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Neighborhood Aware Power Saving Mechanisms for ad hoc networks. Abdelfettah Belghith 1 , Wafa Akkari 2 1.CRISTAL Laboratory, HANA Research Group University of Manouba , Tunisia 2. CRISTAL Laboratory, HANA Research Group University of Manouba , Tunisia.
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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, Tunisia 2. CRISTAL Laboratory, HANA Research Group University of Manouba, Tunisia IEEE Local Computer Networks, 2008. LCN 2008.
Outline • Introduction • Motivation • Scheme • NA-PSM • NTA-PSM • Simulation • Conclusion
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.
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)
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)
Protocol_NA-PSM • 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 Active Neighbor Table(ANT) Destination address Source address ATIM A B Temporary saved C When the node C negotiate in the ATIM window.
Protocol_NA-PSM Active Neighbor Table(ANT) Destination address ATIM-ACK A B After a SIFS C When the node C negotiate in the ATIM window.
Protocol_NA-PSM According to the CSMA/CA
Protocol_NA-PSM Active Neighbor Table(ANT) Destination address Source address ATIM C A B Temporary saved When the node C negotiate in the ATIM window.
Protocol_NA-PSM Active Neighbor Table(ANT) ATIM-ACK ??? C A B discard After a SIFS When the node C negotiate in the ATIM window.
Protocol_NA-PSM (1) upon the start of a frame reception
Protocol_NA-PSM (2) upon the end of a frame reception
Protocol_NA-PSM (3) upon the end of a frame transmission
Protocol_NA-PSM (4) upon the start of a frame transmission
Protocol_NA-PSM (5) Before the beginning of the next Beacon interval
Protocol_NA-PSM (6) 1. upon the end of the ATIM window, if the station has neither 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)
Protocol_NTA-PSM • 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.
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
Simulation • 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 • Power consumption: representing the total energy consumed by all stations during the simulation time.
Simulation Example of a clustered ad hoc network 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.
Simulation Aggregate Throughput over all flows versus ATIM window
Simulation Difference in Mean Sojourn Time versus ATIM window 802.11 PSM NA-PSM
Simulation Mean Sojourn Time versus ATIM window
Simulation Aggregate throughput over all flows versus traffic load
Simulation Mean Sojourn Time versus traffic load
Conclusion • NTA-PSM inherits the exact functional context of PSM and thrives to enhance its behavior and efficiency by reducing the needed handshaking window.