How to Start Simple Mail Transfer Protocol Projects Using NS3

To start a Simple Mail Transfer Protocol (SMTP) project in NS3 that comprises to replicate the transmitting and receiving of email messages through the network. SMTP is an application-layer protocol, which functions over TCP, and we can be replicated their behavior to utilize BulkSendApplication and PacketSink within NS3 environment, specifying the client-server email interaction.

Below is a simple strategy to get started:

Steps to Start Simple Mail Transfer Protocol Projects in NS3

  1. Understand SMTP and Its Simulation Requirements
  • What is SMTP?
    • Protocol for transmitting emails among the mail servers and from clients to mail servers.
    • It functions through TCP that normally on port 25 (unencrypted), port 587 (SMTP with STARTTLS), or port 465 (SMTPS).
  • Key Aspects to Simulate:
    • SMTP client-server interaction.
    • Message delivery over TCP.
    • Computation of performance metrics such as throughput and delay.
  1. Set Up NS3
  • Install NS3:
    • Go to nsnam.org to download and install NS3 environment.
  • Verify Installation:

./waf –run scratch/test-example

  • Required Modules:
    • internet: It supports for IP and TCP functionalities.
    • applications: For replicating application-layer traffic.
    • point-to-point or wifi: For network topology, this module utilize.
  1. Plan the SMTP Simulation
  • Topology:
    • A simple client-server configuration: Node A (SMTP client) ↔ Node B (SMTP server).
    • Optional: Prolong to replicate several clients and servers.
  • Goals:
    • To mimic from the client to the server transmitting an email.
    • Estimate the metrics like email delivery time, throughput, and network overhead.
  1. Write a Basic SMTP Simulation
  • Replicate the email transfer and PacketSink as the SMTP server using BulkSendApplication.
  • Example: Simple SMTP Communication

#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 nodes;

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

// Create point-to-point link

PointToPointHelper p2p;

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

p2p.SetChannelAttribute(“Delay”, StringValue(“5ms”));

NetDeviceContainer devices = p2p.Install(nodes);

// Install Internet stack

InternetStackHelper stack;

stack.Install(nodes);

// Assign IP addresses

Ipv4AddressHelper ipv4;

ipv4.SetBase(“10.1.1.0”, “255.255.255.0”);

Ipv4InterfaceContainer interfaces = ipv4.Assign(devices);

// Set up SMTP client (BulkSendApplication)

uint16_t port = 25; // SMTP default port

Address serverAddress(InetSocketAddress(interfaces.GetAddress(1), port));

BulkSendHelper smtpClient(“ns3::TcpSocketFactory”, serverAddress);

smtpClient.SetAttribute(“MaxBytes”, UintegerValue(1024 * 1024)); // Simulating a 1 MB email

ApplicationContainer clientApp = smtpClient.Install(nodes.Get(0));

clientApp.Start(Seconds(1.0));

clientApp.Stop(Seconds(5.0));

// Set up SMTP server (PacketSink)

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

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

serverApp.Start(Seconds(0.5));

serverApp.Stop(Seconds(5.0));

// Enable PCAP tracing

p2p.EnablePcapAll(“smtp-simulation”);

// Run the simulation

Simulator::Run();

Simulator::Destroy();

return 0;

}

  1. Extend the Simulation
  • Multiple Emails:
    • Replicate numerous email transmissions to utilize several examples of the BulkSendApplication.
  • Simulate Large Email Sizes:
    • Modify the MaxBytes attribute denoting the larger files or attachments.

smtpClient.SetAttribute(“MaxBytes”, UintegerValue(10 * 1024 * 1024)); // 10 MB email

  • Add Multiple Clients and Servers:
    • We make more nodes to replicate a network including numerous clients and servers.
  1. Simulate SMTP-Specific Behavior
  • Custom Packet Headers:
    • We can prolong Packet class of NS3 containing the fields such as sender, recipient, and subject.
  • Error Handling:
    • We can stop packets or launch delays, replicating the retransmissions.
  1. Test and Debug
  • Enable Logging:

export NS_LOG=BulkSendApplication=level_all

./waf –run scratch/smtp-simulation

  • Inspect Packet Flow:
    • Examine email traffic within Wireshark to utilize PCAP tracing.

p2p.EnablePcapAll(“smtp”);

  • Verify Data Delivery:
    • Record the total bytes that are obtained at the server:

Ptr<PacketSink> sink = DynamicCast<PacketSink>(serverApp.Get(0));

std::cout << “Total Bytes Received: ” << sink->GetTotalRx() << std::endl;

  1. Evaluate SMTP Performance
  • Metrics to Measure:
    • Throughput: We want to calculate the bytes that are transmitted for each second.
    • Latency: Determine the duration for email delivery.
    • Packet Loss: We assess the volume of retransmitted packets.
  • Use FlowMonitor:

FlowMonitorHelper flowMonitor;

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

monitor->SerializeToXmlFile(“smtp-performance.xml”, true, true);

  1. Advanced Features
  • Secure SMTP (SMTPS):
    • Replicate the encrypted interaction by inserting computational delays or additional overhead to packets.
  • Dynamic Topology:
    • We launch mobility to replicate the dynamic client-server connections.
  • Traffic Prioritization:
    • Give precedence to email traffic over other applications to utilize TrafficControlHelper.
  • TCP Variants:
    • Test with various TCP flavors such as TCP Reno or Cubic.

Config::SetDefault(“ns3::TcpL4Protocol::SocketType”, StringValue(“ns3::TcpReno”));

Within this module, we exhibited the entire simulation method with example coding for Simple Mail Transfer Protocol Projects, simulated and evaluated using NS3 tool. Extra in-depth details will also offer in another manual.

Reach out to us to ensure your project is completed on schedule. At phdprojects.org, we’re here to help you kick off your Simple Mail Transfer Protocol projects using the NS3 tool with a quick response and top-notch support. Let our experts handle your project performance, as our developers specialize in BulkSendApplication and PacketSink, providing you with clear and comprehensive explanations.