1. Sensor Networks UCE BURLA

2. 11/19/2015Presentation on Sensor Networks2 Technical Terms SINA – Software Information Network Architecture. Beacons. TinyOS – Tiny Micro-threading Operating System. SPIN – Sensor Protocols for Information via Navigation.

3. 11/19/2015Presentation on Sensor Networks3Contents Introduction Overview of Architecture and Operating System Energy Efficient methods Localization Routing Applications (Some systems which make use of sensor networks) Sensor Network simulators Conclusion

4. 11/19/2015Presentation on Sensor Networks4 Introduction Definition: – Sensor networks are dense wireless networks of small, low-cost sensors, which collect and disseminate environmental data. – Used for monitoring and controlling of physical environments from remote locations with better accuracy.

5. 11/19/2015Presentation on Sensor Networks5 Introduction (Cont…) Earlier sensor networks… Now, sensor networks… Why distributed, wireless sensing??? – Closer placement. Depends upon: – Dense Deployment. – Co-ordination among the nodes.

6. 11/19/2015Presentation on Sensor Networks6 Features Local Processing. Wireless Communication. Complete system on Chip. Integrated Low-power communication. Integrated Low-power transducers.

7. 11/19/2015Presentation on Sensor Networks7 Focus Is On… Energy and computational constraints. – Energy Efficiency. – Localization algorithms. – Routing.

8. 11/19/2015Presentation on Sensor Networks8 2. Architecture Characteristics: – Small physical size and low power consumption. – Concurrency intensive operation. – Limited physical parallelism and controller hierarchy. – Diversity in design and usage. – Robust Operation. Sensor Information Networking Architecture – A middle ware. – Issue queries and command tasks into. – Collects replies and results from. – Monitor changes. Hierarchical Clustering. Attribute-based naming. Location Awareness.

9. 11/19/2015Presentation on Sensor Networks9 2. Architecture (Cont…) Data sheets. Sensor Query and Tasking Language (SQTL). – Interface between sensor application and SINA middleware. – getTemperature, turnON, isNeighbor, getPosition, tell, execute, etc. – Event handling: Receive, every, expire. – Software Execution Engine ( ALL, NEIGHBORS, etc )

10. 11/19/2015Presentation on Sensor Networks10 Information Gathering Sampling Operation (Adaptive Probability Response). Self-Orchestrated Operation. Diffused Computation Operation. Internetworking between a Mobile User and Stationary Network. – Tracking the mobile User. – Progressive footprint chaining.

11. 11/19/2015Presentation on Sensor Networks11 2. Architecture (Cont…) Hardware Organization. – Processor and co-processor. – Provide interfaces to sensing devices (light, temperature, etc). – Designed to work in three different modes (idle, power down, power save). – Three leads available. – Power Characteristics. Why an OS? – Requirement of an OS which can perform the tasks. – Effective usage of hardware. – Support concurrent-intensive operation. – Unused CPU cycles are spent in sleep mode. – Achieve robustness.

12. 11/19/2015Presentation on Sensor Networks12 2. Architecture (Cont…) TinyOS design. – Event modeling. – A stack based threaded approach. – Two level scheduling. – Components. Set of command handlers. Set of event handlers. An encapsulated fixed size frames. Bundle of simple tasks.

13. 11/19/2015Presentation on Sensor Networks13 Figure 1: http://citeseer.ist.psu.edu/382595.html

14. 11/19/2015Presentation on Sensor Networks14

15. 11/19/2015Presentation on Sensor Networks15 3. Energy Efficiency Computing Subsystem. – microprocessor. Communication subsystem. – radio. Sensing subsystem – sensors and actuators. Power Supply – con sists of a battery. Solution. – Develop methodologies which are energy aware. – Distribution of traffic. – Residual Energy Scan (eScan) – by Younggang Zaho.

16. 11/19/2015Presentation on Sensor Networks16 4. Localization Nodes are in general deployed into an unplanned infrastructure (no priori knowledge). Problem of estimating the spatial co-ordinates is referred to as Localization (generally done by trilateration). Initial high-level nodes (beacons) broadcasts their address. (Proximity based Localization). Multilateration (iterative process).

17. 11/19/2015Presentation on Sensor Networks17 Trilateration/multilateration A AB AB C

18. 11/19/2015Presentation on Sensor Networks18 4. Localization (Cont…) Fine – grained. – Timing. – Signal Strengths. – Signal Pattern Matching. Pre-scanning takes place. A central system assigns a unique signature to each square in the location grid. Coarse – grained. – Proximity based Localization. Nodes should adopt themselves to avoid to available reference points. – Connectivity metric=(tot. no. of signals received)/(tot. no. of signals sent). – Node’s position is calculated by centroid of all reference points.

19. 11/19/2015Presentation on Sensor Networks19 Suggested Alg. For Beacons Random Max Grid Heap (Selective Turning off BEacons)

20. 11/19/2015Presentation on Sensor Networks20 5. Routing Implosion Ad-hoc protocols – Proactive – static: maintains a routing table. – Reactive – dynamic: establishes when required. Negotiation based protocols SPIN (meta-data) : uses ADV, REQ and DATA. – SPIN – PP (point-to-point) – SPIN – EC (energy conservative) – SPIN – BC (broadcast) – SPIN – RL

21. 11/19/2015Presentation on Sensor Networks21 5. Routing (Cont…) Directed diffusion. – Attribute-value pairs are maintained. – Sink. – Interest cache. – Fields. Timestamp. Gradient – data rate. Duration – lifetime. Energy Aware Routing. – Destination initiative reactive protocol. – Multiple good optimal paths are maintained.

22. 11/19/2015Presentation on Sensor Networks22 6. Applications Active Badge Location System. Pin-point 3D-iD local positioning system. Intelligence department. Environmental monitoring. Military purposes. Gathering sensing information in inhospitable locations.

23. 11/19/2015Presentation on Sensor Networks23 7. Sensor Network Simulator NS –2 ; written in c++ and oTCL. GloMoSim (Global Mobile Information System Simulator); written in C and parsec. SensorSim;

24. 11/19/2015Presentation on Sensor Networks24 Challenges Ad hoc deployment Unattended Operation Untethered (Limited Energy resource) Dynamic Changes Ultimate Struggle System Lifetime System robustness

25. 11/19/2015Presentation on Sensor Networks25 Conclusion Promising applications Evolving field Scope for lots of research

26. 11/19/2015Presentation on Sensor Networks26References http://wwwcsif.cs.ucdavis.edu/~bharathi/sensor/survey.pdf http://ieeexplore.ieee.org/iel5/45/26953/01197877.pdf http://ieeexplore.ieee.org/iel5/98/20430/00944004.pdf http://citeseer.ist.psu.edu/382595.html http://www.research.rutgers.edu/~mini/sensornetworks.html http://www2.parc.com/spl/members/zhao/stanford-cs428/ http://www.eng.auburn.edu/users/lim/sensit.html http://geometry.stanford.edu/member/guibas/ http://pdos.csail.mit.edu/span/ http://www.tinyos.net/ http://bit.csc.lsu.edu/news/faculty-candidate.html http://www.janet.ucla.edu/WINS/ http://www.cs.duke.edu/~alvy/courses/sensors/Papers.html

27. 11/19/2015Presentation on Sensor Networks27 Thank You