Ciphertext(usman 57, humza-34)

558 views

Published on

Not completed yet

Published in: Education, Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
558
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
25
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Ciphertext(usman 57, humza-34)

  1. 1.  In cryptography, ciphertext is the result of encryption performed on plaintext using an algorithm, called a cipher.
  2. 2. Cryptography began thousands of years ago.Early 20th century, the invention of complex mechanical and electromechanical machines.
  3. 3. Throughout history, the need for secrecyhas been important.Abu Yusuf Ya’qub ibn e Ishaaq Al-Kindi wasthe first to De-Cipher an encryptedmessage.
  4. 4. Historical pen and paper ciphers used in the past are sometimes known as classical ciphers. They include:Substitution cipher: the units of plaintext are replaced with ciphertext (Caesar cipher)Transposition cipher: the ciphertext is a permutation of the plaintext (Rail fence cipher)Polyalphabetic substitution cipher: a substitution cipher using multiple substitution alphabets (Vigenère cipher and Enigma machine)Permutation cipher: a transposition cipher in which the key is a permutationPrivate-key cryptography (symmetric key algorithm): the same key is used for encryption and decryptionPublic-key cryptography (asymmetric key algorithm): two different keys are used for encryption and decryption

×