analysis and design of link metrics for quality routing in wireless multi-hop networks phd thesis...

Analysis and Design of Link Metrics for Quality Routing in Wireless Multi-hop Networks

PhD Thesis Defense byNadeem JAVAID

Dec 15, 2010

Thesis DirectorProf. Karim DJOUANI

Jury :Rapporteur B.J. VAN WYK Prof. Tshwane University of Technology - South Africa Rapporteur J. BEN-

OTHMANMDC (HDR), Université de Versailles - France

Examinateur K. BARKAOUI Prof. CNAM, Paris - FranceExaminateur O. BRUN Directeur de recherche, LAAS-CNRS, Toulouse -

France Dir. de thèse K. DJOUANI Prof. Université Paris Est – France

Outlineo Performance Evaluation of Routing Protocols- Mobility/Speed Analysis- Scalability Analysis

- Traffic Analysiso Modeling Routing Overhead of Reactive Protocolso Design Requirements for Routing Link Metricso Min Hop-counto ETX-based Metrics- Expected Transmission Count (ETX)- Expected Link Performance (ELP)- Expected Throughput (ETP)o New Link Metric IBETX


PhD Defense by Nadeem JAVAID, Dec 15, 2010

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Outline



o Performance Evaluation of Routing Protocols- Mobility/Speed Analysis- Scalability Analysis


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Routing Protocols for Wireless Networks

o Reactive protocols- Reactive protocols perform RD and RM- Take an action when request arrives- More suitable for mobile scenarios- AODV, DSR, DYMO

o Proactive protocols- Periodically exchange information- More scalable- More suitable for less dynamic networks- DSDV, FSR, OLSR



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Protocol

Performance

Reasons

AODV +++•Provides multiple timely routes in RT•Time association•LLR quickly repairs link

DSR ++•Multiple routes in RC •Promiscuous listening mode.•Highest speed and highest mobility, low convergence

DYMO +•Not suitable for highly dynamic scenarios•Absence of grat. RREPs •Absence of supplementary maintenance strategies

Reactive ProtocolsMobility/Speed/Scalability/Traffic Analyses



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Protocol

Performance

Reasons

DSDV +++•Delay advertisement for route stabilization (Periodic, Nghbr)•Keep data for route settling time •Periodic and triggers updates

OLSR ++•More suitable for static or less dynamic networks•MPR-redundancy provides convergence in high mobility •Periodic updates

FSR +•Suitable for mobile scenarios as compared to static scenarios •Graded-frequency mechanism

Proactive ProtocolsMobility/Speed Analysis



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Protocol

Performance

Reasons

OLSR +++•More density, more optimization through MPRs•Absence of trigger updates•Retransmission reduction through MPRs

FSR ++•Exchange link state messages by GF (<MPR)•Absence of trigger updates •Broadcasting messages only to neighbors; no flooding

DSDV + •Transmission of trigger updates utilize more bandwidth

Proactive ProtocolsScalability Analysis



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Protocol

Performance

Reasons

FSR +++•Exchange link state messages by GF •Absence of trigger updates •no flooding

OLSR ++ •Absence of trigger updates•Retransmission reduction by MPRs (better in dense)

DSDV + •Transmission of trigger updates utilize more bandwidth

Proactive ProtocolsTraffic Analysis



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Outline





o [Park06] define cost for routing overhead for reactive protocols;

o No evaluation for CE and CT,

o We define Energy Consumed per packet,

o We define Time Consumed per packet,

Modeling Routing Overhead-Motivation



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o [sal10] considered: - only RREQ;- modeled only RD- evaluated energy-cost

o We consider: - both RREQ, RREP and RERR

overheads- both RD and RM- evaluate both energy and time-cost

of RD and RM

Modeling Routing Overhead-Motivation



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o Flooding exchanges topological information in a networkoPlain flooding

- Each received packet is (re)transmittedoSuper flooding

- A packet is (re)transmitted, if it has a shorter path

oMPRs flooding- Only MPR nodes flood

oBlind flooding- Each packet is (re)transmitted for first time

Flooding



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ERS



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ERS

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Energy-cost for RDo Energy-cost for a single ring,

o We consider routing overhead for ERS,o Energy-cost for RD ,



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o AODV and DYMO

waiting_time = 2 × NODE_TRAVERSAL_TIME ×(TTL_VALUE + TIME_OUT_BUFFER)

o For DSR- τ = 30ms - For TTL=TTL x 2, τ= τ x 2

Time-cost for RD



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Route maintenance



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Route maintenanceo S establishes path to D



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Route maintenanceo S establishes path to Do AODV and DYMO use

HELLO messages to check connectivity

o DSR uses link level feed-back



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o Node 7 detects link break



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o Node 7 detects link breako AODV starts LLRo LLR repairs the broken

linkso Reduces chance of route

re-discoveryo More suitable in large

networksAnalysis and Design of Link Metrics for Quality Routing in Wireless Multi-hop Networks


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Local Link Repairo S establishes path to Do AODV and DYMO use






networksAnalysis and Design of Link Metrics for Quality Routing in Wireless Multi-hop Networks


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o S establishes path to Do AODV and DYMO use






networks

Local Link Repair



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RERR in reactive protocolsAODVo If LLR fails then send

RERR messages to neighbors

o A RERR message is broadcasted (if there are many precursors)

o Or unicasted (if there is only 1 precursor)

o a node send upto RERR_RATELIMIT (=10) RERR messages per second



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RERR in reactive protocolsDSRo Success of PSo Node returns a RERR to

sender of packeto Then salvages packeto Node 7 is the

originating node for RERR



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RERR in reactive protocolsDYMOo Broadcast RERR

messages at link failureo MsgHdr.HopLimit is to

NET_DIAMETER (=10)o MsgHdr.HopCnt is set

to one



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Re-RD in reactive protocolsAODV (LLR)o RREQ_RETRIES = 2 to

start new RDDSR (PS)o Source piggy-backs

RERR with new RREQo Initiating RREQ based

on MaxMainRexmt=2DYMOo Decision based on

RREQ_TRIES =3 in DYMO to start new RD



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Energy-cost of RMAODV

DSR

DYMO



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AODV

DSR

DYMO

Time cost for RM



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Outline





Routing Link Metric oTo have appreciable performance from a

wireless network, a routing protocol (RP) plays an important role

oKey component of a RP is link metric (LM)oLM helps a RP first to find all possible

end-to-end paths and then selects the fastest path



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Routing Link Metric oMinimum Hop-count (Min-HC) is the most

popular and IETF standard metric and is appropriately used by wireless RP’s

oMin-HC rapidly finds new paths; where quality paths could not be found in due time due to higher rates of node mobility

oMin-HC is the simplest to calculate, as it avoids any computational burden on RP



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Designing a routing metricoMinimum-hop pathoBalancing traffic loadoMinimizing delayoMaximizing data delivery/aggregating

bandwidthoMinimizing energy consumptionsoMinimizing channel/interface switching



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Designing a routing metricoMinimizing interferenceoMaximizing route stabilityoMaximizing fault tolerance/minimizing

route sensitivityoAvoiding short and long lived loopsoConsidering performance trade-offsoMinimizing the Computational

overhead



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Computational Overhead



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Throughput

MD



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Throughput

ETX

MD



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Throughput

MD

ETXML



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Throughput

MD

ETXMLInvETX



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Plane Flooding



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MPR Flooding



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OLSR-ETX/InvETX/ML



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OLSR-MD



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End-to-end Delay

MD



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End-to-end Delay

ETX

MD



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End-to-end Delay

InvETXETX

MD



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End-to-end Delay

MD

ETXInvETXML



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Outline





ETX-based Metrics

Issues Solution

Links have different characteristics

Link asymmetry

Low bit-rate links effect faster links

Bandwidth

Congestion and Collisions Interference



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Issue(s) not considered Link metricInterference ETT, DBETX, EETT, EstdTT, MCR,

METX, ETPBandwidth ELP, WCETT, MIC, iAWARE,

EDR, ETX DistLink asymmetry MTM

Bandwidth and Interference ETX, mETX and ENT Link asymmetry

+Bandwidth

+Interference

No Metric yet

ETX-based Metrics



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Min Hop-count



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ETX



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ETX-based Metrics - ELP



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ETX-based Metrics - ETP



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Outline





IBETX - Motivationo In a WMN-backbone, either stationary or

minimally mobile nodes are interconnected

oThus, WMNs demand low end-to-end delay and high throughput paths from its operating RP

oSo, RP must choose a Quality LM to select the quality links



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IBETX - Motivation



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IBETX - Motivation



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IBETX - Motivation



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IBETX - Motivation



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IBETX



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IBETX

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Simulation parametersParameters ValuesNS version NS 2.34Protocol DSDVLink metrics ETX, ELP, ETP, IBETXNetwork area 1000m x 1000mNumber of nodes 50Source-destination pairs 20CBR packet size 640BytesData traffic rates 2pack/s to 10pack/sTopologies Mean of 5 random topologies is

usedTotal simulation time 900s



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Simulations-Throughput

ETX



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ETX

ELP




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ETX

ELP

ETP




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ETX

ELP

ETPIBETX




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ETX

ELP

ETPIBETX 10%




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ETX

ELP

ETP

10%

10%IBETX




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ETX

ELP

ETP

19%

10%

10%

IBETX




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Simulations-End-to-end Delay

ETX



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ETXELP




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ETXELP

ETP




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ETXELP

ETPIBETX




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ETXELP

ETPIBETX

15%




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ETXELP

ETP

16%

IBETX15%




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ETXELP

ETP

16%

IBETX15%

24%




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Conclusiono Performance Evaluation and Comparison of:

- 3 reactive protocols- 3 proactive protocols

o Modeling cost paid by reactive routing protocols for RD and RM in the form of time-spent and energy-consumed

o Performance study of ETX-based metrics

o Designing a Quality Link Metric and InvETX

o IBETX: Proposal and validationAnalysis and Design of Link Metrics for Quality Routing

in Wireless Multi-hop Networks PhD Defense by Nadeem JAVAID, Dec 15, 2010

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analysis and design of link metrics for quality routing in wireless multi-hop networks phd thesis...

Documents

routing link metrics

design of link metrics

quality routing

olsr analysis

outline analysis

new metric analysis

dynamic networks dsdv

dymo proactive protocols