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Global Sensor Networks

A Platform for the Internet of Things

Ali Salehi,Prof. Karl Aberer

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What are Sensor Networks ?

ActuatorsSensors

Interconnected!and Actuators,Sensors,

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Properties of existing solutions

ExpensiveTo Modify

Time consuming

HireExpert(s)

People don't benefit from sensor networks.

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Motivation,

?

?

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Question : What is common ?

1. Stream of Data.2. Structure can be defined.3. Common Requirements.

Virtual Sensor

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WHAT DOES ALL THIS MEANWHAT DOES ALL THIS MEAN

Internet of Things.

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Hardware independent, any new hardware (sensors and actuators) should be integratable.

Application independent.

Light & Scalable (internet scale ; peer to peer)

Modifications MUST be very cheap and simple.

Modifications MUST be applied while system is running.

Solution,

Restarting the internet ?!!!

A Software :

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Design, Global Sensor Networks

Common data processing, management and interfacingrequirements, off the shelf.

GSN = implementation of thevirtual sensor concept and theall the listed requirements.

Multi layered architecture to be deployable on resource constrained devices.

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Simplicity, Simplicity, Simplicity (1)Email to MMS

Service (swisscom)

A ) Select Image from CameraB ) Select Temperate from MoteA

Select Camera.Image from A[window 1],B[window 10min]

where avg(temperature) >30

Ap

plicatio

n d

escriptio

n

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Control EngineersAutomatic Control Laboratory ,ETHZ

Requirements: Simplicity, Unified Abstraction.

Matlab Controller

Light &Temperature

Electricblinds

GSN

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Stream Services Develop sensor network applications :

Virtual sensors. Might produce a stream of data (service).

Buy a stream source : Hardware and/or Service (E.g., Lausanne

temperature ).

StreamSources

GSN Virtual Sensors

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Simplicity, Simplicity, Simplicity (2)

Self identifying devices (IEEE 1451).

TEDS and Virtual TEDS.

Zero-programming deployment.

TemplateVirtualSensor

TEDSNew

VirtualSensor

+ =

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High Level View of The GSN

* Uniform API for developing Sensor Network Applications.* Declarative Requirement Management.* Uniform API for exporting sensor data to the GSN. * Various protocols (interfaces) for accessing data.

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Resource Discovery

Addressing the virtual sensors : Static (e.g., socket address).Dynamic using a set of predicates :

Using a Directory Service: <predicate key=“GPS.Latitude”>46.3423</predicate> <predicate key=“Type”>temperature</predicate>

Distributed Directory Service (DDS)*:Based on P-Grid infrastructure.Each node acts as a peer in DDS.

* Not implemented yet.

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Resource Constrained Devices

Resources are allocated on demand.

Resource sharing as much as possible.

20 virtual sensors, 10% > CPU, 64MB RAM, 500 Mhz.

Requirements (e.g., Nokia 770), 32-bit processor. 64 MB Memory and/or Swap Option. 25 MB Storage.

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Wrappers, as of TodayBridge between the sensors/actuators and the GSN.

Wrappers Actuators

TinyOS 1.x SMS Service.

TinyOS 2.x Email Service.

Wise Nodes Pages Service.

TI RFID Readers (20cm)Alien Tech. Readers (20m)

Fax Service.

Wired Cameras EPuck Robots.

Networked Cameras Speaker Output (AT&T)

Generic Bluetooth Protocol

IEEE 1451 Compatibility

Generic Serial

Generic UDP

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Outcome as of today.

Successful Open Source Project.

More than 20 sensors/actuators supported.

7 Releases of the engine (Stable).

30K visitors, 600 downloads.

Users Community GNU GPL License

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WHAT DOES ALL THIS MEANWHAT DOES ALL THIS MEAN

GSN, Middleware for Internet of Things.

Q/A