Electrical computers and digital processing systems: multicomput – Distributed data processing – Client/server
Reexamination Certificate
1998-09-21
2001-10-16
Rinehart, Mark H. (Department: 2756)
Electrical computers and digital processing systems: multicomput
Distributed data processing
Client/server
C709S202000, C709S217000, C709S219000
Reexamination Certificate
active
06304894
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a technology for changing functions that can be supplied to client programs in a client server system such as, for example, an X window system, without amending an existing server program. While the present invention is discussed in the client server system environment, it should be understood that this invention can be applied to any address-type interface between any two programs.
A conventional system is known for realizing desired functions by linking a server program with client programs. In such a system, the server program notifies each client program of usable functions. A client program requests a specific function selected from among the functions notified from the server program. Upon receiving the request, the server program supplies the function to the client program.
The system described above is generally referred to as a client server system (CSS). From here on, such a client server system will be explained by way of an X window system, which is a client server type window system.
In an X window system, the server program (X server) displays a window and draws patterns in the window displayed on a display screen of a computer that is executing the server program in response to a request from a client program (application program). In addition, the server program, when receiving a user instruction entered by an input device, notifies the client program of the received instruction.
On the other hand, the client program asks the server program to supply various functions for displaying a window, drawing patterns in the window, etc. on the display screen. In addition, the client program executes desired processings according to the contents of a user instruction, etc. notified from the server program. As such, the X window system allows the server program to be linked with client programs to realize a graphical user interface (GUI) which is used by users to communicate with the computer.
In a conventional client server system, the functions supplied by the server program are usually fixed. In addition, each client program is created on the premise that the client program will use such fixed functions of the server program. Consequently, in a client server system in which the server program notifies each client program of usable functions and each client program requests its desired functions selected from among the functions notified from the server program, it is impossible for the client program to increase and reduce usable functions without amending the server program. Thus, the system has a problem that it is not flexible for such operations.
For example, when a new hardware appears, a client program will want to increase existing usable functions to make maximum use of the hardware ability. In such a case, in the case of the conventional client server system, functions that are not supplied originally by the server program must be added to the server program and accordingly the server program must be amended.
Furthermore, for some functions supplied by the server program to client programs, client programs can execute those functions faster than the server program executes them. In some cases, a user may thus want to suppress supply of those functions from the server program. In such a case, the conventional client server system must delete the functions from the server program and accordingly amend the server program.
For the X window system explained above, there is proposed a technology of using a server program, which is a pseudo X server, between each client program (application program) and the server program (real X server) to which client programs are to be connected to ease the restriction that allows the server program to be connected to each client program at 1:1. (The technology is discussed in Carsten Bormann and Gero Hoffmann's article entitled “Xmc and Xy-Scalable Window Sharing and Mobility or From X Protocol Multiplexing to X Protocol Multicasting”, pp. 205-210, Issue 9, The X Resource.)
This technology demands that each client program should be connected to the pseudo X server instead of the real X server by changing the address given to the client program. In addition, the pseudo X server is connected to the real X server, so that the client program can access the real X server via the pseudo X server. Consequently, this technology changes over the real X server to which the pseudo X server is to be connected so that the client program can request a plurality of real X servers for supply of desired functions. More concretely, the client program can display a window on the display screen of each of the plurality of computers in which a server program (real X server) is executed and display patterns, etc. in the window respectively. This technology, however, is not used to change the protocol (X protocol) for defining data exchanges between each client program and the server program.
In other words, this technology changes over the connection between the pseudo X server and the real X server so that each client program can access a plurality of real X servers and accordingly the restriction for connecting the server program to each client program at 1:1 is eased. The functions supplied to each client program via the pseudo X server are thus completely the same as those supplied by the real X server. Such technology that uses the above pseudo X servers does not take into consideration increasing and reducing functions that can be used by client programs.
SUMMARY OF THE INVENTION
Under such the circumstances, it is an object of the present invention to provide a technology for changing functions that can be supplied to client programs without amending the existing server program.
Particularly, it is an object of the present invention to provide a technology of increasing or reducing functions that can be supplied to client programs without amending the existing server program.
Furthermore, it is an object of the present invention to provide a technology capable of actuating new hardware by conventional software. This technology can dispense with the necessity of fabricating a complicated product including an old interface.
Moreover, it is another object of the present invention to provide a communication technology of increasing or reducing functions that can be supplied to client programs from the server program.
Additionally, it is a further object of the present invention to provide a program, a component or an object equipped with each of the above technologies.
In addition, it is a still further object of the present invention to provide a device in which software equipped with each of the above technologies is installed.
In order to solve the above-mentioned conventional problems, the proxy client server system of the present invention includes a client and a server that notifies the client of entry information for accessing a desired function according to the request from the client and supplies the function corresponding to the address accessed by the client, wherein
the server of the present invention, which is a proxy server that notifies the client of the above entry information instead of the server, further includes
first means of obtaining from the server entry information used for accessing a function that can be supplied from the server to the client;
second means of creating entry information for accessing a function enabled for the client to use, with reference to the obtained entry information; and
third means of notifying the client of the created entry information.
Herein, the server signifies a server program for supplying functions (services) mainly at the request of other units. The client signifies a client program for requesting the server program to supply the functions. Thus, both the client and the server may be actuated inside one and the same information processing unit, or the proxy server may function as both the client and the server.
According to the present invention, a proxy server notifies each client of entry information of usable functions
Higashizono Ryoji
Nakayama Yoshiyuki
Nonaka Naomichi
Hitachi , Ltd.
Kang Paul
Mattingly Stanger & Malur, P.C.
Rinehart Mark H.
LandOfFree
Proxy server and recording medium storing a proxy server... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Proxy server and recording medium storing a proxy server..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Proxy server and recording medium storing a proxy server... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2573089