RFC 2915 (rfc2915) - Page 3 of 18

The Naming Authority Pointer (NAPTR) DNS Resource Record

RFC 2915                      NAPTR DNS RR                September 2000


   The final result is a RR that has several fields that interact in a
   non-trivial but implementable way.  This document specifies those
   fields and their values.

   This document does not define applications that utilizes this rewrite
   functionality. Instead it specifies just the mechanics of how it is
   done.  Why its done, what the rules concerning the inputs, and the
   types of rules used are reserved for other documents that fully
   specify a particular application.  This separation is due to several
   different applications all wanting to take advantage of the rewrite
   rule lookup process.  Each one has vastly different reasons for why
   and how it uses the service, thus requiring that the definition of
   the service be generic.

      The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL
      NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL"
      in this document are to be interpreted as described in RFC 2119.

      All references to Uniform Resource Identifiers in this document
      adhere to the 'absoluteURI' production of the "Collected ABNF"
      found in RFC 2396 [9].  Specifically, the semantics of URI
      References do not apply since the concept of a Base makes no sense
      here.

2. NAPTR RR Format

   The format of the NAPTR RR is given below.  The DNS type code [1] for
   NAPTR is 35.

   Domain TTL Class Type Order Preference Flags Service Regexp
   Replacement

   Domain
      The domain name to which this resource record refers.  This is the
      'key' for this entry in the rule database.  This value will either
      be the first well known key (.uri.arpa for example) or
      a new key that is the output of a replacement or regexp rewrite.
      Beyond this, it has the standard DNS requirements [1].

   TTL
      Standard DNS meaning [1].

   Class
      Standard DNS meaning [1].

   Type
      The Type Code [1] for NAPTR is 35.




Mealling & Daniel           Standards Track