Ihe atụ, ntinye "011011" nwere mpụta mpụga "01" na mpụga mpụga "1101"; mmepụta kwekọrọ na ya ga-abụ "1001". The 8 S-igbe nke DES bụ isiokwu nke ọmụmụ siri ike ruo ọtụtụ afọ n'ihi nchegbu na a backdoor <unk> a vulnerability mara naanị ya emepụta <unk> nwere ike a kụrụ na cipher. The S-igbe imewe ibiere e mesịrị bipụtara (na Coppersmith 1994) mgbe ọha rediscovery nke differential cryptanalysis na-egosi, na ha na e jiri nlezianya tuned dịkwuo iguzogide megide a kpọmkwem. Biham na Shamir chọpụtara na ọbụna obere mgbanwe ka a DES-igbe nwere ike n'ụzọ dị ịrịba ama na-ehulata na-eguzogide megide a kpọmkwem. E nwere ihe ọ bụla nnyocha e mere na-echepụta ihe ọ bụla ntinye S-igbe, ebe a na-aghọta ihe dị ukwuu banyere ọrụ nke 4-bit na-arụ ọrụ nke S-igbe, ebe a na-emepụta ihe dị ukwuu nke ọma karịa ihe ọ bụla ntinye ntinye S-igbe, na-
ahọpụta ahịrị site na iji mpụga abụọ bits (nke mbụ na nke ikpeazụ bits), na kọlụm site na iji n'ime anọ bit