The Address Book Name Service Provider Interface (NSPI) Referral Protocol defines a remote procedure call (RPC) service that supplies a caller with the name of an NSPI server. Additionally, this protocol can return the Domain Name System (DNS)fully qualified domain name (FQDN) (1) of a mailbox server, given the distinguished name (DN) (1) of that server.
Sections 1.8, 2, and 3 of this specification are normative and can contain the terms MAY, SHOULD, MUST, MUST NOT, and SHOULD NOT as defined in [RFC2119]. Sections 1.5 and 1.9 are also normative but do not contain those terms. All other sections and examples in this specification are informative.