To implement ring-mesh hybrid topology in ns3, we need to create a network where nodes are connected in both a ring topology and a mesh topology.
Here is a complete guide on implementing ring-mesh topology using ns3.
Steps for implementation
Step 1: Install ns-3
Make sure that ns3 is installed in the computer. If not, install it.
Step 2: Create a New Simulation Script
For your simulation, create a new C++ script.
Step 3: Include Necessary Headers
include the necessary ns3 headers in your script.
#include “ns3/core-module.h”
#include “ns3/network-module.h”
#include “ns3/internet-module.h”
#include “ns3/point-to-point-module.h”
#include “ns3/csma-module.h”
#include “ns3/mobility-module.h”
#include “ns3/applications-module.h”
Step 4: Set Up the Ring-Mesh Hybrid Topology
Below is an example to set up ring-mesh hybrid topology with six nodes.
using namespace ns3;
NS_LOG_COMPONENT_DEFINE (“RingMeshHybridTopology”);
int main (int argc, char *argv[])
{
// Configure command line parameters
CommandLine cmd;
cmd.Parse (argc, argv);
// Create nodes
NodeContainer nodes;
nodes.Create (6); // Create 6 nodes for the ring-mesh hybrid network
// Create point-to-point links to form a ring topology
PointToPointHelper pointToPoint;
pointToPoint.SetDeviceAttribute (“DataRate”, StringValue (“1Gbps”));
pointToPoint.SetChannelAttribute (“Delay”, StringValue (“2ms”));
NetDeviceContainer devices;
Ipv4AddressHelper address;
Ipv4InterfaceContainer interfaces;
for (uint32_t i = 0; i < nodes.GetN (); ++i)
{
NodeContainer pair (nodes.Get (i), nodes.Get ((i + 1) % nodes.GetN ()));
NetDeviceContainer devicePair = pointToPoint.Install (pair);
devices.Add (devicePair);
std::ostringstream subnet;
subnet << “10.1.” << i << “.0”;
address.SetBase (subnet.str ().c_str (), “255.255.255.0”);
interfaces.Add (address.Assign (devicePair));
}
// Create CSMA links to form a mesh topology among the nodes
CsmaHelper csma;
csma.SetChannelAttribute (“DataRate”, StringValue (“1Gbps”));
csma.SetChannelAttribute (“Delay”, TimeValue (NanoSeconds (6560)));
NetDeviceContainer meshDevices;
for (uint32_t i = 0; i < nodes.GetN (); ++i)
{
for (uint32_t j = i + 1; j < nodes.GetN (); ++j)
{
NodeContainer pair (nodes.Get (i), nodes.Get (j));
NetDeviceContainer devicePair = csma.Install (pair);
meshDevices.Add (devicePair);
std::ostringstream subnet;
subnet << “10.2.” << i << “.” << j << “.0”;
address.SetBase (subnet.str ().c_str (), “255.255.255.0”);
interfaces.Add (address.Assign (devicePair));
}
}
// Install the internet stack
InternetStackHelper stack;
stack.Install (nodes);
// Assign IP addresses to the ring and mesh devices
for (uint32_t i = 0; i < devices.GetN (); i += 2)
{
Ipv4AddressHelper ipv4;
std::ostringstream subnet;
subnet << “10.1.” << (i / 2 + 1) << “.0”;
ipv4.SetBase (subnet.str ().c_str (), “255.255.255.0”);
ipv4.Assign (NetDeviceContainer (devices.Get (i), devices.Get (i + 1)));
}
for (uint32_t i = 0; i < meshDevices.GetN (); i += 2)
{
Ipv4AddressHelper ipv4;
std::ostringstream subnet;
subnet << “10.2.” << (i / 2 + 1) << “.0”;
ipv4.SetBase (subnet.str ().c_str (), “255.255.255.0”);
ipv4.Assign (NetDeviceContainer (meshDevices.Get (i), meshDevices.Get (i + 1)));
}
// Set up mobility model (optional)
MobilityHelper mobility;
Ptr<ListPositionAllocator> positionAlloc = CreateObject<ListPositionAllocator> ();
positionAlloc->Add (Vector (50.0, 50.0, 0.0)); // Node 0 position
positionAlloc->Add (Vector (100.0, 50.0, 0.0)); // Node 1 position
positionAlloc->Add (Vector (150.0, 50.0, 0.0)); // Node 2 position
positionAlloc->Add (Vector (150.0, 100.0, 0.0)); // Node 3 position
positionAlloc->Add (Vector (100.0, 100.0, 0.0)); // Node 4 position
positionAlloc->Add (Vector (50.0, 100.0, 0.0)); // Node 5 position
mobility.SetPositionAllocator (positionAlloc);
mobility.SetMobilityModel (“ns3::ConstantPositionMobilityModel”);
mobility.Install (nodes);
// Set up applications (e.g., UDP echo server and client)
uint16_t port = 9; // Port number for applications
// Install UDP Echo Server on node 0
UdpEchoServerHelper echoServer (port);
ApplicationContainer serverApps = echoServer.Install (nodes.Get (0));
serverApps.Start (Seconds (1.0));
serverApps.Stop (Seconds (10.0));
// Install UDP Echo Clients on other nodes to communicate with node 0
for (uint32_t i = 1; i < nodes.GetN (); ++i)
{
UdpEchoClientHelper echoClient (interfaces.GetAddress (0), port);
echoClient.SetAttribute (“MaxPackets”, UintegerValue (1));
echoClient.SetAttribute (“Interval”, TimeValue (Seconds (1.0)));
echoClient.SetAttribute (“PacketSize”, UintegerValue (1024));
ApplicationContainer clientApps = echoClient.Install (nodes.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
Save the script as ring-mesh-hybrid-topology.cc and build the script using waf, then run the simulation.
./waf configure –enable-examples
./waf build
./waf –run scratch/ring-mesh-hybrid-topology
Explanation of the script
- Node Creation: For the ring-mesh hybrid network, creates six nodes.
- Point-to-Point Links: To form a ring topology among the nodes, configured point-to-point links.
- Internet Stack: On all nodes, installs the internet stack.
- IP Addressing: To both the ring and mesh devices, assigns IP addresses using different subnets.
- Mobility Model: using ListPositionAllocator and ConstantPositionMobilityModel, set the position of nodes in a specific layout.
- Applications: On node 0, sets up a UDP echo server and a UDP echo client on nodes to demonstrate communication.
Overall, we had a implementation on ring-mesh hybrid topology by creating a network where nodes are connected in both a ring topology and a mesh topology.
Share with us the specifics of your parameters, and we will assist you in conducting a performance analysis of networking Ring Mesh Hybrid Topology in NS3.