How to Begin Implement Network Segmentation in NS3

To implement the network segmentation using NS3 which requires splitting a network into numerous smaller sub-networks (subnets), each subnets with their individual collection of addresses and perhaps unique routing rules. Network segmentation improves the performance, security, and manageability.

Below is a step-by-step instruction to get started with implementing network segmentation in ns3:

Steps to Begin Implement Network Segmentation in NS3

Understand Network Segmentation

Purpose:
- Performance: Minimize congestion by separating traffic into segments.
- Security: Limit interaction among the segments for applying security rules.
- Management: Make simpler troubleshooting and network monitoring.
Key Concepts:
- Subnets including inimitable IP address ranges.
- Routers or gateways for handling the traffic among subnets.

Set Up ns3 Environment

Make sure that we have installed ns3 on the system:

git clone https://gitlab.com/nsnam/ns-3-dev.git

cd ns-3-dev

./ns3 configure –enable-examples –enable-tests

./ns3 build

Confirm the installation with:

./ns3 run hello-simulator

Design Network Topology

Describe the segments including diverse subnets that are associated through routers or gateways.
Example topology:
- Segment 1: Nodes 1 and 2 within subnet 10.1.1.0/24.
- Segment 2: Nodes 3 and 4 in subnet 10.1.2.0/24.
- Router to link both segments.

Steps to Implement Network Segmentation

(a) Create Nodes

Make nodes for every segment and a router to associate them:

NodeContainer segment1, segment2, router;

segment1.Create(2); // Nodes in Segment 1

segment2.Create(2); // Nodes in Segment 2

router.Create(1); // Router node

(b) Install Network Devices

Associate segments to the router with the help of PointToPointHelper to install network devices:

PointToPointHelper p2p;

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

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

NetDeviceContainer devices1 = p2p.Install(NodeContainer(segment1.Get(0), router.Get(0)));

NetDeviceContainer devices2 = p2p.Install(NodeContainer(segment2.Get(0), router.Get(0)));

(c) Install Internet Stack

We can install the InternetStackHelper at all nodes:

InternetStackHelper stack;

stack.Install(segment1);

stack.Install(segment2);

stack.Install(router);

(d) Assign IP Addresses

Allocate an IP addresses to every single network segment:

Ipv4AddressHelper address1, address2;

address1.SetBase(“10.1.1.0”, “255.255.255.0”);

Ipv4InterfaceContainer interfaces1 = address1.Assign(devices1);

address2.SetBase(“10.1.2.0”, “255.255.255.0”);

Ipv4InterfaceContainer interfaces2 = address2.Assign(devices2);

(e) Set Up Routing

Allow route transmitting at the router:

Ptr<Ipv4> ipv4Router = router.Get(0)->GetObject<Ipv4>();

ipv4Router->SetAttribute(“IpForward”, BooleanValue(true));

Set up static or dynamic routes:
- Static Routing:

Ipv4StaticRoutingHelper staticRouting;

Ptr<Ipv4StaticRouting> routingSegment1 = staticRouting.GetStaticRouting(segment1.Get(0)->GetObject<Ipv4>());

routingSegment1->AddNetworkRouteTo(Ipv4Address(“10.1.2.0”), Ipv4Mask(“255.255.255.0”), Ipv4Address(“10.1.1.1”), 1);

Ptr<Ipv4StaticRouting> routingSegment2 = staticRouting.GetStaticRouting(segment2.Get(0)->GetObject<Ipv4>());

routingSegment2->AddNetworkRouteTo(Ipv4Address(“10.1.1.0”), Ipv4Mask(“255.255.255.0”), Ipv4Address(“10.1.2.1”), 1);

Install Applications

Replicate the traffic in and among the segments:
- UDP Echo Server at one segment:

UdpEchoServerHelper echoServer(9);

ApplicationContainer serverApp = echoServer.Install(segment2.Get(1));

serverApp.Start(Seconds(1.0));

serverApp.Stop(Seconds(10.0));

- UDP Echo Client functions at alternative segment:

UdpEchoClientHelper echoClient(Ipv4Address(“10.1.2.2”), 9);

echoClient.SetAttribute(“MaxPackets”, UintegerValue(10));

echoClient.SetAttribute(“Interval”, TimeValue(Seconds(1.0)));

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

ApplicationContainer clientApp = echoClient.Install(segment1.Get(0));

clientApp.Start(Seconds(2.0));

clientApp.Stop(Seconds(10.0));

Complete Example Code

Here’s a comprehensive sample outline of network segmentation:

#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[]) {

CommandLine cmd;

cmd.Parse(argc, argv);

// Create nodes

NodeContainer segment1, segment2, router;

segment1.Create(2); // Segment 1 nodes

segment2.Create(2); // Segment 2 nodes

router.Create(1); // Router node

// Create links