Sensor network system and data transfer method for sensing data

• US 20060242285A1
• Filed: 01/20/2006
• Published: 10/26/2006
• Est. Priority Date: 03/24/2005
• Status: Active Grant

• Current Assignee: Maxell, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Moriwaki, Norihiko
• Granted Patent: US 7,860,917 B2
• Time in Patent Office: Days
• US Class Current: 709/223
• CPC Class Codes: H04L 67/12 specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

To suppress a server processing load and a network load in a sensor network which accommodates a great number of mobile sensor nodes. Among a plurality of distributed data processing servers (DDS) for managing data of sensor nodes, a distributed data processing server (DDS) that is a home server to hold data of a mobile sensor node is set for each sensor node by a directory server (DRS). At each distributed data processing server (DDS), upon reception of the data from the sensor node, identification process is executed as to whether the data is sensor data to be managed by itself or another distributed data processing server. If a result of the identification is the sensor data to be managed by another distributed data processing server, the data is transferred to the distributed data processing server (DDS-1), which corresponds to the home server of the sensor data, based on setting of the directory server (DRS).

Claims

1. A sensor network system, comprising:

a first distributed processing server and a second distributed processing server which are interconnected through a first network to receive data transmitted from a mobile sensor node, wherein;

when the first distributed processing server receives the data transmitted from the sensor node, the data is held in the first distributed processing server;

when the second distributed processing server receives the data transmitted from the sensor node, the second distributed processing server transfers the data; and

the first distributed processing server holds the data transferred from the second distributed processing server.

2. The sensor network system according to claim 1, further comprising a management server connected to the first distributed processing server and the second distributed processing server through the first network, wherein:

the management server comprises a system manager which assigns the first distributed processing server to hold the data transmitted from the sensor node;

each of the first distributed processing server and the second distributed processing server comprises a judging module which judges holding or transferring of the data transmitted from the sensor node based on the system manager; and

the management server receives the data transferred from the second distributed processing server, and transfers the received data to the first distributed processing server.

3. The sensor network system according to claim 1, further comprising a management server connected to the first distributed processing server and the second distributed processing server through the first network, wherein:

the management server comprises a system manager which assigns the first distributed processing server to hold the data transmitted from the sensor node; and

each of the first distributed processing server and the second distributed processing server comprises a judging module which judges holding or transferring of the data transmitted from the sensor node based on the system manager, and an executer which holds or transfers the data transmitted from the sensor node based on a judgment result of the judging module.

4. The sensor network system according to claim 2, wherein:

the sensor node transmits data including an identifier for identifying the data to the first distributed processing server or the second distributed processing server;

the management server manages the identifier and a location of the first distributed processing server for holding the data including the identifier in association with each other in the system manager,

each of the first and second distributed processing servers comprises an extractor which extracts the identifier from the received data, and a list which holds identifiers and preset processes corresponding to the identifier; and

the second distributed processing server transfers the data to the management server when the list does not hold the identifier.

5. The sensor network system according to claim 4, wherein the management server further comprises an action table which holds an identifier managed by the system manager and the location of the first distributed processing server for holding data including the identifier in association with each other, and transfers the data to the first distributed processing server based on the action table when the data is transferred from the second distributed processing server.

6. The sensor network system according to claim 5, wherein in a case where the identifier included in the data is not held in the action table when the data is transferred from the second distributed processing server, the management server instructs the action table to holds the identifier managed by the system manager and the location of the first distributed processing server for holding the data including the identifier based on a transferred identifier.

7. The sensor network system according to claim 3, wherein:

the sensor node transmits data including an identifier for identifying the data to the first distributed processing server or the second distributed processing server;

the management server manages the identifier and the first distributed processing server for holding the data including the identifier in association with each other by the system manager;

each of the first and second distributed processing servers comprises an extractor which extracts the identifier from the received data, and a list which holds the identifiers and preset processes to be held corresponding to the identifier; and

when the process corresponding to the identifier is a process of transferring data to the first distributed processing server, the second distributed processing server transfers the data including the identifier to the first distributed processing server upon reception of the data including the identifier from the sensor node.

8. The sensor network system according to claim 7, wherein:

in a case where the identifier included in the data is not held in the list upon reception of the data from the sensor node, the second distributed processing server makes an inquiry to the management server based on a received identifier;

the management server transmits the identifier managed by the system manager and a location of the first distributed processing server for holding the data including the identifier; and

the second distributed processing server holds in the list the identifier and the location of the first distributed processing server for holding the data including the identifier.

9. The sensor network system according to claim 8, wherein the second distributed processing server sets discarding of the received data including the identifier if the received identifier is not managed by the system manager.

10. The sensor network system according to claim 8, wherein the second distributed processing server holds in the list the identifier and the location of the first distributed processing server for holding the data including the identifier based on the inquiry to the management server, and deletes the identifier and the location of the first distributed processing server for holding the data including the identifier from the list when the data is not received from the sensor node for a predetermined time.

11. The sensor network system according to claim 1, wherein one of the first distributed processing server and the second distributed processing server receives the data including position information indicating a position of the sensor node.

12. The sensor network system according to claim 11, further comprising a first base station connected to the first distributed processing server and a second base station connected to the second distributed processing server, wherein:

the first distributed processing server receives the data transmitted from the sensor node through the first base station;

the second distributed processing server receives the data transmitted from the sensor node through the second base station; and

each of the first base station and the second base station adds one of an identifier or an address of the base station itself as the position information to the data received from the sensor node.

13. The sensor network system according to claim 11, further comprising a first base station connected to the first distributed processing server and a second base station connected to the second distributed processing server, wherein:

the first distributed processing server receives the data transmitted from the sensor node through the first base station;

the second distributed processing server receives the data transmitted from the sensor node through the second base station; and

each of the first base station and the second base station adds one of an identifier and an address of the base station itself as the position information to the data received from the sensor node.

14. The sensor network system according to claim 12, wherein:

the management server transmits a command to be sent to the sensor node to the first distributed processing server; and

the first distributed processing server transmits the command to the base station which receives the data transmitted from the sensor node based on the received position information indicating the position of the sensor node.

15. A machine-readable medium embodying a program for causing a distributed processing server to receive data from a sensor node and to perform one of transferring the data and holding the data, wherein the program causes the distributed processing server to execute:

a process of receiving the data from the sensor node;

a process of judging a holding place of the data;

a process of transferring the data when the holding place is another distributed processing server;

a process of receiving data from a management server and another distributed processing server; and

a process of holding data in one of cases where the data is received from the management server and another distributed processing server, and where the holding place of the data is the distributed processing server.

16. The machine-readable medium embodying the program according to claim 15, wherein:

the process of judging the holding place of the data includes a process of making an inquiry about the holding place of the received data to the management server, and a process of judging whether the inquired holding place is another distributed processing server or the distributed processing server; and

the process of transferring the data transfers the received data to the management server.

17. The machine-readable medium embodying the program according to claim 15, wherein:

the process of judging the holding place of the data includes a process of making an inquiry about the holding place of the received data to the management server, and a process of judging whether the inquired holding place is another distributed processing server or the distributed processing server; and

the process of transferring the data transfers the received data to another distributed processing server based on a result of the inquiry.

18. The machine-readable medium embodying the program according to claim 16, wherein:

the process of receiving the data from the sensor node includes a process of extracting a data identifier from the received data;

the process of making the inquiry to the holding place makes an inquiry about the holding place of the received data to the management server based on the identifier;

the process of judging the holding place of the data includes a process of holding the identifier and a preset process corresponding to the identifier in a list; and

the process of judging the holding place judges that the holding place is the distributed processing server if the identifier is in the list, and that the holding place is another distributed processing server if the identifier is not in the list.

19. The machine-readable medium embodying the program according to claim 17, wherein:

the process of receiving the data from the sensor node includes a process of extracting a data identifier from the received data;

the process of judging the holding place of the data includes a process of holding the identifier and a preset process corresponding to the identifier in a list, and judgment is made as to whether the holding place of the data is the distributed processing server or another distributed processing server from the list based on the identifier; and

the process of transferring the data transfers the data including the identifier to another distributed processing server corresponding to the identifier.

20. The machine-readable medium embodying the program according to claim 17, wherein:

the process of receiving the data from the sensor node includes a process of extracting a data identifier from the received data;

the process of making the inquiry to the holding place makes an inquiry about the holding place of the received data to the management server based on the identifier;

the process of judging the holding place of the data includes a process of holding the identifier and a holding place corresponding to the identifier in a list, and judgment is made as to whether the holding place of the data is the distributed processing server or another distributed processing server by obtaining a holding place of data from the list based on the identifier; and

the process of transferring the data transfers the data including the identifier to another distributed processing server of the holding place.

21. The machine-readable medium embodying the program according to claim 20, wherein when the holding place of the data is not obtained from the list based on the identifier, the process of judging the holding place of the data discards the received data.

22. The machine-readable medium embodying the program according to claim 20, further comprising a process of deleting the identifier and the holding place from the list when the data including the identifier indicating that the holding place is another distributed processing server is not received for over a predetermined time period.

23. The machine-readable medium embodying the program according to claim 15, wherein the process of receiving the data from the sensor node receives the data including position information of the sensor node.

24. The machine-readable medium embodying the program according to claim 23, wherein the process of receiving the data from the sensor node receives data including an identifier or an address of a base station which relays the data of the sensor node, and

the process of transferring the data transfers the data including a data identifier and one of the identifier and the address of the base station.

25. The machine-readable medium embodying the program according to claim 24, wherein:

the process of receiving the data from the management server and another distributed processing server receives a command including position information of the base station from the management server; and

the process of transferring the data transfers data including the command to the base station corresponding to the identifier.

26. A machine-readable medium embodying a program for causing a management server to receive data from a distributed processing server and to transfer the data to another distributed processing server, wherein the program causing the management server to execute:

a process of receiving data from the distributed processing server;

a process of retrieving a holding place of the data; and

a process of transferring the data to the holding place.

27. The machine-readable medium embodying a program according to claim 26, wherein:

the process of receiving the data from the distributed processing server includes a process of extracting a data identifier from the received data;

the process of judging searches in an action table including the identifier and a preset holding place corresponding to the identifier to judge a holding place of the data; and

the process of transferring the data transfers the data to the holding place retrieved from the action table.

28. The machine-readable medium embodying the program according to claim 27, wherein the process of judging obtains the holding place corresponding to the identifier from a preset sensor node information table when the identifier is not in the action table, and holds the identifier and the holding place corresponding to the identifier in the action table.

29. The machine-readable medium embodying the program according to claim 28, wherein the process of judging discards the received data when the holding place corresponding to the identifier is not in the sensor node information table.