RFC 3425 (rfc3425) - Page 1 of 5
Obsoleting IQUERY
Alternative Format: Original Text Document
Network Working Group D. Lawrence
Request for Comments: 3425 Nominum
Updates: 1035 November 2002
Category: Standards Track
Obsoleting IQUERY
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2002). All Rights Reserved.
Abstract
The IQUERY method of performing inverse DNS lookups, specified in RFC
1035, has not been generally implemented and has usually been
operationally disabled where it has been implemented. Both reflect a
general view in the community that the concept was unwise and that
the widely-used alternate approach of using pointer (PTR) queries and
reverse-mapping records is preferable. Consequently, this document
deprecates the IQUERY operation, declaring it entirely obsolete.
This document updates RFC 1035.
1 - Introduction
As specified in RFC 1035 (section 6.4), the IQUERY operation for DNS
queries is used to look up the name(s) which are associated with the
given value. The value being sought is provided in the query's
answer section and the response fills in the question section with
one or more 3-tuples of type, name and class.
As noted in [RFC 1035], section 6.4.3, inverse query processing can
put quite an arduous burden on a server. A server would need to
perform either an exhaustive search of its database or maintain a
separate database that is keyed by the values of the primary
database. Both of these approaches could strain system resource use,
particularly for servers that are authoritative for millions of
names.
Lawrence Standards Track