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Security and Cryptography
Academic Year 2019-2020
Spring Semester

Course Information

This course aims to introduce the principles and techniques of securing computers and computer networks. The main topic of this course should help students understand cryptographic and security concepts as hash functions, key exchange protocols, encryption and decryption algorithms, digital signatures, public key certificates and infrastructure, data protection principles, secure communication, internet threats prevention. Authentication techniques and security protocols, especially those used on Internet today (considering blockchain as a breakthrough technology for cryptography and cybersecurity) will be covered towards the end of the course.


  • Professor: Sebastian-Aurelian ȘTEFĂNIGĂ
  • Address: 735 University Ave, Room WL 133, Sewanee, TN  37383-1000, USA
  • Office Phone: (+10) 931 598-1305
  • Email:
  • Course Hours: MW, 02:00 pm – 03:15 pm, WL136
  • Office Hours* (WL 133)*:
    Monday: 10:00 am - 12:00 pm;
    Monday: 05:00 pm - 06:00 pm;
    Wednesday: 10:00 am - 11:00 am;
    *or by appointment.

General Education. Course Objectives Relevant to this Course

This course will provide the main concepts in cryptography and security protocols – hash functions, key exchange protocols, encryption and decryption algorithms, digital signatures, public key certificates and infrastructure, data protection principles, secure communication, internet threats prevention. Learning Objective 5. Observing, Experimenting, and Modeling.


Course grades will be determined as follows*:

  • 10% - Class Participation/ Preparedness
  • 15% - Quizzes
  • 50% - Assignments
  • 15% - Midterm Exam
  • 10% - Final Exam
*BONUS Materials will be provided later for up to 10%!

Grading Scale

4.0 A 100–93 (Exceptional work)
3.7 A- 92–90
3.3 B+ 89–87 (More than adequate work)
3.0 B 86–83
2.7 B- 82–80
2.3 C+ 79–77 (Adequate work)
2.0 C 76–73 (Less than adequate)
1.7 C- 72–70
1.3 D+ 69–67 (Deficient work)
1.0 D 66–63
0.7 D- 62–60
0 F 59–00 (Failure to accomplish task)
Late Work Policy*:

Time management is a challenging part of college life. I know you are busy and have other obligations, courses etc. Still, out of respect for this course’s objectives and our time together, it is important that you hand in your work on time. Should you need turn in any of your assignments after the deadline, I will apply the following grade penalty:

  • 1 to 24 hours (1 day) late: I will deduct 10 points
  • 24 to 48 hours (2 days) late: I will deduct 15 points
  • 48 to 72 hours (3 days) late: I will deduct 20 points
  • More than 72 hours late: I will deduct at least 25 points
  • If you know you will have difficulty meeting a deadline, I strongly advise you to come talk with me about this in person during office hours.

    * Even if I have granted you an extension, I will not accept any assignment after the last day of classes. This is the absolute final deadline for any work, apart from the final exam, produced in my class.


    It is very important that you plan to attend all classroom sessions. If you miss a class, it is your responsibility to consult the online schedule and get notes from a peer, note that you are allowed to miss THREE classes without penalty. Class meetings are where we will discuss and work on code. Because these discussions are somewhat driven by student questions and concerns, there is no guarantee they will be covered in the same detail in your assignments or readings. Attendance is therefore required and an important factor in doing well in the class.

Weekly Topics

Selected Bibliography*: Additional readings*: Additional readings will also be provided as needed. They will be available on our Google Classroom course page. The students are responsible for all the assigned readings.

Academic Information

Academic Honesty

You agreed to follow the Honor Code when you matriculated. All forms of academic dishonesty, including plagiarism, are violations of the Honor Code and will be treated as such. If you ever have a question about an assignment or need additional help, please ask for assistance rather than jeopardize your academic career.
Discussion of concepts is encouraged, but, unless otherwise specified, all assignments must be done on your own. If you use a source other than the text (e.g., another book or a person), reference it. The Honor Code applies to all examinations and programs. Plagiarism is copying or imitating the language and thoughts of others, whatever the medium (computer program or written paper). All work on the exams and the pledged programs must be done individually.

ADA Statement

The University of the South is committed to fostering respect for the diversity of the University community and the individual rights of each member of that community. In this spirit, and in accordance with the provisions of Section 504 of the Rehabilitation Act of 1973 and the Americans with Disabilities Act (ADA), the University seeks to provide students with disabilities with the reasonable accommodations needed to ensure equal access to the programs and activities of the University. Any student with a documented disability needing academic adjustments is requested to speak with Student Accessibility Services and the instructor, as early in the semester as possible. If you have already requested accommodations, it is your responsibility to present your instructor with a copy of your academic accommodations letter from Student Accessibility Services which is located in Office of the Dean of Students (931.598.1229). Accommodations will not be provided without this documentation, and accommodations cannot be applied retroactively. Additional information about accommodations can be found here.

The Writing Center

The Writing Center, located on the main floor of duPont Library, provides objective peer support to Sewanee students who seek assistance with their writing projects. The student tutors can help at any stage in the writing process, including topic development, rough drafts, final drafts, and revisions. Students should bring a copy of the professor's written instructions to the meeting. The Writing Center will not accept papers that are dropped off.‌

The Center for Speaking and Listening

The Center for Speaking and Listening, located on the main floor of duPont Library, provides peer support to Sewanee students who seek assistance with their presentations.‌

Research Help Center

The Research Help Center in duPont Library is available for all of your research paper, project, and presentation needs. Our librarians can help with each stage of the research process, including topic selection and narrowing, outlining, finding resources, interpreting academic resources, avoiding plagiarism, and integrating research into your paper or presentation. Walk-ins are welcome, but appointments with a research expert are strongly encouraged. You can find more details and sign up for appointments here .

Title IX matters

Sexual misconduct is a violation of federal Title IX law and University policy. Disclosure of sexual misconduct to University faculty, staff, or student leaders (i.e. proctors) is not confidential and these individuals are required to make reports, including names and circumstances, to the University’s Title IX Coordinator. To report incidents of sexual misconduct, please file a report at or contact the Title IX Coordinator (Dr. Sylvia Gray, For more information on mandatory reporting please see the Mandatory Reporter Policy . For resources on support or confidential disclosure, please refer to the Sexual Misconduct Policy.

Wellness Center resources

As a student, you may experience a range of challenges that can interfere with learning, such as stress, strained relationships, increased anxiety, substance misuse, mood changes, difficulty concentrating, and/or lack of motivation. These mental health concerns or stressful events may diminish your academic performance and/or reduce your ability to participate in daily activities. Free counseling, psychological, and psychiatric services are available at the University Wellness Center, and treatment does work. You can learn more about confidential mental health services available on campus here .

Electronic Devices Policy
Please turn off the ringer on your cell phone and put it entirely away BEFORE class begins. No texting or responding to personal emails while class is in session. In general, my strong preference is that you do not use laptops or other electronic devices in class. However, you may use a laptop, ipad or kindle (…) to take notes and/or to pull up electronic copies of assigned readings for class discussion and work. Please do not use your iphone or any electronic device to record our class sessions.

Course announcements

  1. [03/23/20, 12:00 pm] Dear students, you can find HERE the Remote Instruction Support for CS415!
  2. [01/15/20, 8:00 am] The course materials will be available via Google Classroom using the password code provided during the first week of classes!


Based on the feedback received from the class participants the instructor reserved the right to adjust the topics and augment the content of the covered subjects!