Broadcast Scheduling in Broadcast Scheduling in Mobile Ad Hoc NetworksMobile Ad Hoc Networks

——Related work and our proposed approach

By Group 4: Yan Qiao, Yilin Shen, Bharat C. and Zheng Li

Presenter: Zheng Li

zhengli@ufl.edu

Existing broadcast Existing broadcast scheduling approaches for scheduling approaches for

MANETMANET

Blind floodingSelf/dominant pruningPDP and TDPForward-node-set-based

broadcast

Existing broadcast Existing broadcast scheduling approaches for scheduling approaches for

MANETMANET

Blind floodingSelf/dominant pruningPDP and TDPForward-node-set-based

broadcast

Existing broadcast Existing broadcast scheduling approaches for scheduling approaches for

MANETMANET

Blind floodingSelf/dominant pruningPDP and TDPForward-node-set-based

broadcast

Self Pruning and Dominant Self Pruning and Dominant PruningPruning

Optimal flooding tree (NP-C)Minimize the cost - the number of

transmissionsUtilize the neighborhood information

exchanged between nodesNodes keep reporting their

existence to neighbors

Reference:H. Lim and C. Kim, “Flooding in wireless ad hoc networks.”

Self PruningSelf Pruning

Dominant PruningDominant Pruning

Self Pruning and Dominant Self Pruning and Dominant PruningPruning

Weakness◦Overhead!!

“smart” routing more information needed increased overhead for transmission

Reference:H. Lim and C. Kim, “Flooding in wireless ad hoc networks.”

Existing broadcast Existing broadcast scheduling approaches for scheduling approaches for

MANETMANET

Blind floodingSelf/dominant pruningPDP and TDPForward-node-set-based

broadcast

Existing broadcast Existing broadcast scheduling approaches for scheduling approaches for

MANETMANET

Blind floodingSelf/dominant pruningTDP and PDPForward-node-set-based

broadcast

TDP and PDPTDP and PDP

Total/partial dominant pruningUtilized the neighborhood

information more effectivelyFurther reduced broadcast

redundancy

Reference:W. Lou and J. Wu“On Reducing Broadcast Redundancy in Ad Hoc Wireless Network”

TDP and PDPTDP and PDPWork well in the average case, but not

good in dense networksApproximation ratio O(n)Can be extended to a clustered

network A constant approximation ratio can be

achieved

Existing broadcast Existing broadcast scheduling approaches for scheduling approaches for

MANETMANET

Blind floodingSelf/dominant pruningPDP and TDPForward-node-set-based

broadcast

Forward-node-set-based Forward-node-set-based broadcastbroadcastProcess

◦ Clustering and one clusterhead for each cluster

◦ Transmit the message to the clusterhead◦ Clusterhead choose its forward-node-set to

reach the clusterheads within the range. Information of forward clusterheads and forward nodes piggybacked

◦ Nodes retransmit the message or do nothing

Reference:J. Wu and W. Lou“Forward-Node-Set-Based Broadcast in Clustered Mobile Ad Hoc Networks.”

Forward-node-set-based Forward-node-set-based broadcastbroadcast

Reference:J. Wu and W. Lou“Forward-Node-Set-Based Broadcast in Clustered Mobile Ad Hoc Networks.”

Forward-node-set-based Forward-node-set-based broadcastbroadcastConstant approximation ratioNumber of forward nodes relatively stableDense (all nodes) => sparse

(clusterheads)Heavy overhead

Forward-clusterhead-setForward-node-set

Clustering by group

Reference:J. Wu and W. Lou“Forward-Node-Set-Based Broadcast in Clustered Mobile Ad Hoc Networks.”

Existing broadcast Existing broadcast scheduling approaches for scheduling approaches for

MANETMANET

Blind floodingSelf/dominant pruningPDP and TDPForward-node-set-based

broadcast

Existing broadcast Existing broadcast scheduling approaches for scheduling approaches for

MANETMANET

Blind floodingSelf/dominant pruningPDP and TDPForward-node-set-based

broadcast

Broadcast scheduling in Broadcast scheduling in WSNWSNInterference-aware broadcastingHexagonal tilingColoringStatic WSN…

Reference:Ravi Tiwari, Thang N. Dinh, and My T. Thai“On Approximation Algorithms for Interference-Aware Broadcast Scheduling in 2D and 3D Wireless Sensor Networks.”

Our approachOur approachHexagonal tillingColoring to avoid interferenceDetails had been covered…Less assumptions, more realistic

◦Transmission/interference rangeLocal

◦Based on local information, group model

Compare with FNSB Compare with FNSB approachapproach

Overhead: ◦FNSB need to keep two lists◦Forward clusterheads and forward

nodesLatency:

◦FNSB selects the FNS every time

Thank you!Thank you!

Questions?Questions?