A prominent expert in the number theory Godfrey Hardy described it in the beginning of 20th century as one of the most obviously useless branches of Pure Mathematics”. Just 30 years after his death, an algorithm for encryption of secret messages was developed using achievements of number theory. It was called RSA after the names of its authors, and its implementation is probably the most frequently used computer program in the world nowadays. Without it, nobody would be able to make secure payments over the internet, or even log in securely to e-mail and other personal services. In this course we will start with the basics of the number theory and get to cryptographic protocols based on it. By the end, you will be able to apply the basics of the number theory to encrypt and decrypt messages, and to break the code if one applies RSA carelessly. You will even pass a cryptographic quest!
This course is part of the Introduction to Discrete Mathematics for Computer Science Specialization
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About this Course
Skills you will gain
- Number Theory
- Cryptography
- Modular Exponentiation
Offered by
Syllabus - What you will learn from this course
Modular Arithmetic
Euclid's Algorithm
Building Blocks for Cryptography
Cryptography
Reviews
- 5 stars68.95%
- 4 stars21.18%
- 3 stars5.57%
- 2 stars1.30%
- 1 star2.97%
TOP REVIEWS FROM NUMBER THEORY AND CRYPTOGRAPHY
I loved this course! It is unlike any I have taken before. All courses in this specialization have always included fun activities to make the taught content fun and understandable.
It was a great course which helped me learn number theory and introduced me to Cryptography.
The teaching assistants could have been more active.
Good material and presentation from the professors. Programming exercises were a bit confusing at times. Overall, short but mathematically solid course.
I cant think of any other best way of presenting cryptography to beginners. Everything presented in the course has some connection to cryptography, really enjoyed RSA quest.
About the Introduction to Discrete Mathematics for Computer Science Specialization

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