Engineering Clinic

Simulation and Analysis of DNS Query-Response Mechanism over UDP in NS-3 Aim: To design and simulate a DNS query-response mechanism over UDP sockets using NS3. The client sends QUERY:<domain> packets to a DNS server through a router; the server replies with ANSWER:<domain>:<ip> or NXDOMAIN . The experiment measures throughput, delay, and packet delivery ratio, and visualises packet flow using NetAnim and Gnuplot. Prompt: "Implement a simple DNS query-response application over UDP sockets in NS3. The simulation should include a DNS Client node, a Router, and a DNS Server node connected via point-to-point links. The client should send DNS queries ( QUERY:<domain> ) and the server should respond with IP addresses ( ANSWER:<domain>:<ip> ) or NXDOMAIN . Include NetAnim animation output, FlowMonitor statistics, and Gnuplot graph generation for throughput and delay." LLM used: Claude (Anthropic), Gemini Source Code: #include ...

Performance Analysis of TCP Reno Congestion Control Under Varying Round-Trip Time Conditions: An ns-3 Simulation Study PROMPT Part 1: You are an expert in ns-3 network simulation and C++. I want you to design and implement a complete ns-3 simulation in C++ to analyze the performance of TCP Reno over a point-to-point link with varying RTT values (10 ms to 200 ms). Requirements: Simulation Setup Create a point-to-point network topology (2 nodes). Configure link parameters such as: Data rate (choose a reasonable default like 5 Mbps or 10 Mbps) Packet size Queue type (DropTail or similar) Use TCP Reno as the transport protocol. Ensure RTT variation is achieved by modifying propagation delay (range: 10 ms to 200 ms in steps). Traffic Configuration Use a TCP application (e.g., BulkSendApplication or OnOffApplication). Configure a receiver using Pa...

Simulation of Selective Repeat ARQ and Go-Back-N under High Error Rates using ns-3 | NS3 Project 13 To simulate Selective Repeat (SR) and Go-Back-N (GBN) ARQ protocols using ns-3 and compare their performance under high error rates in terms of throughput, delay, and packet loss. LLM + PROMPT (VERY IMPORTANT) LLM Used: ChatGPT (OpenAI GPT-5.3) Prompt Used: “Simulate Selective Repeat ARQ and compare its performance with Go-Back-N under high error rates using ns-3. Provide complete code, steps, and graph generation.” NETWORK TOPOLOGY Two nodes: Node 0 → Sender Node 1 → Receiver Connected using Point-to-Point link Parameters: Bandwidth: 5 Mbps Delay: 2 ms Error Rate: High (e.g., 1e-3) PROTOCOL MAPPING GBN → TCP Tahoe SR → TCP NewReno Source Code: #include "ns3/core-module.h" #include "ns3/network-module.h" #include "ns3/internet-module.h" #include "ns3/point-to-point-m...