1. Energy Efficiency • Energy consumption is the most important factor to determine the life of sensor network. • since sensors networks has low power resources, it make energy optimization more complicated. • Prolonging the life of network can be done by energy awareness.

2. Energy Efficiency ( Continued ) • Sensor network usually contain four subsystems: 1- Computing subsystem. 2- Communication subsystem. 3-Sensing Subsystem. 4- Power supply Subsystem.

3. Energy Efficiency ( Continued ) • Computing subsystem: - It consists of microcontroller unit (MCU). - MCU is responsible for the control of the sensor & execution of communication protocols. - MCU works under various operating mode of power consumption.

4. Energy Efficiency ( Continued ) • Computing subsystem: - Shuttling between different modes of operations involves consumption of power. - energy consumption level of the various modes should be considered at each node.

5. Energy Efficiency ( Continued ) • Communication subsystem: - It consists of short range radio system. - It used to communicate with neighboring nodes and the outside world. - Transmitting and receiving operation consume high energy.

6. Energy Efficiency ( Continued ) • Communication subsystem: - Energy can be reduced by shutdown (sleep mode) the radio when there is no need to communication.

7. Energy Efficiency ( Continued ) • Sensing subsystem: - It consists of group of sensors and links to the outside world. - Energy consumption can be reduced by using low power components.

8. Energy Efficiency ( Continued ) • Power supply subsystem: - It consists of a battery which supplies power to the node. - Energy can be reduced by reducing the amount of current drawn from the battery.

9. Energy Efficiency ( Continued ) • Sensor node acts a router. - Intelligent hardware that helps in redirecting packets which need to be forwarded reduce power consumption. - No overheads computing processes are needed.

10. Energy Efficiency ( Continued ) • Updating the health of network would serve as a warning. - This warning could save energy in case of failure or malfunction.

11. Sensor VS Ad-HocNetworks • One gateway node. • Communication between pair of nodes is not specific.

12. Sensor VS Ad-HocNetworks • Not Dynamic (i.e. sensors are not mobile). - In some applications WSN can contain some mobile/robotic nodes with moving capabilities. - Generally, dynamic of WSN involves nodes the network because of system failure or power depletion.

13. Routing Protocols in Sensors Network • WSN use the same Protocols in Ad-Hoc Network. • Routing Algorithms can be classified into two main categories : 1- Proactive Protocols. 2- Reactive Protocols.

14. Routing Protocols in Sensors Network • Proactive Protocols: - Destination Sequenced Distance Vector routing protocol (DSDV). - Path-Finding Algorithms (PFA). - Wireless Routing Protocols (WRP).

15. Routing Protocols in Sensors Network • Reactive Protocols: - Gafni and Bertsekans’s algorithm. - Dynamic Source Routing protocol (DSR). - Temporally Ordered Routing Algorithm Routing protocol (TORA). - Associative-Based Routing protocol (ABR).

16. Routing Protocols in Sensors Network • Reactive Protocols: - Ad-Hoc On demand Distance Vector (AODV). - Signal Stability-Based Routing protocol (SBR). - Location Aided Routing algorithm (LAR). - Power Aware Routing protocol (PAR).