CS 4700 / CS 5700 - Network Fundamentals

General Information

Professors: Christo Wilson and Alan Mislove
Room: Shillman Hall 320
Time: Wednesdays, 6-9pm
Office Hours: TBA
Teaching Assistant: Le Chen
TA Email: leonchen@ccs.neu.edu
Lab Hours: 10-12pm, Fridays, WVH Lab Area
Class Forum: On Piazza
Paper List: Here

Course Description

Computer networking is a rapidly advancing field, and the Internet is already an integral part of society. It is therefore important for computer scientists and computer engineers to be familiar with the fundamentals of computer networking. This course will focus on the architecture, algorithms, and protocols of the Internet. Topics include local area networking, routing, congestion control, network security, and applications such as peer-to-peer and content distribution networks. This course will be systems oriented, and students will work on hands-on projects to learn how to build and understand Internet applications.


The official prerequisites for this course are CS 3600 and CS 2600 (or equivalents). This course is systems oriented, so I expect you to understand the basics of computer architecture and operating systems, and to have experience implementing non-trivial systems-type projects. Basic knowledge of the Unix command line is also essential. You should know how to write code using emacs/vim, write a makefile, compile/debug code, check for running processes, kill runaway processes, and create compressed archives.

Class Forum

The class forum is on Piazza. Why Piazza? Because they have a nice web interface, as well as iPhone and Android apps. Piazza is the best place to ask questions about projects, programming, debugging issues, exams, etc. I will open up discussion boards for each lecture right before class, so if you have questions while in lecture feel free to post them. In order to keep things organized, please tag all posts with the appropriate hashtags, e.g. #lecture1, #project3, etc. I will also use Piazza to broadcast announcements to the class. Bottom line: unless you have a private problem, post to Piazza before writing me/the TA an email.

Schedule, Lecture Slides, and Assigned Readings

Date Slides Piazza Tag Textbook Readings Comments
Sept. 4 Intro, History,
Architecture, C Sockets
#lecture1 §1.1-1.5 Join Piazza
Sept. 11 Physical Layer,
Data Link Layer, Bridging
#lecture2 §2.1-2.8, 3.1 Cla88, SRC84 Proj. 1 Out
Sept. 18 Network Layer,
Intra-domain Routing
#lecture3 §3.2, 3.3, 4.1.3 SG04, SIG+02 Proj. 1 due, Proj. 2 out
Sept. 25 Inter-domain Routing #lecture4 §4.1-4.4 LAA+01, GM+04,
Oct. 2 Transport Layer,
Congestion Control
#lecture5 §2.5, 5.1, 5.2, 6.3 CK74, Jac88, CJ89 Proj. 2 Due, Proj. 3 Out
Oct. 9 DNS, NAT, QoS #lecture6 §6.5, 9.3.1 B+95, ZDE+93, SZ99
Oct. 16 Midterm #midterm
Oct. 23 Router Supported Congestion Control,
Next Generation Transport
#lecture7 §6.2, 6.4 KHR02, ACK+05,
FJ93, DKS89
Proj. 3 Due, Proj. 4 Out
Oct. 30 Datacenters #lecture8 AGM+10, WBKR11,
Nov. 6 P2P, Bittorrent #lecture9 SGG+03, C+03,
Nov. 13 Overlay Networks #lecture10 §9.4 SMK+01, DH+07 Proj. 4 Due, Pro. 5 Out
Nov. 20 Malware,
Botnets, Spam
#lecture11 §8.1-8.6 SEV+04, FPPS+07,
KKLE+08, SCCG+09
Nov. 27 No Lecture: Thanksgiving Holiday
Dec. 4 Anonymous Communications #lecture12 DMS+04, WA+04,
Proj. 5 Due
Dec. 6 Final Exam #final 10:30am-1:30pm,
Location: Richards Hall 200


The focus of this course will be on reading important papers from the networking research community. Thus, I do not require that you get a textbook. However, a textbook may be useful if you are not totally comfortable with network fundamentals, or if you just want to have a handy reference book. Officially, the textbook for the course is:

Computer Networks: A Systems Approach, 4th Edition by Larry Peterson and Bruce Davie, Morgan Kaufmann.

There is also a supplement:

TCP/IP Sockets in C by Jeff Donahoo and Ken Calvert, Morgan Kaufmann.

Also recommended, for reference:

Computer Networking: A Top-Down Approach Featuring the Internet. by Jim Kurose and Keith Ross, Addison-Wesley.

Reading and Participation

As previously mentioned, a large component of this course will be reading important papers from the networking research community. Some of these papers are classics: older, but intrumental in guiding the design of today's networks. Other papers will be more contemporary, and focus on improving existing networks, or even replacing them entirely. All the papers can be found here.

Several papers will be assigned as reading before each lecture. Two people will be chosen at random to lead discussions on each paper: one championing the work, the other criticizing it. A discussion thread will be opened on Piazza for each paper, and the discussion leaders must post 1) detailed summaries of the paper, and 2) the strengths (for champions) or weaknesses (for critics) of the paper. Everyone in the class is encouraged to join these discussions. Each student will be assigned to champion one paper, and critique another, i.e. each student will lead the discussion of two papers during the course.

During class, students will be called at random to briefly summarize papers. Thus, although attendance in lectures is not required, if you get called and you are not present (or you haven't read the paper), then you are busted.

5% of your final grade will be based on participation. If you post on Piazza when you are the assigned discussion leader for a paper, and summarize papers when called in class, then you will receive full marks for participation.


There will be five programming projects throughout the semester. Programming projects are due at 11:59:59pm on the specified date. We will use a turn-in script to create a compressed archive of the project files, timestamp them, and submit them for grading. These projects require significant design and coding, hence students are recommended to start early!

Assignment Description Due Date Piazza Tag
Project 1 Socket Basics September 18 #project1
Project 2 Web Crawler October 2 #project2
Project 3 TCP Simulation in NS-2 October 23 #project3
Project 4 Raw Sockets November 13 #project4
Project 5 Cheating Bittorrent Client December 4 #project5

You will form groups of two people (possibly three, if necessary) to do the projects. I will allow you to form your own groups; if you are having trouble finding a partner, post a notice to Piazza. As you are free to choose your partner(s), I will not be sympathetic to complaints at the end of the semester about how your group-mates did not do any work. All group members should be involved in all major design decisions, and groups should develop a programming plan that can be effectively parallelized. You may switch groups between programming projects.

As the graduate versions of projects may contain extra requirements, it is strongly recommended (but not required) that groups be formed of either all undergraduates or graduate students. If any of the group members are graduate students, the project will be graded as a graduate student project.


There will be one midterm and one final. All exams will be closed book and closed notes, and computers are not allowed nor is any access to the Internet via any device. The exams will cover material from lectures, readings, and the projects. The final will be cumulative, so review everything!


Projects: 4%, 8%, 12%, 16%, 20%
Midterm and Final: 15% and 20%
Participation: 5%

Each project will include a breakdown of how it will be graded. Some projects may include extra credit components that can boost your grade above the maximum score :)

To calculate final grades, I simply sum up the points obtained by each student (the points will sum up to some number x out of 100) and then use the following scale to determine the letter grade: [0-60] F, [60-62] D-, [63-66] D, [67-69] D+, [70-72] C-, [73-76] C, [77-79] C+, [80-82] B-, [83-86] B, [87-89] B+, [90-92] A-, [93-100] A. I do not curve the grades in any way.

Any requests for grade changes must be made within seven days of when the work was returned. To ask for a regrade, send an email to the instructor that specifies (a) the problem or problems you want to be regraded, and (b) for each of these problems, why do you think the problem was misgraded.

Requests for Regrading

In this class, we will use the Coaches Challenge to handle requests for regrading. Each student is allotted two (2) challenges each semester. If you want a project or a test to be regraded, you must come to the professors office hours and make a formal challenge specifying (a) the problem or problems you want to be regraded, and (b) for each of these problems, why you think the problem was misgraded. If it turns out that there has been an error in grading, the grade will be corrected, and you get to keep your challenge. However, if the original grade was correct, then you permanently lose your challenge. Once your two challenges are exhausted, you will not be able to request regrades. You may not challenge the use of slip days, or any points lost due to lateness.

Note that, in the case of projects, all group members must have an available challenge in order to contest a grade. If the challenge is successful, then all group members get to keep their challenge. However, if the challenge is unsuccessful, then all group members permanently lose one challenge.

Late Policy

For programming projects, we will use flexible slip days. Each student is given ten (10) slip days for the semester. You may use the slip days on any project or homework during the semester in increments of one day. For example, you can hand in one project ten days late, or one project two days late and two projects four days late. You do not need to ask permission before using slip days; simply turn in your assignment late and the grading scripts will automatically tabulate any slip days you have used.

Slip days will be deducted from each group member's remaining slip days. Keep this stipulation in mind: if one member of a group has zero slip days remaining, then that means the whole group has zero slip days remaining.

After you have used up your slip days, any project handed in late will be marked off using the following formula:

Original_Grade * (1 - ceiling(Seconds_Late / 86400) * 0.2) = Late_Grade

In other words, every day late is 20% off your grade. Being 1 second late is exactly equivalent to being 23 hours and 59 minutes late. Since you will be turning-in your code on the Khoury College machines, their clocks are the benchmark time (so beware clock skew between your desktop and Khoury College if you're thinking about turning-in work seconds before the deadline). My late policy is extremely generous, and therefor we will not be sympathetic to excuses for lateness.

Cheating Policy

It's ok to ask your peers about the concepts, algorithms, or approaches needed to do the assignments. We encourage you to do so; both giving and taking advice will help you to learn. However, what you turn in must be your own, or for projects, your group's own work. Looking at or copying code or homework solutions from other people or the Web is strictly prohibited. In particular, looking at other solutions (e.g., from other groups or students who previously took the course) is a direct violation. Projects must be entirely the work of the students turning them in, i.e. you and your group members. If you have any questions about using a particular resource, ask the course staff or post a question to the class forum.

All students are subject to the Northeastern University's Academic Integrity Policy. Per Khoury College policy, all cases of suspected plagiarism or other academic dishonesty must be referred to the Office of Student Conduct and Conflict Resolution (OSCCR). This may result is deferred suspension, suspension, or expulsion from the university.

Accommodations for Students with Disabilities

If you have a disability-related need for reasonable academic accommodations in this course and have not yet met with a Disability Specialist, please visit www.northeastern.edu/drc and follow the outlined procedure to request services. If the Disability Resource Center has formally approved you for an academic accommodation in this class, please present the instructor with your "Professor Notification Letter" at your earliest convenience, so that we can address your specific needs as early as possible.

Title IX

Title IX makes it clear that violence and harassment based on sex and gender are Civil Rights offenses subject to the same kinds of accountability and the same kinds of support applied to offenses against other protected categories such as race, national origin, etc. If you or someone you know has been harassed or assaulted, you can find the appropriate resources here.