Meshed Multipath Routing: An Efficient Strategy in Wireless Sensor Networks

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Meshed Multipath Routing An Efficient Strategy
in Wireless Sensor Networks
Swades DE Chunming QIAO Hongyi
WU EE Dept CSE Dept The
Center for Advanced Computer Studies State
Univ of New York at Buffalo Univ
of Louisiana at Lafayette Buffalo, NY
14260
Lafayette, LA 70504 swadesd,qiao_at_cse.buffalo.edu
wu_at_cacs.louisiana.edu
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Presentation Outline

• Introduction
• Motivation for improved routing
• Characteristics of meshed-multipath routing
• Performance studies
• Results
• Summary and conclusion

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Introduction

• Possible features of wireless sensor networks
• Multihop source-destination routes
• Limited or no mobility of nodes
• Nodes could be imparted with location info during
  deployment
• Small coverage range of a node 20 to 50 meters
• Could be unattended for lifetime
• High node density
• Large network size
• Required highly affordable cost of sensors

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Introduction (contd..)

• Possible features (contd.)
• Field applications may be associated with high
  ground wave absorption
• High interference from FCC allocated channel
  users (Likely to use UWB-based communication
  technology along with CDMA)
• Limited memory and processing power
• Limited battery resource
• Highly failure-prone nodes
• Robust and yet energy-efficient routing technique
  necessary

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Motivations for Improved Routing

• Existing multihop wireless routing techniques
• Packet replication (PR) along multiple routes
  (noted in Kulik99, Ganesan01)
• simple but could be energy-intensive
• Traffic splitting along multiple disjoint routes
  (D-MPR) Lee01,Tsirigos01
• End node controlled no routing flexibility at
  an intermediate stage
• The preferred (primary) route is used, secondary
  routes are kept standby Nasipuri99, Ganesan01
• Additional energy for route maintenance
• Little traffic load balancing may lead to
  quicker network partition
• End-to-end ACK/NACK Chen99, or adjacent node
  NACKGanesan01,Wan02, or promiscuous listening
  Johnson96 based retransmission
• Involved flow-control mechanism, additional
  buffer space, transmit/receive changeover delay,
  and receive power

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Motivations for Improved Routing (contd..)

• Existing multiple-path route searching techniques
• Multicast-tree based Chen99, Su99
• Sequential Ganesan01 additional delay and
  energy requirement

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Our Approach Meshed Multipath Routing (M-MPR)

• Main characteristics of M-MPR
• Uses meshed (non-disjoint) multiple paths
• Uses selective forwarding (SF), whereby a packet
  is forwarded to the best next hop, determined
  locally and dynamically
• Eliminates explicit need for secondary route
  maintenance
• Reduces the risk of making wrong routing
  decisions at the end node
• Multiple paths are utilized automatically
• Forward error correction (FEC) coding is used to
  reduce/ avoid re-transmission

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M-MPR (contd..)

• Meshed multipath searching (topology
  construction)
• Acquiring neighborhood information
• Uses location information
• Route discovery
• Meshed (instead of tree-based or sequential)
• Route reply
• Returns the ACK along the mesh (reverse
  direction)
• Each active node is responsible for maintaining
  connectivity in the mesh

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M-MPR (contd..)
A source-to-destination meshed route
Meshed topology formed by many-sources-to-a-desti
nation routes
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M-MPR vs. D-MPR Throughput Analysis
Idealized meshed routes

• Other assumptions
• All nodes have equiprobable failure rate,
• All links (AWGN channel) have equiprobable
  failure rate,

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Performance Results

• Simulation parameters
• 500 nodes randomly uniformly distributed in 500 m
  sq. area
• Coverage range of each node 40 m
• SNR at the receiver 14 dB
• Fixed packet size 50 Byte

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Performance Results M-MPR vs. D-MPR
Throughput plot Analysis (6-hop route)
Throughput plot Simulation (avg. hop length
9.06)
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Performance Results M-MPR vs. D-MPR (contd..)

• Throughput gain vs. route length (with respect to
  D-MPR)

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Performance Results M-MPR vs. Preferred routing

• M-MPR (M-MPR-SF)
• A packet forwarding node is selected dynamically
• In case of equally good options, one is chosen by
  flipping a fair coin
• Preferred routing (Primary/secondary routes)
• A packet forwarding node is pre-decided (primary
  route)
• In case of failure (NACK/promiscuous listening),
  an alternate node is selected

A simulated meshed multipath
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Performance Results M-MPR vs. Preferred routing
(contd..)
Load distribution along multipath packets
PLR1 - normalized thpt.
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Summary and Conclusion

• Meshed multipath routing provides improved
  throughput performance over disjoint multipath
  routing
• Selective forwarding along meshed multipath has
  better load balancing performance than using a
  preferred route
• Performance comparison of FEC based selective
  forwarding w.r.to packet replication is not
  studied here (will be presented in upcoming
  ICC03)

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• Thank you !