COSC 435: Introduction to Network Security
Fall 2021

Instructor: Prof. Benjamin E. Ujcich
Instructor Email: bu31 [at] georgetown [dot] edu
Office: St. Mary’s Hall 353

TA: Moxiao Liu
TA Email: ml1919 [at] georgetown [dot] edu

TA: Varun Uppala
TA Email: vu14 [at] georgetown [dot] edu

Room: Reiss Science Building 262
Time: Tuesdays and Thursdays 12:30 – 1:45 PM ET

Office Hours: Mondays 4:00 – 5:00 PM ET (Moxiao), Thursdays 2:00 – 3:00 PM ET (Ben), Thursdays 7:00 – 8:00 PM ET (Varun), or by appointment (see Canvas for Zoom info)

Course Description

This course introduces students to Internet security. Students will learn about current threats and defenses by examining case studies, seminal research papers, and monographs in a wide range of security areas. Topics covered include cryptography, network design fundamentals, authentication, confidentiality protocols, worms, botnets, denial-of-service attacks, firewalls, intrusion detection systems, secure routing, network privacy and anonymity, Web security, network eavesdropping, social engineering, and computer crime.

Note on sections: Undergraduate students should sign up for section 01. Graduate students should sign up for section 02. Both sections will meet at the same time and location for lectures and will share the same Canvas course page, assignments, and exams.

Textbook and Readings

  • Required reading material will be listed on the course Canvas page.
  • The optional textbook for this class is Introduction to Computer Security by Michael Goodrich and Roberto Tamassia.
  • Additional optional supplemental reading material can be found on the resources page.

Course Communications

The information on this course website is subject to change. Please check back regularly!

We will make use of the following communication methods during this course:

  • Announcements will be announced during class and posted on Canvas.
  • Lectures will be in person. Lectures will be recorded and posted later on the course Canvas page under the Panopto tab.
  • The course schedule and assignment information will be posted on this page.
  • Grades and assignment submissions will be managed through Canvas.
  • The class discussion forum will be managed through Piazza, which can also be found on the course Canvas page under the Piazza tab. Note that Piazza will often be the easiest, fastest, and most efficient way to get in contact.

If you have general questions about assignments, course content, or course logistics, please post these questions publicly in Piazza. This is an open forum, and you are encouraged to help each other.

If you have requests related to grading, solution-specific assignment questions (i.e., questions that would reveal partial or full solutions), office hour meetings (outside of the normal course office hours), or extensions, please post these questions privately in Piazza to all instructors (i.e., course instructor and TAs).

For personal or confidential issues, e-mail the course instructor directly.


See the assignments page for more information about specific assignments.


Semester grades will be weighted as follows:

  • 40%: Machine problem (MP) projects
  • 10%: Reading quizzes, security analysis report, and other assignments
  • 25%: Midterm exam
  • 25%: Final exam

Letter grade policy

Final letter grades will be based on the weighted final average, as computed using the above list. This average will be converted to a letter grade as follows:

  • A: 100% to 94.0%
  • A-: less than 94.0% to 90.0%
  • B+: less than 90.0% to 87.0%
  • B: less than 87.0% to 84.0%
  • B-: less than 84.0% to 80.0%
  • C+: less than 80.0% to 77.0%
  • C: less than 77.0% to 74.0%
  • C-: less than 74.0% to 70.0%
  • D+: less than 70.0% to 67.0%
  • D: less than 67.0% to 64.0%
  • D-: less than 64.0% to 61.0%
  • F: less than 61.0% to 0.0%

Note for graduate students enrolled in the class (section 02): According to the Graduate School policy, graduate students enrolled in the class (section 02) cannot earn D grades. Thus, any average lower than 70.0% translates to an F.

Late work policy

Due dates will be posted for all assignments and exams.

Given the hardships of taking courses during a global pandemic, the instructor may grant “no-excuse-necessary” extensions for assignments (i.e., no reason needs to be given for why the submission will be late). Please request this on Piazza in advance, or at least by the time the assignment is due. This is a difficult time for nearly everyone, and this policy is intended to help make life a bit easier for us all, under our current circumstances. That said, to keep pace with the course, it really is best if you submit assignments when they are due.

To submit an extension request on Piazza, select ‘Individual Student(s) / Instructor(s)’ under “Post To”, type ‘Instructors’ in the text box that appears, and select both the extensions folder and the assignment folder (e.g., mp1) so that the instuctors and TAs know that this is an extension request.

Regrade request policy

You may appeal to the instructor for reconsideration of a grade. The appeal must be submitted in writing on Piazza, and must be sent within three weeks (or the close of the semester, whichever is sooner) of receiving the graded assignment. Grades not appealed within this period will not be recalculated at a later date.

Note: Regrading applies to the entire assignment, which may result in the grade remaining the same, being raised, or being lowered.

To submit a regrade request on Piazza, select ‘Individual Student(s) / Instructor(s)’ under “Post To”, type ‘Instructors’ in the text box that appears, and select both the grades folder and the assignment folder (e.g., mp1) so that the instuctors and TAs know that this is a regrade request.

Ethics, Law, and University Policies

This course will include topics related computer security and privacy, including both offensive and defensive computer and network security techniques. We may cover technologies whose abuse could infringe on the rights of others. As computer scientists, we rely on the ethical use of these technologies. Unethical use includes circumvention of an existing security or privacy mechanisms for any purpose, or the dissemination, promotion, or exploitation of vulnerabilities of these services. Any activity outside the letter or spirit of these guidelines will be reported to the proper authorities and may result in dismissal from the class and possibly more severe academic and legal sanctions.

Acting lawfully and ethically is your responsibility. Carefully read the Computer Fraud and Abuse Act (CFAA), a federal statute that broadly criminalizes computer intrusion. This is one of several laws that govern “hacking.” Understand what the law prohibits.

You are required to familiarize yourself with the University’s Information Security Policy and Computer Systems Acceptable Use Policy. Enrollment in this class does not constitute a waiver of these policies. You are expected and required to obey all University policies. Talk to the instructor before conducting any network experiments.

The course follows the Departmental Honor Policy. If you are unsure whether or not a certain practice is permissible, please ask the instructor beforehand.

Your participation is subject to the University’s Policy on Audio and Video Recordings During Virtual Learning Environment. Please familiarize yourself with the full policy here.

Additional University policies can be found here.

Please familiarize yourself with the University’s COVID-19 FAQ page for questions on COVID-related policies.

Special Accommodations

If you believe that you have a disability that will affect your performance in this class, please contact the Academic Resource Center ( for further information. The center is located in the Leavey Center, Suite 335. The Academic Resource Center is the campus office responsible for reviewing documentation provided by students with disabilities and for determining reasonable accommodations in accordance with the Americans with Disabilities Act (ADA) and University policies.

Support Services

Georgetown recognizes that COVID-19 has a significant impact on everyone in the Georgetown community. Georgetown offers a variety of support services for students that can be accessed online and has put together this newsletter, which aims to provide you with information about well-being resources and virtual meetings that can connect you with mental health professionals on and off campus during this time. Below are some resources available to you:

Georgetown University and its faculty are committed to supporting survivors and those impacted by sexual misconduct, which includes sexual assault, sexual harassment, relationship violence, and stalking. Georgetown requires faculty members, unless otherwise designated as confidential, to report all disclosures of sexual misconduct to the University Title IX Coordinator or a Deputy Title IX Coordinator. If you disclose an incident of sexual misconduct to a professor in or outside of the classroom (with the exception of disclosures in papers), that faculty member must report the incident to the Title IX Coordinator, or Deputy Title IX Coordinator. The coordinator, will, in turn, reach out to the student to provide support, resources, and the option to meet. Please note that the student is not required to meet with the Title IX coordinator.

Please note that University policy requires faculty to report any disclosures about sexual misconduct to the Title IX Coordinator, whose role is to coordinate the University’s response to sexual misconduct. Georgetown has a number of fully confidential professional resources who can provide support and assistance to survivors of sexual assault and other forms of sexual misconduct. These resources include:

  • Jen Schweer, MA, LPC, Associate Director of Health Education Services for Sexual Assault Response and Prevention, 202-687-0323 or
  • Erica Shirley, Trauma Specialist, Counseling and Psychiatric Services (CAPS), 202-687-6985 or

More information about reporting options and resources can be found on the Sexual Misconduct Website.

Georgetown University is committed to creating an accessible and inclusive environment for pregnant and parenting students. Students may request adjustments based on general pregnancy needs or accommodations based on a pregnancy-related complication. Specific adjustments will be handled on a case by case basis and will depend on medical needs and academic requirements. Students seeking a pregnancy adjustment or accommodation should follow the process laid out on the Title IX website.

Discrimination based on sex, including sexual misconduct and discrimination based on pregnancy or parenting status, subverts the University’s mission and threatens permanent damage to the educational experience, careers, and well-being of students, faculty, and staff.