shyam shinde
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Transcript of shyam shinde
SEMINAR PRESENTATION ONUNDERWATER WIRELESS
COMMUNICATION
GUIDED BY:
Prof. G.M.Dahane
SUBMITTED BY :
S.M.Shinde
4/2/2014 1
OUTLINE
• Introduction
• History
• Underwater Wireless Communication System
• Attacks and counter measures
• Necessity of Underwater Wireless Communication
• Conclusion
• References
4/2/2014 2
INTRODUCTION
• Underwater wireless communication is thewireless communication in which acoustic signals(waves) carry digital information through anunderwater channel.
• The signal that are used to carry digitalinformation through an underwater channel areacoustic channel.
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The science of underwater acoustics began in 1490,
when Leonardo Da Vinci, stated.
In 1687 Isaac Newton wrote his Mathematical
Principles of Natural Philosophy which included the first
mathematical treatment of sound in water.
HISTORY
4/2/2014 4
Underwater Wireless Communication System
• Radio waves do not propagate well underwater due to the high energy absorption of water.
• Therefore, underwater communication are based onacoustic links characterized by large propagation delays.
• Acoustic channels have low bandwidth.
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Underwater Wireless Communication System
• The signal that are used to carry digital information through an underwater channel are acoustic channel.
• The propagation speed of acoustic signals in water is typically 1500 m/s.
• It cannot rely on the Global Positioning System (GPS).
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WAVE PROPAGATION
•This is an multipath propagation in water.
•In shallow water, multipath occurs due to signal reflection from the surface and bottom.
•In deep water, it occurs due to ray bending.
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satellite
onshore sinks
AutonomousUnderwaterVehicle
Surface sink
Surface Station
Acoustically connected SensorsSensors4/2/2014 8
ATTACKS AND COUNTER MEASURES…….
Jamming
Wormhole attacks
Sybil attack
SelectiveForwarding
Acknowledgment
Spoofing
ATTACKSHello Flood
attack
SinkholeAttacks
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Jamming
Method of Attack
Countermeasures
•The transmission of data packets continuously so that the wireless channel get completely blocked.
•Spread spectrum techniques.
•Sensors can switch to sleep mode
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Wormhole Attack
Method of attack
•False neighborhood relationship are created..
Countermeasures
•Estimating the direction of arrival…
4/2/2014 11
Authentication
•Proof that data was sent by a legitimate user
Integrity
•Information is not altered.
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Confidentiality
•Information is not accessible to unauthorized parties.
Availability
•Data should be available when needed by an authorized user.
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HARDWARE PLATFORM INTERFACES
Sensor Interface:
Wide (constantly changing) variety of sensors,sampling strategies.
Hardware:
Software Defined Acoustic Modem (SDAM)
Communication Interface:
Amplifiers, Transducer Signal modulation4/2/2014 14
ARCHITECTURE OF ACOUSTIC MODEM
• It improves the signal to noise ratio.
• which reduces bit error rate to less than 10.
Parts of an acoustic modem:
• DSP Board
• AFE(Analog Front End) Board
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DATA TRANSMISSION IN MODEM
• When no data is being transmitted, the modem stays insleep mode.
• The modem receives data from its link in sleep mode andthen switches to transmit mode and transmit the data.
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NECESSITY OF UNDERWATER WIRELESS COMMUNICATION
Wired underwater is not feasible in all situations asshown below-:
• Temporary experiments
• Breaking of wires
• Significant cost of deployment
• Experiment over long distances.
To cope up with above situations, we requireunderwater wireless communication.
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ADVANTAGES
•Can be used to provide early warnings of
tsunamis generated by undersea earthquakes.
•It avoids data spoofing.
•It avoids privacy leakage.
•Pollution monitoring.
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• Battery power is limited and usually batteries cannot be recharged also because solar energy cannot be exploited .
•The available bandwidth is severely limited.
• Channel characteristics including long and variable propagation delays.
•Multipath and fading problems.• High bit error rate.
DISADVANTAGES
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• The aim of this is to build a acoustic communication.
• This is not only the way for underwater communication.
• By using optical waves which offers higher throughput (Mbps) over short distances (up to about 100 m) .
CONCLUSION
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