1. OVERVIEW OF WIRELESS SENSOR NETWORKS: Key definitions of sensor networks. Advantages of sensor Networks. Unique constraints an challenges. Driving Applications. Enabling Technologies for Wireless Sensor Networks.

2. Key Definitions of Sensor Networks: Key Definitions of Sensor Networks: Sensor Sensor node Network topology Routing Date-centric Geographic routing Collaborative processing In-network

3. Uncertainty State Task Detection Classification Value of information or information utility. Resource Sensor tasking

4. Embedded operating system (OS) Evaluation metric Node services Data storage

5. Advantages of Sensor Networks: Energy Advantage: P send ∝ r α P receive

6. Detection Advantage SNR r = 10 log Where as SNR r = 10 log P source − 10 log P noise − 20 log r. Increasing the sensor density by a factor of k, reduces the average distance to a target by a factor of Increase in sensor density by a factor of k improves the SNR at a sensor by 10 log k db.

7. Applications of wireless sensor networks: Military applications Monitoring inimical forces Monitoring friendly forces and equipment Military-theater or battlefield surveillance Targeting Battle damage assessment Nuclear, biological, and chemical attack detection and more...

8. Environmental applications Microclimates Forest fire detection Flood detection Precision agriculture and more... Health applications Remote monitoring of physiological data Tracking and monitoring doctors and patients inside a hospital Drug administration Elderly assistance and more...

9. Home applications Home automation Instrumented environment Automated meter reading and more... Commercial applications Environmental control in industrial and office buildings Inventory control Vehicle tracking and detection Traffic flow surveillance and more... Disaster relief applications Precision agriculture

10. Enabling Technologies for Wireless Sensor Networks: Hardware: Wireless Networking: Collaborative Signal Processing: Energy scavenging:

11. Challenges for WSNs 1.Characteristic requirements 2.Required mechanisms 1.Characteristic requirements: Type of service Quality of Service Fault tolerance Lifetime Scalability Wide range of densities Programmability Maintainability

12. 2. Required mechanisms Multihop wireless communication Energy-efficient operation Auto-configuration Collaboration and in-network processing. Data centric Locality Exploit trade-offs

13. ARCHITECTURES: Single-Node Architecture – Hardware Components Energy Consumption of Sensor Nodes Operating Systems and Execution Environments, Network Architecture – Sensor Network Scenarios Optimization Goals and Figures of Merit Gateway Concepts.

14. Hardware Components Controller. Memory. Sensor and actuators. Communication. Power supply.

15. Overview of main sensor node hardware components

16. Transceiver operational states

17. Sensors & Actuators Sensors in WSN are used to capture the environmental variables and which is used for data acquisition. Sensor signals are converted into electrical signals. Actuator is a device that converts the electrical signals into the physical events or characteristics. It takes the input from the system and gives output to the environment.

18. Energy Consumption of Sensor Nodes 1. Operation states with different power consumption. 2. Microcontroller energy consumption. 3. Memory. 4. Radio transceivers.

19. Operation states with different power consumption:

20. E overhead = t up (P active + P sleep )/2. Esaved =(tevent − t1)Pactive − ( τ down(Pactive + Psleep)/2 + (tevent − t1 − τ down)Psleep). E active = P active (t event − t 1 ).

21. Operating Systems and Execution Environments: An operating system (OS) is system software that manages computer hardware and software resources and provides services

22. Tiny OS 1. It is an open-source 2. flexible 3. application-specific operating system for wireless sensor networks.

23. Salient features of Tiny OS 1. simple event-based concurrency model 2. It has a component-based architecture 3. Tiny OS’s component library includes network protocols, distributed services, sensor drivers, and data acquisition tools. 4. Tiny OS’s event-driven execution model

24. common services for computer programs. 1. Embedded operating systems: 2. Programming paradigms:  Concurrent Programming (sequential program model).  Process-based program model  Event-based programming model

25. Sequential programming modelProcess-based programming model Event-based programming model

26. Network Architecture – Sensor Network Scenarios Optimization Goals and Figures of Merit Gateway Concepts. Sensor Network Scenarios: 1.Types of sources and sinks. 2.Single-hop versus multihop networks. 3.Multiple sinks and sources. 4. Three types of mobility.

27. 2.Single-hop versus multihop networks.

28. 3.Multiple sinks and sources

29. 4. Three types of mobility. Node mobility. Sink mobility. Event mobility.

30. Optimization Goals and Figures of Merit: How to optimize a network and How to compare these solutions? How to decide which approach is better? How to turn relatively inaccurate optimization goals into measurable figures of merit? For all the above questions the general answer is obtained from 1.Quality of service. 2. Energy efficiency. 3. Scalability. 4. Robustness.(QoS +scalability )

31. Gateway Concepts: The need for gateways

32. WSN to Internet communication

33. Internet to WSN communication

34. WSN tunneling:(Gateways can also act as simple extensions of one WSN to another WSN. )