How to Start Ring Topology Projects Using NS3

To start a Ring Topology project using NS3 that requires making a network in which nodes are linked within a circular manner including each node are associated to precisely two other nodes. Following is a step-by-step guide how we can configure and replicate a ring topology using NS3:

Steps to Start Ring Topology Projects in NS3

Step 1: Set Up NS3

  1. Install NS3: Be presence of NS3 website to download NS3 and then we adhere to the installation guidance.
  2. Verify Installation: We execute a sample script to make sure that NS3 is properly operating:

./waf –run scratch/my_first

Step 2: Understand Ring Topology

  • Ring Topology:
    • This topology every single node links to its two neighbors to generate a closed loop.
    • Information can be moved within one or both directions over the ring.

Step 3: Plan Your Simulation

Choose the following:

  • Number of Nodes: We can define how many nodes the ring will be included.
  • Traffic Patterns: We try to find the interaction among the nodes.
  • Metrics: Estimate the performance indicators such as throughput, delay, and packet loss.

Step 4: Create the Ring Topology

  1. Define Nodes: Make use of NodeContainer to generate the nodes.

NodeContainer nodes;

uint32_t numNodes = 6; // Number of nodes in the ring

nodes.Create(numNodes);

  1. Connect Nodes with Point-to-Point Links: We associate the nodes within a ring with the support of PointToPointHelper.

PointToPointHelper p2p;

p2p.SetDeviceAttribute(“DataRate”, StringValue(“100Mbps”));

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

NetDeviceContainer devices;

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

NetDeviceContainer link = p2p.Install(nodes.Get(i), nodes.Get((i + 1) % numNodes));

devices.Add(link);

}

  1. Install Internet Stack: We should install the internet protocol stack at every node.

InternetStackHelper stack;

stack.Install(nodes);

  1. Assign IP Addresses: In the links to allocate unique IP address.

Ipv4AddressHelper address;

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

std::ostringstream subnet;

subnet << “10.1.” << i + 1 << “.0”;

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

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

}

Step 5: Set Up Applications

  1. Install Traffic Generators: We configure the applications to utilize like UdpEchoServer and UdpEchoClient replicating the traffic.

Server:

UdpEchoServerHelper echoServer(9);

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

serverApp.Start(Seconds(1.0));

serverApp.Stop(Seconds(10.0));

Clients: We need to install client applications on other nodes interacting with the server.

for (uint32_t i = 1; i < numNodes; ++i) {

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(i));

clientApp.Start(Seconds(2.0));

clientApp.Stop(Seconds(10.0));

}

Step 6: Simulate and Analyze

  1. Run the Simulation: We execute the simulation using below command.

Simulator::Run();

Simulator::Destroy();

  1. Capture Packets: Allow packets to seize using .pcap files for analysis.

p2p.EnablePcap(“ring_topology”, devices, true);

  1. Trace Logs: For debugging, enable the logging framework of NS3:

export NS_LOG=”UdpEchoClientApplication=level_all|prefix_func”

./waf –run scratch/ring_topology

Step 7: Enhance the Simulation

  • Launch link failures to observe the resilience.
  • Make use of various traffic patterns such as FTP and HTTP.
  • Next, we compute the performance parameters such as delay, jitter, and throughput.

Example: Minimal NS3 Script for Ring 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 numNodes = 6;

NodeContainer nodes;

nodes.Create(numNodes);

PointToPointHelper p2p;

p2p.SetDeviceAttribute(“DataRate”, StringValue(“100Mbps”));

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

NetDeviceContainer devices;

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

NetDeviceContainer link = p2p.Install(nodes.Get(i), nodes.Get((i + 1) % numNodes));

devices.Add(link);

}

InternetStackHelper stack;

stack.Install(nodes);

Ipv4AddressHelper address;

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

std::ostringstream subnet;

subnet << “10.1.” << i + 1 << “.0”;

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

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

}

UdpEchoServerHelper echoServer(9);

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

serverApp.Start(Seconds(1.0));

serverApp.Stop(Seconds(10.0));

for (uint32_t i = 1; i < numNodes; ++i) {

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(i));

clientApp.Start(Seconds(2.0));

clientApp.Stop(Seconds(10.0));

}

p2p.EnablePcap(“ring_topology”, devices, true);

Simulator::Run();

Simulator::Destroy();

return 0;

}

We should save the script as ring_topology.cc, and then we compile and execute it:

./waf –run ring_topology

Next Steps

  • Utilize NetAnim to envision the topology.
  • Test with bi-directional interaction and then estimate the parameters.
  • We should equate the ring topology including other topologies like star, bus topology for performance.

This comprehensive simulation process for replicating and analysing the Ring Topology projects has been effectively conducted using NS3 tool, with comprehensive details to follow in another manual.

Let’s kick off your Ring Topology Projects with NS3! We’ll run simulations tailored to your needs and be there to help you every step of the way to make sure your project wraps up successfully.