content of the synchronization information display window 52 is updated (step 6).
9).

Next, the operation of the synchronization monitoring module 16 will be described with reference to FIG.

The synchronization monitoring module 16 acquires a session ID from the synchronization information management module 24 at the time of starting or at the time of starting synchronization (step 70). As described above, the synchronization monitoring module 16 in the client terminal 10
Install it in advance, or execute WWW server 3
However, if the synchronization monitoring module 16 is downloaded from the WWW server 3, the synchronization monitoring module 16 may execute the response from the synchronization information management module 24 in response to the session start request or the session participation request. The session ID is passed as an argument when the synchronization monitoring module 16 is downloaded and activated.

At the time of start-up or synchronization start, the polling interval monitoring timer for monitoring the polling interval for inquiring the synchronization information management module 24 of the synchronization information is initialized with the polling interval time, and the synchronization information is immediately set. Is referred to (step 72).

Thereafter, the synchronization monitoring module 16 performs the following processing until it receives a synchronization end request from the display control module 15 on the same client terminal 10 or the synchronization information management module 24 on the WWW server (step 74). Perform

First, a request from the display control module is confirmed and a procedure for processing is executed (step 7).
6). The details of the procedure will be described with reference to FIG.

If the value of the polling interval monitoring timer has reached the polling interval time (step 80),
The synchronization monitoring module 16 sends an inquiry about the latest synchronization information to the synchronization information management module 24 in the WWW server 3,
Issued as the packet shown in FIG.
1) Stop the polling interval monitoring timer (step 82).

On the other hand, from the synchronization information management module 24,
When the latest synchronization information is received by the packet shown in FIG. 7 (step 85), the address of the received synchronization information is compared with the address of the information currently displayed on the browser 52 (step 86). If they are different, an address notification and a display update instruction are issued to the display control module 15 as messages shown in FIG. 5 in order to newly display the received synchronization information (step 87).

When the synchronization information is received from the synchronization information management module 24, the polling monitoring timer is initialized and the timer is started at the last stage (step 88).

In this flow, the operation of the synchronization monitoring module 16 is treated as a series of flows.
Is described as being executed by one process. However, confirmation and processing of a request from the display control module in step 76, polling transmission processing in steps 80 to 82, and polling response reception in steps 85 to 88 are performed. The processing may be performed by independent threads.

Next, confirmation and processing of a request from the display control module 15, which is one procedure of the processing of the synchronization monitoring module described with reference to FIG. 13, will be described with reference to FIG.

Confirmation and processing of the request from the display control module 15 correspond to step 76 shown in the flowchart of the synchronization monitoring module 16.

When there is a request for changing the synchronization content from the display control module 15 according to the message shown in FIG. 4 (step 90), a synchronization content change instruction is transmitted to the synchronization information management module 24 (step 92). .

When the display control module 15 requests a confirmation of the synchronization information from the message shown in FIG. 4 (step 94), the address of the synchronization information held in the synchronization monitoring module 16 is displayed. Module 1
5 is notified (step 96).

Finally, the operation of the synchronization information management module 24 on the WWW server 3 will be described with reference to FIG.

Synchronization information management module 24 on WWW3
Performs the following processing until an instruction to end the program is issued (step 100).

By operating the session-related screen as described with reference to FIG. 10, a packet for a new session creation request or a session participation request shown in FIG. 8 is sent to the synchronization information management module 24, and when the packet is received, (Step 101), as a response to the request,
A form (page) prompting the activation of the synchronization control window 50 described above is returned to the client terminal (step 102).

When the synchronization information change instruction is received by the packet shown in FIG. 6 (step 103), the contents of the designated session in the synchronization information management table 25 are updated (step 104).

On the other hand, when the inquiry of the latest information is received by the packet shown in FIG. 6 or when the response is waiting (step 105), the synchronization information of the inquired session is When updated (step 106), the updated synchronization information is immediately returned as a response by the packet shown in FIG. 7 (step 10).
8). If the synchronization information has not been updated (step 106), it is checked whether or not the time elapsed since the reception of the inquiry has reached the response holding time (step 107). If it has reached, the synchronization information corresponding to the session managed in the synchronization information information management table 25 is returned as a response as a packet shown in FIG. 7 even if the synchronization information has not been updated (step 108). ).

The determination as to whether or not the synchronization information has been updated depends on the address of the display information sent in the inquiry of the synchronization information and the synchronization information corresponding to the session managed in the synchronization information management table 25. This is done by comparing with the address.

In this flow, the synchronization information management module 2
4 is treated as a series of flows, and the synchronization information management module 24 is described as being executed in one process. However, the processing for generating a new session or performing a session participation request performed in steps 101 and 102 includes:
Processing for the synchronization information change instruction performed in steps 103 and 104, and steps 105 to 108
The response processing to the synchronization information inquiry performed in step (1) may be performed by independent threads.

[0103]

According to the present invention, when an information synchronization system is constructed using a request-response communication protocol in the Internet environment, the update information at the time of updating the synchronization information is reduced while suppressing the load on the network and the terminal. Can be provided for promptly reflecting the information on each terminal.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a state transition when a document is referenced and updated in a client-server type system.

FIG. 2 is a functional configuration diagram of a client terminal according to the embodiment.

FIG. 3 is a functional configuration diagram of a WWW server 3 according to the embodiment.

FIG. 4 is a configuration diagram of a message content issued from the display control module 15 to the synchronization monitoring module 16;

FIG. 5 is a configuration diagram of a message content issued from the synchronization monitoring module 16 to the display control module 15;

FIG. 6 is a configuration diagram of a packet sent from the synchronization monitoring module 16 to the synchronization information management module 24.

FIG. 7 is a configuration diagram of a packet sent from the synchronization information management module to the synchronization monitoring module.

FIG. 8 is a configuration diagram of a packet of a new session creation request, a session participation request, and a session termination request issued from the synchronization monitoring module 16 to the synchronization information management module 24.

FIG. 9 is a diagram showing a communication sequence exchanged between a client terminal and a WWW server according to the embodiment.

FIG. 10 is a schematic diagram illustrating an example of a session-related screen.

FIG. 11 is a schematic diagram showing a synchronization information control window and a synchronization information display window.

FIG. 12 is a flowchart showing an operation of the display control module 15;

FIG. 13 is a flowchart showing the operation of the synchronization monitoring module 16;

FIG. 14 is a flowchart showing a procedure for performing a request confirmation and processing of a display control module in the operation of the synchronization monitoring module 16;

FIG. 15 is a flowchart showing the operation of the synchronization information management module.

FIG. 16 is a diagram showing a communication sequence exchanged between a client terminal and a WWW server according to the related art.

[Explanation of symbols]

3 WWW server, 10 client terminal, 15 display control module, 16 synchronization monitoring module, 24
Synchronization information management module, 25... Synchronization information management table.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tohru Hoshi 1099 Ozenji Temple, Aso-ku, Kawasaki City, Kanagawa Prefecture Inside System Development Laboratory, Hitachi, Ltd. Information Technology F-term (reference) 5B082 GA15 GB02 5K034 AA01 BB06 DD02 EE11 FF08 HH63 KK29 QQ08 SS03

Claims (7)

[Claims] 1. A client-server type information synchronization control method in which synchronization information is centrally managed by a server, and the client refers to and updates the synchronization information.
A synchronization information acquisition request process for periodically inquiring the server of the latest synchronization information; a synchronization information update process for updating the synchronization information managed by the server from the client; and a synchronization executed by the server. The synchronization information management process, when receiving a synchronization information acquisition request from the client, compares the synchronization information specified in the request with the synchronization information managed by the server. Then, when both are different, the synchronization information managed by the server is immediately returned to the client as a response. On the other hand, when both are the same, a certain time elapses, or A response to the client is held until the synchronization information managed by the server is updated, and a certain time passes or the server manages the response. A client-server type information synchronization control method, wherein the synchronization information managed by the server is immediately returned to the client when the synchronization information is updated. 2. A communication protocol between the client and the server, the communication protocol being HTTP (Hyper Text Transfer).
r protocol), a client-server type information synchronization control method. 3. In a client-server type information synchronization system in which synchronization information is centrally managed by a server and a client references and updates the synchronization information, the system specifies synchronization information currently held by the client. ,
A synchronization information acquisition request unit for periodically inquiring the server of the latest synchronization information; a synchronization information updating unit for updating the synchronization information managed by the server from the client; and a synchronization executed by the server. The synchronization information management means, when receiving a synchronization information acquisition request from the client, compares the synchronization information specified by the request with the synchronization information managed by the server. Then, when the two are different, the synchronization information managed by the server is immediately returned to the client as a response. On the other hand, when the two are the same, a certain time elapses, or Until the synchronization information managed by the server is updated, the response to the client is held, and after a certain period of time elapses, the synchronization managed by the server is updated. A client-server type information synchronization system for immediately performing a process of returning synchronization information managed by the server to the client as a response when the period information is updated. 4. The information synchronization system according to claim 3, wherein HTTP is used as a communication protocol between said client and said server. 5. The information to be synchronized is information of an electronic dialogue performed based on a browser.
Information synchronization system as described. 6. The synchronization information centrally managed by the server,
6. The information synchronization system according to claim 3, wherein the address indicates an address of a document to be synchronously referenced. 7. Synchronization information centrally managed by the server,
6. The information synchronization system according to claim 3, wherein the information is a coordinate value of a cursor indicating a position inside a document that can be displayed on the client.