Tag
8 articles with this tag.
Camellia is the cipher that stands next to AES in international standards. Learn how this Japanese Feistel design combines byte S-boxes, a linear mixing layer, and key-dependent FL layers to match AES-level security.
16 min read
CAST-128, also called CAST5, was the default cipher in some versions of PGP and GnuPG. Learn how its three alternating round functions, huge 8x32-bit S-boxes, and key-dependent rotations work, and why its 64-bit block now limits it.
25 min read
GOST 28147-89 was the Soviet Union's answer to DES. Learn how its 32-round Feistel design works, why the standard left the S-boxes undefined, and how the modern Magma cipher fixed that.
14 min read
SM4 is China's national block cipher standard, a 32-round design that updates one 32-bit word at a time. Learn how its byte S-box, rotate-and-XOR mixing, and compact key schedule work, and where the cipher is used.
13 min read
TEA is a block cipher small enough to write in a few lines of code, and XTEA is its repaired successor. Learn how shifts, additions, and XORs make a working cipher, and how a flaw in TEA's key handling led to a famous console hack.
14 min read
Bruce Schneier designed Blowfish as a free, fast alternative to DES, with a distinctive twist: its S-boxes are rebuilt from the encryption key through a key schedule that starts from the digits of pi. Learn how it works, with every value shown, and why it's still found in legacy systems today.
21 min read
The Data Encryption Standard ruled cryptography for over two decades. Learn how its Feistel network works, why its 56-bit key ultimately doomed it, and why it still matters as the foundation for 3DES and AES.
10 min read
Twofish was Bruce Schneier's answer to Blowfish's biggest weakness, and one of the five finalists in the competition that chose AES. Learn how its key-dependent S-boxes, MDS matrix, and Pseudo-Hadamard Transform work, with every value of a real test vector shown.
32 min read
