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dnsop                                                         D. Crocker
Internet-Draft                               Brandenburg InternetWorking
Updates: 2782, 3263, 3404, 3529, 3620,                  October 10, 2018
         3832, 3861, 3887, 6121, 3958,
         4120, 4227, 4386, 4387, 4976,
         5026, 5328, 5389, 5415, 5518,
         5555, 5617, 5679, 5766, 5780,
         5804, 5864, 5928, 6011, 6120,
         6186, 6376, 6733, 6763, 7208,
         7489, 8145 (if approved)
Intended status: Standards Track
Expires: April 13, 2019


 DNS Attrleaf Changes: Fixing Specifications with Underscored Node Name
                                  Use
                    draft-ietf-dnsop-attrleaf-fix-05

Abstract

   Original uses of an underscore character as a domain node name
   prefix, which creates a space for constrained interpretation of
   resource records, were specified without the benefit of an IANA
   registry.  This produced an entirely uncoordinated set of name-
   creation activities, all drawing from the same namespace.  A registry
   now has been defined.  However the existing specifications that use
   underscore naming need to be modified, to be in line with the new
   registry.  This document specifies those changes.  The changes
   preserve existing software and operational practice, while adapting
   the specifications for those practices to the newer underscore
   registry model.

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 April 13, 2019.



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Copyright Notice

   Copyright (c) 2018 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   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
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Underscored RRset Use in Specifications . . . . . . . . . . .   3
     2.1.  TXT RRset Use . . . . . . . . . . . . . . . . . . . . . .   3
     2.2.  SRV RRset Use . . . . . . . . . . . . . . . . . . . . . .   4
     2.3.  URI RRset Use . . . . . . . . . . . . . . . . . . . . . .   5
   3.  Underscored Template Specifications . . . . . . . . . . . . .   6
     3.1.  SRV Specification Changes . . . . . . . . . . . . . . . .   6
     3.2.  URI Specification Changes . . . . . . . . . . . . . . . .   7
     3.3.  DNSSEC Signaling Specification Changes  . . . . . . . . .   9
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  10
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   6.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
     6.1.  Normative References  . . . . . . . . . . . . . . . . . .  10
     6.2.  References -- Informative . . . . . . . . . . . . . . . .  10
   Appendix A.  Acknowledgements . . . . . . . . . . . . . . . . . .  14
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  14

1.  Introduction

   Original uses of an underscore character as a domain node name
   [RFC1035] prefix, which creates a space for constrained
   interpretation of resource records, were specified without the
   benefit of an [IANA-reg] registry.  This produced an entirely
   uncoordinated set of name-creation activities, all drawing from the
   same namespace.  A registry has been now defined, and that document
   discusses the background for underscored domain name use [Attrleaf].

   The basic model for underscored name registration, as specified in
   [Attrleaf], is to have each registry entry be unique in terms of the
   combination of a resource record type and a 'global' (highest-level)




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   underscored name; that is, the node name beginning with an
   underscore, which is the closest to the DNS root.

   The existing uses of underscored naming have specifications that do
   not reflect the existence of this integrated registry.  For the new
   reader or the new editor of one of those documents, there is
   currently nothing signaling that the underscore name(s) defined in
   the document are now processed through an IANA registry.  This
   document remedies that, by marking such a published document with an
   update, indicating the nature of the change.

   Further, the documents that define the SRV [RFC2782] and URI
   [RFC7553] DNS resource records provide a meta-template for
   underscored name assignments, partially based on separate registries
   [RFC6335].  For the portion that selects the global (highest-level)
   underscored name, this perpetuates uncoordinated assignment
   activities by separate technical specifications, out of the same name
   space.  This document remedies that by providing detail for revisions
   to the SRV and URI specifications, to bring their use in line with
   the single, integrated global underscore registry.

   The result of these changes preserves existing software and
   operations practices, while adapting the technical specifications to
   the newer underscore registry model.

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

2.  Underscored RRset Use in Specifications

   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.

2.1.  TXT RRset Use

   This section provides a generic approach for changes to existing
   specifications that define straightforward use of underscored node
   names, when scoping the use of a "TXT" RRset.  The approach provides
   the information needed for adapting such specifications to the use of
   the IANA DNS Underscore Global Scoped Entry Registry [Attrleaf].
   Hence the approach is meant both as an update to these existing




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   specifications, and as guidance for changes when those documents are
   revised.

   For any document that specifies the use of a "TXT" RRset under one or
   more underscored names, that 'global' name is expected to be
   registered in the IANA DNS Underscore Global Scoped Entry Registry
   [Attrleaf].  An effort has been made to locate existing drafts that
   do this, register the global underscored names, and list them in the
   initial set of names added to the registry.

   Note that a public specification, which defines use of an RRset and
   calls for the use of an underscore-prefixed domain name, its global
   underscored name -- the one closest to the root -- is required to be
   entered into this registry, if it is not already registered.
   [Attrleaf].

   Here is a template of suggested text for this to appear in the IANA
   Considerations section of the specification:

      "Per" [Attrleaf] "please add the following entry to the DNS
      Underscore Global Scoped Entry Registry:"

   +--------+----------------+-----------------------------------------+
   | RR     | _NODE NAME     | REFERENCE                               |
   | Type   |                |                                         |
   +--------+----------------+-----------------------------------------+
   | TXT    | _{DNS node     | {citation for the document making the   |
   |        | name}          | addition.}                              |
   +--------+----------------+-----------------------------------------+

                 Table 1: Underscore Global Registry Entry

2.2.  SRV RRset Use

   Specification for the SRV [RFC2782] resource record provides a
   template for use of underscored node names.  The global name is
   characterised as referencing the 'protocol' that is associated with
   "SRV" RRset usage.

   This section provides a generic approach for changes to existing
   specifications that define the use of an "SRV" RRset.  The approach
   provides the information needed for adapting such specifications to
   the use of the IANA DNS Underscore Global Scoped Entry Registry
   [Attrleaf].  Hence the approach is meant both as an update to these
   existing specifications, and as guidance for changes when those
   documents are revised.





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   For any document that specifies the use of an "SRV" RRset, the global
   ('protocol') underscored name is expected to be registered in the
   IANA DNS Underscore Global Scoped Entry Registry [Attrleaf].  An
   effort has been made to locate existing drafts that do this, register
   the global underscored names, and list them in the initial set of
   names added to the registry.

   Note that a public specification, which defines use of an RRset and
   calls for the use of an underscore-prefixed domain name, its global
   underscored name -- the one closest to the root -- is required to be
   entered into this registry, if it is not already registered.
   [Attrleaf].

   Here is a template of suggested text for this to appear in the IANA
   Considerations section of the specification:

      "Per" [Attrleaf] "please add the following entry to the DNS
      Underscore Global Scoped Entry Registry:"

   +--------+----------------------+-----------------------------------+
   | RR     | _NODE NAME           | REFERENCE                         |
   | Type   |                      |                                   |
   +--------+----------------------+-----------------------------------+
   | SRV    | _{DNS 'protocol'     | {citation for the document making |
   |        | node name}           | the addition.}                    |
   +--------+----------------------+-----------------------------------+

                 Table 2: Underscore Global Registry Entry

2.3.  URI RRset Use

   Specification for the URI [RFC7553] resource record provides a
   template for use of underscored node names.  The global name is
   characterised as naming the 'protocol' that is associated with "URI"
   RR usage or by reversing an Enumservice sequence [RFC6117].

   This section provides a generic approach for changes to existing
   specifications that define use of a "URI" RRset.  The approach
   provides the information needed for adapting such specifications to
   the use of the IANA DNS Underscore Global Scoped Entry Registry
   [Attrleaf].  Hence the approach is meant both as an update to these
   existing specifications, and as guidance for changes when those
   documents are revised.

   For any document that specifies the use of a "URI" RRset, the global
   ('protocol' or highest-level enumservice) underscored name is
   expected to be registered in the IANA DNS Underscore Global Scoped
   Entry Registry [Attrleaf].  An effort has been made to locate



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   existing drafts that do this and register the associated 'protocol'
   names.

   Note that a public specification, which defines use of an RRset and
   calls for the use of an underscore-prefixed domain name, its global
   underscored name -- the one closest to the root -- is required to be
   entered into this registry, if it is not already registered.
   [Attrleaf].

   Here is a template of suggested text for this to appear in the IANA
   Considerations section of the specification:

      "Per" [Attrleaf] "please add the following entry to the DNS
      Underscore Global Scoped Entry Registry:"

   +-------+---------------------------+-------------------------------+
   | RR    | _NODE NAME                | REFERENCE                     |
   | Type  |                           |                               |
   +-------+---------------------------+-------------------------------+
   | URI   | _{DNS 'protocol' or       | {citation for the document    |
   |       | Enumservice node name}    | making the addition.}         |
   +-------+---------------------------+-------------------------------+

                 Table 3: Underscore Global Registry Entry

3.  Underscored Template Specifications

3.1.  SRV Specification Changes

   The specification for a domain name, under which an SRV [RFC2782]
   resource record appears, provides a template for use of underscored
   node names.  The global underscored name, is characterised as
   indicating the 'protocol' that is associated with "SRV" RR usage.

   Text of that existing specification is changed as follows:

      OLD:














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   The format of the SRV RR

    Here is the format of the SRV RR, whose DNS type code is 33:
          _Service._Proto.Name TTL Class SRV Priority Weight Port Target
    ...
    Proto
         The symbolic name of the desired protocol, with an underscore
         (_) prepended to prevent collisions with DNS labels that occur
         in nature.  _TCP and _UDP are at present the most useful values
         for this field, though any name defined by Assigned Numbers or
         locally may be used (as for Service).  The Proto is case
         insensitive.

      NEW:

         The format of the SRV RR



         Here is the format of the SRV RR, whose DNS type code is 33:



            "_Service._Proto.Name TTL Class SRV Priority Weight Port
            Target"

            _..._

         Proto

            The symbolic name of the desired protocol, with an
            underscore (_) prepended to prevent collisions with DNS
            labels that occur in nature. _TCP and _UDP are at present
            the most useful values for this field.  The Proto is case
            insensitive.

            The SRV RRset protocol (global) underscored name SHOULD be
            registered in the IANA DNS Underscore Global Scoped Entry
            Registry [Attrleaf].

3.2.  URI Specification Changes

   Specification for the domain name under which a URI [RFC7553]
   resource record occurs is similar to that for the SRV [RFC2782]
   resource record, although the text refers only to 'service' name,
   rather than distinguishing 'service' from 'protocol'.  Further, the
   URI RR specification permits alternative underscored naming schemes:




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         One matches what is used for "SRV", with the global underscored
         name called "protocol'.

         The other is based on a reversing of an Enumservice [RFC6117]
         sequence.

   Text of that existing specification is changed as follows:

      OLD:

   4.1.  Owner Name, Class, and Type

   The URI owner name is subject to special conventions.

   Just like the SRV RR [RFC2782], the URI RR has service information
   encoded in its owner name.  In order to encode the service for a
   specific owner name, one uses service parameters.  Valid service
   parameters are those registered by IANA in the "Service Name and
   Transport Protocol Port Number Registry" [RFC6335] or as "Enumservice
   ---
   Registrations [RFC6117].  The Enumservice Registration parameters are
   reversed (i.e., subtype(s) before type), prepended with an underscore
   (_), and prepended to the owner name in separate labels.  The
   underscore is prepended to the service parameters to avoid collisions
   with DNS labels that occur in nature, and the order is reversed to
   make it possible to do delegations, if needed, to different zones
   (and therefore providers of DNS).

   For example, suppose we are looking for the URI for a service with
   ENUM Service Parameter "A:B:C" for host example.com.  Then we would
   query for (QNAME,QTYPE)=("_C._B._A.example.com","URI").

   As another example, suppose we are looking for the URI for a service
   with Service Name "A" and Transport Protocol "B" for host
   example.com.  Then we would query for
   (QNAME,QTYPE)=("_A._B.example.com","URI").

      NEW:

         4.1.  Owner Name, Class, and Type

         The URI owner name is subject to special conventions.

         As for the SRV RRset [RFC2782], the URI RRset global (highest-
         level) underscored name SHOULD be registered in the IANA DNS
         Underscore Global Scoped Entry Registry [Attrleaf].





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         Just like the SRV RRset, the URI RRset has service information
         encoded in its owner name.  In order to encode the service for
         a specific owner name, one uses service parameters.  Valid
         service parameters are:

         +  Those registered by IANA in the "Service Name and Transport
            Protocol Port Number Registry" [RFC6335] . The underscore is
            prepended to the service parameters to avoid collisions with
            DNS labels that occur in nature, and the order is reversed
            to make it possible to do delegations, if needed, to
            different zones (and therefore providers of DNS).

         +  Those listed in "Enumservice Registrations" [RFC6117].  The
            Enumservice Registration parameters are reversed (i.e.,
            subtype(s) before type), prepended with an underscore (_),
            and prepended to the owner name in separate labels.  The
            highest-level (global) underscored Enumservice name becomes
            the global Attrleaf name to register.

         For example, suppose we are looking for the URI for a service
         with ENUM Service Parameter "A:B:C" for host example.com.  Then
         we would query for
         (QNAME,QTYPE)=("_C._B._A.example.com","URI").

         As another example, suppose we are looking for the URI for a
         service with Service Name "A" and Transport Protocol "B" for
         host example.com.  Then we would query for
         (QNAME,QTYPE)=("_A._B.example.com","URI").

3.3.  DNSSEC Signaling Specification Changes

   "Signaling Trust Anchor Knowledge in DNS Security Extensions
   (DNSSEC)" [RFC8145] defines a use of DNS node names that effectively
   consumes all names beginning with the string "_ta-", when using the
   NULL RR in the query.

   Text of Section 5.1, "Query Format", of that existing specification,
   is changed as follows:

      OLD:

         For example, a validating DNS resolver ... QNAME=_ta-4444.

      NEW:

         For example, a validating DNS resolver ... QNAME=_ta-4444.





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         Under the NULL RR, an entry is registered in the IANA DNS
         Underscore Global Scoped Entry Registry [Attrleaf] for all node
         names beginning with "_ta-".

4.  IANA Considerations

   Although this document makes reference to IANA registries, it
   introduces no new IANA registries or procedures.

5.  Security Considerations

   This memo raises no security issues.

6.  References

6.1.  Normative References

   [Attrleaf]
              Crocker, D., "DNS Scoped Data Through 'Underscore' Naming
              of Attribute Leaves", I-D draft-ietf-dnsop-attrleaf, 2018.

   [RFC6117]  Hoeneisen, B., Mayrhofer, A., and J. Livingood, "IANA
              Registration of Enumservices: Guide, Template, and IANA
              Considerations", RFC 6117, March 2011.

   [RFC6335]  Cotton, M., Eggert, L., Tpuch, J., Westerlund, M., and S.
              Cheshire, "Internet 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.

   [RFC8145]  Wessels, D., Kumari, W., and P. Hoffman, "Signaling Trust
              Anchor Knowledge in DNS Security Extensions (DNSSEC)",
              RFC 8145, April 2017.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", RFC 8162, May 2017.

6.2.  References -- Informative

   [IANA-reg]
              "Protocol Registries", URL https://www.iana.org/protocols,
              2018.




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   [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.

   [RFC2782]  Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for
              specifying the location of services (DNS SRV)", RFC 2782,
              February 2000.

   [RFC3263]  Rosenberg, J. and H. Schulzrinne, "Session Initiation
              Protocol (SIP): Locating SIP Servers", RFC 3263, June
              2002.

   [RFC3404]  Mealling, M., "Dynamic Delegation Discovery System (DDDS)
              Part Four: The Uniform Resource Identifiers (URI)
              Resolution Application", RFC 3404, October 2002.

   [RFC3529]  Harold, W., "Using Extensible Markup Language-Remote
              Procedure Calling (XML-RPC) in Blocks Extensible Exchange
              Protocol (BEEP)", RFC 3529, April 2003.

   [RFC3620]  New, D., "The TUNNEL Profile", RFC 3620, October 2003.

   [RFC3832]  Columbia University, Columbia University, Sun
              Microsystems, IBM, and IBM, "Remote Service Discovery in
              the Service Location Protocol (SLP) via DNS SRV",
              RFC 3832, July 2004.

   [RFC3861]  Peterson, J., "Address Resolution for Instant Messaging
              and Presence", RFC 3861, August 2004.

   [RFC3887]  "Message Tracking Query Protocol", RFC 3887, September
              2007.

   [RFC3958]  Daigle, L. and A. Newton, "Domain-Based Application
              Service Location Using SRV RRs and the Dynamic Delegation
              Discovery Service (DDDS)", RFC 3958, January 2005.

   [RFC4120]  USC-ISI, MIT, MIT, and MIT, "The Kerberos Network
              Authentication Service (V5)", RFC 4120, July 2005.

   [RFC4227]  O'Tuathail, E. and M. Rose, "Using the Simple Object
              Access Protocol (SOAP) in Blocks Extensible Exchange
              Protocol (BEEP)", RFC 4227, January 2006.






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   [RFC4386]  Boeyen, S. and P. Hallam-Baker, "Internet X.509 Public Key
              Infrastructure: Repository Locator Service", RFC 4386,
              February 2006.

   [RFC4387]  Gutmann, P., Ed., "Internet X.509 Public Key
              Infrastructure Operational Protocols: Certificate Store
              Access via HTTP", RFC 4387, February 2006.

   [RFC4976]  Jennings, C., Mahy, R., and Roach, "Relay Extensions for
              the Message Session Relay Protocol (MSRP)", RFC 4976,
              September 2007.

   [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>.

   [RFC5328]  Adolf, A. and P. MacAvock, "A Uniform Resource Name (URN)
              Namespace for the Digital Video Broadcasting Project
              (DVB)", RFC 5328, September 2008.

   [RFC5389]  Rosenberg, Mahy, Matthews, and Wing, "Session Traversal
              Utilities for NAT (STUN)", RFC 5389, October 2008.

   [RFC5415]  Calhoun, P., Ed., Montemurro, M., Ed., and D. Stanley,
              Ed., "Control And Provisioning of Wireless Access Points
              (CAPWAP) Protocol Specification", RFC 5415, March 2009.

   [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.

   [RFC5555]  Soliman, H., Ed., "Mobile IPv6 Support for Dual Stack
              Hosts and Routers", RFC 5555, June 2009.

   [RFC5617]  Sendmail, Inc., Cisco Systems, Inc., Yahoo! Inc., and
              Taughannock Networks, "DomainKeys Identified Mail (DKIM)
              Author Domain Signing Practices (ADSP)", RFC 5617, August
              2009.

   [RFC5679]  Bajko, G., "Locating IEEE 802.21 Mobility Services Using
              DNS", RFC 5679, December 2009.




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   [RFC5766]  Mahy, R., Matthews, P., and J. Rosenberg, "Traversal Using
              Relays around NAT (TURN): Relay Extensions to Session
              Traversal Utilities for NAT (STUN)", RFC 5766, April 2010.

   [RFC5780]  MacDonald, D. and B. Lowekamp, "NAT Behavior Discovery
              Using Session Traversal Utilities for NAT (STUN)",
              RFC 5780, May 2010.

   [RFC5804]  Melnikov, A., Ed. and T. Martin, "A Protocol for Remotely
              Managing Sieve Scripts", RFC 5804, July 2010.

   [RFC5864]  Allbery, R., "NS SRV Resource Records for AFS", RFC 5864,
              April 2010.

   [RFC5928]  Petit-Huguenin, M., "Traversal Using Relays around NAT
              (TURN) Resolution Mechanism", RFC 5928, August 2010.

   [RFC6011]  Lawrence, S., Ed. and J. Elwell, "Session Initiation
              Protocol (SIP) User Agent Configuration", RFC 6011,
              October 2010.

   [RFC6120]  Saint-Andre, P., "Extensible Messaging and Presence
              Protocol (XMPP): Core", RFC 6120, March 2011.

   [RFC6121]  Saint-Andre, P., Ed., "Extensible Messaging and Presence
              Protocol (XMPP): Instant Messaging and Presence",
              RFC 6121, DOI 10.17487/RFC6121, March 2011,
              <https://www.rfc-editor.org/info/rfc6121>.

   [RFC6186]  Daboo, C., "Use of SRV Records for Locating Email
              Submission/Access Services", RFC 6186, March 2011.

   [RFC6376]  Crocker, D., Hansen, T., and M. Kucherawy, "DomainKeys
              Identified Mail (DKIM) Signatures", RFC 6376, Sept 2011.

   [RFC6733]  Fajardo, V., Ed., Arkko, J., Loughney, J., and G. Zorn,
              Ed., "Diameter Base Protocol", RFC 6733,
              DOI 10.17487/RFC6733, October 2012,
              <https://www.rfc-editor.org/info/rfc6733>.

   [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.




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Internet-Draft              DNS AttrLeaf Fix                October 2018


   [RFC7489]  Kucherawy, M., Ed. and E. Zwicky, Ed., "Domain-based
              Message Authentication, Reporting, and Conformance
              (DMARC)", RFC 7489, March 2015.

   [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>.

Appendix A.  Acknowledgements

   Thanks go to Bill Fenner, Dick Franks, Tony Hansen, Peter Koch, Olaf
   Kolkman, and Andrew Sullivan for diligent review of the (much)
   earlier drafts.  For the later enhancements, thanks to: Tim Wicinski,
   John Levine, Bob Harold, Joel Jaeggli, Ond&#345;ej Sury 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.

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/



















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