block-cipher
A type of cryptosystem that encrypts data in fixed-size blocks, exemplified by Feistel's Lucifer cipher, which processes plaintext in chunks rather than as a continuous stream.
2 chapters across 2 books
Crypto (2001)Steven Levy
The chapter discusses the introduction and controversy surrounding the Data Encryption Standard (DES) announced by the National Bureau of Standards in 1975, highlighting concerns by cryptographers Martin Hellman and Whit Diffie about the NSA's involvement and the insufficient 56-bit key length that made DES vulnerable to brute-force attacks. It also traces the origins of DES to IBM researcher Horst Feistel, who developed the Lucifer cipher, a strong block cipher designed to protect individual privacy against database intrusions, emphasizing the tension between national security secrecy and the need for public cryptographic standards.
Artificial Life: How Computers Are Transforming Our Understanding of Evolution and the Future of Life (2001)Steven Levy
This chapter explores the origins and controversies surrounding the Data Encryption Standard (DES), highlighting the skepticism of cryptographers Martin Hellman and Whit Diffie about its 56-bit key length and potential NSA influence. It traces the development of DES back to IBM researcher Horst Feistel, who designed the Lucifer cipher with privacy protection as a key motivation, emphasizing the tension between government secrecy and individual privacy in cryptography.