CS422: Computer Networks (Fall 2019)

CS422 is the undergraduate course in Computer Networks at the Dept. of Computer Science at Purdue University. In this course, we will learn how to build Internet and go through main network protocols used by one of the largest and critical cyber infrastcture (Internet), which is used by almost everyone everyday.

Instructor: Chunyi Peng
Email: chunyi AT purdue.edu
Class hours/locations: Felix Haas Hall G066, MWF 10:30AM - 11:20AM
Office hours: LWSN 2142E, M 12:00 - 13:00PM, W 13:00-14:00PM, or by appointment (send e-mail)

Teaching Assistants and PSOs

Habiba Farrukh (Email: hfarrukh@purdue.edu)

Lucas Tao (Email: tao63@purdue.edu)

Kai Ling (Email: ling59@@purdue.edu)

Your specific PSO will be given on your schedule but you are welcome to come to any PSO. NO PSOs in the first week.

Course Homepage

This webpage is our official course homepage but serves as the anchor only (no real course materials covered here). Piazza is our real course homepage. Except grades and lab submissions, all the course materials including lectures, assignments, online Q&A, announcement will be available at Piazza . Please enroll yourself if you haven't.

Contact us

You are always welcome to contact us (instructor and TAs) directly via the above email addresses, but you are recommended to contact us in the following order:


Computer Networking: A Top-Down Approach, 7th Edition, J. F. Kurose and K. W. Ross

Other useful books: Computer Networks And Internets, 6th Edition, D. E. Comer Computer Networks: A Systems Approach, 5th Edition, L. Peterson and B. Davie

Topics (tentative):

Grading Policy (tentative)

Midterms and final exam: closed book, closed notes, and no electronic devices.

Course Policy

You need to obey course polices for all the undergrad courses in the department of Computer Science, Purdue. Here, I higlhight some important ones.


No makeup exams will be given except for a documented severe medical or family emergency. It is the responsibility of the students to arrive on time for the exam. Exams are closed-book, closed-notes, closed-discussion, closed-smartphone/laptop, closed-calculator.

Due Dates

All assignments are due on the dates and times specified. It is the responsibility of the students to manage their time so that the assignments can be submitted before the deadline. NO late submissions will be accepted.

Assignment Regrades

If you feel that you have been unfairly graded on a lab assignment, homework or exam, you should petition the appropriate TA or Professor in writing within two weeks of distribution of the graded work. After two weeks, NO regrade requests will be honored. For lab assignments, you are allowed to change a few lines of code if that makes your program work, but there will be a penalty per change.

Academic Dishonesty

We wish to foster an open and collegial class environment. At the same time, we are vigorously opposed to academic dishonesty because it seriously detracts from the education of honest students. Because of this, we have the following standard policy on academic honesty, consistent with Purdue University's official policy and Purdue's Honor Pledge.

It is permissible to discuss a GENERAL METHOD of solution with other students, or to make use of high-level reference materials in the library or online. If you do this, you will be expected to CLEARLY DISCLOSE with whom you discussed the method of solution, or to cite the references used. Failure to do so will be considered cheating or plagiarism. The use of “method of solution” means a GENERAL discussion of technique or algorithm, such as one would reasonably expect to occur standing in front of a whiteboard, and precludes the detailed discussion of code or written assignments.

Specifically, looking at another student's code on his/her computer monitor or copying code from an online source is NOT allowed.

Unless otherwise explicitly specified, all written assignments or code that is submitted is to be ENTIRELY the student's own work. Using any code or copying any assignment from others or from an online source is strictly prohibited without advance prior permission from the instructor. This includes but not limited to the use of code others have submitted in the past, or solutions found on the Internet.

All students work is their own. Students who do share their work with others are as responsible for academic dishonesty as the student receiving the material. Students are not to show work to other students, in the class or outside. Students are responsible for the security of their work and should ensure that printed copies are not left in accessible places, and that filedirectory permissions are set to be unreadable/ to others (e.g. use “chmod -R 700 *” from your home directory. If you need assistance protecting your work, please contact your TAs.

Students who encourage others to cheat or plagiarize, or students who are aware of plagiarism or cheating and do not report it are also participating in academically dishonest behavior.

Be aware that we will use a software tool called MOSS(http:theory.stanford.edu aikenmoss/) to check for copying among submitted assignments. Additionally, the instructor and TA will be inspecting all submitted material to ensure honesty.

Any case of academic dishonesty will be dealt with by a severe grade penalty in the overall class grade and referral to the office of the Dean of Students.

Classroom Policy

Class participation and discussions are strongly encouraged. However, please be considerate to others: avoid coming to class late, leaving early, talking to other students, etc. Please turn off your cell phone before the class starts.

Emergency Policy

In the event of a major campus emergency, course requirements, deadlines and grading percentages are subject to changes that may be necessitated by a revised semester calendar or other circumstances. Any changes will be posted to the course web page or on Piazza Information about emergency preparedness can be found <a href=“http:www.purdue.eduehpsemergency_preparedness”>here<a>.

If you unfortunately experience a medical or any other form of emergency, please do contact your instructor as soon as possible (usually no later than 2 days within its occurance).


You can also review the policies page maintained by Professor Gene Spafford for additional information about academic honesty and other policies.


If you are experiencing stress or personal problems, Purdue provides counseling services through the Purdue CAPS Center. Please see CAPS for more details.