Publishing LO(D)D: Linked Open (Dynamic) Data for Smart sensing and Measuring environments

Transcription

1 Politecnico di Torino Dip. Automatica e Informatica The 3rd International Conference on Ambient Systems, Networks and Technologies August 27-29, 2012, Niagara alls, Ontario, Canada Torino, Italy Publishing : Linked Open (Dynamic) Data for Smart sensing and Measuring environments ulvio Corno, aisal Razzak

2 oals nable sensor networks to publish their data in a standard way nable distributed applications to consume sensor data from different sources nable data publication, consumption, computation, republication, etc with minimal effort xtend the Linked Open Data cloud with time-varying (sensor) data streams 2

3 Outline Context and Motivation Proposed Architecture Proposed solutions xperimental results Conclusions 3

4 Context Smart Homes Smart Sensing and Measuring nvironments Smart rid Social mobile applications Sensor and Actuator Networks Smart actories nvironment monitoring Smart Appliances Affordable and efficient sensors 4

5 Context Smart Sensing and Measuring nvironments energy (active, reactive, reverse, kvar,...) Smart Appliances acceleration compass air pressure temperature light acceleration compass PS proximity microphone camera BT Scan Affordable and efficient sensors 5

6 Context Smart Sensing and Measuring nvironments Smart Appliances Affordable and efficient sensors Motion Smoke yroscope RID Pressure Proximity 2D codes 6

7 Motivation Application nviron ment Applian ces sensors nviron ment Applian ces sensors Application nviron ment Applian ces sensors Applications need to access information from multiple environments Standard way to publish and consume information About accessible environments About available applicances, sensors and their characteristics About the actual data measured by sensors 7

8 Approach Adopt Semantic Web «Linked Open Data (LOD)» approach Static information: Can be encoded in RD according to a public Ontology Dynamic information: New approach to represent streams of RD events Applications need to access information from multiple environments Standard way to publish and consume information About accessible environments About available applicances, sensors and their characteristics About the actual data measured by sensors 8

9 eneral Architecture Smart nvironment Producer Application publishes Static information about sensor streams monitors 9

10 eneral Architecture Smart nvironment monitors Producer Application publishes describes Static information about sensor streams updates Sensor data channel Sensor data channel Sensor data channel 10

11 eneral Architecture Smart nvironment monitors Producer Application updates publishes describes Static information about sensor streams Sensor data channel Sensor data channel Sensor data channel subscribes receives Consumer Application Consumer Application Consumer Application 11

12 Proposed solutions Producer Application Consumer Application Static information about sensor streams Sensor data channel Open source libraries and API to enable application to interact with data RD document with meta-data (PID) Publisher information List of channels, their source data, their datatypes, and subscription URI/key RD «fragments» representing each event Contains: event#, sensor id, timestamp, value, unit of measure Uses publish-subscribe pattern as transport mechanism for distributing RD fragments 12

13 Publisher Information Document (PID) According to lightweight «Publisher» ontology Contains declarations of all channels handled by this publisher all needed static information ives information to subscribe to channels Created by publisher API Published over http <RD:Description RD:about="&Publisher;energymtr"> <publisher:location RD:datatype="&xsd;string"> Torino, Italia</publisher:Location> <publisher:subscribekey>sub-xxxxxx-42904d46d </publisher:subscribekey> <publisher:channelname>nergy Meters </publisher:channelname> <RD:type RD:resource="&Publisher;Channel"/> </RD:Description> 13

14 vent data fragments Indivudual data points encoded in RD Self-consistent information (e.g. Unit of measure) Standard syntax and semantics Application-independent representation Compact encodings available <rdf:description RD:about = "&publisher;emergymtrchan1"> <publisher:meternumber RD:datatype="&xsd;int"> 231 </publisher:meternumber> <publisher:unit RD:datatype="&xsd;string" > bel-kilowatt</publisher:unit> <publisher:hastimestamp RD:datatype="&xsd;dateTime"> T13:06:41.056Z </publisher:hastimestamp> 14 <publisher:hascurrentvalue RD:datatype ="&xsd;double"> 0.3 </publisher:hascurrentvalue> </RD:Description>

15 Cloud based Transport mechanism Provides the updates to subscribers whenever publishers update data New RD fragments are sent to the cloud service Maintains list of subscribers Handles logic to provide transport from Publisher to many Subscriber in real time It makes the Publisher a light-weight component Publisher is independent from the number of connected subscribers pubsubhubbub...and others 15

16 Publisher and Consumer APIs Publisher Library Creates PID file an offers it on http Creates channels onto cloud service Sends updates to channel, encoding it in RD Consumer Library Parses PID file and provides channel information Subscribes to one or more channels Notifies application whenr new data is available, decoding it from RD Same application may be producer and consumer at the same time Applications need not manage RD explicitly 16

17 Preliminary xperiment Building Infrastructure Politecnico di Torino Publishes polinergy PID P 126 lectrical Meters. Take reading every 15 minutes 17

18 Preliminary xperiment Building Infrastructure Politecnico di Torino Publishes polinergy PID C P P 126 lectrical Meters. Take reading every 15 minutes polinergy Aggregator PID Aggregates reading into 3 ranges. Publishes using 3 channels 18

19 Preliminary xperiment Building Infrastructure Politecnico di Torino Publishes polinergy PID C P P 126 lectrical Meters. Take reading every 15 minutes polinergy Aggregator PID 19 C Aggregates reading into 3 ranges. Publishes using 3 channels

20 Conclusions Open applications with open data xploiting existing standards (RD and pub/sub) xtensible to different type of sensor data Highly scalable 20

21 21