JP2003157225A - Server - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a cooperation work using a shared image, a shared red pen, browser cooperative control, a Java program, etc., with a plurality of browsers by providing servers such as an awareness server and a collaboration server in addition to browsers and a WWW server concerning a server connected to a plurality of clients through a network. SOLUTION: This server is provided with a sharing means for holding client information, a means for transmitting a control window to a client on the basis of a request from the client, a URL receiving means for receiving a URL transmitted from the control window of the client, and a means for referring to the sharing means and transmitting the URL to all clients in order to display shared information in the shared window of all of the clients if the URL receiving means receives the URL.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a server for connecting a plurality of browsers and a WWW server to a network for collaborative work.

[0002]

2. Description of the Related Art Conventionally, on the Internet, a WWW server is accessed from a browser via the Internet, a page having a predetermined URL is returned, and the page is displayed on the screen.
A request for a page of another URL is made on the screen, the page is returned after being returned, and the page (information) of the WWW server is referred to.

[0003]

However, in the above-mentioned browser and WWW server system, a plurality of users operate the browsers to display a shared screen and display mutual operations in real time on other shared screens. There is a problem that a pointing display such as a red pen cannot be displayed / moved in real time on a shared screen, and a Java program or the like cannot be used mutually for collaborative work.

The present invention solves these problems.
In addition to a browser and a WWW server, servers such as an awareness server and a collaboration server are provided, and a shared screen, a shared red pen, cooperative control of browsers, and collaborative work by Java programs are realized by a plurality of browsers.

[0005]

[Means for Solving the Problems] Means for solving the problems will be described with reference to FIG. In FIG. 1, the WWW server 1 downloads the requested URL page to a browser (browser operating on the client 1) and displays the URL page.

The sharing means 3 is provided on the server and displays the sharing screen on the screen of the browser operating on the client 7. The coordinating means 5 is provided on the server, and causes the browser operating on the client 7 to cooperate with the application.

The client 7 is a computer system that operates a browser. Next, the operation will be described.
The browser running on the client 7 is the WWW server 1
After displaying the shared screen and the control screen that are sent by sending the request for the shared screen to the server, the shared means 3 operating on the server is requested to request all the client names, and all the returned client names are displayed on the control screen. , And each browser displays the shared screen and the names of all the clients performing other collaborative work on the control screen.

At this time, the sharing means 3 operating on the server in response to a request for a page for cooperation from any browser.
Responds to all browsers that are currently connected and displays it on the shared screen.

Further, in response to one of the browsers displaying the red pen on the shared screen and transmitting the object to the sharing means 3 operating on the server, the sharing means 3 is connected to another browser at present. The object is sent to and displayed on the shared screen.

Further, in response to the fact that the red pen displayed on the shared screen of the browser has been moved on any of the browsers, the sharing means 3 for operating the moving information of the red pen on the server.
In response to the transmission, the sharing means 3 transmits the movement information of the red pen to another browser currently connected to move the red pen on the shared screen.

Further, the browser sends a request for a shared screen for cooperative work to the WWW server 1, displays the cooperative app on the shared screen for cooperative work returned, and operates the operational information of the cooperative app on the server. The information is transmitted to the coordinating means 5, and the coordinating means 5 causes another browser that is currently connected to transmit the operation information of the cooperation application, and the operation processing is performed according to the operation information of the cooperation application.

Therefore, in addition to the browser and the WWW server, a server such as an awareness server that operates the sharing unit 3 and a collaboration server that operates the cooperation unit 5 is provided, and a shared screen, a shared red pen, and a browser are shared by a plurality of browsers. It is possible to realize the cooperative control of, and the cooperative work by the Java program and the like.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment and an operation of the present invention will be sequentially described in detail with reference to FIGS.

FIG. 1 shows a system configuration diagram of the present invention.
In FIG. 1, the WWW server 1 downloads the URL page requested by the browser operating on the client 7 and displays the URL page.

The awareness server 2 is a server that displays shared information and the like on a shared screen or a control screen of a browser operating on the client 7. Here, the shared means 3 is operated. Is.

The sharing means 3 performs various sharing processes (such as displaying a sharing window and displaying a red pen on the sharing screens of all browsers and moving displays) on the sharing screens and control screens displayed by a plurality of browsers. ) Is performed (which will be described later with reference to FIGS. 2, 5, 8 and the like).

The collaboration server 4 is a server that causes an application to cooperate with each other on the screen of a browser that operates on the client 7. Here, the collaboration server 4 operates.

The coordinating means 5 is for coordinating the applications on the shared screen of each browser. The network 6 is a network for transmitting and receiving data between the server and other servers and clients.

The client 7 is a computer system that operates a browser, and here, for displaying a URL page (shared screen, control screen, etc.) and inputting various instructions and the like on the screen. It is a thing.

Next, the display of the shared screen and the control screen in the configuration of FIG. 1 will be described in detail in the order of FIG. FIG. 2 shows an operation explanatory diagram (display of a shared screen / control screen) of the present invention. Here, the clients H1 and H2 are the clients 7 of FIG. 1, the awareness server is the sharing means 3 of the awareness server 2 of FIG. 1, and the WWW server is the WWW server 1 of FIG.

In FIG. 2, S1, S1 ', S2, S3
Activates the client, the awareness server 2, and the WWW server 1, respectively, and brings them into an operating state. In S4, the client H1 makes a service request. As a result,
The browser of the client H1 of 1 transmits the URL of the initial page to the WWW server via the network 6.

In S5, the WWW server 1 which has received the URL of the initial page in S4 transmits the initial page. S6 is
Following the transmission of the initial page in S5, the control page is transmitted.

In S7, the browser of the client H1 is S
The initial page sent in step 5 is received and displayed. S8
Displays the control page transmitted by the browser of the client H1 in S6. These S7, S
8, the HTML document (HTML of shared window and control window as shown in FIG.
(Document), and displays the shared window 12 at the bottom and the control window 11 at the top, as shown in FIG.

In step S9, a socket is used for connection. This transmits the packet of FIG. 4A described later (transmitted to the awareness server 2 of FIG. 1). In S10, it is determined whether the awareness server 2 has connected to the client. Here, since the packet transmitted in S9 has been received and connected, the determination result is YES, and the process proceeds to S11. On the other hand, in the case of NO, it stands by.

In S11, since it is determined that the client (browser) is connected in YES in S10, the host names (H1, H2 ...) Are transmitted to all the clients. S12
Receives all the client names sent by the client H1 in S11, and displays H1, H2 in the control window.
Is displayed. For example, each host (client) name is displayed in a unique color on the left side of the control window 11 of FIG. 6 described later with an icon (●) (displayed with a ● of a unique color corresponding to H1 and H2. The received H2 may be displayed on one's own H1 after receiving the host name of))).

In S13, the client H2 receives all the client names transmitted in S11 and displays H1 and H2 in the control window. For example, on the left side of the control window 11 of FIG. 6 to be described later, ● is displayed in a unique color for each host (client) name (Displayed in ● of a unique color corresponding to H1 and H2 (note that host names other than your own) The received H1 may be displayed on one's own H2 after the transmission))).

By the above, the client (browser)
When the URL of the initial page is transmitted to the WWW server 1 at startup, the initial page and the control page (HTML document of FIG. 3) are downloaded, and as shown in FIG. 6, the control window 11 is on the upper stage and the shared window 12 is on the lower stage. Further, the control window 11 is displayed, and in response to the display, the awareness server 2 is automatically connected, and the host names of all clients currently connected to the awareness server 2 are downloaded to control the client (browser). All client names H1 and H2 displaying the shared window on the window 11
Is displayed. As a result, as shown in FIG. 6, the control window 11 is displayed in the upper stage and the shared window 12 is displayed in the lower stage on the browsers of all the clients that have issued the shared window request.
It is possible to display various information such as a shared host name in 1 and shared information common to all in a shared window in real time.

FIG. 3 shows an example of the structure and contents of the WWW page of the present invention. This is the WW in S5 and S6 of FIG.
H returned from the W server 1 to the client browser
In the example of the TML document 10, the upper part is an HTML document displaying the control window 11, and the lower part is an HTML document displaying the shared window 12. Also,
HTML document (inde) for displaying two frames together (control window and shared window)
x. It was also sent back to the browser.

FIG. 4 shows an explanatory diagram (transmission data) of the present invention. FIG. 4A shows an example of transmission data (packet) when connecting with a socket. This is shown in FIG.
This is an example of transmission data (packet) transmitted from the browser of the client to the WWW server 1 in S9 of FIG.

-Sender: IP address of awareness server-Sender: IP address of client H1-Sender: Mac address of awareness server-Sender: Mac address of client H1-Data: None or more When the client H1 creates and transmits the transmission data of, and the awareness server 2 receives the transmission data, the sharing unit 3 is activated, and the processing after YES in S10 of FIG. 2 described above is started to be executed.

FIG. 4B shows an example of transmission data (packet) for host name transmission from the awareness server.
This is the awareness server 2 in S11 of FIG.
This is an example of transmission data (packet) transmitted from the client to each client, and the following data shown in the figure is set in the client H1.

-Sender: IP address of client H1-Sender: IP address of awareness server-Sender: Mac address of client H1-Sender: Mac address of awareness server-Data-Host display request: -H1: ON-H2: ON Similarly, the following data shown in the figure is set in the client H2.

-Sender: IP address of client H2-Sender: IP address of awareness server-Sender: Mac address of client H2-Sender: Mac address of awareness server-Data-Host display Request: ・ H1: ON ・ H2: ON When the awareness server 2 creates and transmits the above transmission data and the clients H1 and H2 receive it, the processing of S12 and S13 in FIG. 2 described above starts execution. Then, the shared host names (client names) H1 and H2 are displayed on the control window 11 of FIG.

4C and 4D show examples of transmission data (packets) of red pen information. This is the "red pen" displayed on the shared window according to the order of Fig. 8 described later.
Is an example of transmission data when the object and the display coordinates are transmitted to the awareness server 2 ((c) in FIG. 4) and the awareness server 2 broadcasts to all clients (here, H2) (FIG. 4). 4 (d)).

FIG. 4C shows an example of "red pen" transmission data transmitted from the client H1 to the awareness server 1. Here, the following data shown in the figure are set.・ Sender: IP address of awareness server ・ Sender: IP address of client H1 ・ Sender: Mac address of awareness server ・ Sender: Mac address of client H1 ・ Data ・ Red pen request: ・ Shape: ・ Coordinates : X coordinate and Y coordinate. Type of ON / OFF: ON or OFF The client H1 creates and transmits the above transmission data, and the awareness server 2 receives it.

FIG. 4D shows an example of the transmission data of the "red pen" transferred by the awareness server 1 to the client H2. Here, the following data shown in the figure are set.・ Sender: IP address of client H2 ・ Sender: IP address of awareness server ・ Sender: Mac address of client H2 ・ Sender: Mac address of awareness server ・ Data ・ Red pen request: H1 ・ Form: ・Coordinates: X coordinates and Y coordinates. Type of ON / OFF: ON or OFF. The awareness server 2 creates the above transmission data, transmits it to another client H2, and the client H2 receives it. It is possible to create a red pen on the shared window of the browser, send the information (shape, coordinates) to all other clients, and display it in real time on the shared window.

FIG. 4C shows an example of transmission of information (scroll bar position information) when scrolling on the shared screen. This makes it possible to scroll the screen displayed on the shared screen.

FIG. 5 shows an operation explanatory diagram (shared) of the present invention. This is the HTML of FIG. 3 according to the order of FIG.
In a state where the control window 11 is displayed in the upper part of the browser of the client in the document, the shared window 12 is displayed in the lower part, and the shared host names (client names) H1, H2, etc. are displayed on the control window 11,
This is a procedure for displaying shared information in a shared window.

In FIG. 5, S21, S22, S23
Indicates that the clients H1 and H2 and the awareness server 2 have already been activated and are operating. In S24, in addition to the WWW server 1, as a WWW server, W2 is activated and brought into an operating state.

In S25, the URL is input on the control window 11 on the browser of the client H1 (the UR for cooperation on the control window 11 in FIG. 6).
Enter the URL in the L input field). Then, the URL is transmitted.

In step S26, it is determined whether the awareness server 2 has received the URL transmitted in step S25. Y
In the case of ES, the process proceeds to S27. If NO, wait.

In S27, a predetermined URL is obtained when YES in S26.
Since it was found that the URL was received, the URL is sent to all clients (UR of the specified shared page).
Send L).

In S28, the client H1 receives the URL transmitted in S27 and makes a display request to the shared window. In S29, the URL is sent to the WWW server 1 in response to the request to display the shared window in S28.
Send a request for the page.

In S30 and S31, similarly to S28 and S29, the client H2 receives the URL transmitted in S27, makes a display request to the shared window, and transmits a request for the page of the URL to the WWW server 1.

In S32, the WWW page (page designated by URL (HTML document)) is returned in response to the page request transmitted in S29 and S31. S3
In S3 and S34, the pages are displayed in the shared window on the clients H1 and H2 (the HTML document of the received page is displayed on the shared window 12 of the browser). As a result, the same content to be shared is displayed in the shared window 12 of the browser of each client, as shown in the lower part of FIG. 6 described later.

As described above, when the client, for example, the client H1 inputs the URL for cooperation, the UR
L is sent to the awareness server 2 and sends it to all the clients, and each client requests the WWW server 2 to receive the HTML document reply of the page, and the shared content (cooperation content) on each shared window Can be displayed respectively.

The WWW page displayed as the shared content is the WW in which the initial page and the control page are stored.
WWW which is an arbitrary WWW site different from the W server 1
Any WWW page of the server W2 can be referenced.

FIG. 6 shows an example of the screen of the present invention (initial page and control page). Here, the upper part is the control window 11, and the lower part is the shared window 12. The control window 11 and the shared window 12 are realized by displaying the above-described HTML document 10 of FIG. 3 received by each client from the WWW server 1. Each item / column is as entered in the outside of the figure.

FIG. 7 shows a screen example of the WWW cooperation function of the present invention. Here, the left side is the browser of the client H1 (for example, Internet of Windows 95 (trademark)).
An example displayed on etExplorer 4.0 (trade name) is shown, and the right side is the browser (Ma) of the client H2.
c NetscapeNa with OS 8.1 (trademark)
The example displayed on the "Vigator" (trademark name) is shown, and the same URL (JAIST homepage) is referred to in real time on different browsers operating on different OSs (JAIST is the university name (Hokuriku). Advanced Science and Technology Graduate University)).

FIG. 8 is a diagram for explaining the operation of the present invention (red pen display / movement). In FIG. 8, in S41, the client H1 displays a menu. In S42, the object displayed as the red pen is designated.

In step S43, the object is displayed. These S41, S42, and S43 display a pop-up menu, for example, as shown in FIG. 9A, in which a figure (object) to be used as a red pen, for example, an arrow is designated (selected) to be displayed. As shown in the lower right arrow, the WWW page displayed in the shared window is overlaid and displayed. Then, the object information of the red pen (information consisting of object and coordinates) is transmitted.

In S44, the awareness server 2 which has received the object information transmitted in S43 transmits the object information to the clients other than the transmission source. S45
Here, a client other than the transmission source, for example, the client H2 receives the object information transmitted in S44, and based on the object information as shown in (b) of FIG. Display the "red pen" on the same shape and at the same position.

In S46, the client H1 moves the object (red pen). The movement information is transmitted to the awareness server 2. In S47, the awareness server 2 transmits the movement information to the clients other than the transmission source.

In S48, the client H2 displays the movement of the object. As described above, when a client H1 selects and displays an object that becomes a "red pen", the object information is automatically transmitted and the awareness server transfers the object information to all the other clients in the shared state. The client displays the red pen based on the received object information, and when one of the clients moves the red pen, the movement information is received by other clients via the awareness server and the red pen is moved. It becomes possible. As a result, it becomes possible to display a red pen on the shared window of the client and point the same position for data communication with each other, or to point out the counting points, to use for questioning and conference support.

FIG. 9 shows a screen example (red pen) of the present invention. FIG. 9A shows a state in which a pop-up menu appears on the WWW page of a client, an arrow, a line drawing, or text is input, and "red pen" is designated (selected).

In FIG. 9B, an object input over a network (such as the Internet) is displayed,
It also shows how the movement of the object follows. Here, the red pen is designated and displayed and moved on the shared window of the client of FIG. 9A, and the red pen is displayed and moved following the shared window of the client of FIG. 9B. As shown, the pop-up menu is also displayed on the shared window in FIG. 9B,
You can enter the red pen object and share it with all clients to display it. The input object is identified for each client by the color uniquely assigned by the awareness server 2. Objects that are input and operated by each client are displayed in real time. Although the object input by the client H1 is displayed on the shared screen of the client H2 and the movement and movement of size are transmitted, the object cannot be operated on the client H2 side.

FIG. 10 shows an example of the screen of the present invention (function of displaying a plurality of shared windows). Here, an example in which three shared windows are provided on the browser of the client is shown. These shared windows are referred to as shared windows shared by all clients, shared windows shared by clients in a group, and shared windows shared by individuals. This is done by specifying all the clients to be shared, specifying a specific group, specifying a specific client name, etc., and displaying multiple specified shared windows to enable information sharing among clients in the share. It becomes possible to perform shared display of.

FIG. 11 is a diagram for explaining the operation of the present invention (cooperative work). This is to display the collaborative application on the browser sharing window of the shared client, and perform the collaborative transaction processing by the collaborative application (for example, the collaborative transaction processing that collaborates the transaction processing described in the Java program running on the browser). It shows a procedure for performing.

In FIG. 11, in step S50, the collaboration server 4 is activated and put into operation. In S51, the client H1 requests a URL for cooperative work. This request is transmitted to the awareness server 2.

At S52, the awareness server 2 that has received the request at S51 broadcasts the URL. S53 is S5
The client H1 having received the broadcast of 2 makes a display request to the shared window.

In step S54, a page request is made to the WWW server in response to the display request to the shared window in step S53.
In S55 and S56, similarly to S53 and S54, the client H2 makes a display request to the shared window, and in response to the display request to the shared window, makes a page request to the WWW server.

In S57, the WWW server 1 receiving the page request in S54 and S56 transmits the WWW page for cooperative work. In S58, the client H1 receives the WWW page of the cooperative work transmitted in S57, and displays the WWW page and the cooperative application.

Similar to S58, in S59, the client H2 receives the WWW page of the cooperative work transmitted in S57 and displays the WWW page and the cooperative application. S
At 60, here, the client H2 gives an operation instruction to the cooperative application. The operation information of this operation instruction is transmitted to the collaboration server 4.

In S61, it is determined whether the collaboration server 4 is the data of the port addressed to itself. If yes,
After receiving the transmission data addressed to itself, the process proceeds to S62. If NO, wait.

In S62, the operation information of the cooperative application received in YES in S61 is transmitted to all clients. Here, the operation information of the cooperative application may be transmitted by any method of all the clients including myself or all the clients other than myself.

In S63, the transmission source client H2 receives the operation information of the cooperative application, and starts the operation processing of the cooperative application. In S64, the client H1 other than the transmission source receives the operation information of the cooperative application, and starts the operation processing of the cooperative application.

As described above, a client makes a URL request for collaborative work, displays a page for collaborative work downloaded from the WWW server 1 and displays a collaborative app (one or a collaborative app selected from arbitrary ones). It is possible to transmit the operation information to all the clients or all the clients except the sender via the collaboration server 4 in response to the operation instruction of the cooperative application, and start the cooperative work on the shared window of each client. Become.

FIG. 12 shows a screen example (cooperative editor) of the present invention. Here, the browser H1 on the left side is a browser that operates on the client H1, and is, for example, Net.
It is the model 44.03 (ja) (trade name). The browser H2 on the right side is a browser that operates on the client H2, and is, for example, Microsoft Internet.
et Explorer 4.0 (trade name). In this way, the cooperative application (applet described in the Java language) can work in cooperation on different browsers, the left browser H1 and the right browser H2. In the illustrated example, the editors work together to display the human-powered text on either the left or right side to everyone. Changes in the font menu are also coordinated, and font size and type are also coordinated. Also,
It is also possible to specify a URL, read a file on the server, and cooperate with each other to perform collaborative work.

In the present embodiment, the WWW server 1, the awareness server 2 and the collaboration server 4 are described separately for convenience of description, but the awareness server 2 and the collaboration server 4 are provided on the conventional WWW server 1. Function may be provided, or another server may be provided with the functions of the awareness server 2 and the collaboration server 4.

FIG. 13 is a diagram for explaining the operation of the present invention (detection of disconnection status). In step S71 in FIG. 13, H1 which is one of the clients connected to the system terminates the browser, exits the control page for sharing and refers to another WWW page, and terminates the cooperative system.

In S72, the socket connected to the awareness server 2 is disconnected due to the termination of the system.
In S73, it is determined whether the awareness server 2 has disconnected from the client. Here, since the socket has been disconnected in S72, the determination result is YES, and the process proceeds to S74. On the other hand, NO
If, then wait.

In S74, since it is determined that the client H1 has been disconnected, the host names (H2 ...) Currently in the standby state are transmitted to all the clients. S75
Receives the host name in the current connection state and displays H2 in the control window.

FIG. 14 is a diagram for explaining the operation of the present invention (browser control, scrolling). In FIG. 14, S81
Operates the scroll screen of the WWW page of the shared window by pressing the scroll button in FIG. 6 with the controller of the control window.

In S82, the screen of the shared window is scrolled according to the scroll amount and direction input in S81. Then, the scroll information shown in FIG. 4E (in this case, the current scroll position of the shared screen) is transmitted to the awareness server 2.

In S83, the scroll information received from the client H1 is sent to the client H2 other than the sender.
Broadcast to all connected clients. In S84, according to the scroll information received from the awareness server 2,
Scroll the screen of the shared window.

Similarly to the above, the information that the size of the browser has been changed, that the icon has been entered, that the WWW page has been loaded, that the frame has been changed, and that the position information of the browser has been transmitted. The browser state is shared.

[0077]

As described above, according to the present invention,
In addition to the browser and the WWW server, a server such as an awareness server that operates the sharing means 3 and a collaboration server that operates the cooperation means 5 is provided. Therefore, a shared screen and a shared red pen are shared by a plurality of browsers. , And Java programs can be used for collaborative work. With these, the browser can only refer to the information on the page of the server in the past, but by providing the sharing means 3 and the cooperation means 5 on any server, a shared screen (shared window) is displayed on each browser to display information. Can be shared and displayed, a common position can be indicated with a red pen, and the browser can be controlled cooperatively to have conversations, etc., and real-time cooperation apps (applets, etc.) can be displayed on the cooperative screen (shared cooperative window). It became possible to perform collaborative work by displaying on. Further, not only the shared display but also input from the shared screen can be performed, and the input status can be mutually transmitted and displayed by each client to realize bidirectional sharing.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of the present invention.

FIG. 2 is an operation explanatory diagram (display of a shared screen / control screen) of the present invention.

FIG. 3 shows an example of the structure and contents of a WWW page according to the present invention.

FIG. 4 is an explanatory diagram (transmission data) of the present invention.

FIG. 5 is an operation explanatory diagram (shared) of the present invention.

FIG. 6 is a screen example (initial page and control page) of the present invention.

FIG. 7 is a screen example of a WWW cooperation function of the present invention.

FIG. 8 is an operation explanatory diagram (red pen display / movement) of the present invention.

FIG. 9 is a screen example (red pen) of the present invention.

FIG. 10 is an example of a screen of the present invention (function of displaying a plurality of shared windows).

FIG. 11 is an operation explanatory view (cooperative work) of the present invention.

FIG. 12 is a screen example (cooperative editor) of the present invention.

FIG. 13 is a diagram for explaining the operation of the present invention (detection of disconnection status).

FIG. 14 is an operation explanatory diagram (browser control, scroll) of the present invention.

[Explanation of symbols]

1: WWW server 2: Awareness server 3: Sharing method 4: Collaboration server 5: means of cooperation 6: Network 7: Client 10: HTML document 11: Control window (control screen) 12: Shared window (shared screen)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Susumu Kunifuji             2-13 Takao Minami, Kanazawa City, Ishikawa Prefecture F-term (reference) 5B069 CA02 CA07 CA13 CA19 GA03                       LA03                 5B085 AA08 BA06 BG02 BG07 CE03                       CE06

Claims (3)

[Claims] 1. A server connected to a plurality of clients via a network, a sharing means for holding information of the client, a means for transmitting a control window to the client based on a request from the client, and a client. URL receiving means for receiving the URL transmitted from the control window, and when the URL receiving means receives the URL, it refers to the sharing means and displays the shared information in the shared windows of all clients. U to the client
A server for transmitting the RL. 2. A red pen information receiving means for receiving from the client information about a red pen that cannot be operated by another terminal displayed on a shared window of the client, and the red pen information receiving means stores information about a red pen. The server according to claim 1, further comprising: a transmission unit that, when received, refers to the sharing unit and transmits information regarding the red pen to all clients. 3. The server according to claim 2, wherein the information relating to the red pen is information indicating that the red pen has been moved, resized, or the number of red pens has been increased or decreased.