CSEE 4119: An Introduction to Computer Networks (Spring 2018)


The course will cover the core elements of modern Internet technology and protocols, including the application, transport, network, link layers and physical layers, for both wired and wireless networks. Coverage roughly corresponds to Chapters 1-8 of the textbook, with selected materials from the later chapters, and additional instructor-provided resources.

Computer networks and the Internet
Overview of the Internet architecture - physical and logical architecture, standards, performance concerns, cybersecurity, history, public policy
Application layer
Principles, web, email, peer-to-peer, block chain, CDNs, VoIP, socket programming
Transport layer
Services, connectionless (UDP), reliable data transfer, TCP, congestion control
Network layer
Services, routers, IPv4 and IPv6, SDNs
Link layer and LAN
Services, error detection, multiple access, switched LANs, MPLS
Wireless and mobile networks (time permitting)
CDMA, 802.11, cellular networks, mobile IP
Security in computer networks (time permitting)
Threats, confidentiality, integrity, availability, TLS


Fridays, 1:10 - 3.40 pm in 501 Northwest Corner Building

Instructional Staff

Prof. Henning Schulzrinne (office hours: Tuesdays, 1 pm or by appointment), please contact at hgs@cs.columbia.edu before office hours
Instructional assistants:
Instructional assistant office hours:
All office hours are held in the CS IA room.
Vivian Helena Shen Mondays, 4.30-6.30 pm
Ishan Manjani Thursdays, 4-6 pm
Vinay Raman Ramesh Tuesdays, 4-6pm
Guo Shi Fridays, 10am-12pm
Libo Wang Wednesdays, 12:20-2:20pm


J. Kurose and K. Ross, Computer Networking - A Top-Down Approach, 7th edition

Online version; also on reserve (TK5105.875.I57 K88 2017) in the Science & Engineering Library in NWC.

Class Mailing Lists and Other Resources

Grading and Late Policies

(Percentages may be adjusted.)

50%: Homework assignments:
There will be four written and three programming homework assignments, assigned roughly every other week, including rules for late submission.
20%: Midterm:
The midterm is one class period, closed book, calculator permitted. The midterm will cover all material discussed in the course up to the week before the exam.
30%: Final:
The final exam is scheduled at the normal final exam time for this class period. The final is closed book, calculator permitted. The final is cumulative and will cover all material discussed in the course.
No "extra credit" work

All homeworks are due by the date and time specified in the assignment (usually one or two weeks after they are issued). Homework submissions will be electronic, through CourseWorks. Complete instructions will be given with each homework.

All submissions must be in PDF format, e.g., using Word or LaTeX. Scanned handwritten assignments are strongly discouraged, and scanned solutions written in pencil are not acceptable at all. Any hand-drawn figures must be clearly legible. Camera screen shots are not permitted; please use screen capture programs such as MacOS "Grab".

You can submit your assignment multiple times, but the last submission is what counts. Each submission will be time stamped. Proper submission is your responsibility; we strongly urge you to make sure you understand the submission process and submit early. You can always submit again up until the deadline, so we strongly urge you to submit well before the deadline and then submit again if you have a more updated assignment to submit later.

You are allowed a total of 5 late days, to be used as you wish throughout the semester. That means you can be five days (24 hour periods) late for Homework 2 (for example), or one day late for each of the first five homework assignments, with no point penalty. Each late day entitles you to 24 hours beyond the submission deadline. Once you have exhausted your five late days, each day (24-hour period) or partial day late incurs a 20% penalty. There are no partial late days, either for partial submission or for partial days. Late days are counted based on the last submission. In other words, if you hand in a partial assignment before the due date and a full assignment two days after the due date, you will be assessed two late days. If you do not hand in your assignment at all, you will get zero points, but lose no late days.

Solutions will be posted approximately five days after the submission deadline. No assignments will be accepted after the solution has been posted.

No other extensions will be given, except for medical emergencies certified by University Health Services or a family emergency.

Naturally, you may hand in incomplete assignments for partial credit by the deadline.

Also see the Columbia Policies and Procedures Regarding Academic Honesty.

All students or groups whose assignments are determined to be obviously very similar will receive a zero on the respective homework assignment for the first offense, and will receive an F for the course for the second offense ("all" means both the copy-er and copy-ee). More serious cases of cheating, such as copying someone's work without their knowledge or cheating on exams, will result in the person cheating receiving an F. In addition, offenses will be reported to the Dean's office, which may result in further disciplinary action, including suspension or expulsion from the program. Penalties will be given without discussion or warning; the first notice you receive may be a letter from the Dean. Note that you are responsible for not leaving copies of your assignments lying around and for protecting your files accordingly.


We would like the course to run smoothly and we'd like you to enjoy the course. Feel free to let us know what you find good and interesting about the course. Let us know sooner about the reverse. See us during office hours, leave us a note, or send us email.