bruteforce attack exhaustivesearch Electronic Code Book ECB Electronic
只知密文攻擊 • 暴力攻擊(brute-force attack)或 徹底搜尋金鑰(exhaustive-search)
電子編碼本模式 Electronic Code. Book (ECB)
電子編碼本模式 Electronic Code. Book (ECB) • Patterns at the block level are preserved. • The block independency creates opportunities for Eve to exchange some ciphertext blocks without knowing the key. • No error propagation • Suit for parallel processing, random access
密文區塊鏈結模式 Cipher Block Chaining (CBC)
密文區塊鏈結模式 Cipher Block Chaining (CBC) • Patterns at the block level are not preserved. • Single error propagation • Encryption cannot parallel processing • random access decryption needs previous block
密文回饋模式 Cipher Feed. Back (CFB)
密文回饋模式 Cipher Feed. Back (CFB) • Suit for smaller size plaintext • As a stream cipher • Patterns at the block level are not preserved. • Error propagation • Encryption cannot parallel processing
輸出回饋模式 Output Feed. Back (OFB)
輸出回饋模式 Output Feed. Back (OFB) • Suit for smaller size plaintext • As a stream cipher • Patterns at the block level are not preserved. • No Error propagation • Encryption and decryption cannot parallel processing
計數器模式 Counter (CTR) Mode
計數器模式 Counter (CTR) Mode • Suit for smaller size plaintext • As a stream cipher • Patterns at the block level are not preserved. • No Error propagation • Parallel processing
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