Publish/subscribe model in a wireless sensor network

• US 20060088014A1
• Filed: 10/27/2004
• Published: 04/27/2006
• Est. Priority Date: 10/27/2004
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Ganesh, Arul
• Granted Patent: US 7,590,098 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor
• CPC Class Codes: H04W 80/10 adapted for application session management, e.g. SIP [Session Initiation Protocol] connection management H04W76/00; arrangements for session management H04L67/14
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A wireless sensor network comprises a plurality of nodes that communicate over wireless communication links. At least one of the plurality of nodes receives sensor data from a sensor. A subscription for an event of interest occurring in the wireless sensor network is installed in the wireless sensor network. A publisher node included in the plurality of nodes determines when the event of interest occurs and, when the event of interest occurs, publishes data related to the event of interest for a subscriber node included in the plurality of nodes.

Claims

1. A wireless sensor network comprising:

a plurality of nodes that communicate over wireless communication links, wherein at least one of the plurality of nodes receives sensor data from a sensor;

wherein a subscription for an event of interest occurring in the wireless sensor network is installed in the wireless sensor network;

wherein a publisher node included in the plurality of nodes determines when the event of interest occurs and, when the event of interest occurs, publishes data related to the event of interest for a subscriber node included in the plurality of nodes.

2. The wireless sensor network of claim 1, wherein each event included in the set of events has an associated event filter for that event that is used by the producer node to identify when that event occurs.

3. The wireless sensor network of claim 1, wherein for at least one event included in the set of events, when that event occurs, the producer node for that event generates the event data related to that event by performing an aggregation operation.

5. The wireless sensor network of claim 1, wherein the sensor data comprises continuous data.

6. The wireless sensor network of claim 5, wherein the publisher node determines when the event of interest occurs based on the continuous data.

7. The wireless sensor network of claim 6, wherein the publisher node uses an event filter to filter the continuous data to determine when the event of interest.

4. The wireless sensor network of claim 4, wherein the aggregation operation comprises calculating at least one of a sum, an average, a minimum, a maximum, and a median.

8. A wireless sensor node, comprising:

a wireless transceiver to communicate over a wireless communication link;

a sensor interface to receive sensor data from a sensor;

wherein when the wireless sensor node receives, from the wireless communication link, a request comprising an event filter associated with an event of interest, the wireless sensor node filters the sensor data in order to determine when the event of interest occurs; and

wherein when the event of interest occurs, the wireless sensor node transmits event data related to the event of interest to a requesting node over the wireless communication link.

9. The wireless sensor node of claim 8, wherein the sensor is included in the wireless sensor node.

10. The wireless sensor node of claim 8, further comprising a programmable processor that executes program instructions that control the operation of the wireless sensor node.

11. The wireless sensor node of claim 8, further comprising a power source.

12. The wireless sensor node of claim 11, wherein the power source comprises a battery.

13. The wireless sensor node of claim 8, wherein the wireless transceiver comprises at least one of a radio frequency transceiver and an infrared transceiver.

14. The wireless sensor node of claim 8, wherein when the event of interest occurs, the wireless sensor node generates the event data related to the event by aggregating at least one of sensor data and data received from another node.

15. The wireless sensor node of claim 8, further comprising a hardware timer.

16. A method of processing a query for data from a wireless sensor network comprising a plurality of nodes that communicate over wireless communication links, at least one of which receives sensor data from a sensor, wherein the query specifies a set of events of interest, at least one of which is related to sensor data sensed by the sensor, the method comprising, for each event included in the set of events of interest:

identifying, at a producer node included in the plurality of nodes, when that event occurs; and

when that event occurs, communicating event data related to that event from the producer node to a consumer node included in the plurality of nodes over a wireless communication link.

17. The method of claim 16, wherein each event included in the set of events of interest has an associated event filter and wherein, for each event included in the set of events of interest, identifying when that event occurs at the producer node for that event comprises filtering at least one of sensor data received by that producer node and event data received from another producer node included in the plurality of nodes.

18. The method of claim 16, further comprising, for each event included in the set of events, selecting the producer node for that event from the plurality of nodes.

19. The method of claim 18, wherein, for each event included in the set of events, selecting the producer node for that event from the plurality of nodes is a function of at least one of power available at at least one of the plurality of nodes, computational resources available at least one of the plurality of nodes, bandwidth available for communicating between the consumer node and at least one of the plurality of nodes, and geographic location of at least one of the plurality of nodes.

20. The method of claim 16, further comprising, for each event included in the set of events, when that event occurs, generating, at the producer node for that event, at least a portion of the event data for that event by aggregating at least one of sensor data received by that producer node and event data received from another producer node included in the plurality of nodes.