Sensor Network MAC protocol

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Sensor Network MAC protocol Applications

• KIRAN KUMAR REDDY V
• LENIN THUMMALAPALLI

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802.11
Network Delay
Power Used
Sensor Application
802.11
time
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S-MAC

• Identified that radio is consuming more power.
• Made radio sleep some duration of frame.

Network Delay
S-MAC 10
Power Used
Sensor Application
802.11
S-MAC
time

• S-MAC 100 is equivalent to 802.11

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T-MAC

• Why radio should do idle listening for 10 of
  frame length.
• used a small time out.

Network Delay
Power Used
Sensor Application
802.11
S-MAC
T-MAC
time

• Under homogenous traffic T-MAC is equivalent to
  S-MAC

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B-MAC

• Radio is using Threshold mechanism for Clear
  Channel Assessment. Due to
• environmental variations, noise is considered
  as channel is idle.
• For efficient CCA outlier is used instead of
  threshold.

Network Delay
Power Used
Sensor Application
B-MAC
802.11
S-MAC
T-MAC
time

• In a scenario where threshold doesnt give false
  negatives, B-MAC
• and T-MAC are equivalent

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Change in Trend

• What S-MAC, T-MAC, B-MAC are doing?
• Trying to minimize idle listening as much as
  possible.
• Why radio should listen the channel?
• To minimize collisions.
• How can we make collision free without listening
  the channel?
• TDMA
• TDMA is not adaptable to Network changes where
  as CSMA is adaptable to network changes.
• Combine the best features of CSMA and TDMA,
• introduced schedule based protocol.
• How can we do Time synchronization?
• External GPS reciever can be used.

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TRAMA

• TRAMA is schedule based protocol.
• Frame consists of two periods Random Access
  period, Schedule Access period.

Random Access Period (CSMA based)
Schedule Access Period (TDMA based )
To adapt to Network Changes
To transfer data collision free
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TRAMA
Network Delay
Power Used
Sensor Application
802.11
S-MAC
T-MAC
B-MAC
TRAMA
time
If we cant provide Time synchronization
externally TRAMA is not applicable.
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Consider the following scenario
Data initiators
Forwarders
Base Station

• What Forwarders are doing?
• Just routing data to base station. Forwarders
  have to wake up for
• longer time, it may lose its power quickly.
• If one Forwarder is dead, initiators
  choose a path of longer
• distance. It will be difficult to replace
  the dead motes in sensor field

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PEDAMACS

• Provided solution to above scenario.
• Deploy extra motes outside network field. Supply
  unlimited power to these
• extra motes

Access Point
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PEDAMACS
Network life time with PEDAMACS depends on
optimal placement of Access points
Network Delay
Power Used
Sensor Application
PEDAMACS
802.11
S-MAC
T-MAC
B-MAC
TRAMA
time

• In an application where no scope to deploy
  Access points, PEDAMACS is
• same as TRAMA. In PEDAMACS Access point
  provides Time
• Synchronization.

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Conclusion

• Sensor application can be designed using 802.11
  also.
• But Network life time will be in terms of
  hours.
• Some amount of delay can be accepted in sensor
  applications. So, researchers are trying to
  minimize the power usage by increasing delay.
• An ideal MAC protocol is one which makes power
  usage
• almost zero with an acceptable delay.
• Habitat monitoring Application can be
  redesigned using PEDAMACS to achieve greater
  network life time.
• But Military surveillance application
  cannot use Access points. For matter of
  stealthiness GPS receiver. B-MAC is suggestable.

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Counter sniper Application

• Acoustic signals, such as muzzle blasts and shock
• waves provide the easiest and most accurate way
• to detect shot.

Applicable MAC S-MAC, T-MAC, B-MAC, and
TRAMA. TRAMA is best suitable.
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Marine Microorganism Detection

• Regions of sharp temperature change in oceans
• (thermoclines) are a breeding ground for certain
• marine microorganisms.

Applicable MAC S-MAC, T-MAC, B-MAC. B-MAC is
best suitable.
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Volcanic Eruption Detection

• Volcanic Earthquake radiates acoustic waves
• into atmosphere and seismic waves into the
• ground.

Applicable MAC S-MAC, T-MAC, B-MAC, TRAMA and
PEDAMACS. PEDAMACS is best suitable.
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Military Surveillance system

• Detecting Vehicles in restricted area based on
  the magnetic distortions caused by the vehicles

Applicable MAC S-MAC, T-MAC, B-MAC, TRAMA
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Traffic Monitoring System

• Based on the magnetic distortions generated by
  the Vehicles.

Applicable MAC PEDAMACS, S-MAC, B-MAC, T-MAC,
TRAMA. Best suitable PEDAMACS.
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• Questions ?

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• THANK YOU