How to Implement Wireless Topology in ns3

To implement the wireless topology in ns3 wants to generate the network where nodes can communicate wirelessly like WiFi.

Below is the detailed guide on setup the basic wireless topology in ns3:

Step-by-Step Implementation

Step 1: Install ns3

• Make sure ns3 is installed in the computer.

Step 2: Create a New Simulation Script

• Create a new C++ script for your simulation.

Step 3: Include Necessary Headers

• In the script, include the necessary ns-3 headers:

#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”

Step 4: Set Up the Wireless Topology

By using numerous nodes we are setup the basic wireless topology in ns3:

using namespace ns3;

NS_LOG_COMPONENT_DEFINE (“WirelessTopology”);

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

{

// Configure command line parameters

CommandLine cmd;

cmd.Parse (argc, argv);

// Create nodes

NodeContainer wifiStaNodes;

wifiStaNodes.Create (4); // Create 4 STA (station) nodes

NodeContainer wifiApNode;

wifiApNode.Create (1); // Create 1 AP (access point) node

// Configure the wireless channel and PHY layer

YansWifiChannelHelper channel = YansWifiChannelHelper::Default ();

YansWifiPhyHelper phy = YansWifiPhyHelper::Default ();

phy.SetChannel (channel.Create ());

// Configure the WiFi standard and MAC layer

WifiHelper wifi;

wifi.SetRemoteStationManager (“ns3::AarfWifiManager”);

WifiMacHelper mac;

Ssid ssid = Ssid (“ns-3-ssid”);

mac.SetType (“ns3::StaWifiMac”,

“Ssid”, SsidValue (ssid),

“ActiveProbing”, BooleanValue (false));

NetDeviceContainer staDevices = wifi.Install (phy, mac, wifiStaNodes);

mac.SetType (“ns3::ApWifiMac”,

“Ssid”, SsidValue (ssid));

NetDeviceContainer apDevice = wifi.Install (phy, mac, wifiApNode);

// Install the internet stack

InternetStackHelper stack;

stack.Install (wifiApNode);

stack.Install (wifiStaNodes);

// Assign IP addresses to the devices

Ipv4AddressHelper address;

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

Ipv4InterfaceContainer staInterfaces = address.Assign (staDevices);

Ipv4InterfaceContainer apInterface = address.Assign (apDevice);

// Configure mobility

MobilityHelper mobility;

mobility.SetPositionAllocator (“ns3::GridPositionAllocator”,

“MinX”, DoubleValue (0.0),

“MinY”, DoubleValue (0.0),

“DeltaX”, DoubleValue (5.0),

“DeltaY”, DoubleValue (10.0),

“GridWidth”, UintegerValue (3),

“LayoutType”, StringValue (“RowFirst”));

mobility.SetMobilityModel (“ns3::RandomWalk2dMobilityModel”,

“Bounds”, RectangleValue (Rectangle (-50, 50, -50, 50)));

mobility.Install (wifiStaNodes);

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

mobility.Install (wifiApNode.Get (0));

// Set up applications (e.g., UDP echo server and client)

uint16_t port = 9; // Port number for applications

// Install UDP Echo Server on the AP node

UdpEchoServerHelper echoServer (port);

ApplicationContainer serverApps = echoServer.Install (wifiApNode.Get (0));

serverApps.Start (Seconds (1.0));

serverApps.Stop (Seconds (10.0));

// Install UDP Echo Clients on STA nodes to communicate with the AP

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

{

UdpEchoClientHelper echoClient (apInterface.GetAddress (0), port);

echoClient.SetAttribute (“MaxPackets”, UintegerValue (1));

echoClient.SetAttribute (“Interval”, TimeValue (Seconds (1.0)));

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

ApplicationContainer clientApps = echoClient.Install (wifiStaNodes.Get (i));

clientApps.Start (Seconds (2.0 + i)); // Stagger start times

clientApps.Stop (Seconds (10.0));

}

// Run simulation

Simulator::Stop (Seconds (10.0));

Simulator::Run ();

Simulator::Destroy ();

return 0;

}

Step 5: Build and Run the Simulation

1. Save the script as wireless-topology.cc.
2. Build the script using waf:

./waf configure –enable-examples

./waf build

1. Run the simulation:

./waf –run scratch/wireless-topology

 Explanation of the Script

• Node Creation: Creates four station (STA) nodes and one access point (AP) node.
• Wireless Channel and PHY Layer: Configures the wireless channel and PHY layer using YansWifiChannelHelper and YansWifiPhyHelper.
• WiFi Standard and MAC Layer: Configures the WiFi standard and MAC layer using WifiHelper and WifiMacHelper.
• Internet Stack: Installs the internet stack on all nodes.
• IP Addressing: Assigns IP addresses to the wireless devices.
• Mobility Model: Sets the position of nodes using GridPositionAllocator and configures mobility models for the STA nodes and AP node.
• Applications: Sets up a UDP echo server on the AP node and UDP echo clients on the STA nodes to demonstrate communication between nodes.

Here, we had implemented the wireless topology by creating the topology with numerous nodes in ns3 framework.

We understand that implementing Wireless Mesh Topology in ns3 can be challenging. If you need assistance, please don’t hesitate to contact us at ns3simulation.com. Our developers are here to help you achieve a successful outcome. Share your parameter details with us for networking performance, and get the best results. We also offer additional information on how wireless topology performs in other simulation tools.