How to Implement Partial Mesh Topology in ns3

To implement a partial mesh topology in ns3, we need to create a network in which a fully connected mesh and a simpler topology are collaborately connected like a star or ring. In this network where not all nodes are directly connected to every other node, but some nodes are interconnected. The following steps will guide on how to implement partial Mesh Topology in ns3.

Steps to Implement a Partial Mesh Topology in NS3

1. Set Up the NS-3 Environment:
   • Make sure that NS3 is installed and properly configured.
2. Create the Nodes:
   • Create a set of nodes to represent the devices in the partial mesh network.
3. Set Up the Point-to-Point Channels:
   • Use point-to-point helpers to connect some of the nodes to form a partial mesh.
4. Install Network Stack:
   • Install the internet stack on all nodes.
5. Assign IP Addresses:
   • Assign IP addresses to the nodes connected by the point-to-point links.
6. Set Up Applications:
   • Install applications to generate traffic and demonstrate communication between nodes.

Example Code

Here is an example script to set up a simple partial mesh topology in ns3:

#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;

NS_LOG_COMPONENT_DEFINE (“PartialMeshTopologyExample”);

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

{

CommandLine cmd;

cmd.Parse (argc, argv);

// Create nodes

NodeContainer nodes;

nodes.Create (6); // Create 6 nodes for the partial mesh network

// Create point-to-point links

PointToPointHelper pointToPoint;

pointToPoint.SetDeviceAttribute (“DataRate”, StringValue (“5Mbps”));

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

InternetStackHelper stack;

stack.Install (nodes);

Ipv4AddressHelper address;

int subnet = 1;

// Connect some of the nodes to form a partial mesh

auto connectNodes = [&](uint32_t n1, uint32_t n2) {

NetDeviceContainer devices;

devices = pointToPoint.Install (NodeContainer (nodes.Get (n1), nodes.Get (n2)));

std::ostringstream subnetStream;

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

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

address.Assign (devices);

};

// Example connections for a partial mesh topology

connectNodes(0, 1);

connectNodes(0, 2);

connectNodes(1, 3);

connectNodes(2, 3);

connectNodes(3, 4);

connectNodes(4, 5);

connectNodes(2, 5);

// Enable routing

Ipv4GlobalRoutingHelper::PopulateRoutingTables ();

// Create a UDP server on node 5

UdpServerHelper udpServer (9);

ApplicationContainer serverApp = udpServer.Install (nodes.Get (5));

serverApp.Start (Seconds (1.0));

serverApp.Stop (Seconds (10.0));

// Create a UDP client on node 0

UdpClientHelper udpClient (Ipv4Address (“10.1.7.2”), 9); // Assuming node 5’s IP is 10.1.7.2

udpClient.SetAttribute (“MaxPackets”, UintegerValue (320));

udpClient.SetAttribute (“Interval”, TimeValue (MilliSeconds (50)));

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

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

clientApp.Start (Seconds (2.0));

clientApp.Stop (Seconds (10.0));

// Enable packet capture

pointToPoint.EnablePcapAll (“partial-mesh-topology”);

// Enable logging

LogComponentEnable (“UdpClient”, LOG_LEVEL_INFO);

LogComponentEnable (“UdpServer”, LOG_LEVEL_INFO);

Simulator::Run ();

Simulator::Destroy ();

return 0;

}

Explanation

1. Setup: The code sets up a partial mesh topology with six nodes connected by point-to-point links.
2. Point-to-Point Links: Point-to-point links are created to connect some of the nodes, forming a partial mesh. The data rate and delay are configured for the links.
3. Network Stack: The internet stack is installed on all nodes.
4. IP Addresses: IP addresses are assigned to the nodes connected by the point-to-point links.
5. Applications: A UDP server is installed on one of the nodes (node 5), and a UDP client is installed on another node (node 0) to generate traffic and demonstrate communication.
6. Packet Capture: Packet capture is enabled for the point-to-point links to observe network traffic.
7. Logging: Logging is enabled for the UDP client and server applications to provide detailed output during the simulation.

Running the Simulation

Compile and run the simulation using the following commands in ns3 environment:

./waf configure

./waf build

./waf –run partial-mesh-topology-example

Replace partial-mesh-topology-example with the actual name of the script file.

Overall, we all get to know how to implement Partial Mesh Topology in ns3 by creating a network that compromise between fully connected mesh and simpler topology like a Star or Ring.

The utilization of a Partial Mesh Topology in ns3, which is linked to a mesh and a less complex topology relevant to your project, can be received from ns3simulation.com.