An introduction to fundamental concepts of computer networks and widely used networking technologies. Topics include application protocol design; principles of congestion and error control protocols; network routing; local, wireless, and access networks; network security; and networking programming. The Internet suite of protocols will be discussed in depth. Students will learn about conventional and state-of-the-art computer networks through problem sets and programming projects. More...

Credits 4
Section A
Semester Fall 2019
Date Time, Location TR 9:30 - 10:45 am,
Davis 117
Instructor Ying Li
Office: Davis 111
Phone: (207)-859-5852
Office hours: MTWR 2:00 - 4:00 pm or by appointment
If the door is open and I'm not already in a meeting, feel free to come in.
  • CS 231 - Data Structures and Algorithms
  • CS 232 - Computer Organization
  • Or permission of the instructor
Course Goals
  1. Students demonstrate an understanding of the fundamental concepts of computer networks and widely-used networking technologies.
  2. Students demonstrate an understanding of the Internet suite of protocols.
  3. Students demonstrate an ability to utilize the commonly used networking tools.
  4. Students demonstrate an ability to analyze the network performance.
  5. Students present methods, algorithms, results, and designs in an organized and competently written manner.
Assignments Bi-weekly Projects: Every project has two parts (the problem set and the programming assignment) and is assigned usually every other Tuesday. The usual deadline is the midnight of the second Tuesday after the project is assigned.
Submission, Late Policy

You are expected to email me your projects. The subject of your email should follow this format CS331 Fall2019 Proj# -- Your Name (e.g., CS331 Fall2019 Proj1 -- Ying Li). The email should have three attachments, your solutions to the problem, one archive for your source codes, and one PDF for your write-up. All your source codes should be compressed into an archive, and your solutions to the problem set should be converted into a single PDF file. Please follow the instructions to submit your projects.

Projects are graded based on a 30 point scale. Late projects will receive a maximum score of 26/30, so handing in something on the due date is generally better than handing in a complete assignment late. As you all have busy schedules, you may have one four-day extensions you can use at your discretion over the course of the semester, excepting only the final project. That means you may choose to hand in one of the projects except the last one on Saturday instead of Tuesday.

  • Two midterms: There will be two midterms on Thursday, October 10, and Thursday, November 14.
  • Final Exam: It will be on Wednesday, December 11.
Class Participation You are expected to attend every class. Discussion is a vital part of the learning experience. Good class discussion needs your contribution.
Grading The course grade will be determined as follows:
  • Projects: 55%
  • Two midterms: 20%
  • Final Exam: 20%
  • Class Participation: 5%
Text James F. Kurose and Keith W. Ross: Computer Networking: A Top-Down Approach, Seventh Edition, Pearson, 2016, ISBN 978-0-13-359414-0.
Collaboration, Academic honesty

Computer science, both academically and professionally, is a collaborative discipline. In any collaboration, however, all parties are expected to make their own contributions and to generously credit the contributions of others. In our class, therefore, collaboration on homework and programming assignments is encouraged, but you as an individual are responsible for understanding all the material in the assignment and doing your own work. Always strive to do your best, give generous credit to others, start early, and seek help early from both your professors and classmates.

The following rules are intended to help you get the most out of your education and to clarify the line between honest and dishonest work. We reserve the right to ask you to verbally explain the reasoning behind any answer or code that you turn in and to modify your project grade based on your answers. It is vitally important that you turn in work that is your own. We do use automated plagiarism detection software, so please be sure to abide by these, rather minimal, rules. Reports of academic dishonesty are handled by an academic review board and a finding of academic dishonesty may result in significant sanctions. For more details on Colby's Academic Integrity policies and procedures, see

  • If you have had a substantive discussion of any homework or programming solution with a classmate, then be sure to cite them in your write-up. If you are unsure of what constitutes "substantive", then ask me or err on the side of caution. As one rule of thumb, if you see more than 10 lines of someone else's code, then you should cite them. You will not be penalized for working together.
  • You must not copy answers or code from another student either by hand or electronically. Another way to think about it is that you should be talking English with one another, not program languages.
The Colby Affirmation

Colby College is a community dedicated to learning and committed to the growth and well-being of all its members.

As a community devoted to intellectual growth, we value academic integrity. We agree to take ownership of our academic work, to submit only work that is our own, to fully acknowledge the research and ideas of others in our work, and to abide by the instructions and regulations governing academic work established by the faculty.

As a community built on respect for ourselves, each other, and our physical environment, we recognize the diversity of people who have gathered here and that genuine inclusivity requires active, honest, and compassionate engagement with one another. We agree to respect each other, to honor community expectations, and to comply with College policies.

As a member of this community, I pledge to hold myself and others accountable to these values. More ...

Title IX Statement

Colby College prohibits and will not tolerate sexual misconduct or gender-based discrimination of any kind. Colby is legally obligated to investigate sexual misconduct (including, but not limited to sexual assault and sexual harassment).

If you wish to speak confidentially about an incident of sexual misconduct, please contact Colby Counseling Services (207-859-4490) or the Director of the Gender and Sexual Diversity Program, Emily Schusterbauer (207-859-4093).

Students should be aware that faculty members are considered responsible employees; as such, if you disclose an incident of sexual misconduct to a faculty member, they have an obligation to report it to Colby's Title IX Coordinator. "Disclosure" may include communication in-person, via email/phone/text, or through class assignments.

To learn more about sexual misconduct or report an incident, visit

© 2019 Ying Li. Page last modified: 08/20/2019