How to Begin Implement Network Load and Hop Count in NS3

To begin implementing the Network Load and Hop Count using NS3, we can replicate a network including traffic flows and then estimate the total load such as traffic volume or packets that are sent and the volume of hops packets attaining its destination. Here’s a general method on how to begin the Network Load and Hop Count using NS3:

Steps to Implement Network Load and Hop Count in NS3

1. Understand the Metrics

1. Network Load:
   • It denotes the volume of data traffic which are managed by the network that normally estimated as:
     • Packets are sent for each second.
     • Bytes broadcasted for every second (throughput).
     • Total packets or bytes through the simulation period.
2. Hop Count:
   • The amount of intermediate nodes packet passes through for attaining their end node.

2. Set Up the NS3 Simulation Environment

1. Install NS3:
   • Make sure that we have installed and downloaded NS3 on the system.
2. Choose a Network Type:
   • Based on the simulation scenario, make use of PointToPoint, Wifi, or Adhoc networks.

3. Configure Traffic and Routing

• Configure traffic to utilize an application such as OnOffApplication or UdpEchoApplication.
• Allow routing to permit the packets for passing through several hops.

4. Measure Metrics

1. Network Load:
   • Measure traffic volume of bytes/packets transmitted utilising FlowMonitor module.
2. Hop Count:
   • Estimate the volume of hops to leverage PacketSocketAddressTag or analyse the routing tables.

5. Implement Load and Hop Count Calculation

Here’s a sample script for estimating the network load and hop count within an ad-hoc wireless network.

Example Script: Network Load and Hop Count in NS3

#include “ns3/core-module.h”

#include “ns3/network-module.h”

#include “ns3/internet-module.h”

#include “ns3/wifi-module.h”

#include “ns3/mobility-module.h”

#include “ns3/applications-module.h”

#include “ns3/flow-monitor-helper.h”

using namespace ns3;

NS_LOG_COMPONENT_DEFINE(“NetworkLoadAndHopCountExample”);

void CalculateNetworkLoad(Ptr<FlowMonitor> monitor, double simulationTime) {

FlowMonitor::FlowStatsContainer stats = monitor->GetFlowStats();

uint64_t totalBytes = 0;

for (auto const &flow : stats) {

totalBytes += flow.second.rxBytes; // Total received bytes

}

double throughput = (totalBytes * 8.0) / simulationTime; // Bits per second

NS_LOG_UNCOND(“Total Network Load: ” << totalBytes / 1e6 << ” MB”);

NS_LOG_UNCOND(“Throughput: ” << throughput / 1e6 << ” Mbps”);

}

void CalculateHopCount(Ptr<OutputStreamWrapper> stream, Ptr<Ipv4Route> route) {

NS_LOG_UNCOND(“Hop Count: ” << route->GetOutputDevice()->GetNode()->GetNDevices());

*stream->GetStream() << Simulator::Now().GetSeconds() << ” Hop Count ” << route->GetOutputDevice()->GetNode()->GetNDevices() << std::endl;

}

int main(int argc, char *argv[]) {

CommandLine cmd;

cmd.Parse(argc, argv);

// Create nodes

NodeContainer nodes;

nodes.Create(10); // 10 nodes in the network

// Configure WiFi

YansWifiChannelHelper wifiChannel = YansWifiChannelHelper::Default();

YansWifiPhyHelper wifiPhy = YansWifiPhyHelper::Default();

wifiPhy.SetChannel(wifiChannel.Create());

WifiHelper wifi;

wifi.SetStandard(WIFI_PHY_STANDARD_80211g);

WifiMacHelper mac;

mac.SetType(“ns3::AdhocWifiMac”);

NetDeviceContainer devices = wifi.Install(wifiPhy, mac, nodes);

// Configure mobility

MobilityHelper mobility;

mobility.SetPositionAllocator(“ns3::RandomRectanglePositionAllocator”,

“X”, StringValue(“ns3::UniformRandomVariable[Min=0.0|Max=100.0]”),

“Y”, StringValue(“ns3::UniformRandomVariable[Min=0.0|Max=100.0]”));

mobility.SetMobilityModel(“ns3::RandomWalk2dMobilityModel”,

“Bounds”, RectangleValue(Rectangle(0, 100, 0, 100)));

mobility.Install(nodes);

// Install Internet stack and routing

InternetStackHelper internet;

internet.Install(nodes);

Ipv4AddressHelper address;

address.SetBase(“10.1.1.0”, “255.255.255.0”);

Ipv4InterfaceContainer interfaces = address.Assign(devices);

// Generate traffic

uint16_t port = 9;

UdpEchoServerHelper server(port);

ApplicationContainer serverApp = server.Install(nodes.Get(9)); // Node 9 as the server

serverApp.Start(Seconds(1.0));

serverApp.Stop(Seconds(10.0));

UdpEchoClientHelper client(interfaces.GetAddress(9), port);

client.SetAttribute(“MaxPackets”, UintegerValue(100));

client.SetAttribute(“Interval”, TimeValue(MilliSeconds(100)));

client.SetAttribute(“PacketSize”, UintegerValue(1024));

ApplicationContainer clientApp = client.Install(nodes.Get(0)); // Node 0 as the client

clientApp.Start(Seconds(2.0));

clientApp.Stop(Seconds(10.0));

// Install Flow Monitor

FlowMonitorHelper flowmonHelper;

Ptr<FlowMonitor> monitor = flowmonHelper.InstallAll();

// Schedule network load calculation

Simulator::Schedule(Seconds(10.0), &CalculateNetworkLoad, monitor, 10.0);

// Calculate Hop Count

AsciiTraceHelper ascii;

Ptr<OutputStreamWrapper> stream = ascii.CreateFileStream(“hopcount.tr”);

Ptr<Ipv4Route> route;

Simulator::Schedule(Seconds(10.0), &CalculateHopCount, stream, route);

Simulator::Run();

Simulator::Destroy();

return 0;

}

Explanation of the Script

1. Network Load:
   • FlowMonitor monitors the total bytes which are inherited, and throughput is determined in Mbps.
2. Hop Count:
   • Ipv4Route and the amount of devices on the route’s output, node offers the hop count.
3. Traffic Generation:
   • An UdpEchoClient transmits traffic to an UdpEchoServer.
4. Mobility:
   • Arbitrary mobility is integrated for replicating the dynamic network topology.

5. Run the Simulation

1. Build the script:

./waf –run “network-load-and-hop-count”

1. Monitor the records for network load and hop count values.

6. Analyze Results

• Impact of Node Count:
  • Maximize the volume of nodes for monitoring changes within network load and hop count.
• Impact of Traffic:
  • Enlarge packet rates or packet sizes to examining the network load effect of traffic.

We had expounded the comprehensive, stepwise guidance to implement the Network Load and Hop Count and analyse the outcomes in NS3 tool. More information will be shared in the forthcoming manual.