Rịba ama amaokwu a dị n'okpuru ma zaa ajụjụ ahụ mgbe e mesịrị n'otu asụsụ ahụ dị ka amaokwu ahụ:  Passage: Ọdịdị nke ngalaba na-agbadata site n'aka nri gaa n'aka ekpe; akara ọ bụla n'aka ekpe na-akọwapụta nkewa, ma ọ bụ subdomain nke ngalaba dị n'aka nri. Dịka ọmụmaatụ, ihe nlele aha na-akọwa ngalaba ngalaba nke ngalaba com, na www bụ subdomain nke example.com. Osisi a nke nkewa nwere ike inwe ihe ruru 127 ọkwa. Akara nwere ike ịnwe site na efu ruo mkpụrụedemede 63. A na-echekwa akara efu, nke ogologo efu, maka mpaghara mgbọrọgwụ. Aha ngalaba zuru ezu agaghị agafe ogologo nke mkpụrụedemede 253 na nnọchite anya ederede ya. N'ime ngosipụta ọnụọgụ abụọ nke DNS ogologo kachasị chọrọ 255 octets nke nchekwa, ebe ọ na-echekwa ogologo nke aha ahụ. Ọ bụ ezie na enweghị mmachi teknụzụ iji jiri akara ọ bụla na akara aha ngalaba nke nwere ike ịnọchite anya site na octet, aha nnabata na-eji usoro kachasị mma na akara akara. Ihe odide ndị a na-ekwe na akara bụ akụkụ nke akara ASCII, nke nwere mkpụrụedemede a ruo z, A ruo Z, ọnụọgụ 0 ruo 9, na hyphen. A maara iwu a dị ka iwu LDH (ederede, ọnụọgụ, hyphen). A na-akọwa aha ngalaba n'ụzọ na-enweghị atụ. Akara mmado nwere ike ghara ịmalite ma ọ bụ kwụsị na hyphen. Iwu ọzọ na-achọ na aha ngalaba ọkwa kachasị elu ekwesịghị ịbụ ọnụọgụgụ niile. Ntọala akara ASCII na-ekwe na DNS gbochiri nnọchite aha na okwu nke ọtụtụ asụsụ na mkpụrụedemede ma ọ bụ edemede ha. Iji mee ka nke a kwe omume, ICANN kwadoro Internationalizing Domain Names in Applications (IDNA) usoro, site na nke ngwa ndị ọrụ, dị ka ihe nchọgharị weebụ, eserese usoro Unicode n'ime akara ngosi DNS ziri ezi site na iji Punycode. N'afọ 2009 ICANN kwadoro ntinye nke ngalaba aha mba ụwa nke mba ụwa (ccTLDs). Na mgbakwunye, ọtụtụ ndekọ nke ngalaba aha dị elu (TLDs) ejirila usoro IDNA, na-eduzi RFC 5890, RFC 5891, RFC 5892, RFC 5893.  Ajụjụ: Gịnị bụ kacha nke osisi subdivision etoju?
127 ihe