PC1 cipher

This article is about the PC1 cipher used in the Kindle. For the permuted choice used in the DES cipher, see DES supplementary material § Permuted choice 1 (PC-1).

The PC1 cipher, also called the Kindle cipher or Pukall cipher 1, is a block cipher introduced in 1991. It is most prominently used by Amazon, Inc., for their Kindle e-book reader's DRM system.^[1]

History

The PC1 cipher was designed by Alexander Pukall in 1991.^[2][3]

Successors

Caracachs Cipher formerly known as PC3 Cipher was released in 2000.^[4] This algorithm was used by the North Korean hacker group Lazarus Group. ^[5]

PC4 was released in 2015. It's a block cipher specifically designed for DMR radio communication systems. It uses 253 rounds and the key size can vary from 8 bits to 2112 bits. The block size is 49 bits, the exact size of an AMBE+ DMR voiceframe. ^[6]