How to Calculate Network Bridging in ns3

To calculate the network bridging in ns3, it encompasses to setup a network with bridges or switches and to computing how well it manage the traffic. Network bridges are used to connect with diverse segments of networks that permit them an interaction with each other. Here is the step by procedures on how to achieve this in ns3:

Steps to Calculate Network Bridging

1. Set Up the ns3 Environment:
   • Make sure ns3 is installed in the computer.
2. Define the Network Topology:
   • Create a network topology that includes bridges to connect different network segments.
3. Configure Bridges:
   • Use ns3 bridge helper to configure bridges in the network.
4. Install Applications:
   • Install traffic-generating applications on the nodes to simulate network traffic.
5. Monitor Performance Metrics:
   • Use trace sources or callbacks to monitor performance metrics such as throughput, latency, and packet loss.
6. Analyze Bridging Performance:
   • Calculate metrics such as throughput, latency, and packet loss to evaluate the performance of the network bridges.

Example Code

The given below is a sample on how to setup a basic ns3 simulation to estimate the performance of network bridge in a bridged LAN.

#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”

#include “ns3/bridge-module.h”

#include “ns3/flow-monitor-module.h”

using namespace ns3;

NS_LOG_COMPONENT_DEFINE (“NetworkBridgingExample”);

void CalculateBridgingPerformance (Ptr<FlowMonitor> flowMonitor, FlowMonitorHelper &flowHelper)

{

Ptr<Ipv4FlowClassifier> classifier = DynamicCast<Ipv4FlowClassifier> (flowHelper.GetClassifier ());

std::map<FlowId, FlowMonitor::FlowStats> stats = flowMonitor->GetFlowStats ();

double totalThroughput = 0.0;

double totalLatency = 0.0;

uint32_t totalPackets = 0;

uint32_t lostPackets = 0;

for (auto it = stats.begin (); it != stats.end (); ++it)

{

Ipv4FlowClassifier::FiveTuple t = classifier->FindFlow (it->first);

double throughput = it->second.rxBytes * 8.0 / (it->second.timeLastRxPacket.GetSeconds () – it->second.timeFirstTxPacket.GetSeconds ()) / 1024; // kbps

double latency = it->second.delaySum.GetSeconds () / it->second.rxPackets * 1000; // ms

uint32_t packets = it->second.rxPackets + it->second.lostPackets;

totalThroughput += throughput;

totalLatency += latency;

totalPackets += packets;

lostPackets += it->second.lostPackets;

}

double averageLatency = totalPackets > 0 ? totalLatency / stats.size () : 0;

double packetLoss = totalPackets > 0 ? (static_cast<double> (lostPackets) / totalPackets) * 100 : 0;

NS_LOG_UNCOND (“Total Throughput: ” << totalThroughput << ” kbps”);

NS_LOG_UNCOND (“Average Latency: ” << averageLatency << ” ms”);

NS_LOG_UNCOND (“Packet Loss: ” << packetLoss << ” %”);

}

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

{

CommandLine cmd;

cmd.Parse (argc, argv);

Time::SetResolution (Time::NS);

NodeContainer lanNodes;

lanNodes.Create (6);

NodeContainer routerNode;

routerNode.Create (1);

// Create point-to-point links between the router and the LAN segments

PointToPointHelper pointToPoint;

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

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

NetDeviceContainer p2pDevices1;

p2pDevices1 = pointToPoint.Install (routerNode.Get (0), lanNodes.Get (0));

NetDeviceContainer p2pDevices2;

p2pDevices2 = pointToPoint.Install (routerNode.Get (0), lanNodes.Get (1));

// Create LAN segments

CsmaHelper csma;

csma.SetChannelAttribute (“DataRate”, StringValue (“100Mbps”));

csma.SetChannelAttribute (“Delay”, TimeValue (NanoSeconds (6560)));

NetDeviceContainer csmaDevices1;

csmaDevices1 = csma.Install (NodeContainer (lanNodes.Get (2), lanNodes.Get (3)));

NetDeviceContainer csmaDevices2;

csmaDevices2 = csma.Install (NodeContainer (lanNodes.Get (4), lanNodes.Get (5)));

// Create bridge devices

BridgeHelper bridge;

NetDeviceContainer bridgeDevices1 = bridge.Install (lanNodes.Get (0), NetDeviceContainer (p2pDevices1.Get (1), csmaDevices1.Get (0)));

NetDeviceContainer bridgeDevices2 = bridge.Install (lanNodes.Get (1), NetDeviceContainer (p2pDevices2.Get (1), csmaDevices2.Get (0)));

// Install internet stack

InternetStackHelper stack;

stack.Install (lanNodes);

stack.Install (routerNode);

// Assign IP addresses

Ipv4AddressHelper address;

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

Ipv4InterfaceContainer interfaces1 = address.Assign (NetDeviceContainer (p2pDevices1.Get (0), bridgeDevices1.Get (0)));

address.SetBase (“10.1.2.0”, “255.255.255.0”);

Ipv4InterfaceContainer interfaces2 = address.Assign (NetDeviceContainer (p2pDevices2.Get (0), bridgeDevices2.Get (0)));

address.SetBase (“10.1.3.0”, “255.255.255.0”);

Ipv4InterfaceContainer interfaces3 = address.Assign (csmaDevices1);

address.SetBase (“10.1.4.0”, “255.255.255.0”);

Ipv4InterfaceContainer interfaces4 = address.Assign (csmaDevices2);

// Create UDP server on one of the LAN nodes

UdpServerHelper server (9);

ApplicationContainer serverApp = server.Install (lanNodes.Get (5));

serverApp.Start (Seconds (1.0));

serverApp.Stop (Seconds (10.0));

// Create UDP client on one of the LAN nodes

UdpClientHelper client (interfaces4.GetAddress (1), 9);

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

client.SetAttribute (“Interval”, TimeValue (MilliSeconds (10)));

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

ApplicationContainer clientApp = client.Install (lanNodes.Get (2));

clientApp.Start (Seconds (2.0));

clientApp.Stop (Seconds (10.0));

FlowMonitorHelper flowHelper;

Ptr<FlowMonitor> flowMonitor = flowHelper.InstallAll ();

Simulator::Stop (Seconds (11.0));

Simulator::Run ();

CalculateBridgingPerformance (flowMonitor, flowHelper);

Simulator::Destroy ();

return 0;

}

Explanation

1. Setup: The code sets up a simple network topology with a router and two LAN segments, each connected via point-to-point links to the router.
2. Bridge Configuration: Bridges are created using the BridgeHelper to connect the LAN segments.
3. Applications: A UDP server is installed on one of the LAN nodes, and a UDP client is installed on another LAN node to generate traffic across the bridge.
4. Flow Monitor: The FlowMonitor is used to gather performance metrics like throughput, latency, and packet loss.
5. CalculateBridgingPerformance Function: This function calculates the total throughput, average latency, and packet loss, and logs these metrics to evaluate the performance of the network bridges.

Running the Simulation

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

./waf configure

./waf build

./waf –run your-script-name

Replace your-script-name with the actual name of your script file.

Here, we explore how the Network bridges can estimate and simulated in ns3 to calculate the network communication. Further details were provided about how the network bridge performs in other simulation tools.

Our team at ns3simulation.com specializes in calculating network bridging using ns3tool and conducting performance analysis. Share your parameters with us and receive top-notch results from our experts.