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Neighborhood Aware Power Saving Mechanisms for ad hoc networks

Abdelfettah Belghith1 , Wafa Akkari2

1.CRISTAL Laboratory, HANA Research Group University of Manouba, Tunisia2. CRISTAL Laboratory, HANA Research Group University of Manouba, Tunisia

IEEE Local Computer Networks, 2008. LCN 2008.

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Outline

Introduction Motivation Scheme

NA-PSM NTA-PSM

Simulation Conclusion

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Introduction

In PSM, nodes having traffic to transmit stay active during the whole beacon interval even after finish-ing the transmission and or the reception of all their traffic.

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Introduction

Increasing the Network Throughput Bounding the ATIM window

IPSM、 DPSM (single hop) DCS-PSM (multi hop)

Decreasing control packets NTA-PSM (proposing in this paper)

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Motivation

This paper reduces the control frames in ATIM window

Allowing the more traffic concurrency in ATIM window and increase the network throughput.

Enlarging Communication Window IPSM、 DPSM (single hop) DCS-PSM (multi hop)

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Before transmitting an ATIM frame It consults its Active Neighbor Table (ANT)

to see whether this destined node is already awake.

If YES , According to CSMA/CA If NO ,Send its own ATIM frame

Protocol_NA-PSM

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ATIMA B

C

C’s table

A B

Active Neighbor Table(ANT)

Temporary saved

Protocol_NA-PSM

When the node C negotiate in the ATIM window.

Destination addressSource address

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ATIM-ACKA B

C

C’s table

A B

Active Neighbor Table(ANT)

After a SIFS

Protocol_NA-PSM

When the node C negotiate in the ATIM window.

Destination address

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According to the CSMA/CA

Protocol_NA-PSM

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ATIMA BC

C’s table

A B

Active Neighbor Table(ANT)

Temporary saved

Protocol_NA-PSM

When the node C negotiate in the ATIM window.

Destination addressSource address

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ATIM-ACKA BC

C’s table

A B

Active Neighbor Table(ANT)

discardAfter a SIFS

Protocol_NA-PSM

When the node C negotiate in the ATIM window.

???

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Protocol_NA-PSM

(1) upon the start of a frame reception

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Protocol_NA-PSM

(2) upon the end of a frame reception

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Protocol_NA-PSM

(3) upon the end of a frame transmission

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Protocol_NA-PSM

(4) upon the start of a frame transmission

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Protocol_NA-PSM

(5) Before the beginning of the next Beacon interval

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Protocol_NA-PSM

(6) 1. upon the end of the ATIM window, if the station hasneither sent an ATIM frame nor an ATIM-ACK frame

2. no traffic to deliver to an already awake station(without sending an ATIM frame、 ATIM-ACK frame)

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TA-PSM To added a one bit MoreData field

If the MoreData bit is set in the received frame, both transmitting and receiving stations stay awake; otherwise, they can switch to the doze state.

NTA-PSM A node which sent an ATIM frame or an

ATIM-ACK couldn’t enter the doze state.

Protocol_NTA-PSM

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Simulation

simulator : Jsim Simulation run : 200 seconds CBR traffic models with different data rate Frame size : 512 byte Rate : 2Mbps Transmission range : 240 meter Beacon interval : 0.1 seconds ATIM window period : 0.001 s to 0.020 s Each of the eight flows to 50 packets per

second

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Aggregate throughput over all flows in the network: represents the total number of data frames delivered to all chosen destination stations at the end of the simulation.

Mean Sojourn Time: represents the average time a data frame spent in the network from its generation at the source station to its delivery to its ultimate destination station.

Simulation

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Power consumption: representing the total energy consumed by all stations during the simulation time.

Simulation

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Simulation

CH1→CH2, n1→CH1→CH2 →n7, n10→CH2→n6,n11→CH2→n5, n2→CH1→CH2→n8,n4→CH1→n11, n5→CH2→n8, n9→CH1→n3.

Example of a clustered ad hoc network

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Simulation

Aggregate Throughput over all flows versus ATIM window

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Simulation

802.11 PSMNA-PSM

Difference in Mean Sojourn Time versus ATIM window

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Simulation

Mean Sojourn Time versus ATIM window

Simulation

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Aggregate throughput over all flows versus traffic load

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Simulation

Mean Sojourn Time versus traffic load

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Conclusion

NTA-PSM inherits the exact functional context of PSM and thrives to enhance its behavior and efficiency by reducing the needed handshaking window.