Practical 10:: Program to Simulate Star Topology

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/*

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* published by the Free Software Foundation;

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* GNU General Public License for more details.

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#include “ns3/core-module.h”

#include “ns3/network-module.h”

#include “ns3/netanim-module.h”

#include “ns3/internet-module.h”

#include “ns3/point-to-point-module.h”

#include “ns3/applications-module.h”

#include “ns3/point-to-point-layout-module.h”

// Network topology (default)

//

using namespace ns3; NS_LOG_COMPONENT_DEFINE (“StarAnimation”);

int

main (int argc, char *argv[])

{

//

// Set up some default values for the simulation.

//

Config::SetDefault (“ns3::OnOffApplication::PacketSize”, UintegerValue (137));

//??? try and stick 15kb/s into the data rate

Config::SetDefault (“ns3::OnOffApplication::DataRate”, StringValue (“14kb/s”));

//

// Default number of nodes in the star. Overridable by command line argument.

//

uint32_t nSpokes = 8;

std::string animFile = “star-animation.xml”;uint8_t useIpv6 = 0;

Ipv6Address ipv6AddressBase = Ipv6Address(“2001::”);

Ipv6Prefix ipv6AddressPrefix = Ipv6Prefix(64);

CommandLine cmd;

cmd.AddValue (“nSpokes”, “Number of spoke nodes to place in the star”, nSpokes);

cmd.AddValue (“animFile”, “File Name for Animation Output”, animFile);

cmd.AddValue (“useIpv6”, “use Ipv6”, useIpv6);

cmd.Parse (argc, argv);

NS_LOG_INFO (“Build star topology.”);PointToPointHelper pointToPoint;

pointToPoint.SetDeviceAttribute (“DataRate”, StringValue (“5Mbps”));

pointToPoint.SetChannelAttribute (“Delay”, StringValue (“2ms”));

PointToPointStarHelper star (nSpokes, pointToPoint);

NS_LOG_INFO (“Install internet stack on all nodes.”);InternetStackHelper internet;

star.InstallStack (internet);

NS_LOG_INFO (“Assign IP Addresses.”);if (useIpv6 == 0)

{

star.AssignIpv4Addresses (Ipv4AddressHelper (“10.1.1.0”, “255.255.255.0”));

}

else

{

star.AssignIpv6Addresses (ipv6AddressBase, ipv6AddressPrefix);

}

NS_LOG_INFO (“Create applications.”);

//

// Create a packet sink on the star “hub” to receive packets.

//

uint16_t port = 50000;

Address hubLocalAddress;

if (useIpv6 == 0)

{

hubLocalAddress = InetSocketAddress (Ipv4Address::GetAny (), port);

}

else

{

hubLocalAddress = Inet6SocketAddress (Ipv6Address::GetAny (), port);

}

PacketSinkHelper packetSinkHelper (“ns3::TcpSocketFactory”, hubLocalAddress);

ApplicationContainer hubApp = packetSinkHelper.Install (star.GetHub ());hubApp.Start (Seconds (1.0));

hubApp.Stop (Seconds (10.0));

//

// Create OnOff applications to send TCP to the hub, one on each spoke node.

//

OnOffHelper onOffHelper (“ns3::TcpSocketFactory”, Address ());onOffHelper.SetAttribute (“OnTime”, StringValue

(“ns3::ConstantRandomVariable[Constant=1]”));onOffHelper.SetAttribute (“OffTime”, StringValue

(“ns3::ConstantRandomVariable[Constant=0]”));ApplicationContainer spokeApps;

for (uint32_t i = 0; i < star.SpokeCount (); ++i)

{

AddressValue remoteAddress;if (useIpv6 == 0)

{

remoteAddress = AddressValue(InetSocketAddress (star.GetHubIpv4Address (i), port));

}

else

{

remoteAddress = AddressValue(Inet6SocketAddress (star.GetHubIpv6Address (i), port));

}

onOffHelper.SetAttribute (“Remote”, remoteAddress);spokeApps.Add (onOffHelper.Install (star.GetSpokeNode (i)));

}

spokeApps.Start (Seconds (1.0));

spokeApps.Stop (Seconds (10.0));

NS_LOG_INFO (“Enable static global routing.”);

//

// Turn on global static routing so we can actually be routed across the star.

//

if (useIpv6 == 0)

{

Ipv4GlobalRoutingHelper::PopulateRoutingTables ();

}

// Set the bounding box for animation star.BoundingBox (1, 1, 100, 100);

// Create the animation object and configure for specified output AnimationInterface anim (animFile);

NS_LOG_INFO (“Run Simulation.”);Simulator::Run ();Simulator::Destroy ();NS_LOG_INFO (“Done.”);

return 0;

}

Output:

To Plot the graph consider the following files 
starnew.txt