Server device, client device, and process execution method

• US 20060069804A1
• Filed: 08/24/2005
• Published: 03/30/2006
• Est. Priority Date: 08/25/2004
• Status: Active Grant

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Inamura, Hiroshi, Nakagawa, Tomohiro, Miyake, Motoharu
• Granted Patent: US 8,001,188 B2
• Time in Patent Office: Days
• US Class Current: 709/237
• CPC Class Codes: H04L 63/1458 Denial of Service

Abstract

A server device 20 requests a client device 30 to execute one of a plurality of computations having different degrees of difficulty. Client device 30 identifies, based on an amount of computation required for each of said plurality of computations, a computation to be executed and executes the computation. Client device 30, when requesting execution of a given process to server device 20, transmits a result of the computation to server device 20. Server device 20, when the computation result is correct, executes a predetermined process according to a priority based on an amount of the computation.

Claims

1. A server device comprising:

transmission means for transmitting to correspondent client devices, a first message including a plurality of client puzzles, each of said plurality of client puzzles including a data set for computation, and said data set for computation for each of said puzzles requiring a different amount of computation, said plurality of client puzzles being transmitted with a request for computation of at least one data set for computation of said puzzles, and with a request for transmission of a solution for said at least one data set for computation;

determination means for determining, when a second message requesting execution of a given process and including a computation result for said at least one data set for computation is received from each of said correspondent client devices, whether a received computation result is correct; and

process execution means for identifying, when said determination means determines that said computation result is correct, an amount of computation carried out by each of said client devices for said at least one data set for computation, and for executing said requested given process prioritized on the basis of the identified computation amount.

2. A server device according to claim 1,

wherein said transmission means transmits said first message in response to a preliminary message requesting only execution of said given process, to a client device being a source of said preliminary message.

3. A server device according to claim 1,

wherein said first message is provided with a predetermined area in which data is contained only when a source and a destination of said first message start a communication, said predetermined area containing appendix data for notifying said destination of detailed modes of the communication;

and

wherein said transmission means transmits said first message including, in said predetermined area, said plurality of client puzzles.

4. A server device according to claim 3,

wherein said transmission means transmits said message according to TCP (Transmission Control Protocol);

and

wherein said predetermined area is Options field.

5. A server device comprising:

communication means; and

control means;

wherein said control means performs;

a first process of transmitting by said communication means to correspondent client devices, a first message including a plurality of client puzzles, each of said plurality of client puzzles including a data set for computation, and said data set for computation for each of said puzzles requiring a different amount of computation, said plurality of client puzzles being transmitted with a request for computation of at least one data set for computation of said puzzles, and with a request for transmission of a solution for said at least one data set for computation;

a second process of determining, when a second message requesting execution of a given process and including a computation result for said at least one data set for computation is received by said communication means from each of said correspondent client devices, whether a received computation result is correct; and

a third process of identifying, when it is determined in said second process that said computation result is correct, an amount of computation carried out by each of said client devices for said at least one data set for computation, and for executing said requested given process prioritized on the basis of the identified computation amount.

6. A client device comprising:

selection means for, when a first message including a plurality of client puzzles, each of said plurality of client puzzles including a data set for computation, and said data set for computation for each of said puzzles requiring a different amount of computation, is received from a correspondent server device with a request for computation of at least one data set for computation of said puzzles, and with a request for transmission of a solution for said at least one data set for computation, selecting a computation to be executed based on an amount of computation, after identifying, based on each said puzzle, a computation amount to be performed for each of said computations;

computation execution means for executing said computation selected by said selection means; and

transmission means for, when requesting said server device to execute a given process, transmitting to said server device a second message with the process execution request, the second message including a computation result obtained by said computation execution means.

7. A client device according to claim 6,

wherein said transmission means, when requesting execution of said given process before receiving said first message, transmits a preliminary message to said server device including only the process execution request.

8. A client device comprising:

communication means; and

control means,

wherein said control means performs;

a first process of, when a first message including a plurality of client puzzles, each of said plurality of client puzzles including a data set for computation, and said data set for computation for each of said puzzles requiring a different amount of computation, is received by said communication means from a correspondent server device with a request for computation of at least one data set for computation of said puzzles, and with a request for transmission of a solution for said at least one data set for computation, selecting a computation to be executed based on an amount of computation, after identifying, based on each said puzzle, a computation amount to be performed for each of said computations;

a second process of executing said computation selected in said first process; and

a third process of, when requesting said server device to execute a given process, transmitting to said server device by said communication means a second message with the process execution request, the second message including a computation result obtained in said second process.

9. A process execution method comprising:

a first step of transmitting from a server device to correspondent client devices, a first message including a plurality of client puzzles, each of said plurality of client puzzles including a data set for computation, and said data set for computation for each of said puzzles requiring a different amount of computation, said first message including a request for computation of at least one data set for computation of said puzzles, and a request for transmission of a solution for said at least one data set for computation;

a second step of selecting, at each client device that has received said first message, a computation to be executed, after identifying, based on each said client puzzle, an amount of computation to be performed for each of said computations, said selection being made based on each identified computation amount, executing the selected computation, and transmitting a second message requesting execution of a given process to said server device, said second message including a result of the executed computation; and

a third process of determining, at said server device upon receipt of said second message, whether said computation result is correct, and, when it is determined to be correct, identifying, based on said computation result, an amount of computation executed by said each client device which is a source of said second message, and for executing said given process according to a priority determined on the basis of the identified computation amount.