Duba wurin da ke ƙasa sannan ka amsa tambayar daga baya a cikin harshe ɗaya kamar yadda wurin yake:  Passage: Ganin shigarwar 6-bit, ana samun fitowar 4-bit ta hanyar zaɓar jere ta amfani da ƙananan ƙananan biyu (bit na farko da na ƙarshe), da kuma shafi ta amfani da ƙananan ƙananan hudu. Misali, shigarwar "011011" tana da ragowar ragowar "01" da ragowar ragowar "1101"; fitowar da ta dace za ta zama "1001".A cikin akwatunan S 8 na DES sun kasance batun nazari mai zurfi na shekaru da yawa daga damuwa cewa ƙofar baya <unk> wani rauni da aka sani kawai ga masu zanen sa <unk> za a iya dasa shi a cikin cipher. Sharuɗɗan ƙirar S-akwatin an ƙarshe an buga su (a Coppersmith 1994) bayan sake gano jama'a game da bambancin cryptanalysis, yana nuna cewa an daidaita su a hankali don haɓaka juriya ga wannan takamaiman harin. Biham da Shamir sun gano cewa ko da ƙananan gyare-gyare ga S-akwatin na iya raunana DES sosai. An yi bincike mai yawa game da ƙirar S-akwatin masu kyau, kuma an fahimci abubuwa da yawa game da amfani da su a cikin ɓangarorin ɓoye fiye da lokacin da aka saki DES. Duk wani S-akwatin inda kowane fitowar fitowar da aka samar ta hanyar aikin karkatarwa na ragowar shigarwa, kuma inda kowane haɗin layi na ragowar fitarwa shima aikin karkatarwa ne na ragowar shigarwa, shine cikakken S-akwatin.  Tambaya: Ta yaya za ka gano fitowar 4 bit?
zabar jere ta amfani da waje biyu ragowa (na farko da na karshe ragowa), da kuma shafi ta amfani da ciki hudu ragowa