🌐 D0002E Computer Networking — Lab Simulations

Luleå University of Technology

This repository contains ns-3 simulation scripts and lab questions for 6 labs covering Chapters 2–6 and 8 of Kurose & Ross, Computer Networking: A Top-Down Approach (8th edition). Each lab generates PCAP files that you analyze in Wireshark to answer questions about network protocol behavior.

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📋 Prerequisites

To complete these labs, you will need:

• 📖 Textbook: Kurose & Ross, Computer Networking: A Top-Down Approach, 8th edition. (Chapter numbers may vary between editions)
• 🦈 Wireshark: Free packet analyzer. Download here.
• 🛠️ ns-3.46: Network simulator. (Setup instructions below)

Tip

Windows users: If you are on Windows, we heavily recommend using WSL with Ubuntu and running ns-3 inside WSL.

📚 Windows WSL Setup Guide

This is the recommended setup because these labs are Linux-based, but the generated .pcap files still open perfectly in your native Windows Wireshark.

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🚀 ns-3 Setup Guide

1. System Requirements

🐧 Linux is required. Ubuntu 22.04 or 24.04 are recommended and known to work flawlessly.

2. Install Dependencies

Open your terminal and install the required tools:

sudo apt update
sudo apt install g++ python3 cmake ninja-build git wget

3. Download and Build ns-3

Download and extract the ns-3.46.1 source, then build the simulator:

# Download and extract ns-allinone-3.46.1
wget https://www.nsnam.org/releases/ns-allinone-3.46.1.tar.bz2
tar xvf ns-allinone-3.46.1.tar.bz2
cd ns-allinone-3.46.1/ns-3.46.1

# Configure and build
./ns3 configure --enable-examples
./ns3 build

4. Place the Lab Files

Clone this repository directly into the scratch/d0002e/ directory inside your ns-3 tree.

# From the ns-3 root (ns-allinone-3.46.1/ns-3.46.1/):
git clone https://github.com/eislab-cps/D0002E.git scratch/d0002e

After cloning, your structure should look like this:

ns-3.46.1/scratch/d0002e/
├── CMakeLists.txt
├── lab1-http-dns/
├── lab2-tcp-udp/
├── lab3-ip-dataplane/
├── lab4-ip-controlplane/
├── lab5-link-layer/
└── lab6-tls/

Then rebuild ns-3 so it registers the new examples:

./ns3 configure --enable-examples
./ns3 build

5. Verify the Installation

Run a default ns-3 example to ensure everything works:

./ns3 run first

Then try running the first lab simulation:

./ns3 run "scratch/d0002e/lab1-with-guidance --scenario=basic"

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🎓 Student Notes & Best Practices

• 💻 Run ns-3 strictly from Linux or WSL, not native Windows.
• 📁 WSL Users: Keep the project under your Linux home directory (/home/<user>/...), not under the mounted Windows drive (/mnt/c/...).
• 🛑 Generated output folders and PCAP files are local artifacts. Do not commit them back to the repository.
• 🎲 The lab scripts use reproducible seeds and write captures under seed-specific output folders (e.g., scratch/d0002e/lab 2 output/seed42/).
• 🎥 Labs 2, 3, 5, and 6 write netanim.xml files alongside the PCAP captures. This requires an ns-3 build with the netanim module enabled.
• 🔒 Lab 6 Note: Uses the executable name lab6-with-guidance, but its TLS capture output is written under scratch/d0002e/lab 7 output/.

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📂 Repository Structure

README.md                              ← This file
WSL_SETUP.md                           ← Windows + WSL setup guide
CMakeLists.txt                         ← ns-3 build configuration for all labs
.gitignore
lab1-http-dns/
  README.md                            ← Lab 1 instructions and questions
  lab1-with-guidance.cc                ← Lab 1 simulation source
lab2-tcp-udp/
  README.md                            ← Lab 2 instructions and questions
  lab2-with-guidance.cc                ← Lab 2 simulation source
lab3-ip-dataplane/
  README.md                            ← Lab 3 instructions and questions
  lab3-with-guidance.cc                ← Lab 3 simulation source
lab4-ip-controlplane/
  README.md                            ← Lab 4 instructions and questions
  lab4-with-guidance.cc                ← Lab 4 simulation source
lab5-link-layer/
  README.md                            ← Lab 5 instructions and questions
  lab5-with-guidance.cc                ← Lab 5 simulation source
lab6-tls/
  README.md                            ← Lab 6 instructions and questions
  lab6-with-guidance.cc                ← Lab 6 simulation source

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🔬 Lab Curriculum Overview

Lab	Topic	Chapter	Questions
1	🌐 HTTP and DNS	2	25
2	🔄 TCP and UDP	3	19
3	🔀 IP Data Plane	4	10
4	🗺️ IP Control Plane	5	12
5	🔗 Link Layer and LANs	6	16
6	🔒 Transport Layer Security	8	13
	Total		95

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🏷️ Question Tag Legend

Each question in the labs is tagged to indicate how you should approach answering it:

Tag	Methodology
[W]	🦈 Answer using Wireshark capture analysis
[C]	💻 Answer by reading the simulation source code (labN-with-guidance.cc)
[B]	🦈+💻 Answer using both Wireshark and source code
[T]	📖 Answer from textbook theory
[V]	✅ Verify Wireshark observations against textbook explanations
[_+X]	🧪 Experiment! In addition to what is instructed at "_", experiment with different input parameters

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🏃‍♀️ How to Work Through a Lab

1. 📖 Read the lab README.md in the corresponding directory.
2. 🔍 Examine the .cc source file — the top comments describe the network topology, available scenarios, and expected output.
3. 🏗️ Build and run the simulation using the commands provided in the lab README.
4. 🦈 Open the generated .pcap files in Wireshark.
5. ✍️ Answer the questions applying the technique indicated by each question's tag.