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Performance Evaluation Of Mobile Ad Hoc NetworksKalyan KalepuMaster’s Thesis DefenseMay 6th 2004CommitteeDr. Chansu Yu Dr. Dan Simon Dr. Yongjian FuOutlineOutline�� IntroductionIntroduction�� Background on MANET Routing ProtocolsBackground on MANET Routing Protocols�� AODVAODV�� MotivationMotivation�� Issues addressed in this ThesisIssues addressed in this Thesis�� Experimental EvaluationExperimental Evaluation�� SimulationSimulation�� ConclusionConclusion

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IntroductionIntroductionAd Hoc NetworkingAd Hoc NetworkingMANETMANET��What is a What is a MANET MANET ??�� Mobile nodes, Wireless linksMobile nodes, Wireless links�� Infrastructure less: by the nodes…Infrastructure less: by the nodes…�� MultiMulti--hop routing: …for the nodeshop routing: …for the nodes�� Minimal administration: no hasslesMinimal administration: no hassles

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HQBackground on MANET Routing Background on MANET Routing ProtocolsProtocols�� Routing protocols for MANETs is Routing protocols for MANETs is divided into two typesdivided into two types�� Proactive routing protocol Proactive routing protocol –– Table drivenTable driven�� DSDVDSDV�� Reactive routing protocol Reactive routing protocol –– On demand On demand �� DSR, DSR, AODV AODV ( DSR+DSDV )( DSR+DSDV )

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Ad hoc OnAd hoc On--Demand Distance Demand Distance Vector (AODV)Vector (AODV)�� Initial design of AODV was undertaken to Initial design of AODV was undertaken to improve upon the deficiencies in DSDVimprove upon the deficiencies in DSDV�� AODV reduces the need for systemAODV reduces the need for system--wide wide broadcasts to counter the problems due to broadcasts to counter the problems due to the characteristics of wireless mediumthe characteristics of wireless medium�� AODV found it necessary to incorporate AODV found it necessary to incorporate the onthe on--demand route discovery and route demand route discovery and route maintenance mechanisms from DSR maintenance mechanisms from DSR Destination Sequenced Destination Sequenced Distance Vector (DSDV)Distance Vector (DSDV)�� DSDV is derived fromDSDV is derived from Distributed BellmanDistributed Bellman--FordFord (DBF) algorithm(DBF) algorithm�� DBF was designed for wired networks, so when DBF was designed for wired networks, so when used in wireless networks routing loops are used in wireless networks routing loops are formedformed�� Enhancements are made in DSDV to counter Enhancements are made in DSDV to counter looping problemlooping problem

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Contd…Contd… X YZFormation of Loops when DBF is used� X-Y-Z are connected in a triangle� X-Z link is highly unstable� If Y-Z link fails for a short period, it causes a routing loop Y-X-Y-ZContd…Contd…DSDV uses the sequence numbers to remove stale routes from the routing table of each node � S(X) and S(Y) are the destination sequence numbers stored at node X and node Y respectively � If S(X) < S(Y), node X does not update routes� If S(X) = S(Y), node X checks for lower metric� If S(X) < S(Y), node X updates accordingly

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Dynamic Source Routing (DSR)Dynamic Source Routing (DSR)S D�� OnOn--demand Route Discovery mechanismdemand Route Discovery mechanismAODVAODV�� Uses two mechanisms for routing Uses two mechanisms for routing �� Route DiscoveryRoute Discovery –– This mechanism is invoked when a source This mechanism is invoked when a source node has data to sendnode has data to send�� Route request (RREQ) Route request (RREQ) –– Broadcasts in search for a destinationBroadcasts in search for a destination�� Route reply (RREP) Route reply (RREP) –– Unicast packet by the Unicast packet by the destination/intermediate nodedestination/intermediate node� Route Maintenance – This mechanism responds to link failures�� Route error (RERR) Route error (RERR) –– Broadcast packet when a link failsBroadcast packet when a link fails

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Contd…Contd… DSHELLORREQRREPDATARERRMotivationMotivation�� In a In a Mobile Ad Hoc Network Mobile Ad Hoc Network (MANET), the (MANET), the surrounding physical environment is an surrounding physical environment is an important element to be considered for its important element to be considered for its deployment deployment �� It is necessary to evaluate MANET in real It is necessary to evaluate MANET in real world scenarios before actually using it in world scenarios before actually using it in the commercial worldthe commercial world

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Issues Addressed in this Issues Addressed in this ThesisThesis�� Comparing two MANET implementations Comparing two MANET implementations �� Comparing the performance of MANET in Comparing the performance of MANET in an indoor/outdoor environment an indoor/outdoor environment �� Key parameters in determining MANET Key parameters in determining MANET performance performance �� Differences between simulations and the Differences between simulations and the real worldreal world�� Analyzing the effects of interference in a Analyzing the effects of interference in a small MANET using simulation small MANET using simulation Experimental EvaluationExperimental Evaluation�� Survey of Existing AODV Survey of Existing AODV ImplementationsImplementations�� Experimental EnvironmentExperimental Environment�� Evaluation ToolEvaluation Tool�� Results & DiscussionResults & Discussion

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Survey of Exiting AODV Survey of Exiting AODV ImplementationsImplementations�� User space implementationUser space implementation�� MadMad--hoc, AODVhoc, AODV--UIUC, UIUC, AODVAODV--UUUU, , AODVAODV--UCSBUCSB�� Kernel space implementationKernel space implementation�� KernelKernel--AODVAODVContd.…Contd.…�� Kernel space implementationsKernel space implementations�� Less portableLess portable�� Weakens memory managementWeakens memory management�� AODVAODV--UU and AODVUU and AODV--UCSB were UCSB were chosenchosen

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Contd….Contd….�� AODVAODV--UU and AODVUU and AODV--UCSB are written in UCSB are written in Linux and CLinux and C�� Logical structure of both is the sameLogical structure of both is the same�� AODVAODV--UU supports UU supports unidirectionalunidirectional--link link avoidanceavoidanceExperimental EnvironmentExperimental Environment�� Experiments were conducted for Experiments were conducted for static and mobile scenarios in indoor static and mobile scenarios in indoor and outdoor environmentand outdoor environment�� Static scenario Static scenario -- varying packet sizesvarying packet sizes�� Mobile scenario Mobile scenario -- walking speed, fixed walking speed, fixed packet sizepacket size

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Outdoor EnvironmentOutdoor Environment

Indoor EnvironmentIndoor EnvironmentElectrical Engineering Dept.SH 309SH 309SH 309SH 309SH 309HallwaySH 309 Ladies RestroomMen RestroomECR Lab Mobile Communication Lab Communication Lab IEEE LoungeElevator Advanced Controls System

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Performance MetricsPerformance Metrics�� Throughput Throughput –– It is defined as the amount It is defined as the amount of data successfully delivered from the of data successfully delivered from the source to the destination in a given period source to the destination in a given period of time.of time.�� Response Time Response Time –– This is defined as the This is defined as the time required for a packet to travel from time required for a packet to travel from source to destination. source to destination. �� Block Size Block Size –– It is defined as the ratio of It is defined as the ratio of total size of each data packet transmitted total size of each data packet transmitted Evaluation ToolEvaluation Tool�� The following four graphs helps in The following four graphs helps in analyzing the MANET propertiesanalyzing the MANET properties�� Throughput GraphThroughput Graph�� Network Signature GraphNetwork Signature Graph�� Saturation GraphSaturation Graph�� Mobility GraphMobility Graph

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Network Connectivity TestNetwork Connectivity Test�� HelloHello�� Correct reception of neighboring HELLO messagesCorrect reception of neighboring HELLO messages�� Correct installation of route to neighboring nodeCorrect installation of route to neighboring node�� Deletion of route when nodes are disconnectedDeletion of route when nodes are disconnected�� 22--hop RREQ/RREPhop RREQ/RREP�� Node 1 issues a RREQ for node 3Node 1 issues a RREQ for node 3�� Node 2 receives the RREQ, and replies with a RREPNode 2 receives the RREQ, and replies with a RREP�� Node 1 receives the RREP, install the route, and pings are Node 1 receives the RREP, install the route, and pings are correctly receivedcorrectly received�� RERRRERR�� Node 2 issues a RERR for node 3 and removes its route to node Node 2 issues a RERR for node 3 and removes its route to node 33�� Node 1 receives this RERR, and removes its route to node 2 Node 1 receives this RERR, and removes its route to node 2 alsoalsoResults & DiscussionResults & Discussion�� Comparison of AODVComparison of AODV--UU and AODVUU and AODV--UCSBUCSB�� Implemented a static scenario in Indoor Implemented a static scenario in Indoor and Outdoor environment to study the and Outdoor environment to study the effect of unidirectional linkseffect of unidirectional links�� Implemented mobile scenario to Implemented mobile scenario to compare route discovery timecompare route discovery time

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Throughput Graph (Outdoor)Throughput Graph (Outdoor)

Throughput Graph (Indoor)Throughput Graph (Indoor)

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Network Signature Graph Network Signature Graph (Indoor)(Indoor)

Saturation Graph (Indoor)Saturation Graph (Indoor)

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Mobility Graph (Indoor)Mobility Graph (Indoor)1 2YX X, Y – Laptop 1 and Laptop 3 are two hops away1, 2 – Laptop 1 and Laptop 3 are one hop away

Contd…Contd…�� Comparison of Indoor and Outdoor Comparison of Indoor and Outdoor environment using AODVenvironment using AODV--UUUU•• Study the effect of external environment Study the effect of external environment on the performance of AODVon the performance of AODV--UUUU•• AODVAODV--UU was tested for static scenario in UU was tested for static scenario in indoor and outdoor environmentindoor and outdoor environment

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Throughput Graph (AODVThroughput Graph (AODV--UU)UU)

Signature Graph (AODVSignature Graph (AODV--UU)UU)

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Saturation Graph (AODVSaturation Graph (AODV--UU)UU)

SimulationSimulation�� Simulation Tool used is Simulation Tool used is nsns--22�� Assess the credibility of the simulator Assess the credibility of the simulator by comparing simulation results with by comparing simulation results with experimental results for mobile experimental results for mobile scenarioscenario�� Study the effect of interference in small Study the effect of interference in small MANETsMANETs

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Simulation ParametersSimulation ParametersIEEE 802.11MAC protocol

AODVRouting protocolRouting and MAC Protocols

5 nodes in an area 1000 x 1000mNumber of nodes and network area

300 secondsSimulation timeSimulation Parameters

0 m/s – 5 m/s (walking speed)Node speedMobility Pattern

Varying Packet size

Constant bit rateTraffic typeCommunication Model

1 MbpsWireless bandwidth

250 metersTransmission rangeRadio Characteristics

ValuesParameters

Assess the credibility of the Assess the credibility of the simulatorsimulator

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Experimental ScenarioExperimental ScenarioElectrical Engineering Dept.SH 309SH 309SH 309SH 309SH 309HallwaySH 309 Ladies RestroomMen RestroomECR Lab Mobile Communication Lab Communication Lab IEEE LoungeElevator Advanced Controls SystemThroughput GraphThroughput Graph

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Study the effects of Study the effects of Interference on MANETInterference on MANET�� Mobility Scenario with Interference Traffic Pattern 1Mobility Scenario with Interference Traffic Pattern 1Contd…Contd…�� Mobility Scenario with Interference Traffic Pattern 2Mobility Scenario with Interference Traffic Pattern 2

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Throughput GraphThroughput Graph

Delay Analysis GraphDelay Analysis Graph

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ConclusionsConclusions�� The effect of unidirectional links on The effect of unidirectional links on MANETs performance is quite considerable MANETs performance is quite considerable and cannot be ignored. and cannot be ignored. �� The performance of MANET can be The performance of MANET can be improved in indoor/outdoor environment, improved in indoor/outdoor environment, by finding the critical zonesby finding the critical zones�� Strong correlation between the parametric Strong correlation between the parametric values obtained by simulation and values obtained by simulation and experimental resultsexperimental results�� As the Interference traffic increases the As the Interference traffic increases the performance of the protocol degrades performance of the protocol degrades proportionally (linearly)proportionally (linearly)