How to Start Heterogeneous Networks Projects Using NS3

To start a Heterogeneous Network (HetNet) project using NS3, we will be replicating networks including diverse kinds of access technologies like LTE, WiFi, and 5G operating together offering the seamless connectivity. LTE and WiFi modules of NS3 permits to replicate a HetNet environment according to the factors such as signal strength, data rates, or congestion, User Equipment (UE) devices can change or be offloaded to diverse networks.

Following is a basic approach to setting up and running a HetNet project in NS3.

Steps to Start Heterogeneous Networks (HetNet) Projects in NS-3

  1. Install NS3 with LTE and WiFi Modules

Make certain that NS3 is installed including both LTE and WiFi modules are allowed.

  1. Download and Install NS3 (if not already done).

git clone https://gitlab.com/nsnam/ns-3-dev.git ns-3

cd ns-3

./waf configure –enable-examples –enable-tests

./waf build

  1. Verify LTE and WiFi Modules: Make sure that LTE and WiFi examples properly executed. For instance:

./waf –run=lte-epc-simple

./waf –run=wifi-simple-infra

  1. Understand Heterogeneous Network (HetNet) Components

In a HetNet, we will function with:

  • Macro Cells (LTE eNodeBs): These offer the cellular coverage that normally for LTE or 5G.
  • Small Cells (WiFi APs): These offload data traffic from LTE within high-density areas, minimizing congestion and maximize capacity.
  • User Equipment (UE): Mobile devices, which can be linked to both LTE and WiFi networks.
  • Core Network (EPC): For LTE, it offers the backbone and manages the connections to the internet or other external networks.
  1. Set Up the Basic HetNet Topology with LTE and WiFi

In this instance, we will make a basic HetNet topology in which depends on the availability UEs can associate to either LTE or WiFi.

Example Setup: LTE Macro Cell with WiFi Small Cell for Offloading

  1. Define the Nodes: For the LTE eNodeB, WiFi AP, and UEs, we make nodes.
  2. Set Up LTE and WiFi Networks: Set up the networks utilizing NS3’s LTE and WiFi helpers.
  3. Assign Mobility Models: Describe the UE’s movement replicating a realistic HetNet environment.

Here’s a simple script configuring the LTE and WiFi with UEs, which can be associated to both networks:

#include “ns3/core-module.h”

#include “ns3/network-module.h”

#include “ns3/mobility-module.h”

#include “ns3/internet-module.h”

#include “ns3/lte-module.h”

#include “ns3/wifi-module.h”

#include “ns3/applications-module.h”

using namespace ns3;

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

CommandLine cmd;

cmd.Parse(argc, argv);

// Create LTE Helper and EPC Helper

Ptr<LteHelper> lteHelper = CreateObject<LteHelper>();

Ptr<PointToPointEpcHelper> epcHelper = CreateObject<PointToPointEpcHelper>();

lteHelper->SetEpcHelper(epcHelper);

// Create nodes: eNodeB, WiFi AP, and UEs

NodeContainer enbNodes;

enbNodes.Create(1); // LTE Macro Cell

NodeContainer wifiApNode;

wifiApNode.Create(1); // WiFi Small Cell

NodeContainer ueNodes;

ueNodes.Create(3); // Three UEs

// Install LTE Devices on eNodeB and UEs

NetDeviceContainer enbLteDevs = lteHelper->InstallEnbDevice(enbNodes);

NetDeviceContainer ueLteDevs = lteHelper->InstallUeDevice(ueNodes);

// Install WiFi devices on WiFi AP and UEs

WifiHelper wifiHelper;

wifiHelper.SetStandard(WIFI_PHY_STANDARD_80211ac);

YansWifiPhyHelper wifiPhy = YansWifiPhyHelper::Default();

YansWifiChannelHelper wifiChannel = YansWifiChannelHelper::Default();

wifiPhy.SetChannel(wifiChannel.Create());

WifiMacHelper wifiMac;

Ssid ssid = Ssid(“ns3-wifi”);

wifiMac.SetType(“ns3::ApWifiMac”, “Ssid”, SsidValue(ssid));

NetDeviceContainer apDevices = wifiHelper.Install(wifiPhy, wifiMac, wifiApNode);

wifiMac.SetType(“ns3::StaWifiMac”, “Ssid”, SsidValue(ssid));

NetDeviceContainer staDevices = wifiHelper.Install(wifiPhy, wifiMac, ueNodes);

// Install Internet stack on UEs

InternetStackHelper internet;

internet.Install(ueNodes);

internet.Install(wifiApNode);

// Assign IP addresses to WiFi and LTE interfaces

Ipv4AddressHelper address;

Ipv4InterfaceContainer wifiInterfaces;

address.SetBase(“192.168.1.0”, “255.255.255.0”);

wifiInterfaces = address.Assign(staDevices);

address.Assign(apDevices);

Ipv4InterfaceContainer ueIpIface = epcHelper->AssignUeIpv4Address(NetDeviceContainer(ueLteDevs));

for (uint32_t i = 0; i < ueNodes.GetN(); ++i) {

Ptr<Node> ueNode = ueNodes.Get(i);

Ptr<Ipv4StaticRouting> ueStaticRouting = Ipv4RoutingHelper::GetRouting<Ipv4StaticRouting>(ueNode->GetObject<Ipv4>()->GetRoutingProtocol());

ueStaticRouting->SetDefaultRoute(epcHelper->GetUeDefaultGatewayAddress(), 1);

}

// Attach UEs to LTE and WiFi

for (uint32_t i = 0; i < ueNodes.GetN(); ++i) {

lteHelper->Attach(ueLteDevs.Get(i), enbLteDevs.Get(0)); // Attach to LTE initially

}

// Set up Mobility

MobilityHelper mobility;

mobility.SetMobilityModel(“ns3::ConstantPositionMobilityModel”);

mobility.Install(enbNodes);

mobility.Install(wifiApNode);

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(ueNodes);

// Install and configure a UDP application on each UE to generate traffic

uint16_t port = 1234;

UdpServerHelper server(port);

ApplicationContainer serverApps = server.Install(ueNodes);

serverApps.Start(Seconds(1.0));

serverApps.Stop(Seconds(10.0));

UdpClientHelper client(wifiInterfaces.GetAddress(0), port);

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

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

ApplicationContainer clientApps = client.Install(ueNodes);

clientApps.Start(Seconds(2.0));

clientApps.Stop(Seconds(10.0));

Simulator::Stop(Seconds(10.0));

Simulator::Run();

Simulator::Destroy();

return 0;

}

  1. Implement Offloading and Handover Logic

Execute the offloading mechanisms, which send UEs from LTE to WiFi and vice versa for a more realistic HetNet simulation. Handle the handovers, or execute a custom logic utilizing NS-3’s helper classes depends on the factors such as:

  • Signal Strength: Estimate the RSSI or RSRP and cause handover once a stronger signal is obtainable.
  • Data Rate: Offload UEs to WiFi once LTE is filled up to equalize the load.
  1. Monitor and Collect Performance Metrics

We estimate the HetNet simulation, to gather performance parameters like:

  • Throughput: Assess the data rate on both LTE and WiFi links.
  • Latency: We can monitor the end-to-end delay at each network for traffic.
  • Handover Latency: Evaluate the duration for a handover to accomplish.
  • Packet Loss: During handovers, find how much data is failed or by reason of congestion.

Example with FlowMonitor:

FlowMonitorHelper flowmon;

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

monitor->SerializeToXmlFile(“hetnet-flowmon.xml”, true, true);

  1. Experiment with Different Network Configurations

Test with diverse metrics discovering the distinct HetNet scenarios:

  • Increase the Number of UEs and APs: Focus on how scalability impacts the performance.
  • Adjust Network Conditions: Modify data rates, delays, and interference levels to replicate diverse environments.
  • Mobility Models: Mimic real-world situations utilizing diverse mobility patterns like pedestrian, vehicle-based.
  1. Visualize and Analyze Results
  • NetAnim: Envision the movement of UEs and handover events within real-time to utilize NS-3’s NetAnim tool.
  • Trace Files: For in-depth analysis of handovers, throughput, and latency using the generated trace files.
  • Plotting Tools: Transfer data plotting parameters such as handover delay, throughput, and packet loss.

By utilizing the NS3, we had effectively configured and executed the Heterogeneous Networks Projects and visualized the results through above following steps. We will be offer more details related this project in another manual.

To initiate the Heterogeneous Networks Projects utilizing the NS3 tool, you may depend on our specialists who offer exceptional guidance and deliver comprehensive project performance presentations. Therefore, do not hesitate to send us all your research details for further assistance. We manage the LTE and WiFi modules of NS3 effectively.