PRESENTED BY S.RAMANATHAN

I B.C.A

Wireless Sensor Networks: A Detailed Survey

CONTENTS2

IntroductionApplications of sensor networksFactors influencing sensor network designCommunication architecture of sensor

networksConclusion

Introduction3

A sensor network is composed of a large number of sensor nodes, which are densely deployed either inside the phenomenon or very close to it.

Random deploymentCooperative capabilities

Applications of sensor networks4

TemperatureHumidityVehicular movementLightning conditionPressureSoil makeupNoise levelsThe presence or absence of certain kinds of objectsMechanical stress levels on attached objectsThe current characteristics such as speed,

direction, and size of an object

SIMPLE PICTURE5

Applications of sensor networks6

Military applicationsMonitoring friendly forces, equipment and

ammunitionBattlefield surveillanceReconnaissance of opposing forces and

terrainBattle damage assessmentNuclear, biological and chemical attack

detection and reconnaissance

Applications of sensor networks7

Environmental applicationsForest fire detectionFlood detectionPrecision agriculture

Applications of sensor networks8

Health applicationsTele monitoring of human physiological dataTracking and monitoring patients and doctors

inside a hospitalDrug administration in hospitals

Home applicationsHome automationSamrt environment

Factors influencing sensor network design

9

Fault tolerance Fault tolerance is the ability to sustain

sensor network functionalities without any interruption due to sensor node failures.

The fault tolerance level depends on the application of the sensor networks

Scalability Scalability measures the density of the

sensor nodes.

Factors influencing sensor network design

10

Production costsThe cost of a single node is very important

to justify the overall cost of the networks.The cost of a sensor node is a very

challenging issue given the amount of functionalities with a price of much less than a dollar.

Factors influencing sensor network design

11

Hardware constraints

Factors influencing sensor network design

12

Sensor network topology

Pre-deployment and deployment phasePost-deployment phaseRe-deployment of additional nodes phase

Factors influencing sensor network design

13

Transmission media In a sensor network, communicating

nodes are linked by a wireless medium. To enable global operation, the chosen transmission medium must be available worldwide.

Radio infrared optical media

Factors influencing sensor network design

14

Power consumption

SensingCommunicationData processing

Communication architecture of sensor networks

15

Communication architecture of sensor networks

16

Communication architecture of sensor networks

17

Application layer The three possible application layer protocols

are -Sensor management protocol (SMP)Task assignment and data advertisement

protocol (TADAP)Sensor query and data dissemination protocol

(SQDDP)

Communication architecture of sensor networks

18

Transport layerThis layer is especially needed when the

system is planned to be accessed through Internet or other external networks.

No attempt thus far to propose a scheme or to discuss the issues related to the transport layer of a sensor network in literature.

Communication architecture of sensor networks

19

Network layerPower efficiency is always an important

consideration.Data aggregation is useful only when it does

not hinder the collaborative effort of the sensor nodes.

An ideal sensor network has attribute-based addressing and location awareness.

Communication architecture of sensor networks

20

Data aggregation

Communication architecture of sensor networks

21

Data link layer The data link layer is responsible for the

medium access and error control. It ensures reliable point-to-point and point-to-multipoint connections in a communication network.

Medium access controlCreation of the network infrastructure Fairly and efficiently share communication

resources between sensor nodes

Communication architecture of sensor networks

22

Power saving modes of operation Operation in a power saving mode is energy

efficient only if the time spent in that mode is greater than a certain threshold.

Error controlForward Error Correction (FEC) Automatic Repeat Request (ARR)Simple error control codes with low-

complexity encoding and decoding might present the best solutions for sensor networks.

Communication architecture of sensor networks

23

Physical layerThe physical layer is responsible for frequency

selection, frequency generation, signal detection, modulation and data encryption.

CONCULSIONFlexibility and fault tolerance create exciting new

applications for remote sensingIn future the wide range of applications will make

sensor networks an integral part of our lives THANK YOU

24

ANY QUERYS ?