How to Begin Implement Network Policy Enforcement in NS3

To implement network policy enforcement in ns-3, we make a mechanism that permits or deny traffic according to their predefined policies. Network policy enforcement can be achieved through methods such as access control, congestion prioritization, and routing policies. Here’s how to get started:

Steps to Begin Implement Network Policy Enforcement in NS3

1. Understand Network Policy Enforcement

• Purpose: According to structural for behavior control network or network-level policies.
• Common Scenarios:
  • Blocking unauthorized congestion for sample by IP, port, or protocol.
  • Traffic prioritization according to their QoS (Quality of Service).
  • Routing congestion based on the predefined paths.

2. Set up ns-3

• Install ns-3:

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

./waf build

• Verify installation:

./waf –run hello-simulator

3. Define Policy Requirements

• Identify what you want to enforce:
  • Access Control: Permit or block the detailed congestion.
  • QoS Policies: Prioritize can some category of traffic.
  • Routing Policies: congestion route by detailed paths.

4. Set up a Basic Network Topology

Generate a basic network in which policies can be executed.

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(4); // Client, Router1, Router2, Server

// Configure point-to-point links

PointToPointHelper p2p;

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

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

// Connect nodes

NetDeviceContainer devices1 = p2p.Install(nodes.Get(0), nodes.Get(1)); // Client to Router1

NetDeviceContainer devices2 = p2p.Install(nodes.Get(1), nodes.Get(2)); // Router1 to Router2

NetDeviceContainer devices3 = p2p.Install(nodes.Get(2), nodes.Get(3)); // Router2 to Server

// Install Internet stack

InternetStackHelper stack;

stack.Install(nodes);

// Assign IP addresses

Ipv4AddressHelper address;

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

Ipv4InterfaceContainer interfaces1 = address.Assign(devices1);

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

Ipv4InterfaceContainer interfaces2 = address.Assign(devices2);

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

Ipv4InterfaceContainer interfaces3 = address.Assign(devices3);

// Configure routing

Ipv4GlobalRoutingHelper::PopulateRoutingTables();

// Set up a UDP echo server on the server node

uint16_t port = 9;

UdpEchoServerHelper echoServer(port);

ApplicationContainer serverApp = echoServer.Install(nodes.Get(3));

serverApp.Start(Seconds(1.0));

serverApp.Stop(Seconds(10.0));

// Set up a UDP echo client on the client node

UdpEchoClientHelper echoClient(interfaces3.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;

}

5. Add Access Control Policies

• Use packet filtering for enforce the access control.

Example: Packet Filtering

void AccessControlCallback(Ptr<Socket> socket, Ptr<Packet> packet, const Address &from)

{

Ipv4Header ipv4Header;

packet->PeekHeader(ipv4Header);

Ipv4Address source = ipv4Header.GetSource();

Ipv4Address destination = ipv4Header.GetDestination();

// Block traffic from a specific source to destination

if (source == Ipv4Address(“10.1.1.1”) && destination == Ipv4Address(“10.1.3.1”))

{

NS_LOG_UNCOND(“Access Control: Dropped packet from ” << source << ” to ” << destination);

return; // Drop packet

}

NS_LOG_UNCOND(“Access Control: Allowed packet from ” << source << ” to ” << destination);

socket->ForwardUp(packet, from);

}

void InstallAccessControl(Ptr<Node> node)

{

Ptr<Socket> socket = Socket::CreateSocket(node, TypeId::LookupByName(“ns3::UdpSocketFactory”));

socket->SetRecvCallback(MakeCallback(&AccessControlCallback));

}

Attach Access Control to a Node:

InstallAccessControl(nodes.Get(1)); // Attach to Router1

6. Add QoS Policies

• Use the Control component for congestion to prioritize the some congestion.
• Example: Established the high-priority queue for detailed congestion.

TrafficControlHelper tch;

tch.SetRootQueueDisc(“ns3::FqCoDelQueueDisc”);

QueueDiscContainer qdiscs = tch.Install(devices2); // Apply on Router1 to Router2 link

7. Add Routing Policies

• Alter the routing tables for enforce the detailed paths.
• Example: Static Routing

Ipv4StaticRoutingHelper staticRoutingHelper;

Ptr<Ipv4StaticRouting> staticRouting = staticRoutingHelper.GetStaticRouting(nodes.Get(1)->GetObject<Ipv4>());

staticRouting->AddHostRouteTo(Ipv4Address(“10.1.3.1”), Ipv4Address(“10.1.2.2”), 1); // Force route through specific link

8. Run and Test

• Create and process for the replication:

./waf –run scratch/policy-enforcement

• Observe logs or use to validate the policy enforcement FlowMonitor.

9. Enhance Policy Enforcement

• Enhance:
  • Stateful policies for sample track TCP connections.
  • Dynamic rules according to their congestion design or load.
• It replicates the further complex environment through different clients, servers, and routers.

10. Analyze Results

• Use:
  • Logs: Test for assigned the denied packets.
  • FlowMonitor: It examine for performance of metrices such as throughput, latency, and packet loss.

In this setup, we collect the innovative information regarding the Network policy enforcement and how to evaluate the network and its responds to these policies. We design to bring the additional information concerning this process in advance setup.