Browsing CODE [Attribute]

Browsing CODE [Attribute]

09-10/12/2014

NS3 Workshop:RIET College, Jaipur

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RoadMap ●

Object Model

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Attributes

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Tracing

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Gnuplot

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NS3 Workshop:RIET College, Jaipur

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Object Model Classes Derived from following classes:Class Object

Properties : - Type & Attribute System - Object Aggregation - Smart-pointer

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Class ObjectBase

Properties : - Type & Attribute System - Object Aggregation - Smart-pointer

NS3 Workshop:RIET College, Jaipur

Class SimpleRefCount

Properties : - Type & Attribute System - Object Aggregation - Smart-pointer

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Memory Management Maintain an internal reference count to determine when an object can safely deleted: - Ref() - increment the count of the object instance - UnRef() - decrement the count of the object instance

When reference count falls to zero the object is deleted NS3 provides a smart pointer Ref() and UnRef() method.

class Ptr that provide a pair of

Reference counted object are usually allocated using a templated Create or CreateObject methods

Example : Create a Node Ptr n= CreateObject; 09-10/12/2014

NS3 Workshop:RIET College, Jaipur

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Object Aggregation ●

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Object can be aggregated to access each other , and for the user to easily access individual object in an aggregation. Avoid encompassing all possible functionality Node

Mobility

Retrieving an object Ptr mob= node1->GetObject(); Aggregate an object 09-10/12/2014

NS3 Workshop:RIET College, Jaipur node2->AggregateObject(mob)

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Example ●

Node –

Aggregate point to point netdeivce to node

Sample Code

Ptr n = CreateObject(); Ptr p2p = CreateObject(); p2p->SetNode(n); n->AggregateObject(p2p);

09-10/12/2014

NS3 Workshop:RIET College, Jaipur

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Typeid ●

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This class provide a unique identified for an interface This is a class that records a lot of metainformation about the subclass of Object classes –

the base class of the subclass

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the set of accessible constructor in the subclass

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the set of attributes accessible in the subclass

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Tracing mechanism

09-10/12/2014

NS3 Workshop:RIET College, Jaipur

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TypeId GetTypeId(void) ●

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Return TypeId-object to identify and characterize object. Contain object type , constructor and parent object Define the object attribute and trace source

09-10/12/2014

NS3 Workshop:RIET College, Jaipur

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Typeid Object

Node

NetDevice

Typeid



09-10/12/2014

NS3 Workshop:RIET College, Jaipur

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Attributes ●

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Goal of Attribute system is to organize the access of internal members objects of a simulation. Most often user is interested in studying or tracing particular internal variables. Example: –

What is network performance if we change the packet size?

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How transmission time varies with data rate?

09-10/12/2014

NS3 Workshop:RIET College, Jaipur

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Attribute ●

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Set a default value of member variable Set or Get the values of an already instantiated queue Example: –

Modify the no of Route Request Retry attribute and check the result in AODV Classes like Node

Classes like Node

GetAttribute()

SetAttribute() Typeid

AddAttribute() 09-10/12/2014

NS3 Workshop:RIET College, Jaipur

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Attribute ●

How to add attribute? –

Typeid AddAttribute(...)

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Sample Code

Brief Description

Name of attribute Type of value Accessing variable

09-10/12/2014

NS3 Workshop:RIET College, Jaipur

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AODV ●

List of Attributes: –

Hello Interval

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RreqRetries

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NetDiameter

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PathDiscoveryTime

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MaxQueueLen

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MaxQueueTime

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Gratuitous Reply

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and few more

09-10/12/2014

NS3 Workshop:RIET College, Jaipur

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Example ●

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Example code –

ns3.21/src/aodv/aodv.cc

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copy in scratch/

Modify the code and create 10 nodes with RandomWalk2dMobilityModel and show the output in NetAnim Modified Topology

Current Topology

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NS3 Workshop:RIET College, Jaipur

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4 1

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Adding New Typid ●

Example -1 –

Add new attribute in AODV Routing Protocol of boolean type.

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Attribute Detail ● ●

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Name -SampleAttribute Type - Boolean

NS3 Workshop:RIET College, Jaipur

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To be Continued ...

09-10/12/2014

NS3 Workshop:RIET College, Jaipur

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