draft-ietf-dnsop-attrleaf-06.txt   draft-ietf-dnsop-attrleaf-07.txt 
dnsop D. Crocker dnsop D. Crocker
Internet-Draft Brandenburg InternetWorking Internet-Draft Brandenburg InternetWorking
Intended status: Best Current Practice March 28, 2018 Intended status: Best Current Practice March 31, 2018
Expires: September 29, 2018 Expires: October 2, 2018
DNS Scoped Data Through '_Underscore' Naming of Attribute Leaves DNS Scoped Data Through '_Underscore' Naming of Attribute Leaves
draft-ietf-dnsop-attrleaf-06 draft-ietf-dnsop-attrleaf-07
Abstract Abstract
Formally, any DNS resource record may occur for any domain name. Formally, any DNS resource record may occur for any domain name.
However some services have defined an operational convention, which However some services have defined an operational convention, which
applies to DNS leaf nodes that are under a DNS branch having one or applies to DNS leaf nodes that are under a DNS branch having one or
more reserved node names, each beginning with an underscore. The more reserved node names, each beginning with an underscore. The
underscore naming construct defines a semantic scope for DNS records underscore naming construct defines a semantic scope for DNS record
that are associated with the parent domain, above the underscored types that are associated with the parent domain, above the
branch. This specification explores the nature of this DNS usage and underscored branch. This specification explores the nature of this
defines the "DNS Global Underscore Scoped Entry Registry" with IANA. DNS usage and defines the "DNS Global Underscore Scoped Entry
The purpose of the Underscore registry is to avoid collisions Registry" with IANA. The purpose of the Underscore registry is to
resulting from the use of the same underscore-based name, for avoid collisions resulting from the use of the same underscore-based
different services. name, for different services.
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
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
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 29, 2018. This Internet-Draft will expire on October 2, 2018.
Copyright Notice Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. _Underscore Scoping . . . . . . . . . . . . . . . . . . . 2 1.1. _Underscore Scoping . . . . . . . . . . . . . . . . . . . 2
1.2. Scaling Benefits for TXT, SRV, and URI Resource Records . 3 1.2. Scaling Benefits . . . . . . . . . . . . . . . . . . . . 4
2. DNS Underscore Scoped Entry Registries Function . . . . . . . 4 2. DNS Underscore Scoped Entry Registries Function . . . . . . . 4
2.1. DNS Underscore Global Scoped Entry Registry Definition . 5 2.1. DNS Underscore Global Scoped Entry Registry Definition . 5
3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6
3.1. DNS Underscore Global Scoped Entry Registry . . . . . . . 6 3.1. DNS Underscore Global Scoped Entry Registry . . . . . . . 6
3.2. Guidance for Expert Review . . . . . . . . . . . . . . . 7 3.2. Guidance for Expert Review . . . . . . . . . . . . . . . 7
4. Security Considerations . . . . . . . . . . . . . . . . . . . 8 4. Security Considerations . . . . . . . . . . . . . . . . . . . 8
5. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 5. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
5.1. Normative References . . . . . . . . . . . . . . . . . . 8 5.1. Normative References . . . . . . . . . . . . . . . . . . 8
5.2. References -- Informative . . . . . . . . . . . . . . . . 9 5.2. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 9 Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 9
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 9 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 9
1. Introduction 1. Introduction
The core Domain Name System (DNS) technical specifications assign no The core Domain Name System (DNS) technical specifications assign no
semantics to domain names or their parts, and no constraints upon semantics to domain names or their parts, and no constraints upon
which resource records (RRs) are permitted to be associated with which resource record (RR) types are permitted to be stored under
particular names.[RFC1035] Over time, some leaf node names, such as particular names [RFC1035], [RFC2181]. Over time, some leaf node
"www" and "ftp" have come to imply support for particular services, names, such as "www" and "ftp" have come to imply support for
but this is a matter of operational convention, rather than defined particular services, but this is a matter of operational convention,
protocol semantics. This freedom in the basic technology has rather than defined protocol semantics. This freedom in the basic
permitted a wide range of administrative and semantic policies to be technology has permitted a wide range of administrative and semantic
used -- in parallel. DNS data semantics have been limited to the policies to be used -- in parallel. DNS data semantics have been
specification of particular resource records, on the expectation that limited to the specification of particular resource record types, on
new ones would be added as needed. Unfortunately, the addition of the expectation that new ones would be added as needed.
new resource records has proved extremely challenging, over the life Unfortunately, the addition of new resource record types has proven
of the DNS, with significant adoption and use barriers. extremely challenging, over the life of the DNS, with significant
adoption and use barriers.
1.1. _Underscore Scoping 1.1. _Underscore Scoping
As an alternative to defining new RRs, some DNS service enhancements As an alternative to defining a new RR type, some DNS service
call for using an existing resource record, but specify a restricted enhancements call for using an existing resource record type, but
scope for its occurrence. That scope is a leaf node, within which specify a restricted scope for its occurrence. Scope is meant as a
the uses of specific resource records can be formally defined and 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, within which
the uses of specific resource record sets can be formally defined and
constrained. The leaf occurs in a branch having a distinguished constrained. The leaf occurs in a branch having a distinguished
naming convention: At the top of the branch -- beneath the parent naming convention: At the top of the branch -- beneath the parent
domain name to which the scope applies -- one or more reserved DNS domain name to which the scope applies -- one or more reserved DNS
node names begin with an underscore ("_"). Because the DNS rules for node names begin with an underscore ("_"). Because the DNS rules for
a "host" (host name) are not allowed to use the underscore character, a "host" (host name) are not allowed to use the underscore character,
this distinguishes the underscore name from all legal host names this distinguishes the underscore name from all legal host names
[RFC1035]. Effectively, this convention for leaf node naming creates [RFC952]. Effectively, this convention for leaf node naming creates
a space for the listing of 'attributes' -- in the form of resource a space for the listing of 'attributes' -- in the form of resource
records -- that are associated with the parent domain, above the record types -- that are associated with the parent domain, above the
underscore sub-branch. underscored sub-branch.
The scoping feature is particularly useful when generalized resource The scoping feature is particularly useful when generalized resource
records are used -- notably "TXT", "SRV", and "URI" record types are used -- notably "TXT", "SRV", and "URI" [RFC1035],
[RFC1035],[RFC2782],[RFC6335], [RFC7553]. It provides efficient [RFC2782], [RFC6335], [RFC7553]. It provides efficient separation of
separation of one use of them from others. Absent this separation, one use of them from others. Absent this separation, an
an undifferentiated mass of these "RR"s is returned to the DNS undifferentiated mass of these "RRsets" is returned to the DNS
client, which then must parse through the internals of the records in 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 the hope of finding ones that are relevant. Worse, in some cases the
results are ambiguous because the records do not adequately self- results are ambiguous because a record type might not adequately
identify. With underscore-based scoping, only the relevant "RR"s are self-identify. With underscore-based scoping, only the relevant
returned. "RRsets"s are returned.
A simple example is DKIM [RFC6376] , which uses "_domainkeys" for A simple example is DKIM [RFC6376] , which uses "_domainkeys" for
defining a place to hold a "TXT" record containing signing defining a place to hold a "TXT" record containing signing
information for the parent domain. information for the parent domain.
This specification formally defines how underscore labels are used as This specification formally defines how underscore labels are used as
"attribute" enhancements for their parent domain names. For example, "attribute" enhancements for their parent domain names. For example,
domain name "_domainkey.example." acts as attribute of parent domain domain name "_domainkey.example." acts as attribute of parent domain
name "example." To avoid collisions resulting from the use of the name "example." To avoid collisions resulting from the use of the
same underscore-based labels for different applications, this same underscore-based labels for different applications using the
document establishes DNS Underscore Global Scoped Entry IANA Registry same resource record type, this document establishes DNS Underscore
for the highest-level reserved names that begin with _underscore; Global Scoped Entry IANA Registry for the highest-level reserved
_underscore-based names that are farther down the hierarchy are names that begin with _underscore; _underscore-based names that are
handled within the scope of the highest-level _underscore name. farther down the hierarchy are handled within the scope of the
highest-level _underscore name.
Discussion Venue: Discussion about this draft should be directed Discussion Venue: Discussion about this draft should be directed
to the dnsop@ietf.org [1] mailing list. to the dnsop@ietf.org [1] mailing list.
NOTE TO RFC EDITOR: Please remove "Discussion Venue" paragraph NOTE TO RFC EDITOR: Please remove "Discussion Venue" paragraph
prior to publication. prior to publication.
1.2. Scaling Benefits for TXT, SRV, and URI Resource Records 1.2. Scaling Benefits
Some resource records are generic and support a variety of uses.
Each additional use defines its own rules and, possibly, its own
internal syntax and node-naming conventions to distinguish among
particular types. The "TXT", "SRV", and "URI" records are notable
examples. Their use can scale poorly, particularly when the same
"RR" can be present in the same leaf node, but with different uses.
An increasingly-popular approach, with excellent scaling properties, Some resource record types are used in a fashion that can create
place the RR under a node with an underscore-based name, at a defined scaling problems, if an entire RRset associated with a domain name is
place in the DNS tree, so as to constrain the use of particular "RR"s aggregated in the leaf node for that name. An increasingly-popular
farther down the branch with that name. This means that a direct approach, with excellent scaling properties, places the RRset under a
lookup produces only the desired records, at no greater cost than a node having an underscore-based name, at a defined place in the DNS
typical DNS lookup. tree under the 'parent' name. This constrains the use of particular
"RR" types associated with that parent name. A direct lookup to the
subordinate leaf node produces only the desired record types, at no
greater cost than a typical DNS lookup.
The definition of a underscore global registry, provided in this The definition of a underscore global registry, provided in this
specification, primarily attends to the top-most names used for RRs; specification, primarily attends to the top-most names used for
that is the _underscore "global" names. scoping an RR type; that is the _underscore "global" names.
2. DNS Underscore Scoped Entry Registries Function 2. DNS Underscore Scoped Entry Registries Function
A global registry for DNS nodes names that begin with an _underscore A global registry for DNS nodes names that begin with an _underscore
is defined here. is defined here.
The 'global' (right-most) node name that uses an _underscore The 'global' (right-most) node name that uses an _underscore
prefix MUST be entered into this registry. prefix MUST be entered into this registry.
The names define scope of use for specific resource records, which The names define scope of use for specific resource record types,
are associated with the domain name that is the "parent" to the which are associated with the domain name that is the "parent" to the
branch defined by the _underscore naming. branch defined by the _underscore naming.
A given name defines a specific, constrained context for one or A given name defines a specific, constrained context for one or
more RR records, in which use of such records MUST conform to the more RR types, in which use of such record types MUST conform to
defined constraints. Within this scope, other resource records the defined constraints. Within this scope, other RRsets that are
that are not specified MAY be used. not specified MAY be used.
The purpose of the Underscore Global Registry is to avoid collisions The purpose of the Underscore Global Registry is to avoid collisions
resulting from the use of the same _underscore-based name, for resulting from the use of the same _underscore-based name, for
different applications. different applications.
The DNS Global Underscore Registry MUST have entries that are The DNS Global Underscore Registry MUST have entries that are
unique with respect to the combination of the listed resource unique with respect to the combination of the listed resource
record and the listed, global underscore node name (RR, _Node record type and the listed, global underscore node name (RR Type,
Name). _Node Name).
Structurally, the registry is defined as a single, flat table of Structurally, the registry is defined as a single, flat table of RR
names that begin with _underscore. In some cases, such as for use of types, under node names beginning with _underscore. In some cases,
an "SRV" record, the full scoping name might be multi-part, as a such as for use of an "SRV" record, the full scoping name might be
sequence of underscore names. Semantically, that sequence represents multi-part, as a sequence of underscore names. Semantically, that
a hierarchical model and it is theoretically reasonable to allow re- sequence represents a hierarchical model and it is theoretically
use of a subordinate underscore name in different underscore context; reasonable to allow re-use of a subordinate underscore name in
that is, a subordinate name is meaningful only within the scope of different underscore context; that is, a subordinate name is
the first (top-level) underscore name. Therefore they are ignored by meaningful only within the scope of the right-most (top-level)
this DNS Underscore Global Scoped Entry Registry. This registry is underscore name. Therefore they are ignored by this DNS Underscore
for the definition of highest-level -- ie, global -- underscore node Global Scoped Entry Registry. This registry is for the definition of
name used. highest-level -- ie, global -- underscore node name used.
+----------------------------+ +----------------------------+
| NAME | | NAME |
+----------------------------+ +----------------------------+
| _service1 | | _service1 |
| ._protoB._service2 | | ._protoB._service2 |
| _protoB._service3 | | _protoB._service3 |
| _protoC._service3 | | _protoC._service3 |
| _useX._protoD._service4 | | _useX._protoD._service4 |
| _protoE._region._authority | | _protoE._region._authority |
skipping to change at page 5, line 39 skipping to change at page 5, line 41
one or more subordinate levels of underscore node naming, the one or more subordinate levels of underscore node naming, the
namespaces from which names for those lower levels is chosen is namespaces from which names for those lower levels is chosen is
controlled by the parent underscore node name. Each globally- controlled by the parent underscore node name. Each globally-
registered underscore name owns a distinct, subordinate name registered underscore name owns a distinct, subordinate name
space. space.
2.1. DNS Underscore Global Scoped Entry Registry Definition 2.1. DNS Underscore Global Scoped Entry Registry Definition
A registry entry contains: A registry entry contains:
RR: Lists the RR that are defined for use within this scope. RR Type: Lists an RR type that is defined for use within this
scope.
_Node Name: Specifies a single _underscore name that defines a _Node Name: Specifies a single _underscore name that defines a
reserved name; this name is the "global" entry name for the reserved name; this name is the "global" entry name for the
scoped resource records that are associated with that name scoped resource record types that are associated with that
name
References Lists specification that define the records and their use References: Lists specification that defines a record type and its
under this Name. The organization producing the use under this Name. The organization producing the
specification retains control over the registry entry for specification retains control over the registry entry for
the _Node Name. the _Node Name.
Each RR that is to be used MUST have a separate registry entry. Each RR type that is to be used MUST have a separate registry entry.
3. IANA Considerations 3. IANA Considerations
Per [RFC8126], IANA is requested to establish the: Per [RFC8126], IANA is requested to establish the:
DNS Underscore Global Scoped Entry Registry DNS Underscore Global Scoped Entry Registry
This section describes actions requested of IANA. The guidance in This section describes actions requested of IANA. The guidance in
[IANA] is used. [IANA] is used.
3.1. DNS Underscore Global Scoped Entry Registry 3.1. DNS Underscore Global Scoped Entry Registry
The DNS Global Underscore Scoped Entry Registry is for DNS node names The DNS Global Underscore Scoped Entry Registry is for DNS node names
that begin with the underscore character (_) and are the first that begin with the underscore character (_) and are the right-most
occurrence of any names in a domain name sequence having that form; occurrence of any names in a domain name sequence having that form;
that is they are the "top" of a DNS branch and are shown as the that is they are the "top" of a DNS branch and are shown as the
right-most _underscore name -- under a "parent" domain name. right-most _underscore name -- under a "parent" domain name.
o This registry is to operate under the IANA rules for "Expert o This registry is to operate under the IANA rules for "Expert
Review" registration; see Section 3.2. Review" registration; see Section 3.2.
o The contents of each entry in the Global registry are defined in o The contents of each entry in the Global registry are defined in
Section 2.1. Section 2.1.
o The table is to be maintained with entries sorted by the first o The table is to be maintained with entries sorted by the first
column (RR) and within that the second column (_Node Name). column (RR Type) and within that the second column (_Node Name).
o The required Reference for an entry MUST have a stable resolution o The required Reference for an entry MUST have a stable resolution
to the organization controlling that registry entry to the organization controlling that registry entry
Initial entries in the registry are: Initial entries in the registry are:
+------------+-----------------+------------+ +------------+-----------------+------------+
| RR | _NODE NAME | REFERENCE | | RR Type | _NODE NAME | REFERENCE |
+------------+-----------------+------------+ +------------+-----------------+------------+
| OPENPGPKEY | _openpgpkey | [RFC7929] | | OPENPGPKEY | _openpgpkey | [RFC7929] |
| SMIMEA | _smimecert | [RFC8162] | | SMIMEA | _smimecert | [RFC8162] |
| SRV | _dccp | [RFC2782] | | SRV | _dccp | [RFC2782] |
| SRV | _sctp | [RFC2782] | | SRV | _sctp | [RFC2782] |
| SRV | _tcp | [RFC2782] | | SRV | _tcp | [RFC2782] |
| SRV | _udp | [RFC2782] | | SRV | _udp | [RFC2782] |
| TLSA | _sctp | [RFC6698] | | TLSA | _sctp | [RFC6698] |
| TLSA | _tcp | [RFC6698] | | TLSA | _tcp | [RFC6698] |
| TLSA | _udp | [RFC6698] | | TLSA | _udp | [RFC6698] |
| TXT | _acme-challenge | [ACME] | | TXT | _acme-challenge | [ACME] |
| TXT | _domainkey | [RFC6376] | | TXT | _domainkey | [RFC6376] |
| TXT | _dmarc | [RFC7489] | | TXT | _dmarc | [RFC7489] |
| TXT | _spf | [RFC7208] | | TXT | _spf | [RFC7208] |
| TXT | _vouch | [RFC5518] | | TXT | _vouch | [RFC5518] |
| URI | _??? | | | URI | _dccp | [RFC7553] |
| URI | _sctp | [RFC7553] |
| URI | _tcp | [RFC7553] |
| URI | _udp | [RFC7553] |
+------------+-----------------+------------+ +------------+-----------------+------------+
Table 1: Underscore Global Registry (initial entries) Table 1: Underscore Global Registry (initial entries)
3.2. Guidance for Expert Review 3.2. Guidance for Expert Review
This section provides guidance for expert review of registration This section provides guidance for expert review of registration
requests in the of DNS Underscore Global Scoped Entry Registry. requests in the of DNS Underscore Global Scoped Entry Registry.
This review is solely to determine adequacy of a requested entry This review is solely to determine adequacy of a requested entry
in this Registry, and does not include review of other aspects of in this Registry, and does not include review of other aspects of
the document specifying that entry. For example such a document the document specifying that entry. For example such a document
might also contain a definition of the resource record that is might also contain a definition of the resource record type that
referenced by the requested entry. Any required review of that is referenced by the requested entry. Any required review of that
definition is separate from the expert review required here. definition is separate from the expert review required here.
The review is for the purposes of ensuring that: The review is for the purposes of ensuring that:
o The details for creating the registry entry are sufficiently o The details for creating the registry entry are sufficiently
clear, precise and complete clear, precise and complete
o The combination of the _underscore name, under which the listed o The combination of the _underscore name, under which the listed
resource record is used, and the resource record, is unique in the resource record type is used, and the resource record type, is
table unique in the table
For the purposes of this Expert Review, other matters of the For the purposes of this Expert Review, other matters of the
specification's technical quality, adequacy or the like are outside specification's technical quality, adequacy or the like are outside
of scope. of scope.
4. Security Considerations 4. Security Considerations
This memo raises no security issues. This memo raises no security issues.
5. References 5. References
5.1. Normative References 5.1. Normative References
[ACME] Barnes, R., Hoffman-Andrews, J., McCarney, D., and J. [ACME] Barnes, R., Hoffman-Andrews, J., McCarney, D., and J.
Kasten, "Automatic Certificate Management Environment Kasten, "Automatic Certificate Management Environment
(ACME)", I-D draft-ietf-acme-acme-11, March 2018. (ACME)", I-D draft-ietf-acme-acme-11, March 2018.
[IANA] M. Cotton, B. Leiba, and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", RFC 8126,
June 2017.
[RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, November 1987.
[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 [RFC2782] Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for
specifying the location of services (DNS SRV)", RFC 2782, specifying the location of services (DNS SRV)", RFC 2782,
February 2000. February 2000.
[RFC5518] Hoffman, P., Levine, J., and A. Hathcock, "Vouch By [RFC5518] Hoffman, P., Levine, J., and A. Hathcock, "Vouch By
Reference", RFC 5518, April 2009. Reference", RFC 5518, April 2009.
[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 [RFC6376] Crocker, D., Hansen, T., and M. Kucherawy, "DomainKeys
Identified Mail (DKIM) Signatures", RFC 6376, Sept 2011. Identified Mail (DKIM) Signatures", RFC 6376, Sept 2011.
[RFC6698] Hoffman, J. and J. Schlyter, "The DNS-Based Authentication [RFC6698] Hoffman, J. and J. Schlyter, "The DNS-Based Authentication
of Named Entities (DANE) Transport Layer Security (TLS) of Named Entities (DANE) Transport Layer Security (TLS)
Protocol: TLSA", RFC 6698, August . Protocol: TLSA", RFC 6698, August .
[RFC7208] Kitterman, S., "Sender Policy Framework (SPF) for [RFC7208] Kitterman, S., "Sender Policy Framework (SPF) for
Authorizing Use of Domains in E-Mail, Version 1", Authorizing Use of Domains in E-Mail, Version 1",
RFC 7208, April 2014. RFC 7208, April 2014.
[RFC7489] Kucherawy, M., Ed. and E. Zwicky, Ed., "Domain-based [RFC7489] Kucherawy, M., Ed. and E. Zwicky, Ed., "Domain-based
Message Authentication, Reporting, and Conformance Message Authentication, Reporting, and Conformance
(DMARC)", RFC 7489, March 2015. (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.
[RFC7929] Wouters, P., , RFC 7929, August 2016. [RFC7929] Wouters, P., , RFC 7929, August 2016.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", RFC 8126, Writing an IANA Considerations Section in RFCs", RFC 8126,
June 2017. June 2017.
[RFC8162] Hoffman, P. and J. Schlyter, "Using Secure DNS to [RFC8162] Hoffman, P. and J. Schlyter, "Using Secure DNS to
Associate Certificates with Domain Names for S/MIME", Associate Certificates with Domain Names for S/MIME",
RFC 8162, May 2017. RFC 8162, May 2017.
5.2. References -- Informative [RFC952] Harrenstien, K., Stahl, M., and E. Feinler, "DOD Internet
Host Table Specification", RFC 952, October 1985.
[IANA] M. Cotton, B. Leiba, and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", RFC 8126,
June 2017.
[RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, November 1987.
[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.
[RFC7553] Falstrom, P. and O. Kolkman, "The Uniform Resource
Identifier (URI) DNS Resource Record", RFC 7553,
ISSN 2070-1721, June 2015.
5.3. URIs 5.2. URIs
[1] mailto:dnsop@ietf.org [1] mailto:dnsop@ietf.org
Appendix A. Acknowledgements Appendix A. Acknowledgements
Thanks go to Bill Fenner, Tony Hansen, Peter Koch, Olaf Kolkman, and Thanks go to Bill Fenner, Tony Hansen, Peter Koch, Olaf Kolkman, and
Andrew Sullivan for diligent review of the (much) earlier drafts. Andrew Sullivan for diligent review of the (much) earlier drafts.
For the later enhancements, thanks to: Stephane Bortzmeyer, Bob For the later enhancements, thanks to: Stephane Bortzmeyer, Bob
Harold, John Levine, Joel Jaeggli, Petr Špaček, Ondřej Harold, John Levine, Joel Jaeggli, Petr Špaček, Ondřej
Surř, Tim Wicinski, and Paul Wouters. Surř, Tim Wicinski, and Paul Wouters.
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