Welcome to Symmetric Cryptography!
Symmetric cryptography relies on shared secret key to ensure message confidentiality, so that the unauthorized attackers cannot retrieve the message. The course describes substitution and transposition techniques, which were the bases for classical cryptography when the message is encoded in natural language such as English. Then, we build on product ciphers (using both substitution and transposition/permutation) to describe modern block ciphers and review the widely used cipher algorithms in DES, 3-DES, and AES. Lastly, we enable the use of block ciphers to support variable data length by introducing different modes of block cipher operations in ECB, CBC, CFB, OFB, and CTR modes.
This course is cross-listed and is a part of the two specializations, the Applied Cryptography specialization and the Introduction to Applied Cryptography specialization.
Status: Encryption
Encryption
Status: Key Management
Key Management
Intermediate·Course·13 hours
Featured reviews
5.0
·Reviewed Jul 21, 2020
This course has deepened my interest in Cryptography. I am a fan of Da Vinci and ciphers. I am gonna dig a lot deeper in this. Thanks for providing the required directivity.
5.0
·Reviewed Sep 20, 2021
Very Great Course learned many things many encryption technique in depth really great contents there
4.0
·Reviewed Nov 29, 2020
This course helps in clearing all the topics in which i have doubt. I have learned new concepts from this.
5.0
·Reviewed May 22, 2020
A great learning experience. I teach Cryptography in my Institution and this course helped me gain additional insights on the course.
5.0
·Reviewed Jun 1, 2021
Good view of the basic Symmetric Crypto concepts. Theory is presented in an easy way to understand way. Professor is also super clear in his explanations. Recommended :)
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C
Chivukula
5.0
·Reviewed Jun 11, 2020
The course is well designed and highly useful to every cryptographer. The lectures are very explanatory and understandable. But the DES pseudo code assignment is somewhat difficult for non computer science people.
I
Ishan
2.0
·Reviewed Apr 17, 2020
Peer graded assignments are not good cheaters are being passed but people like me who write original content are being failed by mere 1 or two points by peers.People are literally copying codes from websites and are being graded and given certification of completion.Its really the sad truth.
E
Enrico
1.0
·Reviewed May 29, 2022
Dont bother taking this course as there are a lot of errors in the quizzes which means you cannot pass this course. Professor does not even respond to the queries in the discussion forum.
T
Tianxiang
5.0
·Reviewed Jun 4, 2020
Very good course that covers a lot of material on symmetric ciphers.
One possible area of improvement would be to cover some possible attacks specifically against symmetric ciphers. A bit of this is done when discussing the weakness of 2DES (MITM attack), which is very interesting. More of this would help reinforce the sense that cryptology is a combination of both coming up w/ better algorithms & breaking existing ones.
M
Mohanish
5.0
·Reviewed Jul 22, 2020
This course has deepened my interest in Cryptography. I am a fan of Da Vinci and ciphers. I am gonna dig a lot deeper in this. Thanks for providing the required directivity.
A
Adri
5.0
·Reviewed May 23, 2020
A great learning experience. I teach Cryptography in my Institution and this course helped me gain additional insights on the course.
Y
Yashrajsinh
5.0
·Reviewed Sep 29, 2020
Good course
R
Rohan
3.0
·Reviewed May 22, 2020
Good for fundamental understanding, but lacks mathematical foundations. So, if u get the math behind what's happening, u will enjoy the course and the quizzes. If not, for a more mathematical approach, refer NPTEL's IIT KGP Course
H
Harris
5.0
·Reviewed Nov 12, 2020
Well laid-out course! It covers the essentials of symmetric cryptography crisply. The peer-graded assignments really helped me a lot in understanding the concepts more deeply. Quizzes are good, however, the feedback on answers could have been better. Certain concepts could have been explained in a bit more detail, so it is easier to understand certain quiz questions.
A
Aryanadi
5.0
·Reviewed Dec 4, 2021
Million thanks to Sang-Yoon Chang for being great lecture for this wonderful online course. I've been learning a lot from your lectures and I will keep learning it for my future new career I am planning to achieve hopefully soon.
S
Sebastian
5.0
·Reviewed Jun 2, 2021
Good view of the basic Symmetric Crypto concepts. Theory is presented in an easy way to understand way. Professor is also super clear in his explanations.
Recommended :)
L
Luis
5.0
·Reviewed Sep 17, 2024
Great course. I'd say that the AES modes XTS and GCM should be covered too. Regardless, the course and professor is great and explains on great detail.
H
HRITIK
5.0
·Reviewed Sep 21, 2021
Very Great Course
learned many things many encryption technique in depth really great contents there
P
P.V.Lakshmi
5.0
·Reviewed Aug 4, 2020
course design is brilliant. assignment questions are wonderful. peer review , flash quiz amazing.
M
Manuel
5.0
·Reviewed Jul 19, 2020
Gives you a great explanation of the encryption algorithms and how they work
G
Gulzodaxon
5.0
·Reviewed Apr 3, 2025
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