2. Group members
Attia Iqbal
Hafsa Rashid
Maria Sharif
2
Fatima Jinnah Women University Rawalpindi
3. TOPIC
Low Power MAC For Wireless Sensor
Networks
3
Fatima Jinnah Women University Rawalpindi
4. MAC
Medium access control or media access control (MAC) layer is
the lower sublayer of the data link layer (layer 2) of the seven-
layer OSI model
4
Fatima Jinnah Women University Rawalpindi
5. Low power MAC for WSNs
Networks that consists of sensors which are distributed in an ad
hoc manner
Low-power MAC protocol, for low-traffic wireless sensor
network.
Low power MAC for Wireless sensor networks consists of
protocols and algorithms
5
Fatima Jinnah Women University Rawalpindi
6. Types of MAC protocols
There are three types of mac protocols:
1. Fixed-allocation
2. Demand-based
3. Contention-based
6
Fatima Jinnah Women University Rawalpindi
7. Fixed-allocation MAC protocol
Share the common medium
It is suitable for sensor network that continuously monitor
and generate deterministic data traffic
Provide a bounded delay for each node
7
Fatima Jinnah Women University Rawalpindi
8. Demand-based MAC protocol
Channel is allocated according to the demand of the node
Variable rate traffic can be efficiently transmitted
Require the additional overhead of a reservation process
8
Fatima Jinnah Women University Rawalpindi
10. Subsystem of node
Each node of the sensor networks consist of three subsystem:
1. Sensor subsystem
2. Processing subsystem
3. Communication subsystem
10
Fatima Jinnah Women University Rawalpindi
11. Sensor subsystem: Senses the environment
Processing subsystem: Performs local computations on the
sensed data
Communication subsystem: Responsible for message
exchange with neighboring sensor nodes
11
Fatima Jinnah Women University Rawalpindi
12. Energy efficient wireless MAC protocol
There are four sources of energy waste:
1. Idle listening
2. Overhearing
3. Collisions
4. Protocol overhead
12
Fatima Jinnah Women University Rawalpindi
13. Idle listening: Idle listening refers to the active listening to an
idle channel
Overhearing: Receive packets destined to others
Collisions: Multiple senders want to talk
Protocol overhead: It refers to the packet headers and the
signaling required by the protocol in addition to the
transmission of data payloads
13
Fatima Jinnah Women University Rawalpindi
14. Energy efficient system extends the WSN’s lifetime and
increases its computational capabilities
14
Fatima Jinnah Women University Rawalpindi
15. Duty-cycling
It is a primary technique significantly improving the energy
efficiency of Wireless Sensor Networks (WSNs)
15
Fatima Jinnah Women University Rawalpindi
16. Types of duty-cycling
1. Synchronous duty-cycling
2. Asynchronous duty-cycling
16
Fatima Jinnah Women University Rawalpindi
17. Synchronous duty-cycling: In synchronous duty-cycling, all
nodes have synchronized duty cycles
Asynchronous duty-cycling: , In asynchronous duty-cycling,
nodes have their own duty cycles
17
Fatima Jinnah Women University Rawalpindi
18. Power consumption
A large number of sensor nodes
cheap batteries
18
Fatima Jinnah Women University Rawalpindi
19. Example
Switching the RF(radio frequency) transceiver
19
Fatima Jinnah Women University Rawalpindi
20. Types of transmission
1. Uplink (from the sensor nodes to the access point)
2. Downlink (from the access point to the sensor nodes)
20
Fatima Jinnah Women University Rawalpindi
21. 21
Uplink transmission
Access points can listen all the time to the channel
Multiple access to the channel
Downlink transmission
Data transmission without requiring sensor nodes
continuously listen to the channel
Tradeoff between power consumption and transmission delay
Fatima Jinnah Women University Rawalpindi
22. If the medium is found busy, a sensor node continues to listen
until a data frame is received or until the medium becomes idle
again
22
Fatima Jinnah Women University Rawalpindi
23. Researches about MAC
Liao introduced a high performance low-power 32-bits MAC
with Single-Instruction-Multiple-Data (SIMD) feature.
Elguibaly proposed a merged MAC operation and gave an
analytical overview of how his technique optimizes the MAC
hardware.
Murakami et al. adopted the half array implementation to
design a high speed and area-effective MAC architecture.
Raghuneth et al. made use of a carry-save multiplier that can
simplify sign extension and saturation, and further applies it on
the MAC architecture to reduce the unit’s area and power
consumption.
23
Fatima Jinnah Women University Rawalpindi
24. The 32-bit MAC unit architecture is very large, so the 8-bit
MAC unit architecture is used
24
Fatima Jinnah Women University Rawalpindi
25. Applications OF Low power MAC for WSNs:
Health care monitoring
Air pollution monitoring
Landslide detection
Water quality monitoring
Natural disaster prevention
Industrial monitoring
Area monitoring
25
Fatima Jinnah Women University Rawalpindi
26. References
1. http://www.slideshare.net/shikhathegreat/ppt-on-low-power-wireless-sensor-network-
5th-sem
2. Won, Myounggyu, Taejoon Park, and Sang H. Son. "Asym-MAC: A MAC Protocol for
Low-Power Duty-Cycled Wireless Sensor Networks with Asymmetric Links." IEEE
Communications Letters 18.5 (2014): 809-812.
3. Shi, Xiaolei, and Guido Stromberg. "SyncWUF: An ultra low-power MAC protocol for
wireless sensor networks." IEEE Transactions on Mobile Computing 6.1 (2007): 115-
125.
4. Abdelgawad, A. "Low power multiply accumulate unit (MAC) for future Wireless
Sensor Networks." Sensors Applications Symposium (SAS), 2013 IEEE. IEEE, 2013.
5. El-Hoiydi, Amre, and J-D. Decotignie. "WiseMAC: an ultra low power MAC protocol
for the downlink of infrastructure wireless sensor networks." Computers and
Communications, 2004. Proceedings. ISCC 2004. Ninth International Symposium on.
Vol. 1. IEEE, 2004.
26
Fatima Jinnah Women University Rawalpindi