How to Calculate Network Load Balancing in ns3

To calculate network load balance in ns3, we need to measure how evenly the traffic is distributed throughout the network. We can achieve this by analyzing the traffic load on different links or nodes and comparing the distribution.

Here is a interesting guide to calculate network load balance in ns3.

Steps for calculating network gateways

1. Set up the simulation :

• Make sure that ns3 is installed in the computer. If not, install it and include necessary modules.

2. Define Network Topology:

• Define the network topology by incorporating nodes and links.

3. Configure Applications:

• On the nodes, setup applications to generate and receive traffic.

4. Monitor Traffic Load:

• To monitor amount of traffic on each link or node, use trace sources or callbacks.

5. Calculate Load Balancing:

• To determine the balance of the load across the network, calculate the load on each link or node.

Example code

Here is an example to set up a basic simulation to calculate load balancing by measuring the traffic load on each link in a point-to-point network in ns3.

#include “ns3/core-module.h”

#include “ns3/network-module.h”

#include “ns3/internet-module.h”

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

#include “ns3/applications-module.h”

#include “ns3/flow-monitor-module.h”

using namespace ns3;

NS_LOG_COMPONENT_DEFINE (“LoadBalancingExample”);

std::map<uint32_t, uint64_t> bytesReceived;

void RxTrace (Ptr<const Packet> packet, const Address &address)

{

Ptr<Node> node = DynamicCast<Node> (address);

bytesReceived[node->GetId ()] += packet->GetSize ();

}

void CalculateLoadBalancing (NodeContainer nodes)

{

uint64_t totalBytes = 0;

for (auto it = bytesReceived.begin (); it != bytesReceived.end (); ++it)

{

totalBytes += it->second;

}

double averageLoad = static_cast<double> (totalBytes) / nodes.GetN ();

NS_LOG_UNCOND (“Average Load: ” << averageLoad << ” bytes”);

double loadVariance = 0.0;

for (auto it = bytesReceived.begin (); it != bytesReceived.end (); ++it)

{

double deviation = it->second – averageLoad;

loadVariance += deviation * deviation;

}

loadVariance /= nodes.GetN ();

double loadStdDev = sqrt (loadVariance);

NS_LOG_UNCOND (“Load Standard Deviation: ” << loadStdDev);

}

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

{

CommandLine cmd;

uint32_t nNodes = 4;

cmd.AddValue (“nNodes”, “Number of nodes to simulate”, nNodes);

cmd.Parse (argc, argv);

Time::SetResolution (Time::NS);

NodeContainer nodes;

nodes.Create (nNodes);

PointToPointHelper pointToPoint;

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

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

InternetStackHelper stack;

stack.Install (nodes);

Ipv4AddressHelper address;

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

NetDeviceContainer devices;

for (uint32_t i = 0; i < nodes.GetN () – 1; ++i)

{

for (uint32_t j = i + 1; j < nodes.GetN (); ++j)

{

NetDeviceContainer linkDevices = pointToPoint.Install (NodeContainer (nodes.Get (i), nodes.Get (j)));

devices.Add (linkDevices);

address.Assign (linkDevices);

address.NewNetwork ();

}

}

// Create UDP applications

for (uint32_t i = 0; i < nNodes – 1; ++i)

{

UdpServerHelper server (9);

ApplicationContainer serverApp = server.Install (nodes.Get (i));

serverApp.Start (Seconds (1.0));

serverApp.Stop (Seconds (10.0));

UdpClientHelper client (Ipv4Address::GetAny (), 9);

client.SetAttribute (“MaxPackets”, UintegerValue (1000));

client.SetAttribute (“Interval”, TimeValue (MilliSeconds (10)));

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

ApplicationContainer clientApp = client.Install (nodes.Get (i + 1));

clientApp.Start (Seconds (2.0));

clientApp.Stop (Seconds (10.0));

}

// Trace received packets

Config::Connect (“/NodeList/*/DeviceList/*/MacRx”, MakeCallback (&RxTrace));

Simulator::Stop (Seconds (11.0));

Simulator::Run ();

CalculateLoadBalancing (nodes);

Simulator::Destroy ();

return 0;

}

Explanation

1. Setup:

Created multiple nodes and those nodes are connected by point-to-point links.

1. Applications:

To generate traffic, a UDP server and client are installed.

1. Traffic Monitoring:

To capture the amount of traffic received by each node, the RxTrace function is used.

1. CalculateLoadBalancing function:

This function calculates the average load and the standard deviation of the load to determine the load balancing.

Running the Simulation

Compile and run the simulation using the following commands :

./waf configure

./waf build

./waf –run your-script-name

Replace your-script-name with the actual name of your script file.

Totally, we had our simulation results on calculating network load balance in ns3 by measuring how evenly the traffic is distributed across the network. Also, we provide more detailed explanation on Network Load Balance.We conduct  networking comparison analysis for your projects. Please provide us with all the details of your parameters, and we will assist you in achieving the best results when calculating network load balancing in ns3simulation.