
2/345

REG* NUMBER ( )))))))))))))))))))))))))))))))))

SEMESTER ( )))))))))))))))))))))))))))))))))

+EAR ( )))))))))))))))))))))))))))))))))))


3/345

THIRUMALAI

ENGINEERING

COLLEGE

KILAMBI,

KANCHIPURAM-

631551

DEPARTMENT OF COMPUTER SCIENCE ANDENGINEERING

BONAFIDE CERTIFICATE

This is to certify that this is a

bonafide work done by

Mr./Miss.______________________________

Reg.No._____________________


4/345

For the CS 6&11 - Networ! L"#or"tor$ as a

part of B*E*, Co.ter S/0e/e "12

E1301eer013 course in T40r.,"5"0 E1301eer013

Co55e3e, Kanchipuram during the year of !""#!".

The Record is found to be comp$eted and satisfactory.

He"2 o t4e De"rtet

St"7 I-C4"re

%ubmitted for the &ractica$ '(amination he$d on))))))))))))))))

Iter" E8"0er

E8ter" E8"0er


5/345

E9*NO(1%"' Ieet"t0o o S020:02owProto/o

AIM(

To write a )a*a program to perform s$iding window protoco$

ALGORITHM(

".%tart the program.

.+et the frame sie from the user

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user reuest. .To send frames toser*er from the c$ient side.

0.1f your frames reach the ser*er it wi$$ send 23K signa$ to c$ient

otherwise it wi$$ send N23K signa$ toc$ient.

4.%top the program

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pub$ic static

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7/345

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pri

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9/345

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10/345

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RECEI;ER PROGRAM

import )a*a.net.56 import )a*a.io.56 c$ass s$idrecei*er7

pub$ic static

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11/345

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21/345

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22/345

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27/345

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28/345

ept

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-.%end its address to the ser*er.

.=isp$ay the date P time sent by the ser*er.

0.3$ose the input and output streams.

4.3$ose the c$ient socket.

. %top.

PROGRAM(

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43/345

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45/345

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46/345

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49/345

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53/345

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+MTD!0A-! !!>3AE&rogramFi$esESa*aE)dk".0.!Ebin

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55/345

E9*NO(3 :r0te " /o2e !0."t0 ARP


56/345

A0(

To write a )a*a program for simu$ating 2R& protoco$s using T3&

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Ser>er

". %tart the program. 2ccept the socket which is created by the c$ient.-. %er*er maintains the tab$e in which 1& and corresponding M23addresses are stored.. Read the 1& address which is send by the c$ient.0. Map the 1& address with its M23 address and return the M23 address toc$ient.

Pror"

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57/345

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60/345

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61/345

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78/345

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79/345

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84/345

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85/345

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91/345

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To Jrite the )a*a program for simu$ating ping command

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92/345

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93/345

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94/345

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95/345

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157/345

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172/345

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173/345

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174/345

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175/345

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176/345

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177/345

8;,!,p.getBength8;;6%ystem.out.print

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178/345

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200/345

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208/345

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To write a )a*a program for =N% app$ication

Aor0t4

".%tart the program.

.+et the frame sie from the user-.To create the frame based on the user reuest..To send frames to ser*er from the c$ient side.

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209/345

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214/345

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234/345

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237/345

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238/345

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269/345

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Most of the commercia$ simu$ators are +1 dri*en,

whi$e some network simu$ators are 3B1 dri*en. The network

mode$ / configuration describes the state of the network

8nodes,routers, switches, $inks; and the e*ents 8data

transmissions, packet error etc.;. 2n important output ofsimu$ations are the trace fi$es. Trace fi$es $og e*ery packet,

e*ery e*ent that occurred in the simu$ation and are used for

ana$ysis. Network simu$ators can a$so pro*ide other too$s to

faci$itate *isua$ ana$ysis of trends and potentia$ troub$e spots.

Most network simu$ators use discrete e*entsimu$ation, in which a $ist of pending @e*ents@ is stored, andthose e*ents are processed in order, with some e*entstriggering future e*ents_ such as the e*ent of the arri*a$ ofa packet at one node triggering the e*ent of the arri*a$ ofthat packet at a downstream node.

%imu$ation of networks is a *ery comp$e( task. Fore(amp$e, if congestion is high, then estimation of the

a*erage occupancy is cha$$enging because of high *ariance.To estimate the $ike$ihood of a buffer o*erf$ow in anetwork, the time reuired for an accurate answer can bee(treme$y $arge. %pecia$ied techniues such as @contro$

*ariates@ and @importance samp$ing@ ha*e been de*e$oped tospeed simu$ation.


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E8"e! o etwor !0."tor!There are many both free/open#source and

proprietary network simu$ators. '(amp$es of

notab$e network simu$ation software are, ordered after howoften they are mentioned in researchpapersA

". ns 8open source;. ?&N'T 8proprietary software;

-.Net%im 8proprietary software;

U!e! o etwor !0."tor!

Network simu$ators ser*e a *ariety of needs. 3ompared to

the cost and time in*o$*ed in settingup an entire test bed containing mu$tip$e networkedcomputers, routers and data $inks, networksimu$ators are re$ati*e$y fast and ine(pensi*e. They a$$owengineers, researchers to test scenariosthat might be particu$ar$y difficu$t or e(pensi*e to emu$ate

using rea$ hardware # for instance,

simu$ating a scenario with se*era$ nodes or e(perimenting

with a new protoco$ in the network.

Network simu$ators are particu$ar$y usefu$ in a$$owing

researchers to test new networking

protoco$s or changes to e(isting protoco$s in a contro$$edand reproducib$e en*ironment. 2

typica$ network simu$ator encompasses a wide range ofnetworking techno$ogies and can he$p theusers to bui$d comp$e( networks from basic bui$ding b$ockssuch as a *ariety of nodes and $inks.Jith the he$p of simu$ators, one can design hierarchica$networks using *arious types of nodes$ike computers, hubs, bridges, routers, switches, $inks, mobi$eunits etc.

Various types of Jide 2rea Network 8J2N; techno$ogies

$ike T3&, 2TM, 1& etc. and Boca$ 2rea Network 8B2N;techno$ogies $ike 'thernet, token rings etc., can a$$ be

simu$ated with a typica$ simu$ator and the user can test,ana$ye *arious standard resu$ts apart from de*ising someno*e$ protoco$ or strategy for routing etc. Networksimu$ators are a$so wide$y used to simu$ate batt$efie$dnetworks in Network#centric warfare


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There are a wide *ariety of network simu$ators, rangingfrom the *ery simp$e to the *ery comp$e(. Minima$$y, anetwork simu$ator must enab$e a user to represent a network

topo$ogy, specifying the nodes on the network, the $inks

between those nodes and the traffic between the nodes. Morecomp$icated systems may a$$ow the user to specifye*erything about the protoco$s used to hand$e traffic in anetwork. +raphica$ app$ications a$$ow users to easi$y*isua$ie the workings of their simu$ated en*ironment. Te(t#

based app$ications may pro*ide a $ess intuiti*e interface, butmay permit more ad*anced forms of customiation.

P"/et o!!

occurs when one or morepacketsof data tra*e$$ing across acomputer networkfai$ to reachtheirdestination. &acket $oss is distinguished as one of the three

main error types encountered indigita$ communications6 the other two being bit errorandspurious packets caused due to noise.

&ackets can be $ost in a network because they may bedropped when a ueue in the network nodeo*erf$ows. The amount of packet $oss during the steadystate is another important property of acongestion contro$ scheme. The $arger the *a$ue of packet$oss, the more difficu$t it is fortransport$ayer protoco$s to maintain high bandwidths, thesensiti*ity to $oss of indi*idua$ packets,as we$$ as to freuency and patterns of $oss among $onger

packet seuences is strong$y dependenton the app$ication itse$f.


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T4ro.4.t

This is the main performance measure characteristic, and most

wide$y used.1ncommunicationnetworks, such as'thernetorpacket radio, throughputornetwork throughputis

the a*erage rate of successfu$message de$i*ery o*er a

communication channe$. The throughput is usua$$y measured

inbitsper second 8bit/s orbps;, andsometimes indata

packetsper second or data packets pertime s$otThis measure

how soon the recei*er is ab$e to get a certain amount of data

send by the sender. 1t is determined as the ratio of the tota$

data recei*ed to the end to end de$ay. Throughput is an

important factor which direct$y impacts the network

performance

De"$

=e$ay is the time e$apsed whi$e a packet tra*e$s from one

point e.g., source premise or network

ingress to destination premise or network degrees. The $arger

the *a$ueof de$ay, the more difficu$t

it is for transport $ayer protoco$s to maintain highbandwidths.

Je wi$$ ca$cu$ate end to end de$ay

.e.e Let42 ueuing system in networks can be described as

packets arri*ing for ser*ice, waiting for ser*ice if it is notimmediate, and if ha*ing waited for ser*ice, $ea*ingthesystem after being ser*ed. Thus ueue $ength is *eryimportant characteristic to determine that how we$$ theacti*e ueue management of the congestion contro$a$gorithm has been working.


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11* Peror " /"!e !t.2$ "#o.t t4e 207eretro.t0 "or0t4! to !ee/t t4e


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etwor "t4 w0t4 0t! ot0. "2e/oo0/" 2.r0 2"t" tr"!er*

0* L0 St"te ro.t0

A0(To study the $ink state routing

L0 St"te ro.t0

Routing is the process of se$ecting best paths in a network. 1n

the past, the term routing was a$so used to mean forwarding

network traffic among networks. Howe*er this $atter

function is much better described as simp$y forwarding.

Routing is performed for many kinds of networks,inc$uding the te$ephone network 8circuit switching;,

e$ectronic data networks 8such as the 1nternet;, and

transportation networks. This artic$e is concerned

primari$y with routing in e$ectronic data networks using

packet switching techno$ogy.

1n packet switching networks, routing directs packet

forwarding 8the transit of $ogica$$y addressed

network packets from their source toward their u$timate

destination; through intermediate nodes.1ntermediate nodes are typica$$y network hardware de*ices

such as routers, bridges, gateways,

firewa$$s, or switches. +enera$#purpose computers can a$so

forward packets and perform routing,

though they are not specia$ied hardware and may suffer

from $imited performance. The routing

process usua$$y directs forwarding on the basis of routing

tab$es which maintain a record of the

routes to *arious network destinations. Thus, constructing

routing tab$es, which are he$d in therouterUs memory, is *ery important for efficient routing. Most

routing a$gorithms use on$y one

network path at a time. Mu$tipath routing techniues enab$e

the use of mu$tip$e a$ternati*e paths.


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1n case of o*er$apping/eua$ routes, the fo$$owing e$ementsare considered in order to decide which routes get insta$$edinto the routing tab$e 8sorted by priority;A

". Pre8-Le3t4A where $onger subnet masks are

preferred 8independent of whether it iswithin a routing protoco$ or o*er different routing

protoco$;

. Metr0/A where a $ower metric/cost is preferred 8on$y*a$id within one and the same routing

protoco$;

-. A200!tr"t0>e 20!t"/eA where a $ower distanceis preferred 8on$y *a$id between different

routing protoco$s;

Routing, in a more narrow sense of the term, is often

contrasted with bridging in its assumption that network

addresses are structured and that simi$ar addresses imp$y

pro(imity within the network. %tructured addresses a$$ow a

sing$e routing tab$e entry to represent the route to a group of

de*ices. 1n $arge networks, structured addressing 8routing, in

the narrow sense; outperforms unstructured addressing

8bridging;. Routing has become the dominant form of

addressing on the 1nternet. Iridging is sti$$ wide$y used

within $oca$ied en*ironments.


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00* Foo20

F5oo203 s a simp$e routing a$gorithm in which e*ery

incoming packet is sent through e*eryoutgoing $ink e(cept the one it arri*ed on.F$ooding is used

in bridging and in systems such as

senet and peer#to#peer fi$e sharing and as part of some

routing protoco$s, inc$uding ?%&F,

=VMR&, and those used in ad#hoc wire$ess networks.There

are genera$$y two types of f$ooding

a*ai$ab$e, ncontro$$ed F$ooding and 3ontro$$ed

F$ooding.ncontro$$ed F$ooding is the fata$ $aw

of f$ooding. 2$$ nodes ha*e neighbours and route packets

indefinite$y. More than two neighbourscreates a broadcast storm.

3ontro$$ed F$ooding has its own two a$gorithms to make it

re$iab$e, %N3F 8%euence Number

3ontro$$ed F$ooding; and R&F 8Re*erse &ath F$ooding;. 1n

%N3F, the node attaches its own

address and seuence number to the packet, since e*ery

node has a memory of addresses and

seuence numbers. 1f it recei*es a packet in memory, it

drops it immediate$y whi$e in R&F, thenode wi$$ on$y send the packet forward. 1f it is recei*ed from

the ne(t node, it sends it back to the

sender.

Aor0t4

There are se*era$ *ariants of f$ooding a$gorithm. Most work rough$y asfo$$owsA

".

'ach node acts as both a transmitter and a recei*er.

. 'ach node tries to forward e*ery message to e*ery oneof its neighbours e(cept the source

node.

This resu$ts in e*ery message e*entua$$y being de$i*ered to a$$ reachab$eparts of the network.


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2$gorithms may need to be more comp$e( than this, since, in

some case, precautions ha*e to be taken to a*oid wasted

dup$icate de$i*eries and infinite $oops, and to a$$ow messages

to e*entua$$y e(pire from the system. 2 *ariant of f$ooding

ca$$ed !ee/t0>e oo20partia$$y addresses these issues

by on$y sending packets to routers in the same direction. 1n

se$ecti*e f$ooding the routers donUt send e*ery incoming

packet on e*ery $ine but on$y on those $ines which are

going appro(imate$y in the right direction.

A2>"t"e!

f a packet can be de$i*ered, it wi$$ 8probab$y mu$tip$e times;.

shortest path.atura$$y uti$ies e*ery path through the network, it

wi$$ a$so use the

G This a$gorithm is *ery simp$e to imp$ement.


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D0!"2>"t"e!

F$ooding can be cost$y in terms of wasted bandwidth. Jhi$e amessage may on$y ha*e

one destination it has to be sent to e*ery host. 1n the caseof a ping f$oor a denia$ of ser*ice attack, it can be harmfu$to the re$iabi$ity of a computer network.

Messages can become dup$icated in the network further

increasing the $oad on thenetworks bandwidth as we$$s reuiring an increase in

processing comp$e(ity todisregard dup$icate messages.

=up$icate packets may circu$ate fore*er, un$ess certain precautions are takenA

se a hop count or a time to $i*e count and inc$ude it witheach packet. This *a$ue shou$d

take into account number of nodes that a packet may ha*eto pass through on the way

to its destination.

Ha*e each node keep track of e*ery packet seen and on$y forward each packet once

'nforce a network topo$ogy without $oops

000 * D0!t"/e >e/tor

1n computer communication theory re$ating to packet#switched

networks, a 20!t"/e->e/tor ro.t03 roto/o5 is one of the two ma)or c$asses

of routing protoco$s, the other ma)or

c$ass being the $ink#state protoco$. =istance#*ector routing

protoco$s use the Ie$$man#Ford

a$gorithm, Ford#Fu$kerson a$gorithm, or =2B F%M 8in the

case of 3isco %ystemsUs protoco$s;

to ca$cu$ate paths.

2 distance#*ector routing protoco$ reuires that a router

informs its neighbors of topo$ogy changes periodica$$y.3ompared to $ink#state protoco$s, which reuire a router to

inform a$$ the nodes in a network of topo$ogy changes,

distance#*ector routing protoco$s ha*e $ess

computationa$ comp$e(ity and message o*erhead.


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The term 20!t"/e >e/tor refers to the fact that theprotoco$ manipu$ates >e/tor! 8arrays; of distances toother nodes in the network. The *ector distance

a$gorithm was the origina$ 2R&2N'T routing a$gorithm

and was a$so used in the internet under the name of R1&

8Routing 1nformation &rotoco$;.

'(amp$es of distance#*ector routing protoco$s inc$ude R1&*" and R1&*and 1+R&.

Met4o2

Routers using distance#*ector protoco$ do not ha*eknow$edge of the entire path to a destination. 1nstead they usetwo methodsA

". =irection in which router or e(it interface a packet shou$d beforwarded.

. =istance from its destination

=istance#*ector protoco$s are based on ca$cu$ating thedirection and distance to any $ink in anetwork. @=irection@ usua$$y means the ne(t hop addressand the e(it interface. @=istance@ is a


280/345

measure of the cost to reach a certain node. The $east cost route

between any two nodes is the route with minimum distance. 'achnode maintains a *ector 8tab$e; of minimum distance to e*ery node.

The cost of reaching a destination is ca$cu$ated using *arious route

metrics. R1& uses the hop count of the destination whereas 1+R& takes

into account other information such as node de$ay and a*ai$ab$e

bandwidth.

pdates are performed periodica$$y in a distance#*ector protoco$ where

a$$ or part of a routerUs routing tab$e is sent to a$$ its neighbors that are

configured to use the same distance#*ector routing protoco$. R1&

supports cross#p$atform distance *ector routing whereas 1+R& is a3isco %ystems proprietary distance *ector routing protoco$. ?nce a

router has this information it is ab$e to amend its own routing tab$e to

ref$ect the changes and then inform its neighbors of the changes.

This process has been described as `routing by rumor because

routers are re$ying on the information they recei*e from other routers

and cannot determine if the information is actua$$y *a$id and true.

There are a number of features which can be used to he$p with

instabi$ity and inaccurate routing information.

'+& and I+& are not pure distance#*ector routing protoco$s because adistance#*ector protoco$ ca$cu$ates routes based on$y on $ink costs

whereas in I+&, for e(amp$e, the $oca$ route preference *a$ue takes

priority o*er the $ink cost.

Co.t-to-00t$ ro#e

The Ie$$man#Ford a$gorithm does not pre*ent routing $oops from

happening and suffers from the /o.t-

to-00t$ ro#5e. The core of the count#to#infinity prob$em

is that if 2 te$$s I that it has a pathsomewhere, there is no way for I to know if the path has I as a part

of it. To see the prob$em c$ear$y,

imagine a subnet connected $ike 2#I#3#=#'#F, and $et the metric

between the routers be @number of

)umps@. Now suppose that 2 is taken off$ine. 1n the *ector#update#

process I notices that the route to 2,


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which was distance ", is down # I does not recei*e the *ector update

from 2. The prob$em is, I a$so gets

an update from 3, and 3 is sti$$ not aware of the fact that 2 is down #

so it te$$s I that 2 is on$y two )umps

from 3 83 to I to 2;, which is fa$se. This s$ow$y propagates through

the network unti$ it reaches infinity

8in which case the a$gorithm corrects itse$f, due to the re$a(ation

property of Ie$$man#Ford;.

E8*o*11 UNICAST ROUTING PROTOCOL

2imATo write a ns program for imp$ementing unicast routing protoco$.


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2$gorithmA

%tep "A start the program.

%tep A dec$are the g$oba$*ariab$es ns for creating a newsimu$ator. %tep -A set the co$orfor packets.

%tep A open the network animator fi$e inthe name of fi$e in the write mode. %tep0A open the trace fi$e in the name of fi$e "in the write mode.

%tep 4A set the unicast routing protoco$ totransfer the packets in network. %tep Acreate the reuired no of nodes.%tep >A create the dup$e(#$ink between the nodes inc$uding thede$ay time,bandwidth and dropping

ueue mechanism.%tep OA gi*e the position for the $inks between the nodes.%tep "!A set a tcp reno connection for source node.%tep ""A set the destination node using tcp sink.%tep "A setup a ftp connection o*er the tcp connection.

%tep "-A down the connection

between any nodes at a particu$artime. %tep "A reconnect thedowned connection at aparticu$ar time.%tep "0A define the finishprocedure.%tep "4A in the definition of the finish proceduredec$are the g$oba$ *ariab$es ns,fi$e",fi$e. %tep "Ac$ose the trace fi$e and namefi$e and e(ecute thenetwork animation fi$e.

%tep ">A at the particu$ar time ca$$ the finish

procedure.%tep "OA stop the program.


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Pror"(set ns 9new %imu$ator:

=efinedifferent

co$ors for dataf$ows 8for N2M; nsco$or " I$uens co$or Red

?pen the Trace fi$ese

t

fi$e

"9ope

n

out.

tr


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w:

ns

trace#

a$

$f

i$e"


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?pentheN2Mtracefi$

e

setfi$e

9open


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out.n

amw:

nsn

amtrace#a$$

fi$e

=e

finea

U


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fin

is

hU

proced

ur

epr

ocfin

i

sh7G

7

g$ob

a$ns

fi


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$e"

f

i$e

ns

f

$ush

#trace

c$os

efi$

e"

c$

os


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e

fi

$ee(ecnam

out.namP

e(it-

G

Ne(t $ine shou$d be

commented out to ha*e thestatic routing ns rtproto=V

3reate si( nodesset n! 9ns node:set n" 9ns node:set n 9ns node:set n 9ns node:set n 9ns node:set n0 9ns node:


290/345

3reate $inks between the nodesns dup$e(#$ink n! n" !.-Mb "!ms =ropTai$ns dup$e(#$ink n" n !.-Mb "!ms =ropTai$ns dup$e(#$ink n n- !.-Mb "!ms =ropTai$

ns dup$e(#$ink n" n !.-Mb "!ms =ropTai$ns dup$e(#$ink n- n0 !.0Mb "!ms =ropTai$ns dup$e(#$ink n n0 !.0Mb "!ms =ropTai$

+i*e node position 8for N2M;ns dup$e(#$ink#op n! n" orient rightns dup$e(#$ink#op n" n orient rightns dup$e(#$ink#op n n- orient upns dup$e(#$ink#op n" n orient up#$eftns dup$e(#$ink#op n- n0 orient $eft#upns dup$e(#$ink#op n n0 orient right#up

%etup a T3& connection

settc

p

9ne

w2gen

t/

T3&/

Newr


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eno

:

ns

attac

h#

agen

tn!

tcp

setsink9new2gent/T3&%ink/=e$2ck:nsattach#


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agentn0sink

nscon

nect

tcps

ink

tcpse

t

fid_

"


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%etupaFT&o*erT3&c

onnections

etftp9


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new2

pp$ication/F

T&:

ftpa

ttach#agent

tcpftp set type_ FT&


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nsrt

mode$#at".

!downn"

n

nsrtm

ode$#at


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.0up

n"n

ns at !." @ftp start@

n

s

a

t

4

.

!

@

f

i

n

i


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s

h

@

n

s

r

u

n


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E8*o*11%#' MULTICASTING ROUTING PROTOCOL

A0(To write a ns program for imp$ementing mu$ticasting routing protoco$.

Aor0t4(

%tep "A start the program.


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%tep A dec$are the g$oba$*ariab$es ns for creating a newsimu$ator. %tep -A set the co$or

for packets.%tep A open the network animator fi$e in

the name of fi$e in the write mode. %tep0A open the trace fi$e in the name of fi$e "in the write mode.%tep 4A set the mu$ticast routing protoco$to transfer the packets in network. %tep Acreate the mu$ticast capab$e no of nodes.%tep >A create the dup$e(#$ink between the nodes inc$uding the

de$ay time,bandwidth and droppingueue mechanism.

%tep OA gi*e the position for the $inks between the nodes.


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%tep "!A set a udp connection for source node.

%tep ""A set the destination node ,port and random fa$sefor the source and destination fi$es. %tep "A setup atraffic generator 3IR for the source and destinationfi$es.%tep "-A down the connection between any nodes at aparticu$ar time.%tep "A create the recei*e agent for )oining and$ea*ing if the nodes in the group.%tep "0A define the finish procedure.%tep "4A in the definition of the finish procedure dec$are the g$oba$ *ariab$es.

%tep "A c$ose the trace fi$e and namefi$e and

e(ecute the network animation fi$e. %tep ">Aat the particu$ar time ca$$ the finishprocedure.%tep "OA stop the program.

Pror"( 3reate schedu$er3reate ane*entschedu$er witmu$ticastturned on setns 9new%imu$ator#mu$ticast on:

ns mu$ticast

Turn on Tracing


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settf

9openoutp

ut.trw:ns

trace#a$$

tf

Turn on nam Tracings

et


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fd

9o

pen

mcast

.n

amw

:ns

n

amtra

ce#a$$

fd

3reate nodes

set n! 9ns node:set n" 9ns node:


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set n 9ns node:set n- 9ns node:set n 9ns node:set n0 9ns node:set n4 9ns node:

set n 9ns node:

3reate $inks

ns dup$e(#$ink n! n ".0Mb "!ms =ropTai$


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ns dup$e(#$ink n" n ".0Mb "!ms =ropTai$

ns dup$e(#$ink n n- ".0Mb "!ms =ropTai$ns dup$e(#$ink n- n ".0Mb "!ms =ropTai$ns dup$e(#$ink n- n ".0Mb "!ms =ropTai$ns dup$e(#$ink n n0 ".0Mb "!ms =ropTai$ns dup$e(#$ink n n4 ".0Mb "!ms =ropTai$

Routing

pro

toco$Asaydistanc

e*ector&roto

co$

sA3trMcast,=

M,%T,I%Tsetmp

roto=Mset mrthand$e 9ns mrtproto mproto 7G:

2$$ocate group addresses


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set

g

rou

p"9No

de

a$$

ocaddr

:

set

group

9Nod

e


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a$$

oc

add

r:

=&Transport agentfor thetrafficsourceset udp!9new2gent/=&:ns

att

ac

h#age

ntn!

ud

p


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!

u

dp!

setd

st

_add

r_gr

o

up"

udp!

setds

t_


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por

t_

!

setcbr"9new2pp$ication/Traffic/3I

R:cbr"attach#agentudp!

Transp

ortagentforthetra

ffic

sourceset

udp"9new


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_addr

_group

udp"setds

t_port_!setcbr

9new

2pp$ication/Traffic/3I


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R:cbr

attach#

agentud

p"

3reate recei*er

s

etr

c*

r"9ne

w2

gen

t/Nu$$

:

ns

att


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ach

#a

gen

tn0

r

c*r"

ns at".!@n0)oin#grouprc*r"

group"@ setrc*r9new

2gent/Nu$$:ns attach#agent n4 rc*rns at

".0@n4)oin#

grouprc*r

group"@ setrc*r-9new


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2gent/Nu$$:ns attach#agent n rc*r-

ns at.!

@n)oin#grouprc*r-

group"@ setrc*r9new2gent/Nu$$:ns attach#agent n0 rc*r"

ns at.0@n0)oin#

grouprc*r

group@ set

rc*r09new

2gent/Nu$$:ns attach#agent n4 rc*rns at

-.!@n4)oin#grouprc*r0

group

@ setrc*r49new2gent/

Nu$$:ns attach#agent n rc*r-


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ns at -.0 @n )oin#group rc*r4 group@

ns at .! @n0 $ea*e#group rc*r" group"@ns at .0 @n4 $ea*e#group rc*r group"@ns at 0.! @n $ea*e#group rc*r- group"@ns at 0.0 @n0 $ea*e#group rc*r group@ns at 4.! @n4 $ea*e#group rc*r0 group@ns at 4.0 @n $ea*e#group rc*r4 group@

%chedu$e e*ents

ns

at!.0@cbr"start@

nsatO


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.0@

cbr"stop@

nsat!.0

@cbrstar

t@

ns


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atO.

0@cbrstop@

post#processing

nsa

t"!.

!@fin

i

sh@

pro


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cf

in

ish

7G7

g$oba$ ns tf

ns

f$ush

#tr

ace

c$os

e

tfe(ec


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nammc

ast.namP

e(it!

G

For nam3o$ors for

packetsfromtwo

mcastgroupsnsco$or"! red

nsco$

or


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""

gr

een

ns

co

$or

-!pur

p

$e

nsco$

or-"

gr


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een

Manua$ $ayoutA order of the $ink is significant

ns dup$e(#$ink#op n! n" orient rightns dup$e(#$ink#op n! n orient right#upns dup$e(#$ink#op n! n- orient right#down %how ueue on simp$e( $ink n!#n"ns dup$e(#$ink#op n n- ueue&os !.0

+roup ! source

udp!setfid_"

!

n!co$or

redn! $abe$ @%ource "@


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+roup

"source

udp"setfid_""

n"

co$orgr


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een

n"$abe$@%ource@

n0$abe$@R

ecei*er


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"@


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n0 co$or b$ue

n4$abe$@R

ecei*er@

n4co$orb$

uen$

a


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be$

@

Rec

ei*er

-@

n

co$or

b$ue

na

dd#markm


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!red

nde$et

e#markm!@

2nimation rate

nsse

t#ani

mation#

r


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ate

-

.!m

s

ns

r

un


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E8*o*11%/' CARRIER SENSE MULTIPLE ACCESS

A0(To write a ns program for imp$ementing carrier sense mu$tip$e access.

Aor0t4(

%tep "A start the program.%tep A dec$are the g$oba$*ariab$es ns for creating a newsimu$ator. %tep -A set the co$orfor packets.%tep A open the network animator fi$e in the write mode.

%tep 0A open the tracefi$e and the win fi$e inthe write mode. %tep 4Atransfer the packets innetwork.%tep A create the capab$e no of nodes.


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%tep >A create the dup$e(#$ink between the nodes inc$uding thede$ay time,bandwidth and dropping

ueue mechanism.

%tep OA gi*e theposition for the $inks

between the nodes. %tep"!A set a tcp connectionfor source node.%tep ""A set thedestination node usingtcp sink.%tep "A set the windowsie and the packet siefor the tcp. %tep "-A setup the ftp o*er the tcpconnection.

%tep "A.set the udp and tcp connection for the source and destination.%tep "0A create the traffic generator 3IRfor the source and destination fi$es. %tep"0A define the p$ot window and finishprocedure.%tep "4A in the definition of the finish procedure dec$are the g$oba$ *ariab$es.

%tep "A c$ose the trace fi$e and namefi$e ande(ecute the network animation fi$e. %tep ">Aat the particu$ar time ca$$ the finish

procedure.%tep "OA stop the program.


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Pror"(

setn

s9n

ew

%imu$

ato

r:

nsco

$o

r"

b$ue


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ns co$or redset fi" 9open out.tr w:set

winfi

$e9o

penJin

Fi$e

w

:ns

tra

ce#

a$$


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fi"

se

tf

i9op

en

out

.namw

:

ns

namtra

ce#a$$


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fi

p

roc

finis

h

7G7

g$oba$

nsfi

"fi

nsf

$u


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sh#

tr

ace

c$os

e

fi"c$ose fie(ecnamout.namP

e(it!G


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set n! 9ns node:set n" 9ns node:set n 9ns node:set n- 9ns node:set n 9ns node:

set n0 9ns node:n" co$or redn" shape bo(ns dup$e(#$ink n! n Mb "!ms =ropTai$ns dup$e(#$ink n" n Mb "!ms =ropTai$ns simp$e(#$ink n

n- !.-Mb"!!ms=ropTai$

ns simp$e(#$ink n- n!.-Mb "!!ms

=ropTai$set $an 9ns newBan @n- n n0@ !.0Mb !ms BB]ueue/=ropTai$ M23/3sma/3d 3hanne$: set tcp 9new2gent/T3&/Newreno:ns attach#agent n! tcpset

sink9new2gent

/T3&%ink/=e$2c

k:

nsattach#agent

n


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sink

ns

connecttc

psinktcp

setfid_"tcp set window_ >!!!tcp set packetsie_ 00

set

ft


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p9

ne

w2

pp$ica

ti

on/F

T&:f

t

patt

ach#ag

entt

cp


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ftp set type_ FT&set udp 9new 2gent/=&:ns attach#agent n" udpset nu$$ 9new 2gent/Nu$$:ns attach#agent n0 nu$$

ns connect udp nu$$udp set fid_

set cbr 9new 2pp$ication/Traffic/3IR:


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cbra

ttach#

agent

udp

cbrs

ett

yp

e_3IR


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set time !."set now 9ns now:set

cwnd9

tcp

%ource

set

cw

nd_:s

et

wnd

9tc


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p%o

ur

ce

setwi

nd

ow_:

puts

fi$e

@now

cwnd@

ns at 9e(pr nowDtime: @p$otwindow


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tcp%ource fi$e@G

ns at ".! @p$otwindow tcp winfi$e@ns at 0

@ns

trace#annotateE@packetdropE@@ns at

"0.!@finish@ns run

?utputA


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CS6411 Network Lab Manual

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