Network Working Group J. Abley
Internet-Draft ICANN
Updates: 3172 (if approved) O. Gudmundsson
Intended status: BCP Shinkuro Inc.
Expires: July 22, 2010 January 18, 2010
The Eternal Non-Existence of SINK.ARPA (and other stories)
draft-jabley-sink-arpa-03
Abstract
This document specifies a fully-qualified domain name in the Domain
Name System (DNS) that can be relied upon never to exist. The
availability of a name in the DNS which is guaranteed not to exist
has useful operational applications.
This document also provides a procedural framework for other names
that have special characteristics to be reserved, and for those
special characteristics to be codified as modifications to the normal
ARPA administration process.
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
This Internet-Draft will expire on July 22, 2010.
Copyright Notice
Copyright (c) 2010 IETF Trust and the persons identified as the
Abley & Gudmundsson Expires July 22, 2010 [Page 1]
Internet-Draft The Eternal Non-Existence of SINK.ARPA January 2010
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the BSD License.
Abley & Gudmundsson Expires July 22, 2010 [Page 2]
Internet-Draft The Eternal Non-Existence of SINK.ARPA January 2010
1. Introduction
The Domain Name System (DNS) is described in [RFC1034] and [RFC1035].
This document has three purposes:
1. to create a new IANA registry called "ARPA Reserved Names" (see
Section 4);
2. to define the special considerations of a single name SINK.ARPA,
a name which is defined never to exist (see Section 2);
3. to allow the procedures by which the ARPA zone is maintained, as
documented in [RFC3172], to be modified for names present in the
ARPA Reserved Names registry according to the special
characteristics of those names (see Section 5).
Abley & Gudmundsson Expires July 22, 2010 [Page 3]
Internet-Draft The Eternal Non-Existence of SINK.ARPA January 2010
2. SINK.ARPA
The special considerations for the name SINK.ARPA are that the name
SINK.ARPA shall be guaranteed never to have any resource records
associated with it. That is, the domain does not exist and queries
for it will result in name errors (NXDOMAIN). The reliable non-
existence of a globally-consistent and formally-defined name has some
operational utility (see Section 3 for examples).
Various top-level domains are reserved by [RFC2606], including
"INVALID". The use of "INVALID" as a codified, non-existent domain
was considered. However:
o INVALID is poorly characterised from a DNS perspective in
[RFC2606]; that is, the specification that INVALID does not exist
as a Top Level Domain (TLD) is imprecise given the various uses of
the term TLD in policy forums;
o the contents of the root zone are derived by interaction with many
inter-related policy-making bodies, whereas the administrative and
technical processes relating to the ARPA zone are much more
clearly defined in an IETF context;
o the use of ARPA for purposes of operational infrastructure (and,
by inference, the explicit non-use of a particular name in ARPA)
is consistent with the purpose of that zone, as described in
[RFC3172].
This document specifies that any request which would cause the name
SINK.ARPA to exist in the DNS should be denied.
Note that this document specifically does not recommend that the DNS
name "SINK.ARPA" be treated differently from any other DNS name,
operationally or in software.
Abley & Gudmundsson Expires July 22, 2010 [Page 4]
Internet-Draft The Eternal Non-Existence of SINK.ARPA January 2010
3. Examples
It is expected that the guaranteed non-existence of SINK.ARPA has
many general operational applications. What follows are two topical
examples at the time of writing. Note that these are speculative
applications of the non-existence of SINK.ARPA, and would require
more rigorous operational specification before they could be
recommended.
1. Mail Transfer Agents (MTAs) which deliver mail using the SMTP
protocol ([RFC5321]) look up MX records in order to identify the
host to which SMTP connection attempts should be made. For
devices which do not support SMTP, it may be desirable to prevent
MTAs from attempting any SMTP connection. Installing an MX
record whose RDATA includes SINK.ARPA in the EXCHANGE field
([RFC1034]) should cause compliant MTAs to make no connection:
SINK.ARPA does not exist, and A and AAAA records should not be
used when an MX record is present.
2. DNS UPDATE clients which send dynamic updates to DNS master
servers ([RFC2136]) identify the primary master server for a zone
using the MNAME field of the zone's SOA record ([RFC1034]). The
MNAME field is mandatory, but many zones intentionally do not
accept dynamic updates. DNS UPDATE messages for such zones may
constitute unwanted traffic, and can be suppressed by specifying
the MNAME to be SINK.ARPA.
Abley & Gudmundsson Expires July 22, 2010 [Page 5]
Internet-Draft The Eternal Non-Existence of SINK.ARPA January 2010
4. IANA Considerations
This document directs the IANA to create a registry as follows:
+-------------------------+----------------------------------------+
| Parameter | Value |
+-------------------------+----------------------------------------+
| Registry Name | ARPA Reserved Names |
| | |
| Reference | This document (RFCXXXX) Section 5 |
| | |
| Registration Procedures | IETF Standards Action and IAB approval |
+-------------------------+----------------------------------------+
The initial registry contents should be as follows:
+-----------+----------------------+---------+----------------------+
| Name | Purpose | RRTypes | Reference |
+-----------+----------------------+---------+----------------------+
| SINK.ARPA | Definitively | NONE | This document |
| | non-existent name | | (RFCXXXX) Section 2 |
+-----------+----------------------+---------+----------------------+
Abley & Gudmundsson Expires July 22, 2010 [Page 6]
Internet-Draft The Eternal Non-Existence of SINK.ARPA January 2010
5. Administration of the ARPA Domain
The management guidelines and operational requirements of the ARPA
domain is described in [RFC3172]. Requests to modify the ARPA zone
are specified in standards-track documents which, when approved by
the IESG and the IAB are sent to the IANA for implementation. This
document updates the procedures described in that document as
follows:
5.1. Criteria for "arpa" Sub-domains
Names which are included in the IANA registry "ARPA Reserved Names"
are reserved and require special consideration. The nature of that
special consideration is specified by reference within the ARPA
Reserved Names registry.
Abley & Gudmundsson Expires July 22, 2010 [Page 7]
Internet-Draft The Eternal Non-Existence of SINK.ARPA January 2010
6. IAB Considerations
IAB review and approval of this document is required, given the IAB's
technical and administrative function in the approval of changes to
the ARPA zone.
Abley & Gudmundsson Expires July 22, 2010 [Page 8]
Internet-Draft The Eternal Non-Existence of SINK.ARPA January 2010
7. Security Considerations
This document institutionalises a single name in the DNS to which
unwanted traffic can be directed. This name, SINK.ARPA, is specified
in this document not to exist in the DNS. If address records for
SINK.ARPA were to be introduced by exploiting insecurities in the
DNS, however, then those addresses would receive that unwanted
traffic. This might provide a leak of private information to a third
party, or have other unwelcome consequences.
The non-existence of SINK.ARPA will be cryptographically verifiable
when the ARPA zone is signed.
Abley & Gudmundsson Expires July 22, 2010 [Page 9]
Internet-Draft The Eternal Non-Existence of SINK.ARPA January 2010
8. References
8.1. Normative References
[RFC1034] Mockapetris, P., "Domain names - concepts and facilities",
STD 13, RFC 1034, November 1987.
[RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, November 1987.
[RFC2606] Eastlake, D. and A. Panitz, "Reserved Top Level DNS
Names", BCP 32, RFC 2606, June 1999.
[RFC3172] Huston, G., "Management Guidelines & Operational
Requirements for the Address and Routing Parameter Area
Domain ("arpa")", BCP 52, RFC 3172, September 2001.
8.2. Informative References
[RFC2136] Vixie, P., Thomson, S., Rekhter, Y., and J. Bound,
"Dynamic Updates in the Domain Name System (DNS UPDATE)",
RFC 2136, April 1997.
[RFC5321] Klensin, J., "Simple Mail Transfer Protocol", RFC 5321,
October 2008.
Abley & Gudmundsson Expires July 22, 2010 [Page 10]
Internet-Draft The Eternal Non-Existence of SINK.ARPA January 2010
Appendix A. Editorial Notes
This section (and sub-sections) to be removed prior to publication.
A.1. On the name SINK.ARPA
The name SINK.ARPA has been chosen as an editorial convenience:
having a name is more convenient than not having a name when
discussing the general proposal. No doubt other names would do the
job just as well.
A.2. Change History
00 Initial draft.
01 Updated following feedback from Alfred Hoenes.
02 Updated following feedback from Ralph Droms.
Abley & Gudmundsson Expires July 22, 2010 [Page 11]
Internet-Draft The Eternal Non-Existence of SINK.ARPA January 2010
Authors' Addresses
Joe Abley
ICANN
4676 Admiralty Way, Suite 330
Marina del Rey, CA 90292
USA
Phone: +1 310 301 3885
Email: joe.abley@icann.org
Olafur Gudmundsson
Shinkuro Inc.
4922 Fairmont Avenue, Suite 250
Bethesda, MD 20814
USA
Email: ogud@ogud.com
Abley & Gudmundsson Expires July 22, 2010 [Page 12]