How to Start Grid Topology Projects Using NS3

To start Grid Topology in NS3 that needs to organize the nodes within a grid-like structure in which each node associates to their neighbouring nodes such as north, south, east, and west. It is typically utilized within wireless sensor networks, mesh networks, and other distributed systems. Send us a message we guide you with best project performance and simulation results.  Below is a stepwise guide to start and simulate the Grid Topology Projects using NS3.

Steps to Start Grid Topology Project in NS3

Step 1: Set Up NS3

  1. Install NS3:
    • Be present at NS3 webpage to download NS3 on the system.
    • We stick to the installation guidance.
  2. Verify Installation: Make sure that NS3 is properly installed including a simple example:

./waf –run scratch/my_first

Step 2: Understand Grid Topology

  • Grid Topology:
    • In a 2D grid pattern, nodes are located.
    • Each node associates to their neighbouring nodes in terms of up, down, left, right.
    • Make use of grid topology generally in scenarios like IoT, wireless sensor networks, and data center layouts.

Step 3: Plan the Topology

  1. Define the grid size:
    • For instance, we can delineate the grid size like 3×33 \times 33×3 grid in 9 nodes.
  2. Set simulation goals:
    • The simulation objects are to replicate the interaction among the nodes.
    • Then, we estimate the performance indicators such as delay, throughput, and packet loss in this topology.

Step 4: Set Up the Grid Topology

  1. Create Nodes: In the network, we delineate the nodes.

NodeContainer nodes;

uint32_t rows = 3, cols = 3; // Grid dimensions

uint32_t numNodes = rows * cols;

nodes.Create(numNodes);

  1. Set Up Point-to-Point Links: Describe link properties exploiting PointToPointHelper.

PointToPointHelper p2p;

p2p.SetDeviceAttribute(“DataRate”, StringValue(“10Mbps”));

p2p.SetChannelAttribute(“Delay”, StringValue(“2ms”));

  1. Connect Nodes in a Grid: In grid topology, we can associate each node to their neighbouring nodes.

NetDeviceContainer devices;

for (uint32_t i = 0; i < rows; ++i) {

for (uint32_t j = 0; j < cols; ++j) {

uint32_t currentNode = i * cols + j;

// Connect to the right neighbor

if (j < cols – 1) {

uint32_t rightNode = currentNode + 1;

NetDeviceContainer link = p2p.Install(nodes.Get(currentNode), nodes.Get(rightNode));

devices.Add(link);

}

// Connect to the bottom neighbor

if (i < rows – 1) {

uint32_t bottomNode = currentNode + cols;

NetDeviceContainer link = p2p.Install(nodes.Get(currentNode), nodes.Get(bottomNode));

devices.Add(link);

}

}

}

  1. Install Internet Stack: We need to insert the Internet stack to every node.

InternetStackHelper stack;

stack.Install(nodes);

  1. Assign IP Addresses: In each link to allocate distinct IP address.

Ipv4AddressHelper address;

uint32_t subnetIndex = 1;

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

std::ostringstream subnet;

subnet << “10.1.” << subnetIndex++ << “.0”;

address.SetBase(subnet.str().c_str(), “255.255.255.0”);

address.Assign(devices.Get(i));

}

Step 5: Set Up Applications

  1. Server Application: Set a UDP echo server at one of the corner nodes of grid.

UdpEchoServerHelper echoServer(9); // Port 9

ApplicationContainer serverApp = echoServer.Install(nodes.Get(numNodes – 1)); // Bottom-right corner

serverApp.Start(Seconds(1.0));

serverApp.Stop(Seconds(10.0));

  1. Client Applications: We can install UDP echo clients on the other corner nodes interacting with the server.

UdpEchoClientHelper echoClient(Ipv4Address(“10.1.1.1”), 9); // Server’s IP

echoClient.SetAttribute(“MaxPackets”, UintegerValue(10));

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

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

ApplicationContainer clientApp = echoClient.Install(nodes.Get(0)); // Top-left corner

clientApp.Start(Seconds(2.0));

clientApp.Stop(Seconds(10.0));

Step 6: Run and Analyze

  1. Run the Simulation: Now, we execute the simulation with the support of following code.

Simulator::Run();

Simulator::Destroy();

  1. Enable Packet Capture: Allow packet to seize traffic for analysis with .pcap files.

p2p.EnablePcapAll(“grid_topology”);

  1. Trace Logs: We can utilize NS3 logging for debugging:

export NS_LOG=”UdpEchoClientApplication=level_all|prefix_func”

./waf –run scratch/grid_topology

Example: Minimal NS3 Script for Grid Topology

#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”

using namespace ns3;

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

uint32_t rows = 3, cols = 3;

uint32_t numNodes = rows * cols;

// Create nodes

NodeContainer nodes;

nodes.Create(numNodes);

// Set up Point-to-Point links

PointToPointHelper p2p;

p2p.SetDeviceAttribute(“DataRate”, StringValue(“10Mbps”));

p2p.SetChannelAttribute(“Delay”, StringValue(“2ms”));

// Connect nodes in a grid

NetDeviceContainer devices;

for (uint32_t i = 0; i < rows; ++i) {

for (uint32_t j = 0; j < cols; ++j) {

uint32_t currentNode = i * cols + j;

// Connect to the right neighbor

if (j < cols – 1) {

uint32_t rightNode = currentNode + 1;

NetDeviceContainer link = p2p.Install(nodes.Get(currentNode), nodes.Get(rightNode));

devices.Add(link);

}

// Connect to the bottom neighbor

if (i < rows – 1) {

uint32_t bottomNode = currentNode + cols;

NetDeviceContainer link = p2p.Install(nodes.Get(currentNode), nodes.Get(bottomNode));

devices.Add(link);

}

}

}

// Install Internet stack

InternetStackHelper stack;

stack.Install(nodes);

// Assign IP addresses

Ipv4AddressHelper address;

uint32_t subnetIndex = 1;

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

std::ostringstream subnet;

subnet << “10.1.” << subnetIndex++ << “.0”;

address.SetBase(subnet.str().c_str(), “255.255.255.0”);

address.Assign(devices.Get(i));

}

// Set up UDP echo server on the last node

UdpEchoServerHelper echoServer(9);

ApplicationContainer serverApp = echoServer.Install(nodes.Get(numNodes – 1));

serverApp.Start(Seconds(1.0));

serverApp.Stop(Seconds(10.0));

// Set up UDP echo client on the first node

UdpEchoClientHelper echoClient(Ipv4Address(“10.1.1.1”), 9);

echoClient.SetAttribute(“MaxPackets”, UintegerValue(10));

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

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

ApplicationContainer clientApp = echoClient.Install(nodes.Get(0));

clientApp.Start(Seconds(2.0));

clientApp.Stop(Seconds(10.0));

// Enable packet capture

p2p.EnablePcapAll(“grid_topology”);

// Run the simulation

Simulator::Run();

Simulator::Destroy();

return 0;

}

Step 7: Compile and Run

  1. We should store the script like grid_topology.cc.
  2. Then, we compile and execute it:

./waf –run grid_topology

Step 8: Enhance the Simulation

  • Experiment with Traffic Models:
    • Make use of TCP rather than UDP.
    • To mimic traffic models like FTP or HTTP traffic.
  • Analyze Performance:
    • We need to assess the performance indicators such as throughput, delay, and jitter.
  • Simulate Failures:
    • Detach certain nodes or links learning the fault tolerance.
  • Visualize:
    • Afterward, envision the grid topology and traffic flow to utilize NetAnim tool.

These projects outline follows a structured sequence for simulating, analysing and visualizing the Grid Topology projects using NS3 simulation tool and we are ready to provide more detailed insights based on your requirements.