Advanced Encryption Standard Algorithm HD
TABLE OF CONTENT 01 03 Encryption and Decryption 02 Demo 04 Cryptography AES
CRYPTOGRAPHY Cryptography is the science and study of methods of protecting data in computer and communication systems from unauthorized disclosure and modification.
QUOTE Here’s a quote from a famous person “Cryptography is the ultimate form of nonviolent direct action” —Julian Assange
What is Encryption and Decryption? ★ Encryption is the process of translating plain text data (plaintext) into something that appears to be random and meaningless (ciphertext). ★ Decryption is the process of converting ciphertext back to plaintext.
Why use Encryption ? Encryption is important because it allows you to securely protect data that you don't want anyone else to have access to.
DEFINITION OF CONCEPTS Private Key A private key, also known as a secret key, is a variable in cryptography that is used with an algorithm to encrypt and decrypt code. Public Key Everyone else, who wants to communicate with the Sender is given a key called the Public Key. Symmetric Encryption Symmetric Encryption is when a secret key is leveraged for both encryption and decryption functions. Asymmetric Encryption Anyone can encrypt messages using a public key, but only the holder of the paired private key can decrypt such a message. 01 03 02 04
Advanced Encryption Standard It is a symmetric block cipher algorithm chosen by the U.S. government to protect classified information and is implemented in software and hardware throughout the world to encrypt sensitive data. It was intended to be easy to implement in hardware and software, as well as in restricted environments.
CREDITS: This presentation template was created by Slidesgo, including icons by Flaticon, and infographics & images by Freepik Bit 0 or 1 1 byte = 8 bits 1 word = 4 bytes 1 block = 4 words State ( 4×4) 16 bytes Stores intermediate result. Rounds Size of keys 10 128 12 192 14 256 It has 10/12/14 rounds. Where block size 128 bits = 16 byes (4 words). No. of keys generated = N + 1
INPUT ARRAY (4X4) 4 Words 128 bits 16 bytes 1 byte STATE ARRAY (4X4) S0,0 S1,0 S2,0 S3,0 S0,1 S1,1 S2,1 S3,1 S0,2 S1,2 S2,2 S3,2 S0,3 S1,3 S2,3 S3,3 3rd byte of 0th word W0 W1 W2 W3
KEY K0 K4 K8 K12 K1 K5 K9 K13 K2 K6 K10 K14 K3 K7 K11 K15 W0 W1 W2 W3 W0 W1 W2 …… W42 W43 Key Expansion Algo 44 words
Structure of each round at the encryption site
SUBSTITUTION AES uses substitution. Substitution is done for each byte. Only one table is used for transformation of bytes that means if two bytes are same then transformation is also same. SUBBYTES The first transformation, SubBytes, is used at the encryption site. To substitute a byte, we interpret the byte as two hexadecimal digits. 1st hexadecimal digit = Row 2nd hexadecimal digit = Column
Permutation Another transformation found in a round is shifting, which permutes the bytes. In the encryption, the transformation is called ShiftRows..
MIXING
Take each word or column i.e. 4 bytes or 4x1 matrix and multiply it with the constant matrix The output is 4x1 matrix of 4 bytes and is stored in output or state matrix.
Key Adding AddRoundKey proceeds one column at a time. AddRoundKey adds a round key word with each state column matrix; the operation in AddRoundKey is matrix addition.
Conclusion ● Cryptography ● Encryption and Decryption ● Private key, public key, Symmetric Encryption, Asymmetric Encryption. ● What is aes? ● General design of aes
PROCESS Add roundkey Subbyte Shift rows mixing
● Cryptography and network security (fifth edition) by William Stallings. ● wikipedia References
ThankYou

Advanced Encryption Standard Algorithm

  • 1.
  • 2.
    TABLE OF CONTENT 0103 Encryption and Decryption 02 Demo 04 Cryptography AES
  • 3.
    CRYPTOGRAPHY Cryptography is thescience and study of methods of protecting data in computer and communication systems from unauthorized disclosure and modification.
  • 4.
    QUOTE Here’s a quotefrom a famous person “Cryptography is the ultimate form of nonviolent direct action” —Julian Assange
  • 5.
    What is Encryption and Decryption? ★ Encryptionis the process of translating plain text data (plaintext) into something that appears to be random and meaningless (ciphertext). ★ Decryption is the process of converting ciphertext back to plaintext.
  • 6.
    Why use Encryption? Encryption is important because it allows you to securely protect data that you don't want anyone else to have access to.
  • 7.
    DEFINITION OF CONCEPTS PrivateKey A private key, also known as a secret key, is a variable in cryptography that is used with an algorithm to encrypt and decrypt code. Public Key Everyone else, who wants to communicate with the Sender is given a key called the Public Key. Symmetric Encryption Symmetric Encryption is when a secret key is leveraged for both encryption and decryption functions. Asymmetric Encryption Anyone can encrypt messages using a public key, but only the holder of the paired private key can decrypt such a message. 01 03 02 04
  • 8.
    Advanced Encryption Standard It isa symmetric block cipher algorithm chosen by the U.S. government to protect classified information and is implemented in software and hardware throughout the world to encrypt sensitive data. It was intended to be easy to implement in hardware and software, as well as in restricted environments.
  • 9.
    CREDITS: This presentationtemplate was created by Slidesgo, including icons by Flaticon, and infographics & images by Freepik Bit 0 or 1 1 byte = 8 bits 1 word = 4 bytes 1 block = 4 words State ( 4×4) 16 bytes Stores intermediate result. Rounds Size of keys 10 128 12 192 14 256 It has 10/12/14 rounds. Where block size 128 bits = 16 byes (4 words). No. of keys generated = N + 1
  • 10.
    INPUT ARRAY (4X4) 4Words 128 bits 16 bytes 1 byte STATE ARRAY (4X4) S0,0 S1,0 S2,0 S3,0 S0,1 S1,1 S2,1 S3,1 S0,2 S1,2 S2,2 S3,2 S0,3 S1,3 S2,3 S3,3 3rd byte of 0th word W0 W1 W2 W3
  • 11.
  • 12.
    Structure of each roundat the encryption site
  • 13.
    SUBSTITUTION AES uses substitution.Substitution is done for each byte. Only one table is used for transformation of bytes that means if two bytes are same then transformation is also same. SUBBYTES The first transformation, SubBytes, is used at the encryption site. To substitute a byte, we interpret the byte as two hexadecimal digits. 1st hexadecimal digit = Row 2nd hexadecimal digit = Column
  • 15.
    Permutation Another transformation foundin a round is shifting, which permutes the bytes. In the encryption, the transformation is called ShiftRows..
  • 17.
  • 18.
    Take each wordor column i.e. 4 bytes or 4x1 matrix and multiply it with the constant matrix The output is 4x1 matrix of 4 bytes and is stored in output or state matrix.
  • 19.
    Key Adding AddRoundKey proceedsone column at a time. AddRoundKey adds a round key word with each state column matrix; the operation in AddRoundKey is matrix addition.
  • 21.
    Conclusion ● Cryptography ● Encryptionand Decryption ● Private key, public key, Symmetric Encryption, Asymmetric Encryption. ● What is aes? ● General design of aes
  • 22.
  • 23.
    ● Cryptography andnetwork security (fifth edition) by William Stallings. ● wikipedia References
  • 24.