Ad Hoc Network 2

7/26/2019 Ad Hoc Network 2

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MOBILE AD HOC NETWORK

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PreparedBy :


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INTRODUCTION

.Since 1970s wireless network become popular as it

A mobie adhoc network is a infrastructure less network

allows us to communicate emergency search & rescue

operations.

here are currently ! "ariations of mobile network

#nfrastructured network.

#nfrastructure less network.

#t is one pf the most "ibrant & acti"e $new% fields today is

that of adhoc network

enables mobility.

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efinition'( An ad(hoc mobile network is a collection of mobile nodes that are dynamically and arbitrarily located in such a

manner that the interconnections between nodes are capable of

changing on a continual basis.

)A*+s are self(forming, self(maintained, and self(healing, allowing for e-treme network fle-ibility

A )A*+ consists of mobile platforms e.g., a router withmultiple hosts and wireless communications de"ices/ knownasnodes((which are free to mo"e about arbitrarily.

MANET


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ARCHITECTURE OF MANET

#t differs from traditional centrali2ed wireless networkas )A*+ has

*o centrali2ed control.

*odes itself has to pro"ide routing and )A3 layers functions.

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CHARACTERISTICS OF MANETS

ynamic topologies.

5andwidth(constrained, "ariable capacity links.

+nergy(constrained operation.

6imited physical security.

#(6ayer )obile 8outing .

)A*+ 8outing rotocol erformance #ssues.


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MANET ROUTING PROTOCOLS

he following is a list of :uantitati"e metrics that can be used to assess the performance

of any routing protocol.

+nd(to(end data throughput and delay.8oute Ac:uisition ime.+fficiency.

;actors affecting efficiency of a protocol'

A"erage number of data bits transmitted


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PERFORMANCE MEASURE OF MANET PROTOCOL

he following factors measure the performance of a protocol. *etwork si2e. opological rate of change. 6ink capacity. ;raction of unidirectional links. *etwork connecti"ity. raffic patterns. )obility.

;raction and fre:uency of sleeping nodes.

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DESIRABLE QUALITATIVE PROPERTIES OF

MANET ROUTING PROTOCOLS.

he desirable :ualitati"e properties of )A*+ routingprotocols are gi"en below.

istributed operation. 6oop(freedom. emand(based operation. Security.

Sleep period operation. >nidirectional link support.

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CATEGORIZATION OF AD-HOC ROUTING PROTOC

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DESTINATION-SEQUENCED DISTANCE- VECTOR

ROUTING (DSDV)

@ere +"ery mobile node in the network maintains a routingtable.

able contains'(

All of the possible destinations within the network. he number of hops to each destination are recorded. +ach entry is marked with a se:uence number assigned

by the destination node.

>pdate table can be sent in ! ways;ull dump.#ncremental update.

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CLUSTERHEAD GATEWAY SWITCH ROUTING(CGSR)

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THE WIRELESS ROUTING PROTOCOL (WRP)

he ireless 8outing rotocol 8/ is a table(basedprotocol with the goal of maintaining routing information

among all nodes in the network.

+ach node in the network is responsible for maintaining four tables'

8outing table.6ink(cost table.)essage retransmission list )86/ table.

istance table

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ADHOC ON-DEMAND DISTANCE VECTOR ROUTING

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DYNAMIC SOURCE ROUTING (DSR)

he protocol consists of two maBor phases'

8oute disco"ery and 8oute maintenance

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TEMPORALLY-ORDERED ROUTING ALGORITHM

;ig a/ ;oot creation showing link direction assignment/

b/8oute maintance showing link re"ersal phenomenon/ in C8A

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ASSOCIATIVITY-BASED ROUTING (ABR)

;ig(8oute )aintenance for Source and estination )o"ement

in A58.

1=


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SIGNAL STABILITY ROUTING (SSR)

SS8 selects routes based on the signal strength between nodes and on a nodeDs location stability.

his route selection criteria has the effect of choosing routesthat ha"e $stronger connecti"ities.

SS8 can be di"ided into two cooperati"e protocols' ynamic 8outing rotocol 8/ and Static 8outing rotocol S8/.

he 8 is responsible for the maintenance of

the Signal Stability able SS/ and the 8outingable 8/.

he S8 processes packets by looking up the destination inthe 8 and then forwards the packet.

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COMPARISON OF TABLE-DRIVEN PROTOCOLS

A8A)++8 DSDV CGSR WRP

Time Complexity (link

addition / failure)

O(d) O(d) O(h)

Communication Complexity

(link addition / failure)

O(xN) O(xN) O(xN)

!outin" #hilo$ophy %lat &ierarchical %lat

'oop %ree e$ e$ e$ *ut not

in$tantaneou$

Multica$t Capa*ility No No No

Num*er of !e+uired Ta*le$ T,o T,o %our

%re+uency of -pdate

Tran$mi$$ion$

#eriodically a$ needed

#eriodically #eriodically a$ needed

-pdate$ Tran$mitted to Nei"h*or$ Nei"h*or$ clu$ter head

Nei"h*or$

-tilie$ 0e+uence Num*er$ e$

e$

e$

-tilie$ 1&ello2 Me$$a"e$ e$

No e$

Critical Node$ No e$ (clu$ter head) No

!outin" Metric 0horte$t #ath

0horte$t #ath

0horte$t #ath

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COMPARISONS OF THE SOURCE-INITIATED ON-DEMAND

HOC ROUTING PROTOCOLS.erformance arameters

ACE S8 C8A A58 SS8

Time Complexity

(initialiation)

O(3d) O(3d) O(3d) O(d4) O(d4)

Time Complexity

(po$t failure)

O(3d) O(3d) or

5(cache hit)

O(3d) O(l4) O(l4)

Communication Complexity

(initialiation)

O(3N) O(3N) O(3N) O(N4y) O(N4y)

Communication Complexity(po$t failure)

O(3N) O(3N) O(3x) O(x4y) O(x4y)

!outin" #hilo$ophy %lat %lat %lat %lat %lat

'oop %ree e$ e$ e$ e$ e$

Multica$t Capa*ility e$ No No No No

6eaconin" !e+uirement$ No No No e$ e$

Multiple !oute #o$$i*ilitie$ No e$ e$ No No

!oute$ Maintained in routeta*le

route ta*le route ta*le route ta*le route ta*le

-tilie$ !oute Cache/Ta*le Expiration

Timer$

e$ No No No No

!oute !econfi"uration

Methodolo"y

Era$e !oute7

Notify

0ource

Era$e !oute7

Notify

0ource

'ink !e8er$al

!oute !epair

'ocalied 6roadca$t

9uery

Era$e !oute7

Notify

0ource

!outin" Metric %re$he$t

0horte$t #ath

0horte$t

#ath

0horte$t #ath A$$ociati8ity

0horte$t #ath

other$

A$$ociati8it

y

0ta*ility

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TABLE-DRIVEN VS ON-DEMAND ROUTING

arameters Cn(emand able(ri"en

A8aila*ility of !outin"

:nformation

A8aila*le

,hen needed

Al,ay$ a8aila*le re"ardle$$ of need

!outin"

#hilo$ophy

%lat

Mo$tly flat

except for C0;!

#eriodic route

update$

Not re+uired

e$

Copin" ,ith

mo*ility

-$in" localied route di$co8ery a$ in A6! and

00!

:nform other node$ to achie8e con$i$tent routin" ta*le

0i"nalin" traffic

"enerated

;ro,$ ,ith increa$in" mo*ility of acti8e

route$ (a$ in A6!)

;reater than that of on


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CONCLUSIONwireless networks can be deployed in either infrastructure(based mode or on an ad(hoc basis. Although work is being

done and prototype protocols are a"ailable for e-periments,

mobile ad(hoc networks still ha"e difficulties. hile some basic

network control functions and routing procedures ha"e beende"eloped, many

other issues re:uire attention. 8apidly changing topology,

network partitions, higher error rates, collision interference,

bandwidth constraints, and power limitations together pose

new challenges

in network controlF especially in the design of higher le"el

rotocols for routing and in implementing applications with

:uality of ser"ice re:uirements.

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@A*G > HHH

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Ad Hoc Network 2