How to Begin Implement Network Auditing in NS3

To begin implementing and analysing Network auditing using NS3 which needs to observe, log, and examine the network activity, making sure that compliance including predefined rules, identify anomalies, and estimate the performance. Below is a structured guidance to get started with executing network auditing in ns3:

Steps to Begin Implement Network Auditing in NS3

  1. Understand Network Auditing
  • Purpose: Network auditing concentrates on seizure and examine the data relevant to network behavior and events.
  • Goals:
    • Make sure compliance with security strategies.
    • Identify unusual or malicious activities.
    • Note logs for troubleshooting and reporting.
  • Auditing Focus Areas:
    • Node/link performance (latency, throughput).
    • Packet-level details (size, timestamps, and drops).
    • Traffic flow (source, destination, protocols).
  1. Set Up ns3
  • We can install and set up ns3 on the system:

./waf configure –build-profile=debug –enable-examples –enable-tests

./waf build

  • Confirm set up by executing:

./waf –run hello-simulator

  1. Define Auditing Requirements
  • What to Audit?
    • Traffic models like source/destination IPs, protocols, ports.
    • Packet drops or errors.
    • Bandwidth usage.
  • Where to Log?
    • Incorporation with external tools.
    • File storage like XML, CSV.
    • Console output.
  1. Set Up a Basic Network Topology

For auditing, make a basic network topology.

Example: Basic 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[])

{

Time::SetResolution(Time::NS);

// Create nodes

NodeContainer nodes;

nodes.Create(2); // Node 0: Client, Node 1: Server

// Configure point-to-point link

PointToPointHelper p2p;

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

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

// Install devices

NetDeviceContainer devices = p2p.Install(nodes);

// Install Internet stack

InternetStackHelper stack;

stack.Install(nodes);

// Assign IP addresses

Ipv4AddressHelper address;

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

Ipv4InterfaceContainer interfaces = address.Assign(devices);

// Set up a UDP echo server on Node 1

uint16_t port = 9;

UdpEchoServerHelper echoServer(port);

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

serverApp.Start(Seconds(1.0));

serverApp.Stop(Seconds(10.0));

// Set up a UDP echo client on Node 0

UdpEchoClientHelper echoClient(interfaces.GetAddress(1), port);

echoClient.SetAttribute(“MaxPackets”, UintegerValue(5));

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));

// Run simulation

Simulator::Run();

Simulator::Destroy();

return 0;

}

  1. Implement Auditing

Integrate the hooks for observing and recording the network activity.

Option 1: Packet-Level Auditing

  • Record packets that are transmitted, inherited or lost.

void PacketSentCallback(Ptr<const Packet> packet)

{

NS_LOG_UNCOND(“Packet sent: ” << packet->GetSize() << ” bytes at ” << Simulator::Now().GetSeconds() << ” seconds”);

}

void PacketReceivedCallback(Ptr<const Packet> packet)

{

NS_LOG_UNCOND(“Packet received: ” << packet->GetSize() << ” bytes at ” << Simulator::Now().GetSeconds() << ” seconds”);

}

void PacketDropCallback(Ptr<const Packet> packet)

{

NS_LOG_UNCOND(“Packet dropped at ” << Simulator::Now().GetSeconds() << ” seconds”);

}

void InstallAuditing(Ptr<Node> node)

{

Ptr<NetDevice> device = node->GetDevice(0);

device->TraceConnectWithoutContext(“MacTx”, MakeCallback(&PacketSentCallback));

device->TraceConnectWithoutContext(“MacRx”, MakeCallback(&PacketReceivedCallback));

device->TraceConnectWithoutContext(“PhyRxDrop”, MakeCallback(&PacketDropCallback));

}

Connect auditing to the nodes:

InstallAuditing(nodes.Get(0)); // Monitor Node 0

InstallAuditing(nodes.Get(1)); // Monitor Node 1

Option 2: Flow-Level Auditing

  • For in-depth statistics we need to utilize FlowMonitor.

#include “ns3/flow-monitor-helper.h”

FlowMonitorHelper flowmonHelper;

Ptr<FlowMonitor> monitor = flowmonHelper.InstallAll();

// Serialize FlowMonitor results to an XML file

monitor->SerializeToXmlFile(“network-audit.xml”, true, true);

Analyze Flows:

monitor->CheckForLostPackets();

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

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

for (auto &flow : stats)

{

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

NS_LOG_UNCOND(“Flow ” << flow.first << ” (” << t.sourceAddress << ” -> ” << t.destinationAddress << “)”);

NS_LOG_UNCOND(”  Tx Packets: ” << flow.second.txPackets);

NS_LOG_UNCOND(”  Rx Packets: ” << flow.second.rxPackets);

NS_LOG_UNCOND(”  Throughput: ” << (flow.second.rxBytes * 8.0 / (flow.second.timeLastRxPacket.GetSeconds() – flow.second.timeFirstTxPacket.GetSeconds())) << ” bps”);

}

  1. Run and Test
  • Construct the simulation script then run it using NS3:

./waf –run scratch/network-audit

  • Confirm records or the network-audit.xml file for auditing information.
  1. Enhance Auditing Features
  • To refine the aspects of network auditing, we have to integrate:
    • Traffic analysis according to the protocols like TCP, UDP.
    • Node/link-level resource usage such as CPU, bandwidth.
    • Anomaly detection approaches.

Example: Protocol-Specific Auditing

void ProtocolAuditCallback(Ptr<const Packet> packet, Ptr<Ipv4> ipv4, uint32_t interface)

{

Ipv4Header ipv4Header;

packet->PeekHeader(ipv4Header);

if (ipv4Header.GetProtocol() == 17) // UDP

{

NS_LOG_UNCOND(“UDP Packet from ” << ipv4Header.GetSource() << ” to ” << ipv4Header.GetDestination());

}

else if (ipv4Header.GetProtocol() == 6) // TCP

{

NS_LOG_UNCOND(“TCP Packet from ” << ipv4Header.GetSource() << ” to ” << ipv4Header.GetDestination());

}

}

  1. Analyze Results
  • With the support of logs or FlowMonitor outcomes to detect:
    • Network performance parameters.
    • Anomalies like packet loss, unexpected traffic models.
  • Transfer information into external tools such as gnuplot or Python for visualization.

We demonstrated the core approach with example code for Network Auditing that were implemented and analysed using NS3 environment. More information regarding this topic will be made available.