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Efficient Flooding Scheme Based on 2-Hop Backward Information in Ad Hoc Networks

Trong Duc Le and Hyunseung ChooSchool of Information and Communication Engineering

Sungkyunkwan University, KoreaICC 2008

Speaker : Zhi-Han Lin

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Outline

Introduction Flooding scheme using 1-Hop Information

(1HI) Flooding scheme using 2-Hop Backward

Information (2HBI) Performance Evaluation Conclusion

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Introduction

Flooding is a basic operation to propagate control messages in most ad hoc routing protocols.

Pure flooding causes severe redundant transmissions, congestions of the wireless media, and collisions in networks.

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Flooding scheme using 1-Hop Information (1HI)

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Each node maintains the 1-hop neighbor information to locally optimize the number of RNs at the next hop.

The number of RNs (retransmitting nodes) is still relatively high.

The RNs are densely distributed along the network border.

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Distribution of retransmitting nodes in 1HI

Nodes:1000

Radio range:250m

Size:1000m*1000m

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Flooding scheme using 2-Hop Backward Information (2HBI)

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Distribution of retransmitting nodes in 2HBI

Nodes:1000

Radio range:250m

Size:1000m*1000m

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Performance Evaluation

By using the ns-2 simulator. Compare the pure flooding, Edge Forwarding,

CDS-based flooding and 1HI with 2HBI. Evaluate the performance of the ‘ratio of retr

ansmissions’ and ‘the number of collisions’.

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Nodes:200~1000

transmission range:250m

Size:1000m*1000m

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Nodes:500transmission range:100~300mSize:1000m*1000m

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Conclusion

The proposed scheme achieves its aim of minimizing the number of RNs and collisions in the network while maintaining the high deliverability of the flooding message.

The proposed scheme is suitable for its application to other ad hoc protocols in order to achieve a better flooding performance.