Information processing system and method for same

• US 20030144975A1
• Filed: 01/13/2003
• Published: 07/31/2003
• Est. Priority Date: 05/06/1998
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Kawamura, Takahiro, Ohsuga, Akihiko, Hasegawa, Tetsuo, Tahara, Yasuyuki, Kase, Naoki
• Granted Patent: US 7,016,934 B2
• Time in Patent Office: Days
• US Class Current: 706/45
• CPC Class Codes: G06F 9/4875 with migration policy, e.g. auction, contract negotiation
• CPC Class Codes: G06N 5/01 Dynamic search techniques; Heuristics; Dynamic trees; Branch-and-bound
• CPC Class Codes: G06N 5/043 Distributed expert systems; Blackboards
• CPC Class Codes: H04L 67/10 in which an application is distributed across nodes in the network software deployment G06F8/60; multiprogramming arrangements G06F9/46
• CPC Class Codes: H04L 67/34 involving the movement of software or configuration parameters network booting or remote initial program loading [RIPL] G06F9/4416
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A mobile agent mediates cooperation among schedulers by executing a cooperation protocol. For heuristics such as strategies and the order in which variables are decided, which are used as criteria of selecting the value of a variable from candidates, when the heuristics are to be built into a solving method of a constraint satisfaction problem, processes with regard to these heuristics are so substantially localized as to be capable of parallel execution. These processes capable of parallel execution, as autonomous operations of different mobile agents, can be under modeling in natural form, resulting in easy installation. This facilitates software construction for reflecting the heuristics in a solving method of a constraint satisfaction problem, as well as improves the maintainability and extendibility of software.

Claims

1. A processing unit among a plurality of processing units that form a distributed system, comprising:

storage means for storing target knowledge with regard to a given target and problem solving knowledge representing how problem solving with regard to said target is to be performed;

communication means for communicating with a mediation agent to transmit information of the processing unit and receive information from the mediation agent; and

processing means for performing a part of said problem solving by making use of said target knowledge and said problem solving knowledge fundamentally and making use of said information from said mediation agent optionally,

wherein said mediation agent is generated when the processing unit is required to cooperate with another processing unit, wherein the mediation agent migrates among said processing units and has cooperation problem solving knowledge that represents how said processing units cooperate with each other to perform said problem solving, and wherein the mediation agent mediates cooperation among said units by making use of said cooperation problem solving knowledge to cause said each unit to perform said problem solving.

2. The processing unit according to claim 1, wherein the processing unit is a scheduler that has a plurality of variables and performs a constraint satisfaction problem solving by assigning for each variable a value that is not contrary to a constraint among the variables.

3. The processing unit according to claim 1, wherein said communication means communicates with said mediation agent in a predetermined format.

4. The processing unit according to claim 3, wherein said medication agent comprises:

communication means for communicating with said each processing unit in said format; and

coordination means for performing coordination among said processing units.

5. The processing unit according to claim 3, wherein said each processing unit exists on a plurality of nodes, respectively, and wherein said mediation agent has the mobility to migrate among said nodes.

6. The processing unit according to claim 4, wherein the processing unit comprises coordination means for performing coordination of the processing unit.

7. The processing unit according to claim 4, wherein said coordination means of said mediation agent comprises:

protocol management means for managing an interaction protocol that performs coordination among said processing unit; and

status management means for performing said coordination by managing status of information processing based on said interaction protocol.

8. The processing unit according to claim 1, wherein said mediation agent comprises means for diminishing the mediation agent when the mediation agent completes cooperation among said processing units.

9. A mobile agent which migrates among a plurality of processing units that form a distributed system, comprising;

storage means for storing cooperation problem solving knowledge that represents how said plurality of processing units cooperate with each other to perform said problem solving;

communication means for communicating with said plurality of processing units to receive information from each processing unit and transmit information generated from either or both of said cooperation problem solving knowledge and the received information to each processing unit; and

processing means for generating the information to be transmitted to each processing unit by making use of said cooperation problem solving knowledge when said plurality of processing units are required to cooperate with each other, and for mediating cooperation among said processing units by causing said communication means to transmit the generated information to each processing unit, whereby causing each processing unit to perform said problem solving.

10. The mobile agent according to claim 9, wherein said each processing unit is a scheduler that has a plurality of variables and performs a constraint satisfaction problem solving by assigning for each variable a value that is not contrary to a constraint among the variables, wherein said mobile agent comprises generation means for generating an agent in correspondence to each alternative when there exists a plurality of alternatives with regard to the assignment of values for the variables, and wherein said each agent corresponding to each alternative executes said cooperation protocol among said schedulers independently of the other agents and according to the alternative.

11. The mobile agent according to claim 9, wherein said each processing unit is a scheduler that has a plurality of variables and performs a constraint satisfaction problem solving by assigning for each variable a value that is not contrary to a constraint among the variables, wherein said mobile agent comprises generation means for generating an agent in correspondence to each strategy if there exists a plurality of strategies of what criterion is used for selection of a value to be assigned, and wherein said each agent corresponding to each strategy performs search of said solution by assigning values for the valuables independently of the other agents, at the same time, and according to the strategy.

12. The mobile agent according to claim 9, wherein said each processing unit is a scheduler that has a plurality of variables and performs a constraint satisfaction problem solving by assigning for each variable a value that is not contrary to a constraint among the variables, wherein said mobile agent comprises generation means for generating an agent in correspondence to each variable when there are a plurality of schedulers that have variables being approximately equal in priority with regard to the order in which values are decided, wherein said each agent corresponding to each variable performs search of said solution by assigning values for the valuables independently of the other agents and at the same time, and wherein said mobile agent comprises means for merging each agent by changing each variable so as to minimize the change of each variable according to said constraint among the variables.

13. The mobile agent according to claim 9, wherein said each processing unit comprises communication means for communicating with said mobile agent in a predetermined format.

14. The mobile agent according to claim 13, wherein the mobile agent comprises:

communication means for communicating with said each processing unit in said format; and

coordination means for performing coordination among said processing units.

15. The mobile agent according to claim 13, wherein said each processing unit exists on a plurality of nodes, respectively, and wherein the mobile agent has the mobility to migrate among said nodes.

16. The mobile agent according to claim 14, wherein at least one of said processing units comprises coordination means for performing coordination of the processing unit.

17. The mobile agent according to claim 14, wherein said coordination means of the mobile agent comprises:

protocol management means for managing an interaction protocol that performs coordination among said processing units; and

status management means for performing said coordination by managing status of information processing based on said interaction protocol.

18. The mobile agent according to claim 9, wherein the mobile agent comprises means for diminishing the mobile agent when the mobile agent completes cooperation among said processing units.