< draft-adpkja-dnsop-special-names-problem-02.txt   draft-adpkja-dnsop-special-names-problem-03.txt >
Network Working Group J. Abley Network Working Group G. Huston
Internet-Draft Dyn, Inc. Internet-Draft APNIC
Intended status: Informational P. Koch Intended status: Informational P. Koch
Expires: September 21, 2016 DENIC eG Expires: November 25, 2016 DENIC eG
A. Durand A. Durand
ICANN ICANN
W. Kumari W. Kumari
Google Google
March 20, 2016 May 24, 2016
Problem Statement for the Reservation of Top-Level Domains in the Problem Statement for the Reservation of Top-Level Domains in the
Special-Use Domain Names Registry Special-Use Domain Names Registry
draft-adpkja-dnsop-special-names-problem-02 draft-adpkja-dnsop-special-names-problem-03
Abstract Abstract
The dominant protocol for name resolution on the Internet is the The dominant protocol for name resolution on the Internet is the
Domain Name System (DNS). However, other protocols exist that are Domain Name System (DNS). However, other protocols exist that are
fundamentally different from the DNS, and may or may not share the fundamentally different from the DNS, and may or may not share the
same namespace. same namespace.
When an end-user triggers resolution of a name on a system which When an end-user triggers resolution of a name on a system that
supports multiple, different protocols (or resolution mechanisms) for supports multiple, different protocols (or resolution mechanisms), it
name resolution, it is desirable that the protocol used is is desirable that the protocol used is unambiguous, and that requests
unambiguous, and that requests intended for one protocol are not intended for one protocol are not inadvertently answered using
inadvertently answered using another. another.
RFC 6761 introduced a framework by which, under certain
circumstances, a particular domain name could be acknowledged as
being special. This framework has been used twice to reserve top-
level domains (.local and .onion) that should not be used within the
DNS, to avoid the possibility of namespace collisions in parallel use
of non-DNS name resolution protocols.
Various challenges have become apparent with this application of the RFC 6761 introduced a framework by which a particular domain name
guidance provided in RFC 6761. This document aims to document those could be acknowledged as being special. Various challenges have
challenges in the form of a problem statement, to facilitate further become apparent with this application of the guidance provided in RFC
discussion of potential solutions. 6761. This document aims to document those challenges in the form of
a problem statement in order to facilitate further discussion of
potential solutions.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 21, 2016. This Internet-Draft will expire on November 25, 2016.
Copyright Notice Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction: DNS, Name space or Name Spaces, Name Resolution
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . 2
3. RFC 6761 . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. IETF RFC6761 Special Names . . . . . . . . . . . . . . . . . 3
4. Architectural Considerations . . . . . . . . . . . . . . . . 6 3. Issues with 6761 . . . . . . . . . . . . . . . . . . . . . . 4
5. Technical Considerations . . . . . . . . . . . . . . . . . . 8 4. Candidate string evaluation and relationship with ICANN . . . 5
6. Organizational Considerations . . . . . . . . . . . . . . . . 9 5. Security Considerations . . . . . . . . . . . . . . . . . . . 6
6.1. External Organizational Considerations . . . . . . . . . 9 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6
6.2. IETF Internal Considerations . . . . . . . . . . . . . . 10 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 6
6.2.1. Process . . . . . . . . . . . . . . . . . . . . . . . 10 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 6
6.2.2. Technical Criteria . . . . . . . . . . . . . . . . . 11 8.1. Normative References . . . . . . . . . . . . . . . . . . 6
6.2.3. Name evaluation . . . . . . . . . . . . . . . . . . . 12 8.2. Informative References . . . . . . . . . . . . . . . . . 7
6.3. The ICANN process to evaluate names . . . . . . . . . . . 13 Appendix A. Editorial Notes . . . . . . . . . . . . . . . . . . 7
7. Security Considerations . . . . . . . . . . . . . . . . . . . 14 A.1. Venue . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 A.2. Change History . . . . . . . . . . . . . . . . . . . . . 7
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15 A.2.1. draft-adpkja-special-names-problem-00 . . . . . . . . 7
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 15 Appendix B. Change history . . . . . . . . . . . . . . . . . . . 7
10.1. Normative References . . . . . . . . . . . . . . . . . . 15 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8
10.2. Informative References . . . . . . . . . . . . . . . . . 15
Appendix A. Editorial Notes . . . . . . . . . . . . . . . . . . 16
A.1. Venue . . . . . . . . . . . . . . . . . . . . . . . . . . 17
A.2. Pithy Quotes from History . . . . . . . . . . . . . . . . 17
A.3. Change History . . . . . . . . . . . . . . . . . . . . . 17
A.3.1. draft-adpkja-special-names-problem-00 . . . . . . . . 17
Appendix B. Change history . . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18
1. Terminology
Clear and unambiguous use of terminology is important for the clear
formulation of any problem statement. The DNS protocol suffers from
imprecise and overloaded terminology (for example, see [RFC7719]).
The use of terms and concepts from other naming systems that are
similar (but different) simply confuses matters further.
In the interests of clarity, the following terms used in this
document are to be interpreted as follows:
Registry (n): the Special-Use Domain Names Registry created by
[RFC6761] and published at [IANA-SPECIAL-USE].
[This section to be completed following review and refinement of the
rest of the text.]
2. Introduction
Some systems use the last label in a name to act as a switch to a
different, non-DNS resolution process - examples of such switches
include: .local (to use mDNS) and .onion (to use Tor). This switch
practice is not explicitly documented anywhere, and the method for
accomplishing this varies by implementation. As an interesting
aside, the full semantics of domain names isn't really documented
anywhere either, although [I-D.lewis-domain-names] is a current
attempt to rectify this.
This technique of using the last label as a switch has a number of
properties which make it attractive to people implementing alternate
name resolution systems, including:
o The names can follow the common DNS syntax of LDH labels,
separated by dots. This means that these names can be entered in
any application which takes existing DNS names.
o The switch to the new resolution process can be implemented in a
number of ways, such as custom application code, a shim in the
normal DNS resolution process, or on the system's configured DNS
servers.
o The names "look" like names to users.
Note that [RFC6303] defines "locally served zones". The important
difference is that in [RFC6303], the names get registered for special
treatment if they are already special: they are not declared special
by the registration.
[RFC6761] defines ways to reserve domain names. This could be read
to augment the technical uses exemption made in [RFC2860] (also
called "the IETF-ICANN MoU"). [RFC2860] says:
"Note that (a) assignments of domain names for technical uses
(such as domain names for inverse DNS lookup), (b) assignments of
specialized address blocks (such as multicast or anycast blocks),
and (c) experimental assignments are not considered to be policy
issues, and shall remain subject to the provisions of this
Section 4."
The framework in [RFC6761] has recently been used to reserve the
.onion label, allowing it to be used as a switch to the Tor
resolution process, as described in [RFC7686]. Because the .onion
label in the IANA "Special-Use Domain Names" registry
[IANA-SPECIAL-USE], the Tor Project can be assured that there will
not be a .onion TLD created in the IANA rooted DNS, and thus the
possibility of collisions in the namespace will be avoided.
The discussions in the DNSOP Working Group (WG) and the IETF Last
Call processes for the .onion registration in the Special Use Domain
Names registry (1,200 messages) have made it apparent that clarity
about if and how to treat this "protocol switching" practice would
help a lot in deciding the merit of future similar applications.
One possible outcome of the discussion would be to decline to
recognize such usage of domain names in the architecture; another
possible outcome is to formalize it and better understand the issues
that come with it.
An additional consideration is that names which follow the DNS syntax
(including those which use alternate name resolutions processes to
the DNS) are in the same namespace as names in the DNS. This means
that currently both the IETF (through [RFC6761]) and ICANN are making
allocations or reservations from a shared namespace. If this
continues to be the case, in order to avoid conflict, close
coordination between the two organizations is necessary.
3. RFC 6761
Section 5 of [RFC6761] describes seven questions to be answered to
justify how and why a particular domain name is special. These seven
questions can be broadly categorized as follows:
1. impact on end-users;
2. impact on applications;
3. impact on name resolution APIs and libraries;
4. impact on recursive resolvers;
5. impact on authoritative DNS servers;
6. impact on DNS server operators;
7. impact on DNS registries and registrars.
The intent of those seven questions was originally to serve as the
justifications for why a proposed special-use registration should be
granted, demonstrating that it (a) provides a result that the
community judges to be good, and (b) the aforementioned good result
cannot reasonably be achieved in another way. The rough consensus
from significant discussion was that .onion did satisfy both (a) and
(b), but this was not clearly demonstrated by the answers to the
"seven questions". Furthermore, it is unclear if and how these
questions could reliably and unambiguously be used to make the
determination, leading to the conclusion that they are generally
inadequate for making the determination whether a particular domain
name qualifies as requiring special/different treatment.
Applications which follow the [RFC6761] process are likely to devolve
into a "beauty contest". Moreover, the answers to the seven
questions are not available in a machine readable form to
applications that want to follow [RFC6761].
So the answers to these seven questions can better be seen as
providing guidance to the corresponding seven audiences on how to
handle a special-use domain name once it has been reserved by
inclusion in the Registry, and not as entrance filters for inclusion
in the registry.
The answers to the seven questions specify desired behavior in the
internet for handling a particular domain name, not the basis for
deciding whether the effort to implement special behavior across all
of those audiences is worth the cost. This indifference to costs is
not necessarily scalable for making future decisions about potential
inclusion in the registry.
The justification in [RFC6761] is concerned with the rationale of
reserving a domain name that precludes its subsequent use as a top
level domain name. However, the document fails to offer such a
rationale, and instead requires the justification of the reserved
name to include the provision of guidance to a number of audiences
(users, application developers, DNS resolver applications, DNS
resolution service operators, and name registries and registrars) as
to how to handle names that are listed in this registry. But this
guidance is not, in and of itself, an adequate rationale for the
selection of a particular name value to be reserved in this registry.
What is missing in [RFC6761] is the consideration of the name itself.
If one were to contrast the procedures relating to the admission of a
name to the IETF Special Use Name registry to the processes
associated with the New gTLD Program operated by ICANN [NEW-GTLD],
then it is evident that the IETF process does not admit many
considerations which appear to be areas of evaluation in the New gTLD
program. More on this in section Section 6.3.
This document proposes to categorize considerations related to the
usage of the [RFC6761] registry for protocol switches in 3
categories: Architectural, Technical and Organizational. This
document then lists a number of questions to drive the discussion.
The list of issues discussed here is non-exhaustive.
However, some people have noted that [RFC6761] describes other
alternative special handling aside from protocol switches. That
alternative special handling must be considered carefully at the time
of publication of the defining RFC, regardless of the nature of the
special use.
4. Architectural Considerations
The first thing to consider in this discussion is that not all names
(or domain names) are part of the Domain Name System. See
[I-D.lewis-domain-names] for an in-depth discussion on this topic.
At the time of writing, two top-level domain names reserved by
inclusion in the Registry went through the [RFC6761] process and are
used by name resolution protocols other than the DNS:
.local is used by the Multicast DNS protocol specified in
[RFC6762] which is similar in some respects to the DNS, but which
uses a different well-known port number and is limited to a
particular multicast scope;
.onion is used to construct names that designate services
reachable via the Tor network using onion routing.
These two name resolution protocols are, to varying degrees,
different from the DNS, and the namespaces used in each naming scheme
are also different. The top-level label is effectively being used as
a name resolution protocol identifier. At the core of the issue is
that different "strings" that look like "domain names" (i.e. are
within the same name space) but are not DNS names are used
interchangeably in the URI (or URN).
In particular, DNS imposes constraints on name syntax. An example of
such constraints is the 63 octet limit per label. Strings used in
the .onion domain do not have that constraint.
It could be argued that in the absence of a more elegant alternative,
a pragmatic choice to embed protocol selectors as namespace tokens
has effectively already been made. The running code and effective
consensus in how it should be used by significant user bases should
not be discounted. Although the reservation of names in the DNS
namespace can be made at any level, the two examples above
demonstrate use-cases for reservation at the top-level, and hence
that case must be considered.
The underlying discussion here is the tussle between the applications
and the network. Application architects see using special name tags
(such as .onion) as an easy way to get new features deployed. They
consider the hurdles of deploying new URI schemes such as
http:/onion/onion-name as too onerous and too slow to deploy for
their needs. Network architects worry of overloading the semantics
of DNS names and/or creating a name space that is larger than the DNS
namespace. They refer to bad precedents such as .uucp and .bitnet.
The fundamental point to consider here is the unicity (or
multiplicity) of the name space. Are we talking about one namespace
with different resolution protocols or independent name spaces?
It might it be helpful to point out that the property of interest
here is the assurance of uniqueness of a name, and another way of
thinking about the question is whether it applies across domain names
as people expect or need it to? None of this would matter if people
didn't expect names constructed according to whatever rules they're
following to be unique across a set of names that spans multiple
operating environments and resolution protocols.
In [RFC2826] the IAB noted that
"To remain a global network, the Internet requires the existence
of a globally unique public name space. The DNS name space is a
hierarchical name space derived from a single, globally unique
root."
"Maintaining a globally-unique public namespace that supports
different name resolution protocols is hence an architectural
requirement, and some facility for reservation of top-level
domains in the DNS is necessary."
If we were to accept the notion that the last label of a domain name
is actually a protocol switch, we are actually building a catalog of
all top level domains and what resolution protocol each one invokes.
Note that such a catalog does not formally exist today, because
[RFC6761] is an exception list to the general case which is supposed
to use regular DNS as resolution protocol. Such a catalog may remain
a concept to guide this discussion or be implemented as an actual
IANA registry [IANA-SPECIAL-USE]. In effect, it would associate TLDs
with indications on how applications and resolvers should treat them.
However, such an approach would leave open the question of not-yet-
defined TLDs. No resolution mechanism could be associated with those
in advance so that systems would have to continue to assume that such
names are part of the DNS. For reasons of completeness it is noted
that suggestions have been made to help the distinction by using
special labels (as in IDNs).
It should also be noted that there are choices for a protocol switch
other than reserving labels. In particular, a proposal to move those
protocol switches under a specific top level domain has been
discussed (.ALT). If that architecture choice is made, some of the
questions listed in the sections below would become moot.
Note: [RFC6761] mentions the reserved names could be any label in a
domain name, not just the rightmost one (or ones). However, this
creates a number of complications and has not seen much support in
the community as of now.
5. Technical Considerations
Each of the seven questions posed by [RFC6761] has the potential to
describe why it may be necessary for special handling of the
requested name(s) in applications by a particular audience. However,
aside from reserving the name, it is not entirely clear what any of
those audiences might further expect as a result of a successful
request to add a top-level domain to the Registry.
For example, reservation of a top-level domain by the IETF does not
guarantee that DNS queries for names within a reserved domain will
not be sent over the Internet. The requirements of the operators of
recursive resolvers in the DNS cannot be relied upon to be
implemented; the impact on the operators of DNS authoritative servers
hence cannot be reliably assumed to be zero. In the case of
[RFC7686], leakage of .onion queries on the Internet might lead to
disclosure of private information that, in some cases, might pose a
risk to the personal safety of end-users.
At the time of writing, the [RFC6761] registry does not include
direct guidance for any of the seven audiences, relying instead upon
a reference for each entry in the Registry to the document that
requested its insertion. Such documents might well be opaque to many
readers; [RFC6762] is a seventy-page protocol specification, for
example, which is arguably not the most effective way to set
expectations of non-technical end-users).
Useful reservations of top-level domains should be accompanied by
documentation of realistic expectations of each of the seven
audiences, and the evaluation of particular requests should consider
the practical likelihood of those expectations being met and the
implications if they are not.
Here is a non-exhaustive list of additional questions that have
surfaced in discussion of requests for names to be added to the
Special Use Names registry:
What does it mean to have a "non-DNS" entry in the registry
described above?
Are applications supposed to check that registry to know what to
do?
Can, or should, applications do this check dynamically?
What if an application makes this dynamic check and discovers the
name contains a switch it does not know how to handle?
Similar questions applies to resolvers (DNS and non-DNS); what is the
expected behavior?
One particular avenue of investigation would be to see if such
considerations could be encoded in machine understandable code in an
extension of the current [RFC6761] registry.
6. Organizational Considerations
This section gives two categories of organizational considerations:
external and internal.
6.1. External Organizational Considerations
The policy surrounding the implementation and management of top-level
domains in the DNS has been developed using a multi-stakeholder
process convened by ICANN according to the MoU between ICANN and IETF
[RFC2860]. It is out of scope for this document to revisit that MoU.
While discussing the particular attributes that make a domain name
special, [RFC6761] notes that "the act of defining such a special
name creates a higher-level protocol rule, above ICANN's management
of allocatable names on the public Internet."
[RFC2860] draws a line between what is policy and what is technical.
A variety of opinions have been expressed regarding whether [RFC6761]
blurs this line. In particular, [HUSTON] has one viewpoint on the
topic. As noted earlier, it is out of scope for this document to
analyse this issue beyond noting that such a variety of views exist.
Taking a different perspective, it has been argued that [RFC6761]
specifically extends the DNS protocol to include special treatment
for names in the registry, and that there's nothing in [RFC2860] at
all that limits the IETF's authority to change the protocol.
However, it should be noted that, if the IETF were to formalize the
concept of protocol/name switch in the Internet architecture,
coordination would be require between ICANN and IETF on such names.
Using the analogy described above of a catalog/registry of such
switches, care must be taken to make sure we do not end up with two
process streams allowed to create entries without complete
synchronization.
6.2. IETF Internal Considerations
6.2.1. Process
[RFC6761] specifies the way in which "an IETF 'Standards Action' or
'IESG Approval' document" should present answers to the questions
described above (see Section 2), but does not describe the process by
which the answers to those questions should be evaluated.
For example, it is not clear who is responsible for carrying out an
evaluation. A document which requests additions to the Registry
might be performed by the IESG, by the IAB, by the DNSOP WG, by an
ad-hoc working group, by expert review or any combination of those
approaches. [RFC6761] provides no direction.
As an illustration of the inconsistency that has been observed
already, [RFC6762] was published as an AD-sponsored individual
submission in the INT area, and the IESG evaluation record does not
reveal any discussion of the reservation of the .local top-level
domain in the DNS. [RFC7686], however, was published as a working
group document through the DNSOP WG, and an extensive discussion by
both the participants of the DNSOP WG and the IESG on the merits of
the request took place. The evaluation process, in the absence of
clear direction, is demonstrably inconsistent.
We should point to [RFC5226] and explicitly quote the definition of
"Standards Action" or "IESG Approval":
IESG Approval is not intended to be used often or as a "common
case"; indeed, it has seldom been used in practice during the
period RFC 2434 was in effect. Rather, it is intended to be
available in conjunction with other policies as a fall-back
mechanism in the case where one of the other allowable approval
mechanisms cannot be employed in a timely fashion or for some
other compelling reason. IESG Approval is not intended to
circumvent the public review processes implied by other policies
that could have been employed for a particular assignment. IESG
Approval would be appropriate, however, in cases where expediency
is desired and there is strong consensus for making the assignment
(e.g., WG consensus).
So, while it is very interesting to note that [RFC6761] was an AD
sponsored individual submission in spite of two active DNS related
WGs, [RFC6762] is probably clean: it defines the protocol and is
itself on standards track.
[RFC7686] however, while on standards track, does not define the TOR
protocol, so it was used to fulfill the 'standards action'
requirement by the letter. It contains normative references to non-
IETF protocols, which is noteworthy.
A comparison of the two "seven question forms" from [RFC6761] reveals
that at least the responses to questions 2, 3, and 4, differ
significantly while there is no defined way to communicate the
difference to the affected software entities.
An alternate view has been expressed with regard to the protocol 1. Introduction: DNS, Name space or Name Spaces, Name Resolution
evaluation. It states that the authority belongs to the IESG to seek Protocols
whatever support it likes, within the established process, in making
standards decisions, including delegating evaluation of a specific
registry change proposal to a WG or a directorate. The IESG might
have varied what guidance it sought, but that does not constitute
"inconsistency" under the process. That being said, more complete
evaluation guidance would be helpful to the IESG and the community.
6.2.2. Technical Criteria For a very long time, DNS and the name space have been perceived as
one and the same. However, this has not always been the case; in the
past, other name resolution protocols were popular. One can remember
NIS, NIS+, host files, UUCP addresses... Most of those have been
obsoleted by the DNS in the late 1990s. More information on the
history of names and namespaces can be found in
[I-D.lewis-domain-names].
Regardless of the actual name being proposed as protocol and/or More recently, new name resolution protocols have been proposed, each
namespace switch, it is also not clear what technical criteria the addressing a particular need or a particular community. For example,
evaluation body should use to examine the merit of an application for the DONA handle system has been used by the publication industry.
such a reserved name/protocol switch. For example, is large scale The Apple "Bonjour" set of protocols, inspired by what was available
prior deployment an acceptable criteria? A number of people have on Appletalk networks, has been developed to perform automatic name
clearly answered "no" to that question as it would only encourage resolution on a local IP network. The TOR project is using the onion
"squatting" on names. system to obfuscate communications, the GNU Name System (GNS) system
is using block chains to build a decentralized name system to offer
"privacy and censorship resistance". Many more have been proposed.
However, in the case of .local and .onion, those particular domain Those alternate name resolution protocols do not exist in a vacuum.
names were already in use by a substantial population of end-users at Application developers have expressed a strong desire to build their
the time they were requested to be added to the Registry. Rightly or software so it will function in any of those universes with minimal
not, the practical cost of a transition away from the requested changes. Doing so means that the software has to recognize
strings was argued as a justification for their inclusion in the deterministically what kind of name it is dealing with and associate
registry. it with the corresponding name resolution protocol. Because of this
desired lack of explicit signaling, an algorithmic solution
frequently chosen by application developers consists simply to use a
special tag padded at the end of a name to indicate an alternate name
resolution method. Examples: if a name ends in .local, the software
uses the Apple Bonjour protocol based on multicast DNS; if the name
ends in .onion, it uses the TOR protocol; if the name ends in .gnu,
it uses the GNS protocol, etc... One noteworthy exception to this
approach is the DONA system that exists independently and has
developed its own interoperability solution with the DNS.
6.2.3. Name evaluation A result of the above is that a number of applications have been
developed (and massively distributed) that have encoded their
favorite "tag" as a DNS TLD in a free-for-all, beginning their
existence squatting on that DNS space... .local, .gnu, .onion
started out like that.
With regard to the actual choice of name, [RFC6761] is silent. The 2. IETF RFC6761 Special Names
answers to the seven questions are expected to tell how a name,
presumably already chosen outside of the process, might be handled if
it is determined to be a "special use" name. However, it is silent
on how to choose a name or how to evaluate a specific proposed name.
Going back to the IETF process used for the evaluation of .local and The IETF used a provision from the IETF/ICANN MoU [RFC2860] section
.onion, one might ask the following questions: 4.3 that says that "(a) assignments of domain names for technical
uses" is to be considered the purview of IETF (as in, outside of the
scope of ICANN) in order to create a way to reserve such names in a
list of "special names". That process is documented in [RFC6761]
(which curiously does not directly refer the IETF/ICANN MoU). It was
first applied for .local and more recently for .onion. When that
process was put in place, it was thought it would only be used a
handful of times. However, a large number of applications have since
been made to the IETF. The .onion evaluation took almost a year and
has started a massive (and often heated) discussion in the IETF.
For example, what consideration have there been in the This [RFC6761] process to reserve special name has a number of
intellectual property rights in the reservation of a name in this issues, that can be grouped in two categories:
Special Use Name registry, and what procedures should be followed
in the case of a dispute over the rights to use a name in this
manner? Also, to what extent could such a reservation of a name
in this Special Use Names registry be used to block competing
interests and/or competing technologies? What are the competition
and consumer issues that need to be considered if the reservation
of a name in this registry causes some form of exclusive access
and reduced competitive access, or where there is no ability for
consumers to exercise choice in a situation where providers
compete in the offering of services?
A related consideration is that the current process of admission o Issues with [RFC6761] itself, including issues discovered during
to the Special Use Name registry appears to admit no formal the evaluation of .onion
assessment of environmental impact. Is the name that is proposed
to be entered into this registry already being used in local
contexts, with or without an association with DNS name resolution,
such that its use as a reserved name through an entry in this
registry, and its continued use in local contexts could cause harm
to users? To what extent can this impact be assessed, and what
level of impact is considered acceptable?
While the "seven questions" relate to altered behaviors by o Higher level issues regarding candidate string evaluation and
specific audiences and users of names there is no explicit relationship with ICANN
consideration of the security in this process. Is the
registration of such a name a "safe" action for the IETF to take?
To what extent could the use of this reserved name be used in a
hostile or malicious manner? What measures have been taken to
mitigate or otherwise address such potential vulnerabilities?
ICANN has created an entire set of groups, organizations, committees, 3. Issues with 6761
processes and procedures to deal with the evaluation of applied for
new TLDs, complete with a cadre of lawyers and policy people. Unless
the IETF were willing to do the same, it would have a hard time
performing evaluation of the strings themselves, distinct from the
evaluation of the technology behind the name resolution system.
An alternate view has been expressed that such a process is not 1. It can be use to reserve any names, not just TLDs. For example,
necessary because the IESG is the body that makes the decision on a it could potentially be used to forbid a registrar to register
specific name reserved by [RFC6761], and the IETF has a workable specific names in any TLD.
appeal process to deal with any potential issues. However, looking
at the level of contention created in the ICANN process around the
choice of certain names, serious doubts have been expressed to the
scalability and ultimate viability of such an appeal process.
6.3. The ICANN process to evaluate names 2. [RFC6761] does not mention if the protocol for which it is
requested to reserve a string should be published as an RFC
document. Most applications have, so far, come from outside
organizations, and the described protocols that have not been
developed by the IETF.
Section 4.3 of [RFC2860] says: 3. [RFC6761] does not provide clear enough direction as to what
party is responsible for carrying out the evaluation.
Two particular assigned spaces present policy issues in addition 4. There are ambiguities and no formal criteria on how the IETF can
to the technical considerations specified by the IETF: the (or even whether the IETF should) evaluate the merits of
assignment of domain names, and the assignment of IP address applicants to [RFC6761] reservations. Section 5 of [RFC6761]
blocks. describes seven questions to be answered by an applicant for
[RFC6761] status. However, running this process for the .onion
application showed that those seven questions are inadequate for
making the determination for whether a particular strings
qualifies as requiring special/different treatment.
This remains as true today as when it was written (2000). Domain 5. Placing a string in the [RFC6761] registry does not guarantee
names have a number of considerations that have complex policy issues that DNS queries for names within a reserved domain will not be
that ICANN deals with and which the IETF may not be well equipped to sent over the Internet. As such, the applicant for [RFC6761]
handle. status cannot be guaranteed that leakage will not occur and will
need to take this into account in the protocol design. Useful
reservations of top-level domains should be accompanied by
documentation of realistic expectations of each of the seven
audiences, and the evaluation of particular requests should
consider the practical likelihood of those expectations being met
and the implications if they are not.
The ICANN process applicant have to go through to get a name is 6. The [RFC6761] registry lists the reserved names but does not
described in the applicant guide book [GUIDEBOOK], which is a 338 include direct guidance, neither in free text form nor in machine
page document. It should however be noted that the current round of readable instructions, for any of the seven audiences, relying
gTLD application is closed and rules may differ in the next round if instead upon a reference for each entry in the Registry to the
and when it happens. document that requested its insertion. Such documents might well
be opaque to many readers; [RFC6762] is a seventy-page protocol
specification, for example, which is arguably not the most
effective way to set expectations of non-technical end-users
Considerations include, but are not limited to: 4. Candidate string evaluation and relationship with ICANN
Geographical During the most recent round of new gTLD applications, 1. IETF does not have process to evaluate the proposed strings
there were a number of applications for so call "geographic" candidate to [RFC6761] status for things like trademark, IPR,
terms. These included applications for .amazon and .patagonia. name collision, etc.. Instead, the IETF relies on document
The .amazon application in particular was controversial - the reviews, working group and IETF-wide last call, and ultimately a
governments of Brazil and Peru requested that ICANN's Governmental decision is made by the IESG. That decision can be appealed,
Advisory Committee (GAC) to issue a warning that granting .amazon first to the IAB and second to the ISOC board of trusties.
to Amazon would "prevent the use of this domain for purposes of
public interest related to the protection, promotion, and
awareness raising on issues related to the Amazon biome." The
IETF is not well suited to evaluating this sort of issue.
Brands / Trademark law If Wile E. Coyote approached the IETF 2. The IETF "review" process is not foolproof. [RFC7788] describing
requesting that the IETF reserve .acme, a trademark held by a the "home networking control protocol" was recently published.
large corporation making anvils and giant slingshots, the IETF That document includes text instructing devices to use names
could become embroiled in trademark lawsuit - and even if the IETF terminating by default with the .home suffix. [RFC7788] did not
were not, we have enough armchair lawyers that the discussions reference [RFC6761] anywhere and had no IANA sections about this
would be extremely annoying :-). Closely related to this issue is reservation. It was published without anyone noticing this
"protected designation of origin (PDO)" - for example, Champagne. during the entire review process. The issue was caught after the
publication, and an errata was published.
String similarity ICANN has an entire process for evaluating the 3. There exists now at least 2 streams to take strings out of the
string similarity / confusability between applied for (and global namespace: IETF RFC6761 "special names" and ICANN "gTLD
current) strings - for example, under what conditions would the program" (see [NEW-GTLD]). It is important to observed that the
IETF be able to make a determination if someone attempted to use IETF RFC6761 reservations could happen in a ad-hoc fashion at any
[RFC6761] to reserve .c0m? time, while ICANN delegations typically happen in batches, and
the latest gTLD round is closed. Note: the ICANN gTLD
application process is described in the applicant guide book
[GUIDEBOOK].
International Organization Names Certain names and organizations get 4. The major risk is having a conflict when both the IETF and ICANN
additional protection under trademark law - well known examples of want to use the same or similar strings. There exist no defined
this are the RedCross/RedCrescent and the International Olympic cooperation between ICANN and IETF to avoid this problem.
Committee (IOC). Whether or not this should be the case is well
outside anything that the IETF should have an opinion on but,
undoubtedly, there are many within the community who will have an
opinion (and will want to argue it at length).
Offensive Terms There are a huge range of these, from the obscure / 5. There might be limited concerns if IETF were to reserve a string
archaic (waesucks, gadsbudlikins) to the more obvious and current. outside of an ICANN gTLD round. The next ICANN gTLD applicant
Certain terms are sufficiently offensive that the IETF would have book would simply refer to the existing list at publication time.
a hard time coming to any useful consensus (other then "Eeeew!") However, there is a possibility of conflict if an IETF
reservation were to happen during an ICANN gTLD round. A
hypothetical case study could be somebody trying a denial of
service attack early in the ICANN application process by asking
the IETF to reserved a string sought after by a competitor.
7. Security Considerations 5. Security Considerations
This document aims to provide a problem statement that will inform This document aims to provide a problem statement that will inform
future work. While security and privacy are fundamental future work. While security and privacy are fundamental
considerations, this document expects that future work will include considerations, this document expects that future work will include
such analysis, and hence no attempt is made to do so here. See among such analysis, and hence no attempt is made to do so here. See among
other places [SAC-057] other places [SAC-057]
Reserving names has been presented as a way to prevent leakage into Reserving names has been presented as a way to prevent leakage into
the DNS. However, instructing resolvers to not forward the queries the DNS. However, instructing resolvers to not forward the queries
(and/or by instructing authoritative servers not to respond) is not a (and/or by instructing authoritative servers not to respond) is not a
guarantee that such leakage will be prevented. The security (or guarantee that such leakage will be prevented. The security (or
privacy) of an application MUST NOT rely on names not being exposed privacy) of an application MUST NOT rely on names not being exposed
to the Internet DNS resolution system. to the Internet DNS resolution system.
8. IANA Considerations 6. IANA Considerations
This document has no IANA actions. This document has no IANA actions.
9. Acknowledgements 7. Acknowledgements
Thanks to Paul Hoffman for a large amount of editing. Thanks to Paul Hoffman for a large amount of editing.
10. References 8. References
10.1. Normative References 8.1. Normative References
[IANA-SPECIAL-USE] [IANA-SPECIAL-USE]
IANA, "Special-Use Domain Names", 2016, IANA, "Special-Use Domain Names", 2016,
<https://www.iana.org/assignments/special-use-domain- <https://www.iana.org/assignments/special-use-domain-
names>. names>.
[RFC1034] Mockapetris, P., "Domain names - concepts and facilities",
STD 13, RFC 1034, DOI 10.17487/RFC1034, November 1987,
<http://www.rfc-editor.org/info/rfc1034>.
[RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, DOI 10.17487/RFC1035,
November 1987, <http://www.rfc-editor.org/info/rfc1035>.
[RFC2860] Carpenter, B., Baker, F., and M. Roberts, "Memorandum of [RFC2860] Carpenter, B., Baker, F., and M. Roberts, "Memorandum of
Understanding Concerning the Technical Work of the Understanding Concerning the Technical Work of the
Internet Assigned Numbers Authority", RFC 2860, Internet Assigned Numbers Authority", RFC 2860,
DOI 10.17487/RFC2860, June 2000, DOI 10.17487/RFC2860, June 2000,
<http://www.rfc-editor.org/info/rfc2860>. <http://www.rfc-editor.org/info/rfc2860>.
[RFC6761] Cheshire, S. and M. Krochmal, "Special-Use Domain Names", [RFC6761] Cheshire, S. and M. Krochmal, "Special-Use Domain Names",
RFC 6761, DOI 10.17487/RFC6761, February 2013, RFC 6761, DOI 10.17487/RFC6761, February 2013,
<http://www.rfc-editor.org/info/rfc6761>. <http://www.rfc-editor.org/info/rfc6761>.
[RFC6762] Cheshire, S. and M. Krochmal, "Multicast DNS", RFC 6762, [RFC6762] Cheshire, S. and M. Krochmal, "Multicast DNS", RFC 6762,
DOI 10.17487/RFC6762, February 2013, DOI 10.17487/RFC6762, February 2013,
<http://www.rfc-editor.org/info/rfc6762>. <http://www.rfc-editor.org/info/rfc6762>.
[RFC7686] Appelbaum, J. and A. Muffett, "The ".onion" Special-Use [RFC7788] Stenberg, M., Barth, S., and P. Pfister, "Home Networking
Domain Name", RFC 7686, DOI 10.17487/RFC7686, October Control Protocol", RFC 7788, DOI 10.17487/RFC7788, April
2015, <http://www.rfc-editor.org/info/rfc7686>. 2016, <http://www.rfc-editor.org/info/rfc7788>.
10.2. Informative References 8.2. Informative References
[GUIDEBOOK] [GUIDEBOOK]
ICANN, "gTLD Application Guidebook", June 2012, ICANN, "gTLD Application Guidebook", June 2012,
<https://newgtlds.icann.org/en/applicants/agb/guidebook- <https://newgtlds.icann.org/en/applicants/agb/guidebook-
full-04jun12-en.pdf>. full-04jun12-en.pdf>.
[HUSTON] Huston, G., "What's in a Name?", December 2015, [HUSTON] Huston, G., "What's in a Name?", December 2015,
<http://www.circleid.com/posts/20151222_whats_in_a_name/>. <http://www.circleid.com/posts/20151222_whats_in_a_name/>.
[I-D.lewis-domain-names] [I-D.lewis-domain-names]
Lewis, E., "Domain Names", draft-lewis-domain-names-02 Lewis, E., "Domain Names", draft-lewis-domain-names-02
(work in progress), January 2016. (work in progress), January 2016.
[NEW-GTLD] [NEW-GTLD]
ICANN, "New Generic Top-Level Domains", 2016, ICANN, "New Generic Top-Level Domains", 2016,
<https://newgtlds.icann.org/>. <https://newgtlds.icann.org/>.
[RFC1918] Rekhter, Y., Moskowitz, B., Karrenberg, D., de Groot, G.,
and E. Lear, "Address Allocation for Private Internets",
BCP 5, RFC 1918, DOI 10.17487/RFC1918, February 1996,
<http://www.rfc-editor.org/info/rfc1918>.
[RFC2826] Internet Architecture Board, "IAB Technical Comment on the
Unique DNS Root", RFC 2826, DOI 10.17487/RFC2826, May
2000, <http://www.rfc-editor.org/info/rfc2826>.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226,
DOI 10.17487/RFC5226, May 2008,
<http://www.rfc-editor.org/info/rfc5226>.
[RFC6303] Andrews, M., "Locally Served DNS Zones", BCP 163,
RFC 6303, DOI 10.17487/RFC6303, July 2011,
<http://www.rfc-editor.org/info/rfc6303>.
[RFC7719] Hoffman, P., Sullivan, A., and K. Fujiwara, "DNS
Terminology", RFC 7719, DOI 10.17487/RFC7719, December
2015, <http://www.rfc-editor.org/info/rfc7719>.
[SAC-057] ICANN Security and Stability Advisory Committee, "SSAC [SAC-057] ICANN Security and Stability Advisory Committee, "SSAC
Advisory on Internal Name Certificates", March 2013, Advisory on Internal Name Certificates", March 2013,
<https://www.icann.org/en/system/files/files/sac- <https://www.icann.org/en/system/files/files/sac-
057-en.pdf>. 057-en.pdf>.
Appendix A. Editorial Notes Appendix A. Editorial Notes
This section (and sub-sections) to be removed prior to publication. This section (and sub-sections) to be removed prior to publication.
A.1. Venue A.1. Venue
An appropriate forum for discussion of this draft is for now the An appropriate forum for discussion of this draft is for now the
DNSOP WG. DNSOP WG.
A.2. Pithy Quotes from History A.2. Change History
The question has arisen as to how the toplevel naming authority
decides who gets a toplevel name and who must get by with a non-
toplevel name. The suggestion was made by MOCKAPETRIS@USC-ISIF
that perhaps the existing toplevel nameholders might vote on
whether the applicant for a new toplevel name should be granted,
with a majority needed for approval. It seems to me this might
produce a clique whereby whoever initially gains power will hold
it and prevent its "enemies" from getting in too. This will make
the toplevel rather less than universal.
(E-mail from Robert Elton Maas to the namedroppers mailing list on 9
November 1983)
My basic point is that as a world-wide network evolves it is
ridiculous to force people to name resources in terms of one
static hierarchy which very closely resembles the current
internetwork topology (as the current scheme does). What we are
eventually going to require is a distributed expert for making
sense out of a name someone hands it. There will be no simple
algorithm to be written on one page of an RFC that will suffice to
resolve a name. Rather, a number of heuristics will let a
resolver make sense out of a given name by querying other experts
which it suspects may be more knowledgeable about the name than it
is, or by forwarding a piece of mail to an expert which is at
least one level closer to the destination in some hierarchy.
(E-mail from Peter Karp to the namedroppers mailing list on 8
February 1984)
A.3. Change History
A.3.1. draft-adpkja-special-names-problem-00 A.2.1. draft-adpkja-special-names-problem-00
Initial draft circulated for comment. Initial draft circulated for comment.
Appendix B. Change history Appendix B. Change history
[ RFC Editor: Please remove this section before publication] [ RFC Editor: Please remove this section before publication]
-01 to -02: -01 to -02:
o A very large number of readability / grammar / reference fixes o A very large number of readability / grammar / reference fixes
skipping to change at page 18, line 18 skipping to change at page 8, line 18
-00 to -01: -00 to -01:
o Significant readability changes. o Significant readability changes.
-00: -00:
o Initial draft circulated for comment. o Initial draft circulated for comment.
Authors' Addresses Authors' Addresses
Joe Abley Geoff Huston
Dyn, Inc. APNIC
103-186 Albert Street
London, ON N6A 1M1
Canada
Phone: +1 519 670 9327 Email: gih@apnic.net
Email: jabley@dyn.com
Peter Koch Peter Koch
DENIC eG DENIC eG
Kaiserstrasse 75-77 Kaiserstrasse 75-77
Frankfurt 60329 Frankfurt 60329
Germany Germany
Email: pk@denic.de Email: pk@denic.de
Alain Durand Alain Durand
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