The Mobile and Pervasive Computing GroupElectrical and Computer Engineering

The University of Texas at Austin

Automated Routing Protocol Selection in Mobile Ad Hoc Networks

Taesoo Jun and Christine Julien March 13, 2007

Presented by Taesoo Jun

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Outline

Challenges and Goal

Motivating Scenarios

Protocol Selection Process

Conclusion

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Challenges

Challenges of Mobile Network Deployers• Multitude of choices for communication protocols

−Different characteristics dependent on operational environment

• Various applications and goals to be achieved−Different application requirements

Consideration of operational environment and application requirements

⇒⇒Select the most appropriate protocol for a Select the most appropriate protocol for a particular situationparticular situation

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Goal

Create an Automated Design Tool• Takes user input

−Physical characteristics of network: mobility degree, node density, etc.

−Characteristics of application: traffic rate, application goal, etc.

• Recommends the most appropriate protocol−Based on quantitative evaluation of candidate protocols

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Motivating Scenarios

Disaster Recovery• Destroyed infrastructure• EMT, police moving with

various tasks

Conference• Temporary meeting• Moving presenter, stationary

attendee with data sharing application

Solution•• Mobile Ad Hoc NetworkMobile Ad Hoc Network

Which routing protocol is Which routing protocol is best for each situation ?best for each situation ?

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Protocol Selection Process: Overview

Pre-design Time Processes• Simulation / Measurement• Behavior Extraction

Design Time Processes• Requirement Analysis• Evaluation

Input• Environmental Information• Application Requirement

Output• Recommended Routing

Protocol

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Protocol Selection ProcessPre-design Time

Simulation/MeasurementSimulation/Measurement• Gather information about performance

characteristics of candidate protocols• Affected by parameters

−Topological parameters• Influence of node movement in a topology: mobility

model• e.g., Random Waypoint Mobility Model (pause time,

max. speed, node density)−Traffic parameters

• Effect of varying data traffic• e.g., avg. payload size, data sending rate, src. density

• Simulate extensively over parameters• Provide the tool with the results as DB of

input

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Protocol Selection ProcessPre-design Time

Behavior ExtractionBehavior Extraction• Estimate generalized tendency for protocol

performance• Abstract the results of simulation/experiment

−Least square data fitting method

• Protocol behavior model−Analytic model on protocols’ performance

metrics over various parameters−Present in tool before design time

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3 Performance Metrics over 2 Parameters• End-to-end delay, Throughput,

Packet delivery ratio• # of traffic sources, pause time with

RWP mobility modelMultiple Regression on Simulation Results

Prototype Protocol Behavior ModelPre-design Time

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Protocol Behavior Model in the Scenariopre-design time

Multiple Regression Result

e.g.,

Analytic Model• Estimate a protocol’s performance with given parameters

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41037262 1037.11049.21046.11078.2 pppp ⋅⋅−⋅⋅+⋅⋅−⋅⋅+ −−−−

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Protocol Selection ProcessDesign Time

Requirement AnalysisRequirement Analysis• Takes inputs

−Environmental information: description of target environment−Application requirements: conditions for achieving application’s goal

• Generates outputs−Environmental parameters: operational parameters, traffic

parameters, mobility model type, node movement parameters−Performance metric requirements: quantity of performance metrics

with minimum or maximum−Priority information: relative priority on application

and performance metric• Maps or interprets

−Mapping or Interpretation of inputs to pertinent parameters

• Effective interface required

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Scenario RequirementsDesign Time

Disaster Recovery ScenarioEnvironmental Information• 50 first responders following the random waypoint model• Communication with each other maintaining 20 connections

Application Requirements• 4 applications operated in the network

− Voice communications: codec for voice−Command dispatch: highest priority, delivery guarantee− Location information exchange: lowest priority among applications− Snapshot transfer: lowest priority on delay

Other Information• 512 bytes UDP packet

Candidate Protocols• Reactive: DSR, AODV• Proactive: DSDV

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Scenario Protocol SelectionDesign Time

Environmental Parameters• # of mobile hosts: 50• Traffic type: Constant Bit Rate• Packet size: 512 bytes• # of traffic sources: 20• Movement model: Random

Waypoint Model• Mobile hosts Max. speed: 1 m/s• Pause time: 100 ms

Performance Metric Requirements

Priority Information

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Protocol Selection ProcessDesign Time

EvaluationEvaluation• Determine the most appropriate protocol• Compare expected performance of each protocol

1) Look up protocol behavior model with parameters2) Translate application requirement into preference values

Preference value: normalized deviation between simulated performance and given performance requirement

3) Combine the priority of performance metrics for each application

4) Combine the priority of applications for each protocol

5) Calculate total sum of weighted preference values

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Scenario Protocol SelectionDesign Time

Evaluation Result• Recommended protocol for disaster

recovery scenario: AODVAODV

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Conclusion

Novel design tool to support a mobile application deployerSelection of the most appropriate routing protocol for a target deploymentProtocol behavior model with several parameters given by userFuture work• Rapid Deployment of MANET applications

−Analytical protocol behavior model• Free from time-consuming simulations

−Effective requirement description• Efficient combination of requirements with protocol behavior model

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Questions?Questions?

E-mail: hopelist@mail.utexas.eduMPC URL: http://MPC URL: http://mpc.ece.utexas.edumpc.ece.utexas.edu

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Simulation Environment

Simulation• Ns-2 ver. 2.29• 10 times for each setting

Parameters

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Meaning• Analytical capture of S/W designer’s concern about protocol characteristics under an

environmentInput

• Operational environment information: topological parameters• Traffic information: traffic parameters

Output• Protocol characteristics: performance metrics

Method• Empirical study followed by regression method• Analytical analysis of protocols

Protocol Behavior ModelPre-design Time

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Protocol Behavior Model in the Scenario

AODV behavior model over pausetime, # of traffic sources

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Protocol Behavior Model in the Scenario

DSR behavior model over pausetime, # of traffic sources

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Protocol Behavior Model in the Scenario

DSDV behavior model over pausetime, # of traffic sources

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Protocol Selection ProcessDesign Time

EvaluationEvaluation• Determine the most

appropriate protocol• Compare expected

performance with application requirements−Preference value: how

favorable w.r.t. performance metrics

−Preference value table−Weighed sum for j-th

application with k-th protocol−Total sum for the system with k-th protocol