opnet讲座 Modeler-Day1原版完整课件

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Modeler

Training

(Day

1)2BeijingCredit

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reservedCourse

ContentDAY

1:IntroductionModeling

FrameworkRunning

The

DESBuilding

a

First

Network

{Lab}Traffic

ModelingwiththeStandard

Application

Models{Labs}DAY

2:Events

and

Event

List

ConceptsProcessModeling

Methodology

(PMM){Lab}Debugging

Techniques

{Labs}Modeling

Applications

•

WirelessModeling{Labs}ModelingCustom

Wireless

Effects{Labs}DAY

3:BasicWiMAX

Configuration

{Labs}Using

WiMAX

Models

forPlanningand

Design{Labs}Using

WiMAX

Models

forAnalysisand

Testing{Labs}Beijing

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Co.,

Ltd.IntroductionWhat

is

Modeler?BeijingCredit

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reserved4Anenvironmentforbuildingprotocols

anddevice

models.Anenvironmenttoplanchangesbyillustratinghowthe

networked

environment

will

perform.Anenvironmentthatincludeshundredsofpre-builtmodels,

usedtostudyperformancechangesofyournetwork:

organizationalscaling,technologychanges,andapplication

deployment.ExpectationsBeijingCredit

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reserved5Prerequisites:–Ability

toprogram

in

Cor

C++

orat

least

be

comfortablein

reading/understanding

CorC++code–Basicunderstanding

of

networksFor

basicinformation,

seeo/library/glossary/blglossary.htm

ooThis

class

will

move

quickly

Don’t

hastate

to

ask

questions. Itwillenhanceyourlearning

experience.About

half

lecture,

half

lab概况成立于

1986上市公司

(Nasdaq:

OPNT)总部在马里兰州的贝锡斯达(Bethesda)大约600名员工遍及全球的办事处及分销机构顶级的软件和服务网络建模与仿真应用性能分析网络规划、工程和运营辉煌的金融记录连续的赢利历史Trailing12-month

revenue

of

over$120M大约25%的收入投入到研发广大的客户群研发组织运营商企业政府及承包商关于OPNET公司In

Recognition

of

Visionary

use

of

Information

TechnologyNetworkWorldTop

200BeijingCredit

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reserved6北京怡嘉行科技有限公司介绍我们的公司成立于1999年总部位于北京OPNET产品中国区签约代理商我们为您提供基于行业的产品和解决方案专业的技术支持定制化的培训咨询服务相关产品的集成及开发我们的客户国防及政府电信运营商及设备制造商企业大学院校及科研机构BeijingCredit

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reserved7OPNET

解决方案BeijingCredit

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reserved8OPNETWORKOPNETWORKisthelargestconferenceintheworldonnetworkandapplication

modelingand

simulation--offering

adynamicrangeof

symposiums,

case

studies,

and

modeling

sessionstaught

byOPNET

experts.•OPNETWORK

(includingcourse

materials,

models,

nightly

entertainment,

all

meals,

and

online

proceedings)

is

free

to

all

OPNET

clients

and

client

organizations.Thoseinterestedinattendingwhoarenotfromaclientorganizationwillbe

considered

on

a

case-by-casebasis.This

year’s

conference

heldatthe

ReaganBuildingin

Washington,D.C.ForCurrentInformation:

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reserved9Beijing

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FrameworkThe

Three-Tiered

OPNET

HierarchyThreedomains:

Network,

node,

and

processNode

model

specifiesobjectin

network

domainProcess

model

specifies

object

innode

domainProcess

modelrip_udp_v3BeijingCredit

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reserved11Modeler

ArchitectureProject

Editor–Createnodeandlinkobjectsto

represent

network

topology–Layouttrajectoriestodefinenode

mobilityNode

Editor–Representprotocoland

applicationfunctions,andtheflow

ofdatainternal

to

the

deviceProcess

Editor–UseFiniteStateMachinesto

defineprotocollogicandcontrol

flow–C/C++

code

controls

the

behavior

ofeach

stateOther

Editors–PacketFormat,

Antenna

Pattern,

and

Modulation

etc.BeijingCredit

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reserved13Features

of

the

Project

EditorNode

ModelingProcess

ModelingOther

EditorsBeijing

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of

the

Project

EditorOverviewBeijingCredit

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reserved15Project

Editor:–Workflow–More

Details

ofthe

Project

WorkspaceMap

BackgroundsZoomingThreshold

ValueAnnotation

PaletteProject

Workspace{Lab}–ModelsBuilt-in

modelsDerivingand

CreatingNew

Devices

{Lab}–ObjectAttributesClient-Server

ConfigurationExample–Statistics–ProductDocumentationThe

Project/Scenario

WorkflowCreate

projectCreate

baseline

scenario–Import

or

create

topology–Importor

create

traffic–Choose

results

and

reports

to

be

collected–Run

simulation–View

resultsDuplicate

scenario–Make

changes–Re-run

simulation–Compare

resultsIterateBeijingCredit

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reserved16Projects

andScenariosProject:

MANET

StudiesBaseline

Model15%trafficincrease

over

baselineFailureofthree

Central

devices15%trafficincrease

with

higher

data-rate

radiosBeijingCredit

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reserved17Compare

results

between

scenariosProjectEditorSeveraltoolsareincludedinModelertointuitivelymapfrom

network

specifications

to

a

modeled

network.–UsetheStartup

Wizardto

specifythe

initialenvironmentof

ascenario.–Select

objectsfroman

ObjectPalette.–Use

Rapid

Configuration

to

quickly

deploy

common

network

topologies.–Use

Nodeand

Link

objectsto

represent

actualtopology.–Edit

the

Attributesof

nodesandlinks

tocustomizetheirbehavior.Example

networkmodel:BeijingCredit

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reserved18Map

BackgroundsModeler

includes

several

maps

thatcan

be

loadedasbackgrounds

for

network

models.Mapbackgrounds

providea

physical

context

for

model

specification.Modelsaremoreeasilyinterpretedwhensetinapropergeographical

context.Distancebetween

nodes

can

bea

factor

in

affecting

simulation

results.Maps

can

be

importedas

well

as

shownbelow.–.tiff,

geotiff,MapInfo,

CADRGImage

of

part

of

ChicagoBeijingCredit

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reserved19View/hidemaps

by

choosing

View/

Background

/

Set

PropertiesGeotiff,

MapInfo,

MrSID

and

CADRG

images

automatically

appear

atthe

correctlatitudeand

longitude

position.MIF

maps(default)TIFF

and

GeoTIFFGeospatial

maps

not

provided,

but

canbedisplayed-MrSID,

GeoTIFF,

CADRG/CIBRasterSetting

Background

MapsBeijingCredit

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reserved20Zooming

&

PanningZoomtoRectanglebuttonontheProjectEditortoolbar

allowsthe

usertodefinea

rectangular

area

to

magnifyZoomtoPreviousbuttonreturnstheworkspacetothe

previousmagnificationlevelMouseScrollWheelorUpandDownkeysfor

small

incrementsRight-click

on

the

workspace

to

open

the

workspace

pop-up

menu–Zoom

in–Zoom

to

all–Zoom

out–Zoom

to

selection–Zoom

to

windowBeijingCredit

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reserved21Changing

Icon

SizeYoucanscalethesizeofanicon

onthescreentoimprovethe

appearance

of

the

topologyView/Layout/ScaleNode

Icons

Interactively…BeijingCredit

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reserved22Open

by

selectingTopology

/

Open

Annotation

PaletteAddrectangles,

circles,

lines

andtext

to

models

toenhancetheir

appearanceThis

method

is

an

effective

way

tographically

illustrate

and

document

thechanges

made

to

amodelDoes

not

affect

analysisAnnotations

can

be

temporarily

hiddenAnnotation

PaletteBeijingCredit

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reserved23Network

BrowserTheNetworkBrowsercanbeusedtolocateobjectsinyour

network.Choose

View

/

Show

Network

BrowserTypeasearchstringintothe“Find”boxtoshowobjectswith

that

stringintheir

names.BeijingCredit

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reserved24Managing

Projects

and

ScenariosChange

the

scenario

name

here.Change

thesimulation

duration.Managing

scenarios

allows

you

to

examine

the

status

ofscenarioresults,changeproject/scenarionamesandrun

multiplesimulations

sequentially.Collectresults

onmultiple

scenarios

bychangingtheresultscolumnto<recollect>.

ClickingOKwillstartasimulationrunfor

each

scenariowith

<recollect>

set.Change

the

project

name

here.Okwillwriteall

ofthechangesto

the

project.BeijingCredit

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reserved25Asubnetworkabstractsnetworkcomponentsspecified

within

it

intoa

singleobject.Subnetworks:–Represent

identicalconstructs

in

anactualnetwork.–Havenobehavioral

aspects,

but

simplify

representationof

large

networks.–May

be

stationary

ormobile.NetworkObjects

-

SubnetsBeijingCredit

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reserved26Why

Use

Subnets?Subnets

area

powerfulmechanism

for

breakingdown

asystem’s

complexity

throughabstraction.Consider

twoconnectedEthernet

networks

inSan

FranciscoandLos

Angeles.BeijingCredit

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reserved27NetworkObjects-

NodesNodeobjectsarerepresentedbyicons.

Different

iconsmayrepresentthesameunderlyingobject.

Icons

shown

are

the

defaulticons.Afixednoderemainsstationaryduringa

simulation.A

mobile

node

changes

position

during

a

simulation,

following

an

assigned

trajectory

or

using

vectorbasedmobility(groundspeed,bearing,and

ascentrate).

Trajectoriescaneasilybecreated

graphically

in

Modeler,

orby

ASCII

textfiles.A

satellite

nodechanges

position

during

a

simulation,

following

an

assigned

orbit.SatelliteMobileFixedBeijingCredit

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reserved28Model

Library

ComponentsThe“ModelLibrary”containsavarietyofobjectsusedfor

creating

networksTrafficgenerators

(workstations,

servers,

stations,

etc.)Network

devices

(hubs,

bridges,

switches,

routers,

etc.)Links(SONET,

PPP,

FDDI,

10BaseT,

ISDN,xDSL,

etc.)Vendor

device

models

(Cisco

Systems,

3Com,

Nortel,

Lucent,

HP,

etc.)These

modelsare

ready-to-use

tocreate

networks

andpredict

performancebehavior.BeijingCredit

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reserved29Model

Naming

ConventionBeijingCredit

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reserved30OPNET’sstandardmodelsuiteusesaspecificnaming

conventionfor

its

nodemodels:<protocoln>…<protocoln

>_<function>_<modifier><protocoln>isanabbreviationthatspecifiesaparticular

protocol

thatis

supported

within

the

model. Thevariablen

represents

the

number

of

protocolinterfaces

withinthatmodel.<function>

is

anabbreviation

thatindicates

the

general

functionof

the

node,e.g.

gateway,workstation,server.<modifier>

indicates

thelevelof

derivationof

the

model.Model

Naming

Convention

(cont.)Levels

of

derivation

(<modifier>value)–adv: advanced

model. Allnodeattributesareavailableand

attribute

values

areset

totheir

defaults.–int: intermediate

model. Attributesthatareunlikelytobechanged

arehiddenand

typicalvalues

areappliedtothevisibleattributes.–Models

withno

valuefor

modifier

arederived

from

intermediate

models. Additionalattributes

arehiddenand

only

attributes

neededfor

parametric

studies

arevisible.Example:

ethernet128_hub_advThis

modelrepresentsa

hub

with128ethernet

interfaces.Sinceit

is

an

advancedmodel,

allthe

model’s

attributes

are

visible

andeditable.BeijingCredit

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ModelsNaming

convention

forvendormodels<Vendor_Name>_<Device_Name>_<Number_of_Slots>_<Configuration>Example:CS_4000_3s_e6_f_fr2_sl2This

model

represents

aCiscoSystems

4000Router

with

3slots,6

ethernet

ports,1

FDDIport,2

frame

relay

ports,and2

SL-IPports.View

description

of

thenodeby:–Right-clicking

on

the

node

in

the

object

palette.–Right-clicking

on

the

nodeintheworkspaceandselecting

“View

NodeDescription”.BeijingCredit

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reserved32Network

Objects

-

LinksLinkobjectsmodelphysicallayereffectsbetweennodes,

such

as

delays,

noise,

etc.Awirelesslink,establishedduringa

simulation,canbecreatedbetweenanyradio

transmitter-receiver

channel

pair.

Satelliteand

mobilenodesmustusewirelesslinks.

Fixednodesmayusewirelesslinks.

Awirelesslinkisnotdrawnbutisestablishedifnodescontain

radio

transceivers.BeijingCredit

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reserved33A

bus

linktransfers

data

amongmany

nodes

and

isa

sharedmedia.Apoint-to-pointlinktransfersdatabetween

twofixed

nodes.Wireless

linkNetwork

Objects

-

LinkAn

appropriate

link

must

be

chosen

tomatch

interfaces

on

connected

devices.–Data

rate,

protocol,

and

number

of

available

interfaces

are

the

requirements

that

must

be

met.Linkmodel

naming

convention:–<protocol>_<modifier>Example:–100BaseT_advBeijingCredit

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reserved34Customizing

Palettes-

ModelList

Method123456BeijingCredit

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reserved35Creating

New

DevicesBeijingCredit

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reserved36AlthoughOPNETModelerincludeshundredsofstandardandvendor

devices,youmay

need

to

customize

models.Thereareseveralwaystocreatenewdevicesorderivemodelsfrom

the

existingdatabase

tocustom

specifications.–Twomethods

discussed

here

tochangeand

existing

modelDeriving

a

new

modelUsing

Device

Creator–Modeling

newdevices

and

protocols

discussed

later

in

courseFromtheModelDescription

dialogboxofanexistingmodelDerive

a

new

model

based

ontheexistingstandardor

vendormodelAlter

the

attributesof

the

new

modelSaveitasanewmodelwith

a

new

nameDeriving

New

ModelsBeijingCredit

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reserved37Device

CreatorCreate

Custom

Device

Model–Providestheabilityto

automatically

create

a

particular

devicewithaspecific

configuration.–Typicaldevices

include

routers,

switches,hubs,bridges,vendor

specific

devices,andLAN

models.Inthe“Topology”pull-down

menu.Advantages–Allowsyoutoselectanynumber

of

interfaces

and

protocols

thata

devicewill

needtosupport.–Providesyou

more

controlover

memoryefficiency,reducing

simulation

run-time.BeijingCredit

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reserved38Object

AttributesBeijingCredit

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Modeler

objectshave

attributesAttributes

define

the

object

and

control

its

behavior–Secondattribute

is

“model”

-

this

is

the

filename

of

the

object–Attributevaluesmayvarybetweenobjectsofthesame

modelExample:

Two

routers

of

thesame

model

mayhavedifferent

routing

parameters,

two

demands

mayrepresent

different

amountsof

traffic–Attributes

may

havesub-attributesToviewor

change

anobject’s

attributes–Right-click

on

the

object–Select

“Edit

Attributes”or

“AdvancedEdit

Attributes”Promoting

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ValuesBeijingCredit

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reserved40You

can“promote”

an

attribute. This

meansthat

you

assign

a

value

at

a

higher

hierarchical

level.Passingcontrolofalower-levelobjecttoahigherlevel

provides

moreflexibility

in

how

objects

are

used.Youcanleaveanattributeunspecifiedateventhenetwork

level,

andassignavalueat

runtime.Group

Attribute

AssignmentBeijingCredit

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reserved41Agroupofobjectscanhavetheirattributesassigned

simultaneously

by

usingthe

“Apply

Changes

to

Selected

Objects”

button.Notethat

selected

objects

that

do

not

contain

theattribute

being

changed

willnot

beaffectedby

thegroupassignment.Where

to

Get

HelpTo

view

the

manual,

choose

Product

Documentation

from

the

Help

menu.Modelhelpisaccessedbyright-clickingiconsintheobjectpaletteorby

rightclickingobjectsintheProjectworkspaceandselecting“ViewNode

Description.”Clickthequestionmarkinattributedialogboxestoviewthedescriptionof

thatattribute.ToolTips:placeyourcursoroveranyobjectandwaitonesecondtogeta

brief

description

ofthatobject.BeijingCredit

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reserved42Lab:

Using

the

Project

EditorBeijingCredit

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reserved43Purpose:–“Play”

withfeaturesof

the

Project

Editor–Usethe

“DeviceCreator”

and

modelderivationtocreate

new

node

models–Modify

attributes’

values

inorder

to

model

non-default

behavior–Search

the

product

documentationBeijing

Credit

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ModelingSampleNode

ModelBeijingCredit

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reserved45Node

models

support–Layering

ofprotocol

functions–Dynamicinter-module

monitoring–Arbitrary

node

architectures–Definitionofnodeclasses

through

attribute

promotionethernet_wkstn_adv

Node

ModelNode

EditorBeijingCredit

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reserved46TheNodeEditorprovidestheresourcesnecessaryto

model

theinternal

functionsof

nodes.Youhaveaccesstodifferentmoduleswhichareusedto

modelinternalaspectsof

nodebehavior.Modulesrepresenttheinternalcapabilitiesofanodesuch

as:–Data

creation–Transmission–Reception–Storage–Internal

routing–QueuingNode

EditorToolbarNode

WorkspaceCreatemodule

connectionPacket

stream

/statistic

wire

/tx/rxassociationCreatetransceivers(tx/rx)

point-to-point

/bus

/radio

/antennaCreate

processorCreate

queueBeijingCredit

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reserved47Processor.Amodulethatrepresentsthemostgeneralbuildingblockofnode

models

and

arefully

programmable.

Youcan

specify

the

behavior

of

a

processor.

It

can

be

connected

to

other

modules

to

share

information

or

packets.Queue

module.

Amodule

thatprovidesa

superset

of

thefunctionality

ofprocessormodules,andcanalsobufferandmanageacollectionofdata

packets.

Queue

modules

canexecutean

arbitrary

process

model

that

describes

the

behavior

ofa

particular

process

or

protocol,

andcan

be

connected

viapacket

streams

to

other

modules.Node

Editor

-

ToolbarBeijingCredit

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reserved48Packet

stream.

A

connection

between

modules

that

carries

datapackets

from

a

sourcemodule

toa

destination

module.

They

represent

the

flow

of

dataacross

the

hardware

and

software

interfaces

within

a

communicationsnodeStatisticwire.

A

connection

between

modules

that

conveys

numeric

values

between

devicesor

processes

in

the

same

node.

Statistic

wiresare

primarily

used

to

allow

processes

to

monitor

changes

in

state

and

performance

ofthe

devices

that

make

up

a

node,

and

to

createasimple

signaling

mechanism

between

processes.Logicalassociation.

A

connection

used

toindicate

that

arelationship

exists

between

two

modules

in

a

node

model,

forexample,

between

a

receiver

and

transmitter

used

as

a

pair.

Logical

associationsdo

not

carryany

data.Node

Editor

-

ToolbarBeijingCredit

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reserved49Transmitters:

theoutbound

interfacebetweenpacketstreamsinside

anode

andcommunicationslinks

outside

the

node.Receivers:

theinboundinterface

betweencommunicationslinksoutside

anode

and

packet

streamsinsidea

node.Point-to-pointBusRadioPoint-to-pointBusRadioAntenna:Amodulethatisusedto

specify

theantenna

properties

for

radio

transmitteror

receiver

modules.AntennaNode

Editor

-

ToolbarBeijingCredit

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reserved50The“NodeInterfaces”option

allowsyoutospecifyvarious

characteristicsof

the

node.Nodetypes

(fixed,mobile,

satellite)KeywordsAttributesNode

DocumentationCommentsSpecifying

Node

InterfacesBeijingCredit

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reserved51Specifying

Available

Node

StatisticsBeijingCredit

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reserved52NodeStatisticsallows

youtoselectwhich

statisticscanbechosen

forcollectionfromwithin

the

Project

Editor.By

selecting

an

empty

field

inthe“Orig.Name”column,

a

table

of

available

statistics

appears.Selectingastatisticfromthe

“AvailableStatistics”

table

addsthestatistictothe

“Statistic

Promotion”

table.Ifastatisticisnot

promoted,

ausercan

still

collectit

using

the

“Probe

Editor”.Specifying

Available

Node

StatisticsBeijingCredit

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reserved53Lab:

Node

ModelingBeijingCredit

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reserved54LabBook:

Lab:

NodeModelingBank

transactions

originatein

Washington,

D.C.

(WDC)

and

are

routedtoPhiladelphiaviaa

telephone

lineandmodem

capable

of

transmitting

9,600bits/second.Thesizeof

atransactionvaries

accordingto

a

normaldistribution

witha

mean

sizeof3,200bits

and

a

varianceof400bits.Transactions

aremodeledas

exponentialinterarrivals,

withameaninterarrival

time

of0.5

sec/trans.The

goalistoanalyzeperformanceof

asystem

insteady

state.Create

atransaction

packet

with2

fields,

sourcenode,

and

destination

node.

Eachfield

hasasize

of

64bits.Preview: Thislabmodelstheflowofbanktransactions

(representedaspackets)fromWashington,D.C.to

Philadelphia.Inordertomeasuretheperformanceofthissimplenetwork

inameaningfulmanner,youmustdefinespecificquestions

that

your

model

isdesigned

toanswer.Design

thelab

toanswer

the

followingquestions:–Does

thequeue

size

of

the

WDCtransmitter

steadily

increase?–What

is

thethroughput

(inbits/second)

at

theWDC

transmitter?–What

isthethroughput

(inbits/second)at

the

Philadelphia

receiver?–What

is

theutilizationof

theDC

toPhiladelphialink?BeijingCredit

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reserved55Understandingthe

QuestionBeijing

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Co.,

Ltd.北京怡嘉行科技有限公司Process

ModelingAgendaBeijingCredit

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reserved57Conceptual

goals–Processmodels–Custom

statistics–Kernel

ProceduresTools–Process

EditorProcess

ModelsProcess

model

components–State

transition

diagrams–BlocksofC

code–OPNET

Kernel

Procedures

(KPs)–State

variables–Temporary

variablesA

process

is

aninstanceof

aprocess

modelProcesses

can

dynamically

create

childprocessesProcesses

canrespond

tointerruptsBeijingCredit

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reserved58ProcessModelObjects-

StatesTheinitialstate

is

the

place

where

execution

begins

ina

process.A

forced

state

does

notallow

apause

during

the

process.An

unforced

stateallows

a

pauseduring

theprocess.Laterchapterswillfullydiscussthedifferencesbetween

these

types

ofstates.Initial

stateBeijingCredit

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reserved59Forced

stateUnforced

statered green redForced

StatesForced(green)andunforced

(red)statesdiffersignificantly

in

execution

timing.In

a

forced

state,

the

process:–Invokestheenter

executives–Invokesthe

exit

executives–Evaluatesallcondition

statements–Ifexactlyonecondition

statement

evaluatestotrue,

thetransitionistraversedto

the

next

state.Transition

to

next

stateBeijingCredit

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reserved60Transition

to

next

stateForced

(green)

statesEnter

execsinvokedNoblocking

or

waitingExitexecsinvokedEnter

execsinvokedExitexecsinvokedNoblocking

or

waitingUnforced

StatesIn

an

unforced

state,

the

process–Invokestheenter

executives–Placesamarkeratthemiddle

of

thestate–Releasescontroltothe

Si