oao519p / nctulab2

Network Topology with Mininet

This repository is lab for NCTU course "Introduction to Computer Networks 2018".

---

Abstract

In this lab, we are going to write a Python program which can generate a network topology using Mininet and use iPerf to measure the bandwidth of the topology.

---

Objectives

1. Learn how to create a network topology with Mininet
2. Learn how to measure the bandwidth in your network topology with iPerf

---

Execution

TODO:

• Describe how to execute your program
• Show the screenshot of using iPerf command in Mininet

1. First run the topology.py by " [sudo] chmod +x topology.py "
2. then can run by " [sudo] ./topology.py "
3. after running , it will enter to Mininet's CLI mode
4. use iPerf command to measure the topology

screenshot for using iPerf command in Mininet

---

Description

Mininet API in Python

TODO:

• Describe the meaning of Mininet API in Python you used in detail

• Mininet(topo= , link= , controller= ): Create Mininet object

• addSwitch(): Add switch to topo

• addHost(): Add host to topo

• addLink(node1 , node2, bw= , delay= , loss= ): node2 link with node1 (bidirectional)

---

• setLogLevel(): Setup loglevel (Convenience function to support lowercase names) 參數: 'info' / 'debug' / 'output'

• dumpNodeConnections(): dump connections to/from a set of nodes

• pingAll(): Ping between all hosts >> 檢測網路互通性

---

• start(): Start controller and switches
• stop(): Stop the controller(s), switches and hosts
• CLI(Mininet object): Start and run interactive or batch mode CLI

---

• TClink & OvScontroller for creating Mininet object's parameter

iPerf Commands

TODO:

• Describe the meaning of iPerf command you used in detail

• iPerf is a tool for measuring bandwidth on IP networks

for topo2.png , should use "h6 iperf -s -u -i 1 > ./out/result & " and "h3 iperf -c 10.0.0.6 -u -i 1"

• -s: start up with server mode
• -u: using UDP portocol
• -i 1: interval time with 1 sec
• -c 10.0.0.6: host start up with client mode (10.0.0.6 is server's address)

Tasks

TODO:

• Describe how you finish this work step-by-step in detail

1. Environment Setup

• clone initial repository from github and login to container by SSH
• run Mininet with OvS's controller ( to support topos )

if not using OvS, it will get error . By solving this error, use " service openvswitch-switch start ".

2. Example of Mininet

• change directory
• change the .py into executable mode by " chmod +x example.py "

since the data in Mininet have no permission initial. +x : execute

• then see the result of creation & connection of 2 hosts and 1 switch.

3. Topology Generator

• view topo2.png
• generate topology.py by " touch topology.py " under /src/.
• refer to example.py, finish topology.py
• code part:

1. create switches(numbers = 5) and hosts( = 10)
2. construct each links (total 14 links) and set up bandwideth, delay, loss rate
3. define simpleTest() and add two requirement in here (i) Dump every connections information (ii) Enter CLI mode instead of end the network immediatly

4. Measurement

• change topology.py executable as task 2 done with example.py
• execute topology.py
• after running , it will autoly enter into Mininet CLI mode
• use iPerf command to test topology.py by " h6 iperf -s -u -i 1 > ./out/result & " and " h3 iperf -c 10.0.0.6 -u -i 1 "
• it is success if loss rate is in range 13%~18%.

---

References

TODO:

• Please add your references in the following

• Mininet
  • Mininet Walkthrough
  • Introduction to Mininet
  • Mininet Python API Reference Manual
  • A Beginner's Guide to Mininet
  • GitHub/OSE-Lab - 熟悉如何使用 Mininet
  • 菸酒生的記事本 – Mininet 筆記
  • Hwchiu Learning Note – 手把手打造仿 mininet 網路
  • 阿寬的實驗室 – Mininet 指令介紹
  • Mininet 學習指南
  • MININET部分指令以及其用法总结
• Python
  • Python 2.7.15 Standard Library
  • Python Tutorial - Tutorialspoint
• Others
  • iPerf3 User Documentation
  • Cheat Sheet of Markdown Syntax
  • Vim Tutorial – Tutorialspoint
  • 鳥哥的 Linux 私房菜 – 第九章、vim 程式編輯器

---

Contributors

TODO:

• Please replace "YOUR_NAME" and "YOUR_GITHUB_LINK" into yours

• 吳宜珈
• David Lu

---

License

GNU GENERAL PUBLIC LICENSE Version 3