Internet Engineering Task Force (IETF)                          A. Tamas
Request for Comments: 8589                               B. Phister, Ed.
Category: Informational                                   J-E. Rodriguez
ISSN: 2070-1721                                                    OP3FT
                                                                May 2019


                     The 'leaptofrogans' URI Scheme

Abstract

   This document describes the 'leaptofrogans' Uniform Resource
   Identifier (URI) scheme, which enables applications to launch Frogans
   Player on a given Frogans site.  Frogans is a medium for publishing
   content and services on the Internet, defined as a generic software
   layer on the Internet.  Frogans Player is software that enables end
   users to browse Frogans sites.

Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for informational purposes.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It has been approved for publication by the Internet
   Engineering Steering Group (IESG).  Not all documents approved by the
   IESG are candidates for any level of Internet Standard; see Section 2
   of RFC 7841.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   https://www.rfc-editor.org/info/rfc8589.

Copyright Notice

   Copyright (c) 2019 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.




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Table of Contents

   1.  Background Information  . . . . . . . . . . . . . . . . . . .   2
     1.1.  About Frogans . . . . . . . . . . . . . . . . . . . . . .   2
     1.2.  About the OP3FT . . . . . . . . . . . . . . . . . . . . .   3
   2.  The Need for a New URI Scheme and Its Purpose . . . . . . . .   3
   3.  Choice of the Scheme Name . . . . . . . . . . . . . . . . . .   4
   4.  Scheme Syntax . . . . . . . . . . . . . . . . . . . . . . . .   5
     4.1.  URI Scheme  . . . . . . . . . . . . . . . . . . . . . . .   5
     4.2.  IRI Usage and Encoding  . . . . . . . . . . . . . . . . .   6
   5.  Trademarks  . . . . . . . . . . . . . . . . . . . . . . . . .   6
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   7
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .   7
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   8
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .   8
     8.2.  Informative References  . . . . . . . . . . . . . . . . .   8
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   9

1.  Background Information

1.1.  About Frogans

   Frogans is a medium for publishing content and services on the
   Internet.  From its inception in 1999, the medium was designed as a
   generic software layer running on top of the original Internet
   infrastructure (i.e., the TCP and IP protocols and the Domain Name
   System (DNS)), alongside other existing layers such as E-mail or the
   World Wide Web.

   As a medium, Frogans is not meant for publishing Web sites, but
   Frogans sites, a kind of site founded upon a different format,
   enabling a different kind of communication between end users and
   publishers of content and services.

   Frogans is intended to be complementary to the World Wide Web; it is
   not intended to be a replacement.  This is analogous to instant
   messaging, which was not intended to and did not replace E-mail.

   Compared to the World Wide Web, Frogans suggests publishing content
   and services that involve visual rather than text-based
   communication, focused content rather than long pages, and natural
   interaction rather than complex user interfaces.  For further
   information on the reasons for introducing Frogans on the Internet,
   and for an in-depth discussion of the similarities and differences
   between Frogans sites and Web sites, see [FSDL], Section 1.4
   ("Frogans sites and Web sites").





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   The technology making up the medium, i.e., the Frogans technology,
   includes multiple components such as:

   o  An XML-based language, called Frogans Slide Description Language
      [FSDL], used to develop Frogans sites.

   o  International identifiers, called Frogans addresses [IFAP], used
      to access Frogans sites.  Each Frogans site has its own Frogans
      address.

   o  Browsing software, called Frogans Player, enabling end users to
      browse Frogans sites.  An end user opens a Frogans site by
      entering its Frogans address in Frogans Player.

   o  A registry, called the Frogans Core Registry (FCR), that contains
      all Frogans addresses registered by Frogans site publishers.  The
      registry operator, called the FCR Operator, ensures the resolution
      of Frogans addresses when end users enter them in Frogans Player.

1.2.  About the OP3FT

   Created in 2012, the Organization for the Promotion, Protection, and
   Progress of Frogans Technology [OP3FT] is a dedicated, non-profit
   organization whose purpose is to hold, promote, protect, and ensure
   the progress of the Frogans technology, in the form of an open
   standard, available to all, free of charge.

   As part of its mission, the OP3FT develops and releases technical
   specifications, reference implementations (including Frogans Player),
   and various policies, which define the rights and responsibilities of
   all stakeholders involved in the technology worldwide.

2.  The Need for a New URI Scheme and Its Purpose

   Generic software layers running on top of the original Internet
   infrastructure offer mechanisms that enable end users to easily go
   from one layer to another, in both directions.  For example, end
   users can easily launch their usual Web browser on a given Web page
   from a message in their usual E-mail client; in the other direction,
   end users can easily launch their usual E-mail client with a given
   E-mail address from a Web page in their usual Web browser.  This is
   commonly achieved using URIs [RFC3986].

   As regards Frogans as a medium, in the outgoing direction, FSDL
   enables Frogans site publishers to include way-out buttons in their
   Frogans sites.  These buttons enable end users to launch their usual
   Web browser on a given Web page, or to launch their usual E-mail




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   client with a given E-mail address.  This is achieved by associating
   a URI with each of those way-out buttons (the scheme of the URI can
   be any of 'http', 'https', or 'mailto').

   Conversely, in the incoming direction, Web-site publishers should
   have a means to include in their Web pages links that enable end
   users to launch Frogans Player on a given Frogans site.  Likewise,
   people writing E-mail messages should have a means to include in
   their messages links that enable recipients to launch Frogans Player
   on a given Frogans site.  More generally, any end-user application
   should be able to launch Frogans Player on a given Frogans site.

   To achieve this, a new URI scheme, containing a Frogans address, is
   needed.

   Given that Frogans, as a medium, does not enable deep linking for
   Frogans sites, there is no need for additional information in the new
   URI scheme other than the Frogans address.

   The use of a media type as a means to include on a Web page a link
   that enables end users to launch Frogans Player on a given Frogans
   site was tested in 2006 with the registration of the
   'vnd.frogans.ltf' media type with IANA [LTF].  But use of a media
   type was determined to be unsatisfactory for several reasons.  First,
   for any such link included on a Web page, the author of the Web page
   had to create and host a .ltf file on the Web server hosting that Web
   page, which was cumbersome.  Furthermore, prior to creating such
   links, the author had to ask the server administrator to associate
   the .ltf files with the 'vnd.frogans.ltf' media type on the server.
   Alternatively, the author could create a link via a redirection
   service that would generate a .ltf file on the fly while associating
   it with the 'vnd.frogans.ltf' media type.  But that alternative
   raised privacy concerns and potentially added latency for end users.
   Finally, on the Web browser side, it appeared that using a media type
   from a Web page to launch another application did not always work,
   especially on mobile devices.

3.  Choice of the Scheme Name

   The name chosen for the new URI scheme is 'leaptofrogans'.

   This scheme name was chosen in compliance with [RFC7595], Section 3.8
   ("Scheme Name Considerations").








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   The following shorter names were discussed, but they were not chosen:

   o  'ltf': this name, an acronym for "leap to Frogans", was considered
      insufficiently descriptive, especially for typical end users who
      have little technical knowledge.

   o  'leapto': this name was considered overly general, and it is not
      specifically associated with Frogans.

   o  'frogans': this name was rejected because it could create
      confusion between URIs based on this scheme and those Frogans
      addresses that start with "frogans".

4.  Scheme Syntax

   Frogans addresses [IFAP] are international identifiers made up of
   Unicode characters.  Thus, a method for encoding non-US-ASCII
   characters is necessary when the new scheme is used as a URI.  The
   new scheme can also be useful as an IRI [RFC3987] in contexts where
   IRIs are allowed.

4.1.  URI Scheme

   The syntax for the 'leaptofrogans' URI scheme is:

      leaptofrogans-uri = "leaptofrogans:" pct-encoded-frogans-address

   where pct-encoded-frogans-address is a Frogans address compliant with
   [IFAP] and whose Unicode characters are each encoded as follows:

   o  If the character is a US-ASCII character, do not replace it and
      skip to the next character.  Note that according to [IFAP], the
      US-ASCII character cannot be the U+0025 PERCENT SIGN character.

   o  Otherwise, apply steps 1 through 3 below:

      1.  Convert the character to a sequence of one or more octets
          using UTF-8 [UTF-8]

      2.  Convert each octet to %HH, where HH is the hexadecimal
          notation of the octet value.  Note that this is identical to
          the percent-encoding mechanism in Section 2.1 of [RFC3986].

      3.  Replace the original character with the resulting character
          sequence (i.e., a sequence of %HH triplets).






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   Examples of 'leaptofrogans' URIs:

   -  if the Frogans address is the string of US-ASCII characters
      "Network-Name*Site-Name", the URI is as follows:

        leaptofrogans:Network-Name*Site-Name

   -  if the Frogans address is the string of Unicode characters U+7F51,
      U+7EDC, U+540D, U+002A, U+7AD9, U+540D (which is a Chinese
      translation of the Frogans address in the previous example), the
      URI is as follows:

        leaptofrogans:%E7%BD%91%E7%BB%9C%E5%90%8D*%E7%AB%99%E5%90%8D

4.2.  IRI Usage and Encoding

   The syntax for an IRI corresponding to the 'leaptofrogans' URI scheme
   is:

      leaptofrogans-iri = "leaptofrogans:" frogans-address

   where frogans-address is a Frogans address compliant with [IFAP] and
   encoded in UTF-8 [UTF-8].

   In contexts where both URIs and IRIs are allowed, end-user
   applications can use either a URI or an IRI based on the
   'leaptofrogans' URI scheme when launching Frogans Player on a given
   Frogans site.  This is because Frogans Player must interpret both
   URIs and IRIs based on the 'leaptofrogans' URI scheme.  If the U+0025
   PERCENT SIGN character is found in the string, then the string will
   be interpreted by Frogans Player as a URI; otherwise, it will be
   interpreted as an IRI.

5.  Trademarks

   In order to enable all users worldwide to use the Frogans technology
   in a clearly defined, secure, and perpetual environment, the OP3FT
   Bylaws [BYLAWS] provide for the implementation of an intellectual
   property policy.

   In this context, the OP3FT is the holder of the "Frogans" trademark
   that is registered in France, the United States, and other countries
   around the world.  The right to use the "Frogans" trademark in
   references or as part of initiatives in connection with the Frogans
   technology is granted in the OP3FT Trademark Usage Policy [OTUP].






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6.  IANA Considerations

   In accordance with the guidelines and registration procedures for new
   URI schemes [RFC7595], IANA has registered 'leaptofrogans' URI scheme
   as follows:

   Scheme name: 'leaptofrogans'

   Status: Permanent

   Scheme syntax: See Section 4 of RFC 8589.

   Scheme semantics: See Section 2 of RFC 8589.

   Encoding considerations: See Section 4 of RFC 8589.

   Applications/protocols that use this scheme name:  Frogans Player as
      well as any end-user application (such as a Web browser or an
      E-mail client) wishing to launch Frogans Player on a given Frogans
      site.

   Interoperability considerations:  There are no known interoperability
      concerns related to use of the 'leaptofrogans' URI scheme.

   Security considerations: See Section 7 of RFC 8589.

   Contact: Alexis Tamas <mailto:alexis.tamas@op3ft.org>

   Change controller: OP3FT <mailto:contact-standards@op3ft.org>

   References: RFC 8589

7.  Security Considerations

   The author of a Web page can create a link where the true nature of
   the URI is hidden in the link text that is visible to end users.  The
   same applies for an E-mail message and other end-user applications.

   For URIs based on the 'leaptofrogans' URI scheme, the risk of
   confusion is mitigated because Frogans Player must always display the
   real Frogans address contained in the URI, and it must always require
   confirmation by the end user before opening the corresponding Frogans
   site.

   Also, an end-user application may provide a URI containing a Frogans
   address that is not valid.  This does not represent a risk because,
   before asking for confirmation by the end user, Frogans Player must




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   always verify that the Frogans address contained in the URI is
   compliant with [IFAP], and it must always raise an error if the
   Frogans address is not compliant.

8.  References

8.1.  Normative References

   [IFAP]     OP3FT, "International Frogans Address Pattern",
              Version 1.1, ISBN 978-2-37313-000-3, November 2014,
              <https://www.frogans.org/en/resources/ifap/access.html>.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, DOI 10.17487/RFC3986, January 2005,
              <https://www.rfc-editor.org/info/rfc3986>.

   [RFC3987]  Duerst, M. and M. Suignard, "Internationalized Resource
              Identifiers (IRIs)", RFC 3987, DOI 10.17487/RFC3987,
              January 2005, <https://www.rfc-editor.org/info/rfc3987>.

   [RFC7595]  Thaler, D., Ed., Hansen, T., and T. Hardie, "Guidelines
              and Registration Procedures for URI Schemes", BCP 35,
              RFC 7595, DOI 10.17487/RFC7595, June 2015,
              <https://www.rfc-editor.org/info/rfc7595>.

   [UTF-8]    Yergeau, F., "UTF-8, a transformation format of ISO
              10646", STD 63, RFC 3629, DOI 10.17487/RFC3629, November
              2003, <https://www.rfc-editor.org/info/rfc3629>.

8.2.  Informative References

   [BYLAWS]   OP3FT, "Bylaws of the French Fonds de Dotation OP3FT,
              Organization for the Promotion, Protection and Progress of
              Frogans Technology", July 2016,
              <https://www.op3ft.org/en/resources/bylaws/access.html>.

   [FSDL]     OP3FT, "Frogans Slide Description Language", Version 3.0,
              Preliminary Draft 7, September 2018,
              <https://www.frogans.org/en/resources/fsdl/access.html>.

   [LTF]      IANA, "Media Types",
              <https://www.iana.org/assignments/media-types>.

   [OP3FT]    OP3FT, "Organization for the Promotion, Protection and
              Progress of Frogans Technology", <https://www.op3ft.org/>.





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   [OTUP]     OP3FT, "OP3FT Trademark Usage Policy", March 2017,
              <https://www.frogans.org/en/resources/otup/access.html>.

Authors' Addresses

   Alexis Tamas
   OP3FT
   6, Square Mozart
   75016 Paris
   France

   Phone: +33 1 53 92 00 40
   Email: alexis.tamas@op3ft.org


   Benjamin Phister (editor)
   OP3FT
   6, Square Mozart
   75016 Paris
   France

   Phone: +33 1 53 92 00 40
   Email: benjamin.phister@op3ft.org


   Jean-Emmanuel Rodriguez
   OP3FT
   6, Square Mozart
   75016 Paris
   France

   Phone: +33 1 53 92 00 40
   Email: jean-emmanuel.rodriguez@contrib.op3ft.org


















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