AssessmentClass participation15%Project on classical ciphers20%Group work on cryptanalysis10%Written test25%RSA10%Quantum crypto & Coding Theory20%

Introduction to CryptographyCryptography is the study of message secrecy.

Effective cryptography is an essential tool for the protection of privacy & confidential information.

In this course, we will study the development of this secret art from the ancient times to the modern era, learn some classical ciphers, a modern cryptosystem, and certain aspects of Coding Theory.

Basic DefinitionsCryptographythe art of creating & writing secret codes.

Cryptanalysisthe art of codebreaking.

Cryptologycryptography + cryptanalysis

Encryptionprocess of converting readable information (plaintext) into unreadable gibberish (ciphertext)

Decryptionreverse of encryption

Cipherthe method used in encryption & decryption.

Typing in Secret MessagePlaintextReceiving Secret MessagePlaintextTransmitting Secret MessageCiphertextEncryptionDecryptionStealing Secret MessageCiphertextFigure 1:Illustration of processes in CryptographyHacker(Doing Cryptoanalysis)

Development of Cryptography(Group Work)Research on the development of cryptography from 1900 BC to the 21st century and fill up the timeline of cryptography with the major events that took place or ciphers that were invented.

Read up on the ciphers you come across in your research and other classical ciphers.

Your group score will determine the order in which you get to choose the topic for your project, i.e. the group with the highest score gets to choose first.

How does the Atbash cipher work?Ans: The first letter of the alphabet is replaced with the last, the second with the second last, and so on.

Explain how the Scytale cipher works.Ans: The sender and receiver make two round pieces of wood exactly alike in length and thickness. These pieces of wood are called scytales. When a message needs to be sent, the sender winds a scroll of long and narrow parchment around his scytale, leaving no vacant space thereon. The message is then written, the parchment taken off and sent. To read the message, the receiver needs to rewind the parchment around his own scytale.

In which country was the first Black Chamber formed?Ans: France!

Who is the author of the worlds first printed book on cryptography?Ans: Johannes Trimethius, a German-born abbott

The first telegraph line was built in 1844, and stretched a distance of nearly 40 miles between Baltimore, Maryland and Washington, D.C. Messages sent using the telegraph were encrypted using the _________________ (name the cipher)?Ans: Morse code

Name the person who invented the first Enigma machine.Ans: Dr Arthur Scherbius

The ADFGX cipher was used by Germany in World War I. What is the name of the French cryptographer who managed to crack the cipher?Ans: Georges-Jean Painvin

During the Second World War, Japan started to encode high-level diplomatic messages using a machine known as the 97-shiki oobun Inji-ki, which was also called the ___________.Ans: Purple machine

Do research on one of the following classical ciphers and prepare a 10-15 min presentation on- the history and development of the cipher- how to use the cipher- pros and cons of the cipher

Classical ciphers are classified into transposition and substitution ciphers. Choose one of the following ciphers to work on.

Rail Fence Cipher (Group 2) Caeser Cipher (Group 3) Playfair Cipher (Group 4) Pigpen Cipher (Group 1)