Kontextbewutes und interaktives Routing Experimentelle Anwendung und Ergebnisse

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Kontextbewußtes und interaktives
RoutingExperimentelle Anwendung und Ergebnisse

• Sven Hanemann, Matthew Smith and Bernd Freisleben
• Department of Mathematics and Computer Science
• University of Marburg, Germany
• hanemann/matthew/freisleb
• _at_informatik.uni-marburg.de

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Contents

• Published Results 2003
• Recent Results
• Cross-Layer Adaptivity (Reminder)
• Scenario
• Evaluation Environment
• Routing-Layer Aware Application
• Experimental Results
• Conclusions

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Published Results 2003

• Proactive Distance-Vector Multipath Routing for
• Wireless Ad Hoc Networks
• (Proceedings of IASTED International
  Conference
• Communication Systems and Networks (CSN
  2003),
• Result Load distribution, Reduced Link
  average link break
• time

• Update Message Delay An Approach for Improving
• Distance Vector Routing in Wireless Ad Hoc
• Networks
• (Proceedings of IEEE Symposium on
  Communications and Vehicular Technology
  (SCVT 2003),
• Result Routing message reduction up to 15

• Reducing Packet Transmission in Ad Hoc Routing
• Protocols by Adaptive Neighbor Discovery
• (Proceedings of the International Conference
  on
• Wireless Networks 2003 (ICWN03)
• Result Constant mean error rate by dynamic
  adaptation

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Recent Results Cross-Layer Adaptivity
Direction Routing-layer aware application
-gt Routing-triggered application

• Mobility
• Mobility does not solely happen to a network!
• Network information influences mobility decisions!

• Experiment
• Java application
• Real Linux systems
• Topology control for
• network preservation

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Scenario

• Mineclearing
• 4 Searcher Robots
• 1 Clearing Robot
• Sensor Laser Scanner
• 2 Minefields
• Range limited comms.

Shadow Deminer The Shadow Robot Company
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Player / Stage

• Player
• Player provides a network interface for a variety
  of robot and sensor hardware
• Multi language support
• Stage
• Stage simulates a population of mobile robots
  moving within two dimensional environment
• Stage is designed to simulate a large number of
  robots at low fidelity.

Stage Hospital
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User Mode Linux

• Real Linux
• Real Network
• Real Robot
• Control Interface

• UML Testbed for the ad hoc network

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Architecture Overview
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Routing-Layer Aware Application
Goal Keep the network intact while at the same
time allowing maximum freedom to execute primary
task! Solution Cross-layer active and passive
network preservation algorithms.
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Routing-Layer Aware Application
Passive Network Preservation

• Network Preservation Criteria
• Distance to neighbours
• Direction of travel of neighbours
• Own position
• Destination

• Passive Network Preservation
• does not interfere with active
• tasks!

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Routing-Layer Aware Application
Passive Network Preservation does not guarantee
network integrity!
Active Preservation

• Network Preservation Criteria
• Last know position of
  neighbours
• Last known direction of travel of neighbours
• Last known destination of neighbours

• Passive Preservation runs as non-interfering
  background task.

• Active Network Preservation
• overrides active tasks!

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Active Network Preservation

• Node 1 leaves network
• Cache last known position of neighbours
• Cache last known direction of travel of
  neighbours
• Cache last known destination of neighbours

• Active Network Preservation
• overrides active tasks! Outset
  Active Preservation is inactive!

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Video

• Demonstration of Active/Passive Network
  Preservation algorithm as an example for
  cross-layer applications

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Conclusions

• Active and Passive Network Preservation
  Algorithms based on
• cross-layer adaptation offer
• Ability to self heal broken network links
• Improved coverage of network space
• Connection reliability in sparse networks

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Future Work
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Questions?

• Thank you for your attention!
• Any Questions?

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Update Message Delay An Approach for Improving
Distance Vector Routing in Wireless Ad Hoc
Networks

• Aim
• Improving bandwidth and energy consumption by
  reducing
• unnecessary updates
• Benefits
• Routing message reduction up to 15

Number of required messages (180 meters
transmission range)
Reachable destinations (180 meters
transmission range)
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Proactive Distance-Vector Multipath Routing for
Wireless Ad Hoc Networks

• Aim
• Equip proactive routing with the capability of
  using multiple paths to each target by using
  already available topology information
• Benefits
• Load distribution, bottleneck avoidance, fairness
  and
• less communication breaks

Ohne Mehrwege
Mit Mehrwege
TERA mit Mehrwege TERA ohne Mehrwege
Last in
Last in
Communication breakdown length sec
Gitterhöhe
Gitterhöhe
Gitterbreite
Gitterbreite
Movement speed in m/s
Without multipath
With multipath
Improved average link breakage duration
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Reducing Packet Transmission in Ad Hoc Routing
Protocols by Adaptive Neighbor Discovery (1)

• Aim
• Minimize bandwidth consumption according to user
  requirements by adjusting neighbor detection
  accuracy
• Benefits
• Constant average error
• rate by dynamic adaptation
• Adaptive neighbor detection
• algoritm
• Maximal service availability with
• minimal bandwidth consumption

Scheme of a single node
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Reducing Packet Transmission in Ad Hoc Routing
Protocols by Adaptive Neighbor Discovery (2)

• Constant average error rate by dynamic
  adaptation

Bandwidth consumption with constant average error
rate
Evaluation of algorithm behavior