Many sites connected to the Internet make use of IPv4 addresses that
are not globally-unique. Examples are the addresses designated in
RFC 1918 for private use within individual sites.
Devices in such environments may occasionally originate Domain Name
System (DNS) queries (so-called "reverse lookups") corresponding to
those private-use addresses. Since the addresses concerned have only
local significance, it is good practice for site administrators to
ensure that such queries are answered locally. However, it is not
uncommon for such queries to follow the normal delegation path in the
public DNS instead of being answered within the site.
It is not possible for public DNS servers to give useful answers to
such queries. In addition, due to the wide deployment of private-use
addresses and the continuing growth of the Internet, the volume of
such queries is large and growing. The AS112 project aims to provide
a distributed sink for such queries in order to reduce the load on
the corresponding authoritative servers. The AS112 project is named
after the Autonomous System Number (ASN) that was assigned to it.
RFC6304 described the steps required to install a new AS112 node, and
offered advice relating to such a node's operation. This document
updates that advice to facilitate the addition and removal of zones
for which query traffic will be sunk at AS112 nodes, using DNAME,
whilst still supporting direct delegations to AS112 name servers.
Working Group Summary
Since this document was an update of RFC 6304, the point was
raised that the Internet had changed some and that there were
better mechanisms to aid in these configurations. Specially
around IPv6 transport, and also to allow for using DNAME. The
outcome of this discussion was draft-ietf-dnsop-as112-dname-03.
Are there existing implementations of the protocol? Have a
The document updates an existing RFC that has gone through the
IETF RFC editorial process and is reflecting changing best
practices. Therefore existing implementations exist, and have
been observed for some time.
The Document Shepherd is Tim Wicinski.
The dnsop working group chairs are Tim Wicinski and Suzanne
The Area Director is Joel Jaggeli.