NAPTR stands for Naming Authority Pointer and is a newer type of DNS record that supports regular expression based rewriting. Several NAPTR records can be chained together creating fairly sophisticated URI rewriting rules. A record can go through any number of rewrites before reaching a terminal condition. For example, after translating the phone number +1-770-555-1212 into the URI 2.1.2.1.5.5.5.0.7.7.1.e164.arpa as described by E.164, DDDS is used to transform it using rewrite rules gathered fr… (More on Naptr)