Understanding Symmetric Encryption & Defending Against Brute Force Attacks 🔐

In this video, I have been discussed about Symmetric encryption and its requirements, various cryptanalytic attacks, Brute force search or attack, Conditional Security and Computational Security.

All traditional schemes are symmetric / single key / private-key encryption algorithms, with a single key, used for both encryption and decryption, since both sender and receiver are equivalent, either can encrypt or decrypt messages using that common key.

Five ingredients of the symmetric cipher model:
plaintext
encryption algorithm – performs substitutions/transformations on plaintext
secret key – control exact substitutions/transformations used in encryption algorithm
ciphertext
decryption algorithm – inverse of encryption algorithm

Unconditional security would be nice, but the only known such cipher is the one-time pad (Discussed later). For all reasonable encryption algorithms, have to assume computational security where it either takes too long, or is too expensive, to bother breaking the cipher.

External link -
https://en.wikipedia.org/wiki/Kerckhoffs%27s_principle
ATM card Pin break - https://www.youtube.com/watch?v=yB82FNPoiPM