The authority, resolving and caching functions can all be present in a DNS server implementation, but this is not required: a DNS server can implement any one of these functions alone, without implementing the others.
Nadležnost, rešavanje i kreširanje funkcije mogu biti prisutni u implementaciji DNS servera, ali to nije neophodno: DNS server može sam da sprovede bilo koju od ovih funkcija, bez implementacije ostalih.