How To Implement Cognitive Ad Hoc Network in NS3

To implement a cognitive ad-hoc network (CAN) in ns-3 take in to simulate a network where nodes we must dynamically adapt to changes in the environment by choosing the superlative accessible communication channels. Cognitive Radio (CR) technology is frequently used for such networks. All types of Cognitive Radio (CR) technology programming are carried on by us.

Here is the step by procedures to set up a cognitive ad hoc network simulation in ns-3 environment.

Step-by-Step Guide to Implement Cognitive Ad-hoc Network in ns-3

1. Set Up Your Development Environment

1. Install ns-3:
   • Follow the official ns-3 installation guide.
2. Install Required Modules:
   • Ensure you have all necessary ns-3 modules installed, such as WiFi, Spectrum, and Mobility modules.

2. Create a Basic Cognitive Ad-hoc Network Simulation Script

Here is the sample script to set up a fundamentals CAN environment using the ns-3:

#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/spectrum-module.h”

#include “ns3/spectrum-wifi-helper.h”

using namespace ns3;

NS_LOG_COMPONENT_DEFINE (“CognitiveAdhocNetwork”);

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

{

  // Set simulation parameters

  uint32_t numNodes = 5;

  double simTime = 20.0; // Simulation time in seconds

  CommandLine cmd;

  cmd.AddValue(“numNodes”, “Number of nodes”, numNodes);

  cmd.AddValue(“simTime”, “Simulation time”, simTime);

  cmd.Parse(argc, argv);

  // Create nodes

  NodeContainer nodes;

  nodes.Create(numNodes);

  // Configure WiFi for cognitive communication

  SpectrumWifiPhyHelper wifiPhy = SpectrumWifiPhyHelper::Default();

  YansWifiChannelHelper wifiChannel = YansWifiChannelHelper::Default();

  wifiPhy.SetChannel(wifiChannel.Create());

  WifiMacHelper wifiMac;

  wifiMac.SetType(“ns3::AdhocWifiMac”);

  WifiHelper wifi;

  wifi.SetStandard(WIFI_PHY_STANDARD_80211a);

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

  // Install the Internet stack on nodes

  InternetStackHelper internet;

  internet.Install(nodes);

  // Assign IP addresses to devices

  Ipv4AddressHelper ipv4;

  ipv4.SetBase(“10.1.1.0”, “255.255.255.0”);

  Ipv4InterfaceContainer interfaces = ipv4.Assign(devices);

  // Set up mobility

  MobilityHelper mobility;

  Ptr<ListPositionAllocator> positionAlloc = CreateObject<ListPositionAllocator>();

  for (uint32_t i = 0; i < numNodes; ++i)

  {

    positionAlloc->Add(Vector(0.0, i * 20.0, 0.0));

  }

  mobility.SetPositionAllocator(positionAlloc);

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

  mobility.Install(nodes);

  // Install applications (e.g., UDP echo)

  uint16_t port = 9;

  UdpEchoServerHelper echoServer(port);

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

  serverApps.Start(Seconds(1.0));

  serverApps.Stop(Seconds(simTime));

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

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

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

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

  ApplicationContainer clientApps = echoClient.Install(nodes.Get(numNodes – 1));

  clientApps.Start(Seconds(2.0));

  clientApps.Stop(Seconds(simTime));

  // Enable tracing

  wifiPhy.EnablePcap(“cognitive-adhoc”, devices);

  // Run the simulation

  Simulator::Stop(Seconds(simTime));

  Simulator::Run();

  Simulator::Destroy();

  return 0;

}

Explanation of the Script

Here is the explanation for the script:

1. Include Necessary Headers:
   • Include headers for ns-3 core, network, internet, WiFi, mobility, applications, and spectrum modules.
2. Set Simulation Parameters:
   • Define the number of nodes and simulation time.
3. Create Nodes:
   • Create a container for the nodes.
4. Configure WiFi for Cognitive Communication:
   • Set up WiFi using the SpectrumWifiPhyHelper and configure the physical and MAC layers for ad-hoc communication.
5. Install Internet Stack:
   • Install the Internet stack on the nodes using InternetStackHelper.
6. Assign IP Addresses:
   • Assign IP addresses to the devices using Ipv4AddressHelper.
7. Set Up Mobility:
   • Define the positions and mobility models for the nodes using MobilityHelper.
8. Install Applications:
   • Install a simple UDP echo server on one node and a client on another node to demonstrate communication.
9. Enable Tracing:
   • Enable pcap tracing to capture packet traces for analysis.
10. Run the Simulation:
    • Set the simulation stop time, run the simulation, and clean up using Simulator::Stop, Simulator::Run, and Simulator::Destroy.

Further Enhancements

Here are the future improvements for the cognitive adhoc environment:

1. Dynamic Spectrum Access:
   • Implement algorithms for dynamic spectrum access, allowing nodes to sense and select the best available channels.
2. Routing Protocols:
   • Implement and evaluate different ad-hoc routing protocols such as AODV, DSDV, or OLSR.
3. Network Performance Metrics:
   • Collect and analyze performance metrics such as throughput, latency, packet delivery ratio, and network overhead.
4. Advanced Mobility Models:
   • Implement more realistic mobility models, such as waypoint-based models or models based on real movement patterns.
5. Cognitive Radio Algorithms:
   • Implement cognitive radio algorithms for spectrum sensing, decision-making, and adaptation.
6. Fault Tolerance and Resilience:
   • Implement and evaluate fault tolerance mechanisms and resilience strategies for network communication.

We have discussed here about the implementation procedures, process and their future improvements for the cognitive ad hoc network in ns3 environment and also support all kinds of ad hoc network projects.