QTS_Unit3_Question 2


The earliest evidence of the use of cryptography is in non-standard hieroglyphs found on ancient Egyptian statues (about 4500 years ago). The symbols appear not to serve the purpose of conveying secret information but seem to be intended to evoke mysticism, curiosity or even amusement for the viewer.

The ancient Greeks are also known to have used cryptographic techniques (such as cipher sticks). The cipher stick of the Greeks was one of the first tools in cryptography.

Classic cryptography example:

Classical encryption works on an alphabetical basis, done by hand or some simple mechanical machine Classical encryption is vulnerable to ciphertext attacks, or does not require specific details of the coding system using frequency analysis tools.

The classical encryption methods are mainly based on permutation ciphers and substitution ciphers.

– The substitution cipher uses the characters to be replaced in a regular manner in the message. For example, the sentence “I am Mr. Enigma from” is replaced by “This is morning star“.

However, encryption only flourished from the 1800s onwards thanks to the application of mathematics and especially from the 20th century, encryption has made great progress thanks to the development of computer science and technology. information.

– In 1976, the DES (Data Encryption Standard) encryption standard was recognized and widely used by the US national security agency.

– In 2000, the AES (Advanced Encryption Standard) encryption standard was approved. In 1977, three scientists Ronald Rivest, Adi Shamir, and Leonard Adleman introduced the RSA public key encryption algorithm.

+ There are no comments

Add yours