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International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.

Durvesh Pilankar, Tanmay Sawant, Radhika Sule, Shweta Mahadeshwar / International
Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622
www.ijera.com Vol. 3, Issue 4, Jul-Aug 2013, pp.2506-2509
2506 | P a g e
Implementing Agricultural Applications Using Wireless Sensor
Network and Securing Them Using Advanced Encryption
Standard
Durvesh Pilankar1
, Tanmay Sawant2
, Radhika Sule3
, Shweta
Mahadeshwar4
1, 4
(Department of Electronics and Telecommunication, Vidyavardhini College of Technology, Maharashtra,
India,
2, 3
(Department of Electronics and Telecommunication, St. Francis Institute of Technology, Maharashtra, India,
ABSTRACT
A wireless sensor network (WSN) is a
large number of sensor nodes distributed
throughout large geographical area of interest.
These sensors monitor various conditions by
measuring different parameters like temperature,
pressure, sound, light intensity, heat, movement,
etc. The sensed data is routed to the sink node via
intermediate sensor nodes. Thus we get accurate
information about the parameters present in that
area. Application design can be simplified by
providing a set of programming primitives for
sensor networks that abstract the details of low-
level communication, data sharing, and collective
operations. The focus on sensor networks for
agriculture has a main topic of low power
consumption and efficient implementation of
hardware and software for various applications.
The security threats involved in wireless
technology cannot be ignored. Although difficult
to achieve it is inevitable to secure the wireless
communication network. For effective utilization
of the WSN commercially, a security system for
the wireless network is a must. Security aspect of
network is achieved using Advanced Encryption
Standard(AES) for data and Personal Area
Network(PAN) ID for node security. Our goal is to
confront an emerging technology with a concrete
problem of world-wide dimensions, the
sustainability of farming for small land-holders.
I. INTRODUCTION
A wireless sensor network (WSN) consists
of spatially distributed autonomous sensors to
monitor physical or environmental conditions, such
as temperature, sound, vibration, pressure, motion or
pollutants and to cooperatively pass their data
through the network to a main location. The nodes
sense environmental changes and report them to other
nodes over flexible network architecture. Sensor
nodes are great for deployment in hostile
environments or over large geographical areas.
Sensors usually communicate with each other using a
multi hop approach. The flowing of data ends at
special nodes called base stations (sometimes they
are also referred to as sinks).A base station links the
sensor network to another network (like a gateway)
to disseminate the data sensed for further processing.
Base stations have enhanced capabilities over simple
sensor nodes since they must do complex data
processing; this justifies the fact that bases stations
have workstation/laptop class processors, and of
course enough memory, energy, storage and
computational power to perform their tasks well.
Usually, the communication between base stations is
initiated over high bandwidth links.
Fig-1: Typical Wireless Sensor Network [9]
The idea of automating the collection of
physical data in order to monitor environments is not
new.
But recent technological advances have allowed for
the networking of a wide variety of sensors,
independently from any preexisting infrastructure.
Whenever physical conditions change rapidly over
space and time, WSNs allow for real-time data
processing at a minimal cost. Their capacity to
organize spontaneously in a network makes them
easy to deploy, expand and maintain, and provides
resilience to the failure of individual measurement
points.
II. ZIGBEE
Zigbee basically is built from low-power
digital radios used to create personal Area Networks.
Its based on IEEE 802.15 standard. Zigbee consumes
low power for operation which ensures longer battery
life for the equipments. Thus, equipments requiring
long battery period can be installed with ease. Other
notable advantages are low cost and ease of
implementation in any area. Zigbee can also be
Durvesh Pilankar, Tanmay Sawant, Radhika Sule, Shweta Mahadeshwar / International
Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622
www.ijera.com Vol. 3, Issue 4, Jul-Aug 2013, pp.
2507 | P a g e
implemented in cases where high data transfer rate is
not a necessity. All these factors make Zigbee highly
suitable and convenient for usage in the applications
related to agriculture.
III. SENSORS
It is a transducer which is used to measure
agricultural parameters. In this paper the agricultural
parameters discussed are „Temperature and Water
Level Indication‟ which are measured by using
Thermistor and Linear Variable Potentiometer
respectively. [1]
IV. SENSOR NODE
The sensors which we discussed above are
mounted on the node which contains microcontroller
as well as transreceiver module. The microcontroller
used here is AtMega328[2].It acts as a buffer and
also keeps a check on the frequency in which data is
passed to the transceiver module.
Now the sensor nodes within the network are making
discrete, local measurement of the area wherein they
are set up, communicating wirelessly and the
collected data is routed back to the user via sink(base
station).[3]
The transreceiver module i.e. ZigBee (XBEE 24 S2)
[4] will do the communication between the nodes in
the wireless sensor network. For interfacing between
the microcontroller and Xbee module here „Xbee
SHEILD‟ is used. Xbee module can be programmed
as per the requirement using the „X-CTU‟ software.
Programming parameters which are of prime
importance are Baud Rate, I/O Sampling and
Addressing.
V. OPERATION
Fig-2: Flow chart of „Node Development‟
A Zigbee network can be used in 3
topologies-star, tree and mesh. Depending upon the
need of the experiment these topologies can be used.
So here we have used the star topology wherein there
is one central node and 2 minor nodes which are
connected to central node and info travels via the
central node.
Fig-3: Star Network[10]
Basically, the Sensors mounted on sensor
node will pursue the condition and give appropriate
output to the respective microcontroller. The AtMega
will gauge the conditions and it will send the
essential data to the transreceiver module .While
doing so AtMega also simultaneously acts an analog
to digital convertor (ADC).Using interfacing devices
data is passed to the Transceiver module. Xbee
module will be used for the communication purpose.
As only two nodes are used in our project, we have
considered only 2 Xbee modules for on field work i.e
for water sensing and for checking temperature of the
soil so as to provide water for irrigation. At the base
station or the sink another Xbee module is used for
data reception from on field nodes. Each Xbee
module has unique PAN ID. This helps in
determining a unique identity to a particular node.
The one connected to the server computer is the
Coordinator while the others are Subordinators. Now
at the subordinator i.e at the node on field, data will
be sensed and further the processed data is
transmitted by the transreceiver. In our case the data
is directly transmitted to the base station as we have
considered only two on field nodes but an actual
WSN network consists of hundreds of nodes spread
across a vast area. Most of the energy of the battery is
consumed while transmitting the data and not while
sensing or processing the data. So when data is
transmitted from a node which is far away from a
base station, a lot of energy of the battery is utilized
and if done on a constant basis it will drain off the
energy from the battery thus making the node
completely useless for further operations. Once the
battery dies, node wont sense or transmit the
Development Sensor Board
Programming of AtMega
using Freeduno Board
Interfacing of sensors with
AtMega
Xbee configuration setup
(Differentiating between
Coordinator and router)
Implementation of Sensor
Node by Xbee interfacing
Durvesh Pilankar, Tanmay Sawant, Radhika Sule, Shweta Mahadeshwar / International
Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622
www.ijera.com Vol. 3, Issue 4, Jul-Aug 2013, pp.
2508 | P a g e
processed data hence special care must be taken for
this problem as energy saving is one of the most
important parameter of the WSN.Various protocols
have been mentioned over the years to save energy in
WSN eg. MECN,LEACH,SPIN etc.By using any of
these protocols energy of node can be saved thus
improving the performance in any application
Coordinator at the base station continuously accepts
inputs from the subordinators and it updates its
database accordingly. Thus the parameters are sensed
and required action will be taken.
VI. ATTACKS ON WSN
There are many small sensor nodes in a
sensor network and these are prone to various attacks.
But it is difficult to monitor each type of incoming
attacks. Physical, link, network, transportation and
application layers are basically the different types of
layers which gets affected during attacks [5].DOS
attacks (Denial Of Service Attacks)[6] are the ones
which affect the above mentioned layers.
In addition to DOS Attacks, there are several other
attacks on WSN such as Signal/radio jamming,
Device tampering Attack, Node Capturing attack,
Path Based DOS, Node Outage, Eavesdropping
which affects a lot of factors[7]
VII. SECURITY
Security in terms of protecting the
information transmitted on wireless networks is of
prime concern. The signal can be made difficult to be
intercepted or can be encrypted. This can be done by
employing easy steps such as reducing the signal
power to least possible level so that it is protected but
at the same time is able to cover the desired area,
turning off the service set identifier (SSID)
broadcasting by wireless access point, using
directional antennas which will ensure the signal is
transmitted only in the desired area.
Another technique is Encryption which is by
far the best method to secure the Wireless Sensor
Networks. Encrypting the signal increases the signal
security by a large amount.
Here the security provision is made
available by allotting unique PAN ID.PAN ID stands
for personal area network identifier, basically it is a
unique name given to each node. For example,
Subordinator1 has PAN ID of 2419 while
subordinator2 has PAN ID of 2420. PAN ID can
consist of numbers, symbols, characters etc. So
cracking it by obsolete method is obstinate. Another
way of providing security is memory addressing.
Thus a twofold security is provided to the system.
This gives node security or authentication to the
node. The data transmitted in the network is not
secure so there is a need of proper encryption
technique for data security. So for that Advanced
Encryption Standard (AES) is used for encryption.
The AES used in our case increases the
confidentiality of the message signal and hence
protects the information sent over the wireless
network
Fig-4: Flow chart of „Security Management‟
7.1 Advanced Encryption Standard
AES is a symmetric-key algorithm, meaning
the same key is used for both encrypting and
decrypting the data. AES is based on a design
principle known as a substitution-permutation
network. AES has a fixed block size of 128 bits and
a key size of 128, 192, or 256 bits. AES operates on a
4×4 column-major order matrix of bytes. The AES
cipher is specified as a number of repetitions of
transformation rounds that convert the input plaintext
into the final output of cipher text. Each round
consists of several processing steps, including one
that depends on the encryption key. A set of reverse
rounds are applied to transform cipher text back into
the original plaintext using the same encryption key.
Here while setting the configuration of Xbee we can
enable the AES i.e. data encryption by using a secret
key which is used at receiving end for decryption.
Hence data security is carried out.
VIII. EXPERIMENTAL RESULTS
8.1 LEVEL INDICATOR
Graph-1: Graphical Analysis of Water Level
Indicator
Development Of
Program
Maintain security using
AES with a private key
Communication between
nodes in secured way
Durvesh Pilankar, Tanmay Sawant, Radhika Sule, Shweta Mahadeshwar / International
Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622
www.ijera.com Vol. 3, Issue 4, Jul-Aug 2013, pp.
2509 | P a g e
The graph shown above indicates the level of water
in a reservoir. When the reading is maximum value it
indicates that the water in the reservoir is at its peak
and required action should be taken (for e.g. the
pumping can be continued).Now if the reading drops
to a low value then pumping should be stopped so as
to save water.
8.2 THERMISTOR
Graph-2: Graphical Analysis of „Thermistor‟
The graph explained above is that of cooling
thermistor .Here two sensors are used .One of which
is buried in the soil and the other one is exposed to
sunlight .The graph shows that when the outer
temperature is high compared to soil temperature
max reading is displayed and it shows the need of
irrigation.
IX. CONCLUSION
Wireless sensor networks have many
applications in our day to day life and it can be used
to play an important role for a number of agricultural
purposes such as soil moisture, water level and flow
detection for irrigational purposes. The results
obtained in the project are in accordance with the
facts .The prototype of two sensor nodes used in our
project can be modified and applied on a large scale
in farms .The temperature variations, flow control
and a variety of other parameters can be explored.
Security achieved by using AES encryption and PAN
ID paved way for the data transmitted to remain
secure. Power consumption and cost efficiency is
another aspect that is taken under consideration as the
nodes even operate in a power saver mode .Thus the
project helps a modern day farmer to combine
technology and agricultural expertise to yield large
profits and better product quality.
REFERENCES
[1]. Chee-Yee Chong, Srikanta P. Kumar, “
Sensor Networks: Evolution, Opportunities,
and Challenges”, pp.1247-1254,
Proceedings of the IEEE, Vol. 91, No. 8,
August 2003.
[2]. http://www.atmel.in/devices/ATMEGA328.
aspx?
[3]. Yazeed Al-Obaisat, Robin Braun,”On
Wireless Sensor Networks: Architectures,
Protocols, Applications, and Management”,
University of Technology, Sydney,
Australia.
[4]. Shahin Farahani ,”ZigBee Wireless
Networks and Transceivers”, Newnes
publications www.books.elsevier.com
[5]. Xiaojiang Du, Hsiao-Hwa Chen, „Security
in Wireless Sensor Networks, Proceedings
Of IEEE, Vol.15, No. 4, Aug. 2008
[6]. A. D. Wood , J. A. Stankovic, “Denial of
Service in Sensor Networks”, Computer,
vol. 35, no. 10, Oct.2002, pp. 54–62
[7]. Rina Bhattacharya,”A Comparative Study
Of Physical Attacks On Wireless Sensor
Networks”, International Journal Of
Research in Engineering And Technology,
Vol.2,No.1,Jan 2013
[8]. Xing Zhang, Jingsha He and Qian,”Security
Considerations on Node Mobility in
Wireless Sensor Networks”, 2009 Fourth
International Conference on Computer
Sciences and Convergence Information
Technology, pp. 1143-1146.
[9]. http://en.wikipedia.org/wiki/Wireless_sensor
_network
[10] Steven Kosmerchock,” Wireless Sensor
Network Topologies”

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Oj3425062509

  • 1. Durvesh Pilankar, Tanmay Sawant, Radhika Sule, Shweta Mahadeshwar / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 www.ijera.com Vol. 3, Issue 4, Jul-Aug 2013, pp.2506-2509 2506 | P a g e Implementing Agricultural Applications Using Wireless Sensor Network and Securing Them Using Advanced Encryption Standard Durvesh Pilankar1 , Tanmay Sawant2 , Radhika Sule3 , Shweta Mahadeshwar4 1, 4 (Department of Electronics and Telecommunication, Vidyavardhini College of Technology, Maharashtra, India, 2, 3 (Department of Electronics and Telecommunication, St. Francis Institute of Technology, Maharashtra, India, ABSTRACT A wireless sensor network (WSN) is a large number of sensor nodes distributed throughout large geographical area of interest. These sensors monitor various conditions by measuring different parameters like temperature, pressure, sound, light intensity, heat, movement, etc. The sensed data is routed to the sink node via intermediate sensor nodes. Thus we get accurate information about the parameters present in that area. Application design can be simplified by providing a set of programming primitives for sensor networks that abstract the details of low- level communication, data sharing, and collective operations. The focus on sensor networks for agriculture has a main topic of low power consumption and efficient implementation of hardware and software for various applications. The security threats involved in wireless technology cannot be ignored. Although difficult to achieve it is inevitable to secure the wireless communication network. For effective utilization of the WSN commercially, a security system for the wireless network is a must. Security aspect of network is achieved using Advanced Encryption Standard(AES) for data and Personal Area Network(PAN) ID for node security. Our goal is to confront an emerging technology with a concrete problem of world-wide dimensions, the sustainability of farming for small land-holders. I. INTRODUCTION A wireless sensor network (WSN) consists of spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, motion or pollutants and to cooperatively pass their data through the network to a main location. The nodes sense environmental changes and report them to other nodes over flexible network architecture. Sensor nodes are great for deployment in hostile environments or over large geographical areas. Sensors usually communicate with each other using a multi hop approach. The flowing of data ends at special nodes called base stations (sometimes they are also referred to as sinks).A base station links the sensor network to another network (like a gateway) to disseminate the data sensed for further processing. Base stations have enhanced capabilities over simple sensor nodes since they must do complex data processing; this justifies the fact that bases stations have workstation/laptop class processors, and of course enough memory, energy, storage and computational power to perform their tasks well. Usually, the communication between base stations is initiated over high bandwidth links. Fig-1: Typical Wireless Sensor Network [9] The idea of automating the collection of physical data in order to monitor environments is not new. But recent technological advances have allowed for the networking of a wide variety of sensors, independently from any preexisting infrastructure. Whenever physical conditions change rapidly over space and time, WSNs allow for real-time data processing at a minimal cost. Their capacity to organize spontaneously in a network makes them easy to deploy, expand and maintain, and provides resilience to the failure of individual measurement points. II. ZIGBEE Zigbee basically is built from low-power digital radios used to create personal Area Networks. Its based on IEEE 802.15 standard. Zigbee consumes low power for operation which ensures longer battery life for the equipments. Thus, equipments requiring long battery period can be installed with ease. Other notable advantages are low cost and ease of implementation in any area. Zigbee can also be
  • 2. Durvesh Pilankar, Tanmay Sawant, Radhika Sule, Shweta Mahadeshwar / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 www.ijera.com Vol. 3, Issue 4, Jul-Aug 2013, pp. 2507 | P a g e implemented in cases where high data transfer rate is not a necessity. All these factors make Zigbee highly suitable and convenient for usage in the applications related to agriculture. III. SENSORS It is a transducer which is used to measure agricultural parameters. In this paper the agricultural parameters discussed are „Temperature and Water Level Indication‟ which are measured by using Thermistor and Linear Variable Potentiometer respectively. [1] IV. SENSOR NODE The sensors which we discussed above are mounted on the node which contains microcontroller as well as transreceiver module. The microcontroller used here is AtMega328[2].It acts as a buffer and also keeps a check on the frequency in which data is passed to the transceiver module. Now the sensor nodes within the network are making discrete, local measurement of the area wherein they are set up, communicating wirelessly and the collected data is routed back to the user via sink(base station).[3] The transreceiver module i.e. ZigBee (XBEE 24 S2) [4] will do the communication between the nodes in the wireless sensor network. For interfacing between the microcontroller and Xbee module here „Xbee SHEILD‟ is used. Xbee module can be programmed as per the requirement using the „X-CTU‟ software. Programming parameters which are of prime importance are Baud Rate, I/O Sampling and Addressing. V. OPERATION Fig-2: Flow chart of „Node Development‟ A Zigbee network can be used in 3 topologies-star, tree and mesh. Depending upon the need of the experiment these topologies can be used. So here we have used the star topology wherein there is one central node and 2 minor nodes which are connected to central node and info travels via the central node. Fig-3: Star Network[10] Basically, the Sensors mounted on sensor node will pursue the condition and give appropriate output to the respective microcontroller. The AtMega will gauge the conditions and it will send the essential data to the transreceiver module .While doing so AtMega also simultaneously acts an analog to digital convertor (ADC).Using interfacing devices data is passed to the Transceiver module. Xbee module will be used for the communication purpose. As only two nodes are used in our project, we have considered only 2 Xbee modules for on field work i.e for water sensing and for checking temperature of the soil so as to provide water for irrigation. At the base station or the sink another Xbee module is used for data reception from on field nodes. Each Xbee module has unique PAN ID. This helps in determining a unique identity to a particular node. The one connected to the server computer is the Coordinator while the others are Subordinators. Now at the subordinator i.e at the node on field, data will be sensed and further the processed data is transmitted by the transreceiver. In our case the data is directly transmitted to the base station as we have considered only two on field nodes but an actual WSN network consists of hundreds of nodes spread across a vast area. Most of the energy of the battery is consumed while transmitting the data and not while sensing or processing the data. So when data is transmitted from a node which is far away from a base station, a lot of energy of the battery is utilized and if done on a constant basis it will drain off the energy from the battery thus making the node completely useless for further operations. Once the battery dies, node wont sense or transmit the Development Sensor Board Programming of AtMega using Freeduno Board Interfacing of sensors with AtMega Xbee configuration setup (Differentiating between Coordinator and router) Implementation of Sensor Node by Xbee interfacing
  • 3. Durvesh Pilankar, Tanmay Sawant, Radhika Sule, Shweta Mahadeshwar / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 www.ijera.com Vol. 3, Issue 4, Jul-Aug 2013, pp. 2508 | P a g e processed data hence special care must be taken for this problem as energy saving is one of the most important parameter of the WSN.Various protocols have been mentioned over the years to save energy in WSN eg. MECN,LEACH,SPIN etc.By using any of these protocols energy of node can be saved thus improving the performance in any application Coordinator at the base station continuously accepts inputs from the subordinators and it updates its database accordingly. Thus the parameters are sensed and required action will be taken. VI. ATTACKS ON WSN There are many small sensor nodes in a sensor network and these are prone to various attacks. But it is difficult to monitor each type of incoming attacks. Physical, link, network, transportation and application layers are basically the different types of layers which gets affected during attacks [5].DOS attacks (Denial Of Service Attacks)[6] are the ones which affect the above mentioned layers. In addition to DOS Attacks, there are several other attacks on WSN such as Signal/radio jamming, Device tampering Attack, Node Capturing attack, Path Based DOS, Node Outage, Eavesdropping which affects a lot of factors[7] VII. SECURITY Security in terms of protecting the information transmitted on wireless networks is of prime concern. The signal can be made difficult to be intercepted or can be encrypted. This can be done by employing easy steps such as reducing the signal power to least possible level so that it is protected but at the same time is able to cover the desired area, turning off the service set identifier (SSID) broadcasting by wireless access point, using directional antennas which will ensure the signal is transmitted only in the desired area. Another technique is Encryption which is by far the best method to secure the Wireless Sensor Networks. Encrypting the signal increases the signal security by a large amount. Here the security provision is made available by allotting unique PAN ID.PAN ID stands for personal area network identifier, basically it is a unique name given to each node. For example, Subordinator1 has PAN ID of 2419 while subordinator2 has PAN ID of 2420. PAN ID can consist of numbers, symbols, characters etc. So cracking it by obsolete method is obstinate. Another way of providing security is memory addressing. Thus a twofold security is provided to the system. This gives node security or authentication to the node. The data transmitted in the network is not secure so there is a need of proper encryption technique for data security. So for that Advanced Encryption Standard (AES) is used for encryption. The AES used in our case increases the confidentiality of the message signal and hence protects the information sent over the wireless network Fig-4: Flow chart of „Security Management‟ 7.1 Advanced Encryption Standard AES is a symmetric-key algorithm, meaning the same key is used for both encrypting and decrypting the data. AES is based on a design principle known as a substitution-permutation network. AES has a fixed block size of 128 bits and a key size of 128, 192, or 256 bits. AES operates on a 4×4 column-major order matrix of bytes. The AES cipher is specified as a number of repetitions of transformation rounds that convert the input plaintext into the final output of cipher text. Each round consists of several processing steps, including one that depends on the encryption key. A set of reverse rounds are applied to transform cipher text back into the original plaintext using the same encryption key. Here while setting the configuration of Xbee we can enable the AES i.e. data encryption by using a secret key which is used at receiving end for decryption. Hence data security is carried out. VIII. EXPERIMENTAL RESULTS 8.1 LEVEL INDICATOR Graph-1: Graphical Analysis of Water Level Indicator Development Of Program Maintain security using AES with a private key Communication between nodes in secured way
  • 4. Durvesh Pilankar, Tanmay Sawant, Radhika Sule, Shweta Mahadeshwar / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 www.ijera.com Vol. 3, Issue 4, Jul-Aug 2013, pp. 2509 | P a g e The graph shown above indicates the level of water in a reservoir. When the reading is maximum value it indicates that the water in the reservoir is at its peak and required action should be taken (for e.g. the pumping can be continued).Now if the reading drops to a low value then pumping should be stopped so as to save water. 8.2 THERMISTOR Graph-2: Graphical Analysis of „Thermistor‟ The graph explained above is that of cooling thermistor .Here two sensors are used .One of which is buried in the soil and the other one is exposed to sunlight .The graph shows that when the outer temperature is high compared to soil temperature max reading is displayed and it shows the need of irrigation. IX. CONCLUSION Wireless sensor networks have many applications in our day to day life and it can be used to play an important role for a number of agricultural purposes such as soil moisture, water level and flow detection for irrigational purposes. The results obtained in the project are in accordance with the facts .The prototype of two sensor nodes used in our project can be modified and applied on a large scale in farms .The temperature variations, flow control and a variety of other parameters can be explored. Security achieved by using AES encryption and PAN ID paved way for the data transmitted to remain secure. Power consumption and cost efficiency is another aspect that is taken under consideration as the nodes even operate in a power saver mode .Thus the project helps a modern day farmer to combine technology and agricultural expertise to yield large profits and better product quality. REFERENCES [1]. Chee-Yee Chong, Srikanta P. Kumar, “ Sensor Networks: Evolution, Opportunities, and Challenges”, pp.1247-1254, Proceedings of the IEEE, Vol. 91, No. 8, August 2003. [2]. http://www.atmel.in/devices/ATMEGA328. aspx? [3]. Yazeed Al-Obaisat, Robin Braun,”On Wireless Sensor Networks: Architectures, Protocols, Applications, and Management”, University of Technology, Sydney, Australia. [4]. Shahin Farahani ,”ZigBee Wireless Networks and Transceivers”, Newnes publications www.books.elsevier.com [5]. Xiaojiang Du, Hsiao-Hwa Chen, „Security in Wireless Sensor Networks, Proceedings Of IEEE, Vol.15, No. 4, Aug. 2008 [6]. A. D. Wood , J. A. Stankovic, “Denial of Service in Sensor Networks”, Computer, vol. 35, no. 10, Oct.2002, pp. 54–62 [7]. Rina Bhattacharya,”A Comparative Study Of Physical Attacks On Wireless Sensor Networks”, International Journal Of Research in Engineering And Technology, Vol.2,No.1,Jan 2013 [8]. Xing Zhang, Jingsha He and Qian,”Security Considerations on Node Mobility in Wireless Sensor Networks”, 2009 Fourth International Conference on Computer Sciences and Convergence Information Technology, pp. 1143-1146. [9]. http://en.wikipedia.org/wiki/Wireless_sensor _network [10] Steven Kosmerchock,” Wireless Sensor Network Topologies”