Internet DRAFT - draft-hoeneisen-rfc5333bis

draft-hoeneisen-rfc5333bis






Network Working Group                                       B. Hoeneisen
Internet-Draft                                                   Ucom.ch
Obsoletes: 5333 (if approved)                             March 11, 2012
Updates: 6118 (if approved)
Intended status: Informational
Expires: September 12, 2012


       IANA Registration of Enumservices for Internet Calendaring
                     draft-hoeneisen-rfc5333bis-01

Abstract

   This document registers and obsoletes Enumservices for Internet
   calendaring.  Specifically, this document focuses on Enumservices for
   iMIP (iCalendar Message-Based Interoperability Protocol), CalDAV
   (Calendaring Extensions to WebDAV), and iSchedule (Internet Calendar
   Scheduling Protocol).

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 http://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 September 12, 2012.

Copyright Notice

   Copyright (c) 2012 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
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of



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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
   outside the IETF Standards Process, and derivative works of it may
   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4

   2.  Enumservice Registrations  . . . . . . . . . . . . . . . . . .  5
     2.1.  ical-access:http (obsoletion)  . . . . . . . . . . . . . .  6
     2.2.  ical-access:https (obsoletion) . . . . . . . . . . . . . .  7
     2.3.  ical-sched:mailto (obsoletion) . . . . . . . . . . . . . .  8
     2.4.  ical-access:caldav-http (new)  . . . . . . . . . . . . . .  9
     2.5.  ical-access:caldav-https (new) . . . . . . . . . . . . . . 10
     2.6.  ical-sched:imip-mailto (new) . . . . . . . . . . . . . . . 11
     2.7.  ical-sched:ischedule (new) . . . . . . . . . . . . . . . . 12
     2.8.  ical-sched:ischedules (new)  . . . . . . . . . . . . . . . 13
     2.9.  ical-sched:caldav-http (new) . . . . . . . . . . . . . . . 14
     2.10. ical-sched:caldav-https (new)  . . . . . . . . . . . . . . 15
     2.11. Requesters' Addresses  . . . . . . . . . . . . . . . . . . 16

   3.  Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

   4.  Security Considerations  . . . . . . . . . . . . . . . . . . . 16

   5.  DNS Considerations . . . . . . . . . . . . . . . . . . . . . . 17

   6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 17

   7.  Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 17

   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 18
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 18
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 19

   Appendix A.  Document Changelog  . . . . . . . . . . . . . . . . . 19



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   Appendix B.  Open Issues . . . . . . . . . . . . . . . . . . . . . 20

   Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 20
















































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1.  Introduction

   ENUM (E.164 Number Mapping) [RFC6116] is a system that uses DNS
   (Domain Name System, [RFC1034]) to translate telephone numbers, such
   as '+12025550100', into URIs (Uniform Resource Identifiers,
   [RFC3986]), such as 'mailto:user@example.com'.  ENUM exists primarily
   to facilitate the interconnection of systems that rely on telephone
   numbers with those that use URIs to identify resources.  The ENUM
   registration here could be used to allow phones, for example, to
   check the free/busy status of a user in their address book or propose
   a meeting with him or her from the user's phone number.

   The Guide to Internet Calendaring [RFC3283] describes the
   relationship between various Internet calendaring specifications like
   this: "iCalendar [RFC5545] is the language used to describe calendar
   objects.  iTIP (iCalendar Transport-Independent Interoperability
   Protocol) [RFC5546] describes a way to use the iCalendar language to
   do scheduling.  iMIP (iCalendar Message-Based Interoperability
   Protocol) [RFC2447] describes how to do iTIP scheduling via e-mail".

   Recently, other Standards Track protocols for calendar and scheduling
   access have appeared.  CalDAV (Calendaring Extensions to WebDAV)
   [RFC4791] is a WebDAV (Web-based Distributed Authoring and
   Versioning) [RFC4918] based mechanism for manipulating Internet
   calendars, viewing free/busy lists, and via a scheduling extension
   [I-D.desruisseaux-caldav-sched], could be used for proposing calendar
   events as well in the future.  Similarly, iSchedule (Internet
   Calendar Scheduling Protocol) [I-D.desruisseaux-ischedule] can be
   used for scheduling.

   The existing 'mailto:' URI scheme (defined in [RFC6068]) is already
   used to address iMIP compatible Calendar Services.  Likewise, the
   existing 'http:' and 'https:' URI schemes (defined in [RFC2616] and
   [RFC2818]) are already used to address CalDAV compatible Calendar
   Services.  To allow for other protocols based on iTIP using the same
   URI schemes in future, the Subtype is no longer named after the URI
   scheme only.

   This document obsoletes the existing Calendaring Enumservices
   specified in [RFC5333] and in Sections 4.7 - 4.9 of [RFC6118] and
   adds new Enumservices for iMIP [RFC2447], WebDAV
   [I-D.desruisseaux-caldav-sched], and iSchedule
   [I-D.desruisseaux-ischedule].

   This document obsoletes [RFC5333] as well as Sections 4.7 - 4.9 of
   [RFC6118].





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2.  Enumservice Registrations

   As defined in [RFC6117], the following templates cover the
   information needed for the registration of the Enumservices specified
   in this document:

   [Note for RFC Editor: Please perform this following tasks before
   publication of this document:
   o  replace any instance of "RFCTHIS" with the RFC number of this
      document;
   o  replace any instance of "I-D.desruisseaux-caldav-sched" with the
      RFC number of that document;
   o  replace any instance of "I-D.desruisseaux-ischedule" with the RFC
      number of that document;
   o  verify references pointing to specific sections of this document,
      in particular in the <security> elements.
   ]


































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2.1.  ical-access:http (obsoletion)

   <record>
     <!-- ical-access:http -->
     <class>Application-Based, Common</class>
     <type>ical-access</type>
     <subtype>http</subtype>
     <urischeme>http</urischeme>
     <functionalspec>
       <paragraph>
         This Enumservice indicates that the resource identified
         can be addressed by the associated URI in order to access
         a user's calendar (for example free/busy status) using
         the CalDAV [RFC 4791] protocol for Internet calendaring.
       </paragraph>
     </functionalspec>
     <security>
       See <xref type="rfc" data="rfcTHIS" />, Section 4.
     </security>
     <usage>OBSOLETE</usage>
     <registrationdocs>
       <xref type="rfc" data="rfc5333" />
             (obsoleted by <xref type="rfc" data="rfcTHIS" />)
       <xref type="rfc" data="rfc6118" />
             (obsoleted by <xref type="rfc" data="rfcTHIS" />)
       <xref type="rfc" data="rfcTHIS" />
     </registrationdocs>
     <additionalinfo>
       This Enumservice has been replaced by 'ical-access:caldav-http'.
     </additionalinfo>
     <requesters>
       <xref type="person" data="Rohan_Mahy" />
       <xref type="person" data="Bernie_Hoeneisen" />
     </requesters>
   </record>
















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2.2.  ical-access:https (obsoletion)

   <record>
     <!-- ical-access:https -->
     <class>Application-Based, Common</class>
     <type>ical-access</type>
     <subtype>https</subtype>
     <urischeme>https</urischeme>
     <functionalspec>
       <paragraph>
         This Enumservice indicates that the resource identified
         can be addressed by the associated URI in order to access
         a user's calendar (for example free/busy status) using
         the CalDAV [RFC 4791] protocol for Internet calendaring.
       </paragraph>
     </functionalspec>
     <security>
       See <xref type="rfc" data="rfcTHIS" />, Section 4.
     </security>
     <usage>OBSOLETE</usage>
     <additionalinfo>
       This Enumservice has been replaced by 'ical-access:caldav-https'.
     </additionalinfo>
     <registrationdocs>
       <xref type="rfc" data="rfc5333" />
             (obsoleted by <xref type="rfc" data="rfcTHIS" />)
       <xref type="rfc" data="rfc6118" />
             (obsoleted by <xref type="rfc" data="rfcTHIS" />)
       <xref type="rfc" data="rfcTHIS" />
     </registrationdocs>
     <requesters>
       <xref type="person" data="Rohan_Mahy" />
       <xref type="person" data="Bernie_Hoeneisen" />
     </requesters>
   </record>
















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2.3.  ical-sched:mailto (obsoletion)

   <record>
     <!-- ical-sched:mailto -->
     <class>Application-Based, Common</class>
     <type>ical-sched</type>
     <subtype>mailto</subtype>
     <urischeme>mailto</urischeme>
     <functionalspec>
       <paragraph>
         This Enumservice indicates that the resource identified
         can be addressed by the associated URI used for
         scheduling using Internet calendaring via Internet mail
         with the iMIP [RFC 2447] protocol.
       </paragraph>
     </functionalspec>
     <security>
       See <xref type="rfc" data="rfcTHIS" />, Section 4.
     </security>
     <usage>OBSOLETE</usage>
     <registrationdocs>
       <xref type="rfc" data="rfc5333" />
             (obsoleted by <xref type="rfc" data="rfcTHIS" />)
       <xref type="rfc" data="rfc6118" />
             (obsoleted by <xref type="rfc" data="rfcTHIS" />)
       <xref type="rfc" data="rfcTHIS" />
     </registrationdocs>
     <additionalinfo>
       This Enumservice has been replaced by 'ical-sched:imip'.
     </additionalinfo>
     <requesters>
       <xref type="person" data="Rohan_Mahy" />
       <xref type="person" data="Bernie_Hoeneisen" />
     </requesters>
   </record>
















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2.4.  ical-access:caldav-http (new)

   <record>
     <!-- ical-access:caldav-http -->
     <class>Application-Based, Common</class>
     <type>ical-access</type>
     <subtype>caldav-http</subtype>
     <urischeme>http</urischeme>
     <functionalspec>
       <paragraph>
         This Enumservice indicates that the resource identified
         can be addressed by the associated URI in order to access
         a user's calendar (for example free/busy status) using
         the CalDAV [RFC 4791] protocol for Internet calendaring.
       </paragraph>
     </functionalspec>
     <security>
       See <xref type="rfc" data="rfcTHIS" />, Section 4.
     </security>
     <usage>COMMON</usage>
     <registrationdocs>
       <xref type="rfc" data="rfcTHIS" />
     </registrationdocs>
     <requesters>
       <xref type="person" data="Bernie_Hoeneisen" />
     </requesters>
   </record>
























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2.5.  ical-access:caldav-https (new)

   <record>
     <!-- ical-access:caldav-https -->
     <class>Application-Based, Common</class>
     <type>ical-access</type>
     <subtype>caldav-https</subtype>
     <urischeme>https</urischeme>
     <functionalspec>
       <paragraph>
         This Enumservice indicates that the resource identified
         can be addressed by the associated URI in order to access
         a user's calendar (for example free/busy status) using
         the CalDAV [RFC 4791] protocol for Internet calendaring.
       </paragraph>
     </functionalspec>
     <security>
       See <xref type="rfc" data="rfcTHIS" />, Section 4.
     </security>
     <usage>COMMON</usage>
     <registrationdocs>
       <xref type="rfc" data="rfcTHIS" />
     </registrationdocs>
     <requesters>
       <xref type="person" data="Bernie_Hoeneisen" />
     </requesters>
   </record>
























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2.6.  ical-sched:imip-mailto (new)

   <record>
     <!-- ical-sched:imip-mailto -->
     <class>Application-Based, Common</class>
     <type>ical-sched</type>
     <subtype>imip-mailto</subtype>
     <urischeme>mailto</urischeme>
     <functionalspec>
       <paragraph>
         This Enumservice indicates that the resource identified
         can be addressed by the associated URI used for
         scheduling using Internet calendaring via Internet mail
         with the iMIP [RFC 2447] protocol.
       </paragraph>
     </functionalspec>
     <security>
       See <xref type="rfc" data="rfcTHIS" />, Section 4.
     </security>
     <usage>COMMON</usage>
     <registrationdocs>
       <xref type="rfc" data="rfcTHIS" />
     </registrationdocs>
     <requesters>
       <xref type="person" data="Bernie_Hoeneisen" />
     </requesters>
   </record>
























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2.7.  ical-sched:ischedule (new)

   <record>
     <!-- ical-sched:ischedule -->
     <class>Application-Based, Common</class>
     <type>ical-sched</type>
     <subtype>ischedule</subtype>
     <urischeme>http</urischeme>
     <functionalspec>
       <paragraph>
         This Enumservice indicates that the resource identified can be
         addressed by the associated URI used for scheduling using
         the iSchedule [I-D.desruisseaux-ischedule] protocol.
       </paragraph>
     </functionalspec>
     <security>
       See <xref type="rfc" data="rfcTHIS" />, Section 4.
     </security>
     <usage>COMMON</usage>
     <registrationdocs>
       <xref type="rfc" data="rfcTHIS" />
     </registrationdocs>
     <requesters>
       <xref type="person" data="Bernie_Hoeneisen"/>
     </requesters>
   </record>

























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2.8.  ical-sched:ischedules (new)

   <record>
     <!-- ical-sched:ischedules -->
     <class>Application-Based, Common</class>
     <type>ical-sched</type>
     <subtype>ischedules</subtype>
     <urischeme>https</urischeme>
     <functionalspec>
       <paragraph>
         This Enumservice indicates that the resource identified can be
         addressed by the associated URI used for scheduling using
         the iSchedule [I-D.desruisseaux-ischedule] protocol.
       </paragraph>
     </functionalspec>
     <security>
       See <xref type="rfc" data="rfcTHIS" />, Section 4.
     </security>
     <usage>COMMON</usage>
     <registrationdocs>
       <xref type="rfc" data="rfcTHIS" />
     </registrationdocs>
     <requesters>
       <xref type="person" data="Bernie_Hoeneisen" />
     </requesters>
   </record>

























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2.9.  ical-sched:caldav-http (new)

   TODO: Do we need this one?

   <record>
     <!-- ical-sched:caldav-http -->
     <class>Application-Based, Common</class>
     <type>ical-sched</type>
     <subtype>caldav-http</subtype>
     <urischeme>http</urischeme>
     <functionalspec>
       <paragraph>
         This Enumservice indicates that the resource identified can be
         addressed by the associated URI used for scheduling using
         Internet calendaring via the scheduling extension
         [I-D.desruisseaux-caldav-sched] to the CalDAV [RFC 4791]
         protocol.
       </paragraph>
     </functionalspec>
     <security>
       See <xref type="rfc" data="rfcTHIS" />, Section 4.
     </security>
     <usage>COMMON</usage>
     <registrationdocs>
       <xref type="rfc" data="rfcTHIS" />
     </registrationdocs>
     <requesters>
       <xref type="person" data="Bernie_Hoeneisen"/>
     </requesters>
   </record>





















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2.10.  ical-sched:caldav-https (new)

   <record>
     <!-- ical-sched:caldav-https -->
     <class>Application-Based, Common</class>
     <type>ical-sched</type>
     <subtype>caldav-https</subtype>
     <urischeme>https</urischeme>
     <functionalspec>
       <paragraph>
         This Enumservice indicates that the resource identified can be
         addressed by the associated URI used for scheduling using
         Internet calendaring via the scheduling extension
         [I-D.desruisseaux-caldav-sched] to the CalDAV [RFC 4791]
         protocol.
       </paragraph>
     </functionalspec>
     <security>
       See <xref type="rfc" data="rfcTHIS" />, Section 4.
     </security>
     <usage>COMMON</usage>
     <registrationdocs>
       <xref type="rfc" data="rfcTHIS" />
     </registrationdocs>
     <requesters>
       <xref type="person" data="Bernie_Hoeneisen" />
     </requesters>
   </record>























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2.11.  Requesters' Addresses

   <people>

     <person id="Rohan_Mahy">
       <name>Rohan Mahy</name>
       <org>Unaffiliated</org>
       <uri>mailto:rohan&ekabal.com</uri>
       <updated>2009-10</updated>
     </person>

     <person id="Bernie_Hoeneisen">
       <name>Bernie Hoeneisen</name>
       <org>Ucom Standards Track Solutions GmbH</org>
       <uri>mailto:bernhard.hoeneisen@ucom.ch</uri>
       <updated>2012-03</updated>
     </person>

   </people>


3.  Examples

   TODO: More Examples

   $ORIGIN 3.2.1.0.5.5.5.2.1.2.1.e164.arpa.
   @ NAPTR 10 100 "u" "E2U+ical-access:caldav-https" \
      "!^.*$!https://cal.example.com/home/alice/calendars/!" .

   $ORIGIN 3.2.1.0.5.5.5.2.1.2.1.e164.arpa.
   @ NAPTR 20 100 "u" "E2U+ical-sched:imip" \
      "!^.*$!mailto:alice@example.com!" .


4.  Security Considerations

   The Domain Name System (DNS) does not make policy decisions about
   which records it provides to a DNS resolver.  All DNS records must be
   assumed to be available to all inquirers at all times.  The
   information provided within an ENUM record set must therefore be
   considered open to the public -- which is a cause for some privacy
   considerations.

   Revealing a calendaring URI by itself is unlikely to introduce many
   privacy concerns, although, depending on the structure of the URI, it
   might reveal the full name or employer of the target.  The use of
   anonymous URIs mitigates this risk.




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   As ENUM uses DNS, which in its current form is an insecure protocol,
   there is no mechanism for ensuring that the answer returned to a
   query is authentic.  An analysis of threats specific to the
   dependence of ENUM on the DNS is provided in [RFC6116], and a
   thorough analysis of threats to the DNS itself is covered in
   [RFC3833].  Many of these problems are prevented when the resolver
   verifies the authenticity of answers to its ENUM queries via DNSSEC
   (DNS Security, [RFC4035]) in zones where it is available.

   More serious security concerns are associated with potential attacks
   against an underlying calendaring system (for example, unauthorized
   modification or viewing).  For this reason, iTIP discusses a number
   of security requirements (detailed in [RFC5546]) that call for
   authentication, integrity and confidentiality properties, and similar
   measures to prevent such attacks.  Any calendaring protocol used in
   conjunction with a URI scheme currently meets these requirements.
   The use of CalDAV with the 'https:' scheme makes use of TLS
   (Transport Layer Security, [RFC5246]) to provide server
   authentication, confidentiality, and message integrity.

   Unlike a traditional telephone number, the resource identified by a
   calendaring URI is often already guessable, and it often requires
   that users provide cryptographic credentials for authentication and
   authorization before calendar data can be exchanged.  Despite the
   public availability of ENUM records, the use of this information to
   reveal an unprotected calendaring resource is unlikely in practice.


5.  DNS Considerations

   These Enumservice registrations add no specific issues related to
   DNS.


6.  IANA Considerations

   This document requests registration of the "ical-sched" and "ical-
   access" Enumservices according to the definitions in Section 2 of
   this document and [RFC6117].


7.  Acknowledgments

   The author would like to thank Cyrus Daboo, Bernard Desruisseaux, and
   Alfred Hoenes for providing feedback resulting in improvement of this
   document.

   As this document obsoletes [RFC5333], please see also the Authors'



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   and Acknowledgments sections in RFC 5333 for additional
   acknowledgments.


8.  References

8.1.  Normative References

   [I-D.desruisseaux-caldav-sched]
              Daboo, C. and B. Desruisseaux, "CalDAV Scheduling
              Extensions to WebDAV", draft-desruisseaux-caldav-sched-10
              (work in progress), September 2011.

   [I-D.desruisseaux-ischedule]
              Daboo, C. and B. Desruisseaux, "Internet Calendar
              Scheduling Protocol (iSchedule)",
              draft-desruisseaux-ischedule-01 (work in progress),
              March 2010.

   [RFC1034]  Mockapetris, P., "Domain names - concepts and facilities",
              STD 13, RFC 1034, November 1987.

   [RFC2447]  Dawson, F., Mansour, S., and S. Silverberg, "iCalendar
              Message-Based Interoperability Protocol (iMIP)", RFC 2447,
              November 1998.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, January 2005.

   [RFC4035]  Arends, R., Austein, R., Larson, M., Massey, D., and S.
              Rose, "Protocol Modifications for the DNS Security
              Extensions", RFC 4035, March 2005.

   [RFC4791]  Daboo, C., Desruisseaux, B., and L. Dusseault,
              "Calendaring Extensions to WebDAV (CalDAV)", RFC 4791,
              March 2007.

   [RFC4918]  Dusseault, L., "HTTP Extensions for Web Distributed
              Authoring and Versioning (WebDAV)", RFC 4918, June 2007.

   [RFC5333]  Mahy, R. and B. Hoeneisen, "IANA Registration of
              Enumservices for Internet Calendaring", RFC 5333,
              October 2009.

   [RFC5545]  Desruisseaux, B., "Internet Calendaring and Scheduling
              Core Object Specification (iCalendar)", RFC 5545,
              September 2009.



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   [RFC5546]  Daboo, C., "iCalendar Transport-Independent
              Interoperability Protocol (iTIP)", RFC 5546,
              December 2009.

   [RFC6068]  Duerst, M., Masinter, L., and J. Zawinski, "The 'mailto'
              URI Scheme", RFC 6068, October 2010.

   [RFC6116]  Bradner, S., Conroy, L., and K. Fujiwara, "The E.164 to
              Uniform Resource Identifiers (URI) Dynamic Delegation
              Discovery System (DDDS) Application (ENUM)", RFC 6116,
              March 2011.

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

   [RFC6118]  Hoeneisen, B. and A. Mayrhofer, "Update of Legacy IANA
              Registrations of Enumservices", RFC 6118, March 2011.

8.2.  Informative References

   [RFC2616]  Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
              Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
              Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.

   [RFC2818]  Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000.

   [RFC3283]  Mahoney, B., Babics, G., and A. Taler, "Guide to Internet
              Calendaring", RFC 3283, June 2002.

   [RFC3833]  Atkins, D. and R. Austein, "Threat Analysis of the Domain
              Name System (DNS)", RFC 3833, August 2004.

   [RFC5246]  Dierks, T. and E. Rescorla, "The Transport Layer Security
              (TLS) Protocol Version 1.2", RFC 5246, August 2008.


Appendix A.  Document Changelog

   [RFC Editor: This section is to be removed before publication]

   draft-hoeneisen-rfc5333bis-01
   o  bernie: References 6116-18 updated
   o  bernie: Obsoleted (replaced, introduced new Subtype) old services
      (based on Feedback from Cyrus)
   o  bernie: Changed Subtype Enumservices for WebDAV scheduling





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   o  bernie: Introduced Enumservices for iSchedule
   o  bernie: Added lots of open issues

   draft-hoeneisen-rfc5333bis-00 (compared to RFC 5333)
   o  bernie: Updated References: 2445 -> 5545, 2446 -> 5546
   o  bernie: Updated existing Enumservices to be in line with RFC 6117
   o  bernie: Added new Enumservices for WebDAV scheduling
   o  bernie: several editorials


Appendix B.  Open Issues

   [RFC Editor: This section should be removed before publication]
   o  Major: Do we need "ical-sched:caldav-http[s]"?  If yes, do we need
      "ical-sched:caldav-http"?
   o  Major: Should we introduce a "ical-fb" Type for freebusy
      information or is "ical-access" sufficient to cover this?
   o  Medium: Include reference to RFC 6350, Section 6.9.
   o  Medium: Does it make sense to derive Calendaring related
      Enumservices for http or ftp as described in RFC 6350, Section
      6.9.?
   o  Minor: References in citation: should those be RFC244[5-6] or
      RFC554[5-6]?
   o  Minor: Reference to RFC 5689 (Updates RFC 4791) needed?
   o  Minor: Should Rohan be listed as author?
   o  Minor: More examples


Author's Address

   Bernie Hoeneisen
   Ucom Standards Track Solutions GmbH
   CH-8000 Zuerich
   Switzerland

   Phone: +41 44 500 52 44
   Email: bernie@ietf.hoeneisen.ch (bernhard.hoeneisen AT ucom.ch)
   URI:   http://www.ucom.ch/













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