How to Simulate TCP IP Projects Using NS3

To simulate TCP/IP projects using NS3 has includes generating network topologies in which nodes interact using the TCP/IP protocol stack. NS3 delivers the built-in support for numerous TCP variants that contain TCP NewReno, TCP Cubic, and others; along with full IPv4/IPv6 protocol stacks.

Here’s a step-by-step implementation on how to simulate basic and advanced TCP/IP scenarios in NS3.

Steps to Simulate TCP/IP in NS3

1. Set Up NS3 Environment

Make sure that NS3 is installed on the system.

./waf configure

./waf build

2. Define the Network Topology

Initiate by describing a simple network topology using NodeContainer. In this instance, we will generate two nodes associated through a point-to-point link to emulate a simple TCP/IP communication.

NodeContainer nodes;

nodes.Create(2);  // Create 2 nodes (client and server)

3. Set up Network Configuration

To replicate TCP/IP traffic, that requires introducing a network connection among the two nodes. Utilize PointToPointHelper to generate a point-to-point link that mimics the physical connection.

PointToPointHelper pointToPoint;

pointToPoint.SetDeviceAttribute(“DataRate”, StringValue(“5Mbps”));

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

NetDeviceContainer devices;

devices = pointToPoint.Install(nodes);

4. Install Internet Stack

The Internet stack (TCP/IP) requires to be installed on both nodes. Utilize InternetStackHelper to do this:

InternetStackHelper internet;

internet.Install(nodes);

5. Assign IP Addresses

Allocate IP addresses to the nodes’ network interfaces using Ipv4AddressHelper.

Ipv4AddressHelper address;

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

Ipv4InterfaceContainer interfaces = address.Assign(devices);

6. Simulate TCP Traffic

To mimic TCP communication, we can utilize the BulkSendApplication to create TCP traffic from one node to another and the PacketSinkApplication to receive the traffic.

TCP Server (PacketSink) Setup

On the receiving node (server), install a PacketSink application to listen on a certain TCP port.

uint16_t port = 8080;  // TCP port

PacketSinkHelper sink(“ns3::TcpSocketFactory”, InetSocketAddress(Ipv4Address::GetAny(), port));

ApplicationContainer sinkApp = sink.Install(nodes.Get(1));  // Server is node 1

sinkApp.Start(Seconds(0.0));

sinkApp.Stop(Seconds(10.0));

TCP Client (BulkSend) Setup

On the sending node (client), utilize the BulkSendApplication to transfer TCP packets to the server:

BulkSendHelper source(“ns3::TcpSocketFactory”,InetSocketAddress(interfaces.GetAddress(1), port));

source.SetAttribute(“MaxBytes”, UintegerValue(0));  // Send unlimited data

ApplicationContainer sourceApp = source.Install(nodes.Get(0));  // Client is node 0

sourceApp.Start(Seconds(1.0));

sourceApp.Stop(Seconds(10.0));

7. Simulate Different TCP Variants

NS3 supports multiple TCP variants that contain TCP NewReno, TCP Tahoe, TCP Cubic, and more. We can specify the TCP variant by configuring the proper attributes.

To use TCP Cubic:

TypeId tcpTypeId = TypeId::LookupByName(“ns3::TcpCubic”);

Config::Set(“/NodeList/*/$ns3::TcpL4Protocol/SocketType”, TypeIdValue(tcpTypeId));

To use TCP NewReno:

TypeId tcpTypeId = TypeId::LookupByName(“ns3::TcpNewReno”);

Config::Set(“/NodeList/*/$ns3::TcpL4Protocol/SocketType”, TypeIdValue(tcpTypeId));

8. Enable FlowMonitor to Track Performance Metrics

To evaluate the performance of TCP connections like throughput, delay, and packet loss, utilize FlowMonitor:

FlowMonitorHelper flowmon;

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

Simulator::Run();

monitor->CheckForLostPackets();

monitor->SerializeToXmlFile(“tcp-simulation.xml”, true, true);

9. Run the Simulation

Execute the simulation for the certain time:

Simulator::Stop(Seconds(10.0));

Simulator::Run();

Simulator::Destroy();

Example Code Structure

Here’s a complete example of an NS3 simulation for a simple TCP/IP project:

#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/flow-monitor-module.h”

using namespace ns3;

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

{

// Create 2 nodes (client and server)

NodeContainer nodes;

nodes.Create(2);

// Set up point-to-point link

PointToPointHelper pointToPoint;

pointToPoint.SetDeviceAttribute(“DataRate”, StringValue(“5Mbps”));

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

NetDeviceContainer devices;

devices = pointToPoint.Install(nodes);

// Install internet stack

InternetStackHelper internet;

internet.Install(nodes);

// Assign IP addresses

Ipv4AddressHelper address;

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

Ipv4InterfaceContainer interfaces = address.Assign(devices);

// Set up TCP server (PacketSink) on node 1

uint16_t port = 8080;

PacketSinkHelper sink(“ns3::TcpSocketFactory”, InetSocketAddress(Ipv4Address::GetAny(), port));

ApplicationContainer sinkApp = sink.Install(nodes.Get(1));

sinkApp.Start(Seconds(0.0));

sinkApp.Stop(Seconds(10.0));

// Set up TCP client (BulkSend) on node 0

BulkSendHelper source(“ns3::TcpSocketFactory”, InetSocketAddress(interfaces.GetAddress(1), port));

source.SetAttribute(“MaxBytes”, UintegerValue(0));

ApplicationContainer sourceApp = source.Install(nodes.Get(0));

sourceApp.Start(Seconds(1.0));

sourceApp.Stop(Seconds(10.0));

// Enable FlowMonitor

FlowMonitorHelper flowmon;

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

// Run simulation

Simulator::Stop(Seconds(10.0));

Simulator::Run();

Simulator::Destroy();

// Print results

monitor->CheckForLostPackets();

monitor->SerializeToXmlFile(“tcp-simulation.xml”, true, true);

return 0;

}

Further Extensions

We can expand this simple TCP/IP simulation in numerous ways:

1. Multiple Clients/Servers: Add more nodes and mimic more complex traffic scenarios with multiple clients and servers.
2. TCP Congestion Control Algorithms: validate and relate diverse TCP variants (such as NewReno, Cubic, BBR) by altering the TCP socket type.
3. Network Conditions: Replicate packet loss, congestion, or delays by using error models and traffic shaping like RateErrorModel.
4. IPv6 Simulation: Adjust the Ipv4AddressHelper to utilize Ipv6AddressHelper and replicate TCP traffic over IPv6.
5. Wireless Networks: Utilize Wi-Fi or LTE modules to replicate TCP over wireless links rather than point-to-point.

Through this manual, you can explore TCP/IP projects which will be simulated and evaluated in the ns3 environment. If needed, we will deliver the detailed structured entire execution process in another script. Our team is diving into a bunch of TCP variants for your projects, so you can count on us for some great ideas. If you’re looking to simulate TCP/IP projects using the NS3 tool, check out phdprime.com. We’ll hook you up with top-notch simulation results!