Except NSA strengthened DES against this not-yet-known-to-the-public attack (differential cryptanalysis). https://en.wikipedia.org/wiki/Data_Encryption_Standar

Except NSA strengthened DES against this not-yet-known-to-the-public attack (differential cryptanalysis). https://en.wikipedia.org/wiki/Data_Encryption_Standard#NSA's_involvement_in_the_design https://en.wikipedia.org/wiki/Data_Encryption_Standard#NSA's... https://en.wikipedia.org/wiki/Differential_cryptanalysis#History https://en.wikipedia.org/wiki/Differential_cryptanalysis#His...