密码学基础(04) Public Key Cryptography, RSA 復大辱软件学院 LiJT
LiJT 1 密码学基础（04） Public Key Cryptography, RSA
Public Key Cryptography Principles of Public-Key Cryptosystems The rsa algorithm 復大辱软件学院 LiST
LiJT 2 Public Key Cryptography • Principles of Public-Key Cryptosystems • The RSA Algorithm
e Review: Symmetric Cipher Model Secret key shared by Secret key shared by sender and recipient sender and recipient Transmitted ciphertext Plaintext Plaintext Input Encryption algorithm Decryption algorithm output (e.g, DES) (reverse of encryption algorithm) Bob Alice 3 復大辱软件学院 LiST
LiJT 3 Review: Symmetric Cipher Model Bob Alice
ota Symmetric Cryptograph traditional symmetric/secret/single key cryptography uses one key shared by both sender and receiver if this key is disclosed communications are compromised also is symmetric, parties are equal 復大辱软件学院 LiJT
LiJT 4 Symmetric Cryptography • traditional symmetric/secret/single key cryptography uses one key • shared by both sender and receiver • if this key is disclosed communications are compromised • also is symmetric, parties are equal
ef Review: Symmetric Cipher Model Secure channel Secret key shared by Secret key shared by sender and recipient sender and recipient Transmitted ciphertext Plaintext Plaintext Input Encryption algorithm Decryption algorithm output (e.g, DES) (reverse of encryption algorithm) Bob Alice 5 復大辱软件学院 LiJT
LiJT 5 Review: Symmetric Cipher Model Secure channel Bob Alice