an adaptive mac protocol for wireless sensor networks wen-hwa liao, hsiao-hsien wang, and wan-chi...
DESCRIPTION
Introduction In WSNs, the sensors are used to sensing, calculating, and transmitting data. Each sensor equips with battery and works individually. The power of sensor is supplied by battery.TRANSCRIPT
![Page 1: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/1.jpg)
AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS
Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi WuPIMRC’07
![Page 2: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/2.jpg)
Outline Introduction Related work Asynchronous MAC(AMAC) protocol Simulation Conclusion
![Page 3: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/3.jpg)
Introduction In WSNs, the sensors are used to sensing , calculating, and transmitting data. Each sensor equips with battery and works individually. The power of sensor is supplied by battery.
![Page 4: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/4.jpg)
Introduction Because of technical limitations, the
power carried by sensor is very limited. To replace battery is very time
consuming and costly process. There are a lot of researches on energy
saving. Ex:
Hardware Operating mechanism
![Page 5: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/5.jpg)
Introduction - motivation
The sleeping mechanism is one of the most effective energy saving method. In order to conserve energy, the sensor turns its antenna off when it doesn’t have to transmit data. Because the topology of WSNs may change frequently, the saving mechanism should be distributed and self-organized.
![Page 6: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/6.jpg)
Related work - SMAC
Each sensor has its fixed wake-up schedule.
The sensor exchanges their schedules by broadcasting it to all its immediate neighbors.
W. Ye, J. Heidemann, and D. Estrin, “An Energy-Efficient MAC Protocol for Wireless Sensor Networks,” IEEE INFOCOM , 2002.
Listen ListenSleep SleepTime
Schedule
![Page 7: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/7.jpg)
Related work - SMAC
A B
B’s schedule
Listen ListenSleep Sleep
Listen ListenSleep Sleep
A
B Time
![Page 8: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/8.jpg)
Related work - PMAC Sensor generates sleeping schedule based
on its own traffic periodically. Pattern string
Bit 1 indicates wake-up Bit 0 means sleep
Period N time slots
The sensor also exchanges their schedules by broadcasting it to all its immediate neighbors.
TDMA systemT. Zheng, S. Radhakrishnan, and V. Sarangan, “PMAC: An Adaptive Energy-Efficient MAC Protocol for Wireless Sensor Networks,” IEEE International Parallel and Distributed Processing Symposium (IDPDS), 2005.
![Page 9: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/9.jpg)
Related work – PMAC schedule
Time is divided into super time frames (STF)
STF STF STF
Time
PRTF PETF
WN slots
Period i Period i+1 Period i+2
0 0 1 10 0 …
Exchange the schedule of i+2
![Page 10: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/10.jpg)
Related work - PMAC
δ is a predefine threshold. The time slot in a period will be repeated, if pattern is small than the size of period N Schedule is composed of sleep-wakeup pattern
Ex: 1, 011, 021, 041, · · · 0m1, 0m01, for m ≤δ
1,01,001,00001 ,δ=4 0δ 02 1, 0δ 03 1, · · · 0N−1 1. for δ≤m ≤N
0401,04001 δ=4
![Page 11: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/11.jpg)
Related work - PMAC
PRTF PETF
W6 slots
0 0 1 10 0 …
Pattern:001m= 2
δ=4 , N=6
Time
Pattern:00001m =4
Pattern:000001m =5
Update Pattern
PRTF PETF
W6 slots
0 0 0 10 0 …
Time
Update Pattern
![Page 12: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/12.jpg)
Related work - PMAC
The drawback of PMAC Sensor is necessary to exchange it
own schedule for neighbor discovery. PMAC is required to achieve clock
synchronous.
![Page 13: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/13.jpg)
Related work – quorum based
R. Zheng, J. C. Hou, and L. Sha, “Asynchronous Wakeup for Ad Hoc Networks,” ACM International Symposium on Mobile Ad Hoc Networking & Computing (Mobihoc), 2003.
0 1 2 34 5 6 78 9 10 1112 13 14 15
Host A
Host B
r1 r2
c2
c1
Asynchronous method
![Page 14: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/14.jpg)
AMAC – goal Design a hybrid protocol
time asynchronous schedule Quorum system
traffic-aware schedule PMAC
![Page 15: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/15.jpg)
AMAC -modify pattern string to adapt to quorum
Problem with PMAC between quorum The original Pattern is not compatible Ex:
Original pattern 001
0 0 1 0 0 10 0 1 0 0 10 0 1 0 0 10 0 1 0 0 10 0 1 0 0 10 0 1 0 0 1
![Page 16: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/16.jpg)
AMAC -modify pattern string to adapt to quorum
Replace the original sleep-wakeup string bit
1 => 111…1 =>1n
0 => 000…1 =>0n-11
![Page 17: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/17.jpg)
AMAC - modify pattern string to adapt to quorum Origin PMAC pattern
(000..)m-11 Exchange to new pattern
{(0n-11)(0n-11) (0n-11)}m-1 1n
1N represents selected column in quorum
The other 0n-11 forms the selected row in quorum
0 0 0 0 10 0 0 0 10 0 0 0 1 … …0 0 0 0 11 1 1 1 1
n
c
r
m
![Page 18: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/18.jpg)
AMAC – traffic aware
Total time slot is also N slots N=n*m Pattern
(0n-11) 1n0 0 0 0 0 11 1 1 1 1 10 0 0 0 0 11 1 1 1 1 10 0 0 0 0 11 1 1 1 1 1
![Page 19: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/19.jpg)
AMAC – different size
Pattern 000001 111111
Pattern 000101 000101
1111110 0 0 0 0 11 1 1 1 1 10 0 0 0 0 11 1 1 1 1 10 0 0 0 0 11 1 1 1 1 1
0 0 0 1 0 00 0 0 1 0 01 1 1 1 1 10 0 0 1 0 00 0 0 1 0 01 1 1 1 1 1
![Page 20: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/20.jpg)
Simulation 100 sensors nodes Duty cycle 100 time slots Execution time 1000~10000 time
slot Schedule pattern is re-adjusted
after 100 time slots
![Page 21: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/21.jpg)
Simulation
![Page 22: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/22.jpg)
Simulation
![Page 23: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/23.jpg)
Simulation
![Page 24: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/24.jpg)
Simulation
![Page 25: AN ADAPTIVE MAC PROTOCOL FOR WIRELESS SENSOR NETWORKS Wen-Hwa Liao, Hsiao-Hsien Wang, and Wan-Chi Wu…](https://reader035.vdocuments.net/reader035/viewer/2022062911/5a4d1c087f8b9ab0599f20bc/html5/thumbnails/25.jpg)
Conclusion AMAC
has good adaptation ability doesn’t need time synchronous