A Survey on Energy Efficient MAC Protocol for Wireless Sensor Networks

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A Survey on Energy Efficient MAC Protocol for
Wireless Sensor Networks

• Huma Naushad

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Sensor Networks

• Sensor nodes are low cost, low power,
  multifunctional electronic devices.
• Small in size
• Wireless communication over short distances.
• Sensors have Sense, data processing and
  communicating components.
• A sensor network is composed of densely deployed
  sensor nodes.

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Applications

• Military
• military command, control, communications,
  computing intelligence, targeting systems.
• Health
• monitor patients, assist disabled patients.
• Others
• managing inventory, monitoring product
  quality, monitoring disaster areas.

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Protocol Stack

• Physical layer
• addresses simple but robust modulation,
  transmission and receiving techniques.
• Data Link Layer
• -Is responsible for multiplexing of data
  streams, data frame detection, medium access and
  error control.
• -Medium access control MAC a sub-layer.
• Network Layer
• routes data supplied by transport layer.

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Protocol Stack

• Transport Layer
• maintains flow of data
• Application Layer
• depends on sensing tasks
• Power Management Plane
• manages how sensor node uses its power

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Protocol Stack

• Mobile Management Plane
• detects and registers node movement
• Task Management Plane
• balances and schedules sensing tasks given to a
  specific region

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Power Consumption

• Wireless sensor node is an microelectronic
  device can be equipped with limited power source.
• Replenishment of power resource might be
  impossible, sensor lifetime shows a strong
  dependence on battery lifetime.
• Power consumption is divided into 3 domains
• -Sensing
• -Communicating
• -Data processing.

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Energy efficiency in MAC protocols

• Major sources of energy waste
• Collision
• Idle listening
• Overhearing
• Control packet overhead

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Schedule based protocols

• Time slots are pre-allocated on the bases of
  time, code or frequency to individual nodes
• Examples
• -LEACH
• - Sohrabi Pottie
• - Bluetooth.
• Energy conservation
• -Collision free
• - low duty cycle operation
• -overhearing avoidance.
• Disadvantages-time slots are wasted
• -not flexible to changes
• - lack peer to peer communication.

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Contention based protocols

• Common channel is shared between nodes
• Examples
• -MACA
• - MACAW
• Energy conservation
• -Piconet
• -PAMAS
• - IEEE 802.11
• Disadvantages
• -Idle listening
• - collision.

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Energy efficient MAC protocols

• SMAC
• TMAC
• TRAMA
• Power efficient System
• Cluster Based energy efficient scheme

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Proposal

• Study some of the classic and state of the art
  energy efficient protocols for wireless sensor
  networks. The survey article would capture their
  comparative study and any room for further
  improvements.