Towards a Web of Sensors built with Linked Data and REST

Transcription

1 Towards a Web of Sensors built with Linked Data and REST S. Turchi, L. Bianchi, F. Paganelli, F. Pirri, D. Giuli, Towards a web of sensors built with linked data and REST, 2013 IEEE 14th International Symposium on a World of Wireless, Mobile and Multimedia Networks, WoWMoM 2013, art. no , Madrid, Spain, 4-7 June 2013, /WoWMoM

2 References S. Turchi, L. Bianchi, F. Paganelli, F. Pirri, D. Giuli, Towards a Web of Sensors built with Linked Data and REST, 2nd IEEE WoWMoM Workshop on the Internet of Things: Smart Objects and Services (IoT-SoS 2013, colocated with 14th IEEE Int. Symp. on a World of Wireless, Mobile and Multimedia Networks (WoWMoM 2013), Madrid, Spain 4-7 June. F. Paganelli, S. Turchi, L. Bianchi, L. Ciofi, M.C. Pettenati, F. Pirri, and D. Giuli, "An information-centric and REST-based approach for EPC Information Services, Journal of Communications Software and Systems, vol. 9, no. 1, March

3 Outline Context and Motivation Our approach towards a Web of Sensors Information-centric model Web APIs Middleware services Ongoing experiment within the SmartSantander EU project Conclusions 3

4 Context Web of Things Ease the end-user interaction with sensors and smart objects by leveraging the Web Functionalities for publishing the sensors representation and make them accessible on the Web 4

5 Motivation State of the art in the Web of Things/Web of Sensors (WoS): SensorWeb OGC specifications Several research and implementation proposals Web APIs (REST) Semantic annotations and links (Linked Data) Current limitation Poor support to the development of web applications in the WoS A limitation to access, reuse and compose sensor data i.e. the WoS objective! 5

6 Our Proposal A graph-based representation of sensors Original combination of REST and Linked Data principles WoT as a browsable graph of resource nodes Uniform Web Interface Creation and Execution environment Middleware implementing discovery, search, brokering capabilities Design tools (GUI and JavaScript libraries) 6

7 Why REST and Linked Data? Leverage the Web s grounding principles and best practices REST What it is Architectural style Uniform Interface (HTTP verbs) It is based on the principles that make the web scalable Useful for Lowering entry barriers for web developers Offering lightweight and uniform API for accessing data Linked Data A set of best practices for publishing and connecting data and their semantics on the Web Standard technologies (HTTP, RDF, XML, ) Global browsable information space, interlinking data coming from different information sources Shared representation of interlinked data REST and Linked Data complement each other! 7

8 IDN Information Model Node: an information element, made by data (content) and metadata URI-addressable Relations Aggregation Reference Document: a collection of IDN Nodes (1..n) exposed as a web resource Uniform REST interface../../{nodeid} /{nodeid} 1 1 attribute attribute../{nodeid} aggregation link reference link attribute1 attribute2 attributen../ /{nodeid} attribute../{nodeid} 8

9 Sensor Information Model Sensor object representation GET URI information retrieval PUT creation/update DELETE deletion Different design choices are allowed!../location sensor/{nodeid} 1 1 longitude latitude nodeid type battery../data_production 1..n date aggregation link../{physical_quantity} value measurement_unit 9

10 Exploiting the Model - 1 Virtual sensor software-based sensor whose value derives from physical sensor ones Advantages: Geographical coverage New sensor type 10

11 Exploiting the Model 2 Interlinking sensor information more complex graphs can be built 11

12 IDN Studio IDN Search SmartSantander Kick Off Meeting InterDataNet Architecture IDN Service Platform Information-centric REST APIs IDN Adapter Sensing Infrastructures Information repositories REST and Web Services 12

13 IDN Studio IDN Search SmartSantander Kick Off Meeting Experiment in SmartSantander Users Web Applications Information-centric REST APIs IDN Service Platform IDN Adapter 13

14 Apparent Temp. (AT) Web App VSs for AT in locations like schools, public gardens, hospitals AT = + Benefits End users Quality of Life Alerts Developers Fast development process Reduced programming skills 14

15 Conclusions Approach for easing the building of a Web of Sensors Connection to sensors and existing sensor middleware through a dedicated adapter Representation of objects through a graph of URI-addressable data units Thanks to the adoption of REST and Linked Data principles Interoperability and scalability Tools easing the development of web of sensors applications Ongoing work Experiment in SmartSantander Semantic-enabled search capabilities Security Framework 15

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