Mezue ahịrịokwu na-esonụ: Na Bletchley Park ọ rụrụ ọrụ na cryptanalysis nke Enigma ciphers ruo ọnwụ ya na 1943. Ọ wuru otu ahụ ma chọpụta usoro nke mebiri Enigma Naval nke Ịtali, na-emepụta ọgụgụ isi nke e ji nweta mmeri ndị Allied na
Agha nke Cape Matapan. Na 1941 Knox mebiri Abwehr Enigma. Ka ọ na-erule ngwụcha nke agha ahụ, ndị ọrụ ọgụgụ isi Knox agbasawo 140,800 Abwehr decrypts, gụnyere ọgụgụ isi dị mkpa maka D-Day.