2. CONTENTS
WIRELESS SENSOR NETWORKS
Introduction
Types of WSN
Characteristics of a WSN
Architecture components of a WSN
Architecture of a WSN
Characteristics of a middleware
Concept of SOA for wireless networks
Architectural issues
Standards and Specifications
Applications
Challenges
Advantages
Disadvantages
Future Scope
Conclusion
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3. INTRODUCTION
Motivation of development
Parts of a sensor node in the network
Functions of a sensor node in the network
WIRELESS SENSOR NETWORKS
What is a wireless sensor network (WSN)…?
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Constraints
Cost
Size
Topology
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4. TYPES OF WIRELESS SENSOR NETWORKS
Dense collection of nodes
Ad-hoc
deployment
Difficulty in network
maintenance
Structured WSN
Few and scarcely
distributed nodes
Pre-planned deployment
WIRELESS SENSOR NETWORKS
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Unstructured WSN
Lower network
maintenance
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5. CHARACTERISTICS OF A WSN
Concurrency processing
3.
Low cost
4.
Restricted energy resources
5.
Tiny
6.
Small radio range
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Self – Organization
2.
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1.
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6. SOFTWARE ENGINEERING
Applications
- Sensor Applications
- Node Applications
- Sensor Network Applications
Sensor Application - Readout of a sensor , local storage of the data.
It has full access to the hardware and is able to access the operating
system directly.
Node Application - Application specific tasks and functions of the
middleware to build up and maintain the network
Sensor Network Application - Main tasks and required services of
the entire network
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Service oriented architecture
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7. CHARACTERISTICS OF A MIDDLEWARE FOR
SENSOR NETWORK
Primary objective of a middleware
A middleware has to be
Scalable
Generic
Adaptive
Reflective
1.
2.
3.
4.
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Middleware - software layer between operating system
and application
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8. CONCEPT OF SOA FOR WIRELESS NETWORKS
Example of a simple service architecture
WIRELESS SENSOR NETWORKS
A simple use case can help determine the software
architecture.
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9. ARCHITECTURE OF NODE APPLICATION
STRUCTURE
1.
3.
Node software has 3 parts
Operating System which performs device-specific tasks
Sensor Driver which initializes the sensor hardware and performs
the measurements in the sensor
Host Middleware which organizes the co- operation of the
distributed nodes in the network
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2.
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10. OVERALL GENERAL ARCHITECTURE
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WIRELESS SENSOR NETWORKS
The general overall software architecture of the sensor
net is shown in the figure
Individual nodes interact with the distributed
middleware layer to perform the functions dictated by
the sensor network application
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11. ARCHITECTURAL ISSUES
Network topology
Failure in long range communication
Increase in traffic decreases the lifetime
Single tier and multi tier architecture disadvantages
WIRELESS SENSOR NETWORKS
Energy efficiency
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12. ARCHITECTURE – CLUSTER BASED
Provides Quality of management (Qos)
Dynamic architecture – cluster is a basic unit of software
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Proposed to tackle the previous architectural issues
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13. STANDARDS AND SPECIFICATIONS
2.
3.
WIRELESS SENSOR NETWORKS
1.
Predominant standards commonly used in WSN
communications include:
Zig Bee - Transmit data over long distances by passing
data through intermediate devices to reach more
distant ones
Bluetooth - Wireless technology standard for
exchanging data over short distances from fixed and
mobile devices by creating PANs’
6LoWPAN - Defined encapsulation and header
compression mechanisms that allow IPv6 packets to be
sent to and received from over IEEE 802.15.4 based
networks
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14. APPLICATIONS OF WSN
Health care monitoring
Air pollution monitoring
Forest fire detection
Landslide detection
Water quality monitoring
Natural disaster prevention
WIRELESS SENSOR NETWORKS
Area monitoring
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Industrial monitoring
16. ADVANTAGES OF A WSN
Can accommodate new devices at any time
Flexible to go through physical partitions
It can be accessed through a centralized monitor
Infrastructure
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Avoids a lot of wiring
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17. DISADVANTAGES OF WSN
Comparatively low speed of communication
Gets distracted by various elements
Costly at large
Life of nodes
Energy life
WIRELESS SENSOR NETWORKS
Easy for hackers to hack a network
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18. FUTURE SCOPE
Needs to be implemented in a wireless sensor network
with mobile nodes.
The effects of very large node densities need to be
investigated.
The feasibility of using the clustering technique and data
aggregation needs to be tested in the same wireless
sensor network.
WIRELESS SENSOR NETWORKS
More research work needs to be done in future.
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19. CONCLUSION
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WIRELESS SENSOR NETWORKS
As described, wireless sensor networks possess the
potential for many applications. The advance of
technology enabled the creation of prototype WSNs, but
the hardware and software both have a ways to go before
WSNs are practical, cost-effective, and usefully.
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