Internet DRAFT - draft-ietf-dnsop-attrleaf
draft-ietf-dnsop-attrleaf
dnsop D. Crocker
Internet-Draft Brandenburg InternetWorking
Intended status: Standards Track November 16, 2018
Expires: May 20, 2019
DNS Scoped Data Through "Underscore" Naming of Attribute Leaves
draft-ietf-dnsop-attrleaf-16
Abstract
Formally, any DNS resource record may occur under any domain name.
However some services use an operational convention for defining
specific interpretations of an RRset, by locating the records in a
DNS branch, under the parent domain to which the RRset actually
applies. The top of this subordinate branch is defined by a naming
convention that uses a reserved node name, which begins with an
_underscore. The underscored naming construct defines a semantic
scope for DNS record types that are associated with the parent
domain, above the underscored branch. This specification explores
the nature of this DNS usage and defines the "DNS Global Underscore
Scoped Entry Registry" with IANA. The purpose of the Underscore
registry is to avoid collisions resulting from the use of the same
underscore-based name, for different services.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
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."
This Internet-Draft will expire on May 20, 2019.
Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Underscore Scoping . . . . . . . . . . . . . . . . . . . 3
1.2. Scaling Benefits . . . . . . . . . . . . . . . . . . . . 4
1.3. "Global" Underscored Node Names . . . . . . . . . . . . . 5
1.4. Interaction with DNS wildcards . . . . . . . . . . . . . 5
1.5. History . . . . . . . . . . . . . . . . . . . . . . . . . 5
2. DNS Underscore Scoped Entry Registries Function . . . . . . . 6
3. RRset Use Registration Template . . . . . . . . . . . . . . . 7
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
4.1. DNS Underscore Global Scoped Entry Registry . . . . . . . 8
4.2. DNS Underscore Global Scoped Entry Registry Definition . 8
4.3. Initial entries . . . . . . . . . . . . . . . . . . . . . 9
4.4. _ta . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.5. _example . . . . . . . . . . . . . . . . . . . . . . . . 10
4.6. Enumservices Registrations Registry . . . . . . . . . . . 11
5. Guidance for Expert Review . . . . . . . . . . . . . . . . . 11
6. Security Considerations . . . . . . . . . . . . . . . . . . . 11
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 11
7.1. Normative References . . . . . . . . . . . . . . . . . . 11
7.2. References - Informative . . . . . . . . . . . . . . . . 14
7.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 14
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction
The core Domain Name System (DNS) technical specifications assign no
semantics to domain names or their parts, and no constraints upon
which resource record (RR) types are permitted to be stored under
particular names [RFC1035], [RFC2181]. Over time, some leaf node
names, such as "www" and "ftp" have come to imply support for
particular services, but this is a matter of operational convention,
rather than defined protocol semantics. This freedom in the basic
technology has permitted a wide range of administrative and semantic
policies to be used -- in parallel. DNS data semantics have been
limited to the specification of particular resource record types, on
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the expectation that new resource record types would be added as
needed. Unfortunately, the addition of new resource record types has
proven extremely challenging, over the life of the DNS, with
significant adoption and use barriers.
1.1. Underscore Scoping
As an alternative to defining a new RR type, some DNS service
enhancements call for using an existing resource record type, but
specify a restricted scope for its occurrence. Scope is meant as a
static property, not one dependent on the nature of the query. It is
an artifact of the DNS name. That scope is a leaf node, containing
the specific resource record sets can be formally defined and
constrained.
The leaf occurs in a branch having a distinguished naming
convention: There is a parent domain name to which the scoped data
applies. The branch is under this name. The sub-branch is
indicated by a sequence of one or more reserved DNS node names; at
least the first (highest) of these names begins with an underscore
("_").
Because the DNS rules for a "host" (host name) do not allow use of
the underscore character, this distinguishes the underscored name
from all legal host names [RFC952]. Effectively, this convention for
leaf node naming creates a space for the listing of "attributes" --
in the form of resource record types -- that are associated with the
parent domain, above the underscored sub-branch.
The scoping feature is particularly useful when generalized resource
record types are used -- notably "TXT", "SRV", and "URI" [RFC1035],
[RFC2782], [RFC6335], [RFC7553]. It provides efficient separation of
one use of them from others. Absent this separation, an
undifferentiated mass of these RRsets is returned to the DNS client,
which then must parse through the internals of the records in the
hope of finding ones that are relevant. Worse, in some cases the
results are ambiguous because a record type might not adequately
self-identify its specific purpose. With underscore-based scoping,
only the relevant RRsets are returned.
A simple example is DKIM [RFC6376] , which uses "_domainkey" for
defining a place to hold a TXT record containing signing information
for the parent domain.
This specification formally defines how underscored labels are used
as "attribute" enhancements for their parent domain names. For
example, domain name "_domainkey.example." acts as an attribute of
the parent domain name "example." To avoid collisions resulting from
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the use of the same underscore-based labels for different
applications using the same resource record type, this document
establishes the DNS Underscore Global Scoped Entry IANA Registry.
Use of such node names, which begin with underscore, are reserved
when they are the underscored name closest to the DNS root; they are
considered "global". Underscore-based names that are farther down
the hierarchy are handled within the scope of the global underscore
name.
Discussion Venue: Discussion about this draft should be directed
to the dnsop@ietf.org [1] mailing list.
NOTE TO RFC EDITOR: Please remove "Discussion Venue" paragraph
prior to publication.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
1.2. Scaling Benefits
Some resource record types are used in a fashion that can create
scaling problems, if an entire RRset associated with a domain name is
aggregated in the leaf node for that name. An increasingly-popular
approach, with excellent scaling properties, places the RRset under a
specially named branch, which is in turn under the node name that
would otherwise contain the RRset. The rules for naming that branch
define the context for interpreting the RRset. That is, rather than:
domain-name.example
/
RRset
the arrangement is:
_branch.domain-name.example
/
RRset
A direct lookup to the subordinate leaf node produces only the
desired record types, at no greater cost than a typical DNS lookup.
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1.3. "Global" Underscored Node Names
As defined in [RFC1034] the DNS uses names organized in a tree-
structured, or hierarchical fashion. A domain name might have
multiple node names that begin with an _underscore. A "global"
underscored node name is the one that is closest to the root of the
DNS hierarchy, also called the highest-level or top-most. In the
presentation convention described in Section 3.1 of [RFC1034] this is
the right-most name beginning with an underscore. In other
presentation environments it might be positioned differently. To
avoid concern for the presentation variations, the qualifier "global"
is used here.
1.4. Interaction with DNS wildcards
DNS wildcards interact poorly with underscored names in two ways.
Since wildcards only are interpreted as leaf names, one cannot create
the equivalent of a wildcard name for prefixed names. A name such as
label.*.example.com is not a wildcard.
Conversely, a wildcard such as *.example.com can match any name
including an underscored name. So, a wildcard might match an
underscored name, returning a record that is the type controlled by
the underscored name but is not intended to be used in the
underscored context and does not conform to its rules.
1.5. History
Originally different uses of underscore-based node names developed
largely without coordination. For TXT records, there is no
consistent, internal syntax that permits distinguishing among the
different uses. In the case of the SRV RR and URI RR, distinguishing
among different types of use was part of the design [RFC2782],
[RFC7553]. The SRV and URI specifications serve as templates,
defining RRs that might only be used for specific applications when
there is an additional specification. The template definition
included reference to two levels of tables of names from which
underscore-names should be drawn. The lower-level (local scope) set
of "_service" names is defined in terms of other IANA tables, namely
any table with symbolic names. The upper-level (global scope) SRV
naming field is "_proto", although its pool of names is not
explicitly defined.
The aggregate effect of these independent efforts was a long list of
underscore-based names that were reserved without coordination, which
invites an eventual name-assignment collision. The remedy is this
base document, which defines a registry for these names, and attempts
to register all those already in use, with a companion document
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[attrleaf-fix] developed to direct changes to the pre-registry
specifications that used underscore-based (global) node names.
2. DNS Underscore Scoped Entry Registries Function
A registry for "global" DNS node names that begin with an underscore
is defined here. The purpose of the Underscore Global Registry is to
avoid collisions resulting from the use of the same underscore-based
name, for different applications.
o If a public specification calls for use of an underscore-prefixed
domain node name, the "global" underscored name -- the underscored
name that is closest to the DNS root -- MUST be entered into this
registry.
An underscored name defines the scope of use for specific resource
record types, which are associated with the domain name that is the
"parent" to the branch defined by the underscored name. A given name
defines a specific, constrained context for one or more RR types,
where use of such record types conforms to the defined constraints.
o Within an underscore scoped leaf, other RRsets that are not
specified as part of the scope MAY be used.
Structurally, the registry is defined as a single, flat table of RR
types, under node names beginning with underscore. In some cases,
such as for use of an SRV record, the full scoping name might be
multi-part, as a sequence of underscored names. Semantically, that
sequence represents a hierarchical model and it is theoretically
reasonable to allow re-use of a subordinate underscored name in a
different, global underscored context; that is, a subordinate name is
meaningful only within the scope of the global underscored name.
Therefore they are ignored by this DNS Underscore Global Scoped Entry
Registry. This registry is for the definition of highest-level --
ie, global -- underscored node name used.
+----------------------------+
| NAME |
+----------------------------+
| _service1 |
| _protoB._service2 |
| _protoB._service3 |
| _protoC._service3 |
| _useX._protoD._service4 |
| _protoE._region._authority |
+----------------------------+
Table 1: Examples of Underscored Names
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Only global underscored names are registered in the IANA Underscore
Global table. From the example, that would mean registering
"_service3", "_service4", and "_authority" are registered in the IANA
_service1, _service2, _service3, _service 4, and _authority.
o The use of underscored node names is specific to each RRTYPE that
is being scoped. Each name defines a place, but does not define
the rules for what appears underneath that place, either as
additional underscored naming or as a leaf node with resource
records. Details for those rules are provided by specifications
for individual RRTYPEs. The sections below describe the way that
existing underscore labels are used with the RRTYPEs that they
name.
o Definition and registration of subordinate, underscore node names
is the responsibility of the specification that creates the global
registry entry.
That is, if a scheme using a global underscore node name has one or
more subordinate levels of underscore node naming, the namespaces
from which names for those lower levels are chosen are controlled by
the parent underscore node name. Each globally-registered underscore
name owns a distinct, subordinate name space.
3. RRset Use Registration Template
This section provides a basic template that can be used to register
new entries in the IANA DNS Underscore Global Scoped Entry Registry,
if the global underscored name above the RRTYPE is not already
registered. The text can be added to specifications using
RRTYPE/_Node-name combinations that have not already been registered:
Per {RFC Attrleaf} please add the following entry to the DNS
Underscore Global Scoped Entry Registry:
+----------+-------------------+------------------------------------+
| RR Type | _NODE NAME | REFERENCE |
+----------+-------------------+------------------------------------+
| {RRTYPE} | _{DNS global node | {citation for the document making |
| | name} | the addition.} |
+----------+-------------------+------------------------------------+
Table 2: Underscore Global Registry Entry Template
Note to RFC Editor: Please replace the above "{RFC Attrleaf}" text
with a reference to this document's RFC number. /d
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4. IANA Considerations
Per [RFC8126] IANA is requested to establish the:
DNS Underscore Global Scoped Entry Registry
This section describes actions requested of IANA. The guidance in
[IANA] is used.
4.1. DNS Underscore Global Scoped Entry Registry
The DNS Global Underscore Scoped Entry Registry is any DNS node name
that begin with the underscore character ("_", ASCII 0x5F) and is the
underscored node name closest to the root; that is it defines the
highest-level of a DNS branch, under a "parent" domain name.
o This registry is to operate under the IANA rules for "Expert
Review" registration; see Section 5.
o The contents of each entry in the Global registry are defined in
Section 4.2.
o Each entry in the registry MUST contain values for all of the
fields specified in Section 4.2.
o Within the registry, the combination of RR Type and _Node Name
MUST be unique.
o The table is to be maintained with entries sorted by the first
column (RR Type) and, within that, the second column (_Node Name).
o The required Reference for an entry MUST have a stable resolution
to the organization controlling that registry entry.
4.2. DNS Underscore Global Scoped Entry Registry Definition
A registry entry contains:
RR Type: Lists an RR type that is defined for use within this
scope.
_Node Name: Specifies a single, underscored name that defines a
reserved name; this name is the "global" entry name for
the scoped resource record types that are associated
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with that name; for characters in the name that have an
upper-case form and a lower-case form, the character
MUST be recorded as lower-case, to simplify name
comparisons.
References: Lists the specification that defines a record type
and its use under this _Node Name. The organization
producing the specification retains control over the
registry entry for the _Node Name.
Each RR type that is to be used with a _Node Name MUST have a
separate registry entry.
4.3. Initial entries
Initial entries in the registry are:
+------------+---------------------+-------------+
| RR Type | _NODE NAME | REFERENCE |
+------------+---------------------+-------------+
| * | _example | Section 4.5 |
| NULL | _ta-* {Section 4.4} | [RFC8145] |
| OPENPGPKEY | _openpgpkey | [RFC7929] |
| SMIMEA | _smimecert | [RFC8162] |
| SRV | _dccp | [RFC2782] |
| SRV | _http | [RFC4386] |
| SRV | _ipv6 | [RFC5026] |
| SRV | _ldap | [RFC4386] |
| SRV | _ocsp | [RFC4386] |
| SRV | _sctp | [RFC2782] |
| SRV | _sip | [RFC5509] |
| SRV | _tcp | [RFC2782] |
| SRV | _udp | [RFC2782] |
| SRV | _xmpp | [RFC3921] |
| TLSA | _dane | [RFC7671] |
| TLSA | _sctp | [RFC6698] |
| TLSA | _tcp | [RFC6698] |
| TLSA | _udp | [RFC6698] |
| TXT | _acme-challenge | [ACME] |
| TXT | _dmarc | [RFC7489] |
| TXT | _domainkey | [RFC6376] |
| TXT | _mta-sts | [MTA-STS] |
| TXT | _spf | [RFC7208] |
| TXT | _tcp | [RFC6763] |
| TXT | _udp | [RFC6763] |
| TXT | _vouch | [RFC5518] |
| URI | _acct | [RFC6118] |
| URI | _dccp | [RFC7566] |
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| URI | _email | [RFC6118] |
| URI | _ems | [RFC6118] |
| URI | _fax | [RFC6118] |
| URI | _ft | [RFC6118] |
| URI | _h323 | [RFC6118] |
| URI | _iax | [RFC6118] |
| URI | _ical-access | [RFC6118] |
| URI | _ical-sched | [RFC6118] |
| URI | _ifax | [RFC6118] |
| URI | _im | [RFC6118] |
| URI | _mms | [RFC6118] |
| URI | _pres | [RFC6118] |
| URI | _pstn | [RFC6118] |
| URI | _sctp | [RFC6118] |
| URI | _sip | [RFC6118] |
| URI | _sms | [RFC6118] |
| URI | _tcp | [RFC6118] |
| URI | _udp | [RFC6118] |
| URI | _unifmsg | [RFC6118] |
| URI | _vcard | [RFC6118] |
| URI | _videomsg | [RFC6118] |
| URI | _voice | [RFC6118] |
| URI | _voicemsg | [RFC6118] |
| URI | _vpim | [RFC6118] |
| URI | _web | [RFC6118] |
| URI | _xmpp | [RFC6118] |
+------------+---------------------+-------------+
Table 3: Underscore Global Registry (initial entries)
NOTE: Under the NULL RR, the entry "_ta-*" denotes all node names
beginning with the string "_ta-*". It does NOT refer to a DNS
wildcard specification.
4.4. _ta
Under the NULL RR, the entry "_ta-*" denotes all node names beginning
with the string "_ta-*". It does NOT refer to a DNS wildcard
specification.
4.5. _example
The node name "_example" is reserved across all RRsets
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4.6. Enumservices Registrations Registry
Please add a note to the Enumservice Registrations registry with the
following -- or similar -- language:
"When adding an entry to this registry, strong consideration
should be given to also adding an entry to the 'DNS Underscore
Global Scoped Entry Registry'."
5. Guidance for Expert Review
This section provides guidance for expert review of registration
requests in the DNS Underscore Global Scoped Entry Registry.
This review is solely to determine adequacy of a requested entry
in this Registry, and does not include review of other aspects of
the document specifying that entry. For example such a document
might also contain a definition of the resource record type that
is referenced by the requested entry. Any required review of that
definition is separate from the expert review required here.
The review is for the purposes of ensuring that:
o The details for creating the registry entry are sufficiently
clear, precise and complete
o The combination of the underscored name, under which the listed
resource record type is used, and the resource record type, is
unique in the table
For the purposes of this Expert Review, other matters of the
specification's technical quality, adequacy or the like are outside
of scope.
6. Security Considerations
This memo raises no security issues.
7. References
7.1. Normative References
[ACME] Barnes, R., Hoffman-Andrews, J., McCarney, D., and J.
Kasten, "Automatic Certificate Management Environment
(ACME)", I-D draft-ietf-acme-acme-11, March 2018.
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[IANA] M. Cotton, B. Leiba, and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", RFC 8126,
June 2017.
[MTA-STS] Margolis, D., Risher, M., Ramakrishnan, B., Brotman, A.,
and J. Jones, "SMTP MTA Strict Transport Security (MTA-
STS)", I-D draft-ietf-uta-mta-sts.
[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.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2181] Elz, R. and R. Bush, "Clarifications to the DNS
Specification", RFC 2181, July 1997.
[RFC2782] Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for
specifying the location of services (DNS SRV)", RFC 2782,
February 2000.
[RFC3921] Saint-Andre, P., Ed., "Extensible Messaging and Presence
Protocol (XMPP): Instant Messaging and Presence",
RFC 3921, DOI 10.17487/RFC3921, October 2004,
<https://www.rfc-editor.org/info/rfc3921>.
[RFC4386] Boeyen, S. and P. Hallam-Baker, "Internet X.509 Public Key
Infrastructure Repository Locator Service", RFC 4386,
DOI 10.17487/RFC4386, February 2006,
<https://www.rfc-editor.org/info/rfc4386>.
[RFC5026] Giaretta, G., Ed., Kempf, J., and V. Devarapalli, Ed.,
"Mobile IPv6 Bootstrapping in Split Scenario", RFC 5026,
DOI 10.17487/RFC5026, October 2007,
<https://www.rfc-editor.org/info/rfc5026>.
[RFC5509] Loreto, S., "Internet Assigned Numbers Authority (IANA)
Registration of Instant Messaging and Presence DNS SRV RRs
for the Session Initiation Protocol (SIP)", RFC 5509,
DOI 10.17487/RFC5509, April 2009,
<https://www.rfc-editor.org/info/rfc5509>.
[RFC5518] Hoffman, P., Levine, J., and A. Hathcock, "Vouch By
Reference", RFC 5518, April 2009.
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[RFC6118] Hoeneisen, B. and A. Mayrhofer, "Update of Legacy IANA
Registrations of Enumservices", RFC 6118,
DOI 10.17487/RFC6118, March 2011,
<https://www.rfc-editor.org/info/rfc6118>.
[RFC6335] Cotton, M., Eggert, L., Tpuch, J., Westerlund, M., and S.
Cheshire, "nternet Assigned Numbers Authority (IANA)
Procedures for the Management of the Service Name and
Transport Protocol Port Number Registry", RFC 6335, Aug
2011.
[RFC6376] Crocker, D., Hansen, T., and M. Kucherawy, "DomainKeys
Identified Mail (DKIM) Signatures", RFC 6376, Sept 2011.
[RFC6698] Hoffman, J. and J. Schlyter, "The DNS-Based Authentication
of Named Entities (DANE) Transport Layer Security (TLS)
Protocol: TLSA", RFC 6698, August .
[RFC6763] Cheshire, S. and M. Krochmal, "DNS-Based Service
Discovery", RFC 6763, DOI 10.17487/RFC6763, February 2013,
<https://www.rfc-editor.org/info/rfc6763>.
[RFC7208] Kitterman, S., "Sender Policy Framework (SPF) for
Authorizing Use of Domains in E-Mail, Version 1",
RFC 7208, April 2014.
[RFC7489] Kucherawy, M., Ed. and E. Zwicky, Ed., "Domain-based
Message Authentication, Reporting, and Conformance
(DMARC)", RFC 7489, March 2015.
[RFC7553] Falstrom, P. and O. Kolkman, "The Uniform Resource
Identifier (URI) DNS Resource Record", RFC 7553,
ISSN 2070-1721, June 2015.
[RFC7566] Goix, L. and K. Li, "Enumservice Registration for 'acct'
URI", RFC 7566, DOI 10.17487/RFC7566, June 2015,
<https://www.rfc-editor.org/info/rfc7566>.
[RFC7671] Dukhovni, V. and W. Hardaker, "The DNS-Based
Authentication of Named Entities (DANE) Protocol: Updates
and Operational Guidance", RFC 7671, DOI 10.17487/RFC7671,
October 2015, <https://www.rfc-editor.org/info/rfc7671>.
[RFC7929] Wouters, P., , RFC 7929, August 2016.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", RFC 8126,
June 2017.
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[RFC8145] Wessels, D., Kumari, W., and P. Hoffman, "Signaling Trust
Anchor Knowledge in DNS Security Extensions (DNSSEC)",
RFC 8145, April 2017.
[RFC8162] Hoffman, P. and J. Schlyter, "Using Secure DNS to
Associate Certificates with Domain Names for S/MIME",
RFC 8162, May 2017.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC952] Harrenstien, K., Stahl, M., and E. Feinler, "DOD Internet
Host Table Specification", RFC 952, October 1985.
7.2. References - Informative
[attrleaf-fix]
Crocker, D., "Changes to Rationalize Underscore DNS Node
Names", I-D draft-crocker-attrleaf-simplification-00,
2017.
7.3. URIs
[1] mailto:dnsop@ietf.org
Appendix A. Acknowledgements
Thanks go to Bill Fenner, Dick Franks, Tony Hansen, Martin Hoffmann,
Paul Hoffman, Peter Koch, Olaf Kolkman, Murray Kucherawy, John
Levine, Benno Overeinder, and Andrew Sullivan for diligent review of
the (much) earlier drafts. For the later enhancements, thanks to:
Stephane Bortzmeyer, Alissa Cooper, Bob Harold, Benjamin Kaduk, Mirja
Kuehlewind, Warren Kumari, John Levine, Joel Jaeggli, Benno
Overeinder, Eric Rescorla, Adam Roach, Petr Špaček,
Ondřej Sury, Paul Vixie, Tim Wicinski, and Paul Wouters.
Special thanks to Ray Bellis for his persistent encouragement to
continue this effort, as well as the suggestion for an essential
simplification to the registration model.
NOTE TO RFC EDITOR: The listed names Petr Špaček,
Ondřej Sury -- Petr Špaček, Ondřej Sury --
render properly in xml-to-html conversion but the production
xml2rfc engine does not render it properly to text. Making the
xml version match the documented form for txt will mean that the
names are not properly rendered for output formats that can
support extended character sets. /d
Crocker Expires May 20, 2019 [Page 14]
Internet-Draft DNS AttrLeaf November 2018
Author's Address
Dave Crocker
Brandenburg InternetWorking
675 Spruce Dr.
Sunnyvale, CA 94086
USA
Phone: +1.408.246.8253
Email: dcrocker@bbiw.net
URI: http://bbiw.net/
Crocker Expires May 20, 2019 [Page 15]
