Skipjack is a block cipher developed by the US National Security Agency in 1987, first reviewed in 1993 and declassified in 1998. Skipjack is a block cipher that is designed to perform the encryption functionality of the clipper chip whereas a separate Law Enforcement Access Field (LEAF) mechanism was used to provide the escrow functionality. The algorithm was generally regarded with suspicion as it was initially classified before a small number of security experts were allowed to review it in 1993, in 1998 the security community independently discovered the design principles of the cipher and it was declassified.
Skipjack
