draft-ietf-iri-4395bis-irireg-01.txt   draft-ietf-iri-4395bis-irireg-02.txt 
Network Working Group T. Hansen Network Working Group T. Hansen
Internet-Draft AT&T Laboratories Internet-Draft AT&T Laboratories
Obsoletes: 4395 (if approved) T. Hardie Obsoletes: 4395 (if approved) T. Hardie
Intended status: BCP Panasonic Wireless Research Lab Intended status: BCP Panasonic Wireless Research Lab
Expires: September 30, 2011 L. Masinter Expires: January 29, 2012 L. Masinter
Adobe Adobe
March 29, 2011 July 28, 2011
Guidelines and Registration Procedures for New URI/IRI Schemes Guidelines and Registration Procedures for New URI/IRI Schemes
draft-ietf-iri-4395bis-irireg-01 draft-ietf-iri-4395bis-irireg-02
Abstract Abstract
This document updates the guidelines and recommendations for the This document updates the guidelines and recommendations for the
definition of Uniform Resource Identifier (URI) schemes, and extends definition of Uniform Resource Identifier (URI) schemes, and extends
the registry and guidelines to apply when the schemes are used with the registry and guidelines to apply when the schemes are used with
Internationalized Resource Identifiers (IRIs). It also updates the Internationalized Resource Identifiers (IRIs). It also updates the
process and IANA registry for URI/IRI schemes. It obsoletes RFC process and IANA registry for URI/IRI schemes. It obsoletes RFC
4395. 4395.
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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 http://datatracker.ietf.org/drafts/current/. Drafts is at http://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 30, 2011. This Internet-Draft will expire on January 29, 2012.
Copyright Notice Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the Copyright (c) 2011 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
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
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to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conformance Guidelines . . . . . . . . . . . . . . . . . . . . 4 2. Conformance Guidelines . . . . . . . . . . . . . . . . . . . . 4
3. Guidelines for Permanent URI/IRI Scheme Definitions . . . . . 4 3. Guidelines for Permanent URI/IRI Scheme Definitions . . . . . 4
3.1. Demonstratable, New, Long-Lived Utility . . . . . . . . . 5 3.1. Demonstratable, New, Long-Lived Utility . . . . . . . . . 4
3.2. Syntactic Compatibility . . . . . . . . . . . . . . . . . 5 3.2. Syntactic Compatibility . . . . . . . . . . . . . . . . . 5
3.3. Well-Defined . . . . . . . . . . . . . . . . . . . . . . . 6 3.3. Well-Defined . . . . . . . . . . . . . . . . . . . . . . . 5
3.4. Definition of Operations . . . . . . . . . . . . . . . . . 6 3.4. Definition of Operations . . . . . . . . . . . . . . . . . 6
3.5. Context of Use . . . . . . . . . . . . . . . . . . . . . . 7 3.5. Context of Use . . . . . . . . . . . . . . . . . . . . . . 6
3.6. Internationalization and Character Encoding . . . . . . . 7 3.6. Internationalization and Character Encoding . . . . . . . 7
3.7. Clear Security Considerations . . . . . . . . . . . . . . 7 3.7. Clear Security Considerations . . . . . . . . . . . . . . 7
3.8. Scheme Name Considerations . . . . . . . . . . . . . . . . 8 3.8. Scheme Name Considerations . . . . . . . . . . . . . . . . 8
4. Guidelines for Provisional URI/IRI Scheme Registration . . . . 8 4. Guidelines for Provisional URI/IRI Scheme Registration . . . . 8
5. Guidelines for Historical URI/IRI Scheme Registration . . . . 9 5. Guidelines for Historical URI/IRI Scheme Registration . . . . 9
6. URI/IRI Scheme Registration Procedure . . . . . . . . . . . . 9 6. URI/IRI Scheme Registration Procedure . . . . . . . . . . . . 9
6.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 9 6.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 9
6.2. Registration Procedures . . . . . . . . . . . . . . . . . 10 6.2. Registration Procedures . . . . . . . . . . . . . . . . . 10
6.3. Change Control . . . . . . . . . . . . . . . . . . . . . . 11 6.3. Change Control . . . . . . . . . . . . . . . . . . . . . . 11
6.4. URI/IRI Scheme Registration Template . . . . . . . . . . . 11 6.4. URI/IRI Scheme Registration Template . . . . . . . . . . . 11
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11.2. Informative References . . . . . . . . . . . . . . . . . . 15 11.2. Informative References . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction 1. Introduction
The Uniform Resource Identifier (URI) protocol element and generic The Uniform Resource Identifier (URI) protocol element and generic
syntax is defined by [RFC3986]. Each URI begins with a scheme name, syntax is defined by [RFC3986]. Each URI begins with a scheme name,
as defined by Section 3.1 of RFC 3986, that refers to a specification as defined by Section 3.1 of RFC 3986, that refers to a specification
for identifiers within that scheme. The URI syntax provides a for identifiers within that scheme. The URI syntax provides a
federated and extensible naming system, where each scheme's federated and extensible naming system, where each scheme's
specification may further restrict the syntax and semantics of specification may further restrict the syntax and define the
identifiers using that scheme. As originally defined, URIs only semantics of identifiers using that scheme. As originally defined,
allowed a limited repertoire of characters chosen from US-ASCII. An URIs only allowed a limited repertoire of characters chosen from US-
Interationalized Resource Identifier (IRI) as defined by ASCII.
An Interationalized Resource Identifier (IRI), as defined by
[RFC3987bis], extends the URI syntax to allow characters from a much [RFC3987bis], extends the URI syntax to allow characters from a much
greater repertoire, to accomodate resource identifiers from the greater repertoire, to accomodate resource identifiers from the
world's languages. The same schemes used in URIs are used in IRIs. world's languages. The same schemes used in URIs are used in IRIs.
The term Resource Identifier (RI) is used as a shorthand for both The term Resource Identifier (RI) is used as a shorthand for both
URIs and IRIs. URIs and IRIs. [RFC3987] introduced IRIs by defining a mapping
between URIs and IRIs; [RFC3987bis] updates that definition, allowing
an IRI to be interpreted directly without translating into a URI.
This document obsoletes [RFC4395], which in turn obsoleted [RFC2717]
and [RFC2718]. Recent documents have used the terms "URI"/"IRI" for
all resource identifiers, avoiding the term "URL" and reserving the
term "URN" explicitly for those URIs/IRIs using the "urn" scheme name
([RFC2141]). URN "namespaces" ([RFC3406]) are specific to the "urn"
scheme and are not covered explicitly by this specification.
This document extends the URI scheme registry to be a registry of This document extends the URI scheme registry to be a registry of
URI/IRI schemes (i.e., applicable to both URIs and IRIs). This URI/IRI schemes (i.e., applicable to both URIs and IRIs). This
document also provides updated guidelines for the definition of new document also provides updated guidelines for the definition of new
schemes, for consideration by those who are defining, registering, or schemes, for consideration by those who are defining, registering, or
evaluating those definitions, as well as a process and mechanism for evaluating those definitions, as well as a process and mechanism for
registering URI/IRI schemes within the IANA URI scheme registry. The registering URI/IRI schemes within the IANA URI scheme registry.
registry has two parts: 'provisional' and 'permanent', with different There is a single namespace for registered schemes. Within that
requirements. Guidelines and requirements for both parts are given. namespace, there are values that are approved as meeting a set of
criteria for permanent URI/IRI schemes. Other scheme names may also
This document obsoletes [RFC4395], which in turn obsoleted [RFC2717] be registered provisionally or historically, without necessarily
and [RFC2718]. RFCs 2717 and 2718 drew a distinction between meeting those criteria. The intent of the registry is to:
'locators' (identifiers used for accessing resources available on the
Internet) and 'names' (identifiers used for naming possibly abstract
resources, independent of any mechanism for accessing them). The
intent was to use the designation "URL" (Uniform Resource Locator)
for those identifiers that were locators and "URN" (Uniform Resource
Name) for those identifiers that were names. In practice, the line
between 'locator' and 'name' has been difficult to draw: locators can
be used as names, and names can be used as locators. As a result,
recent documents have used the terms "URI"/"IRI" for all resource
identifiers, avoiding the term "URL" and reserving the term "URN"
explicitly for those URIs/IRIs using the "urn" scheme name
([RFC2141]). URN "namespaces" ([RFC3406]) are specific to the "urn"
scheme and not covered explicitly by this specification.
RFC 2717 defined a set of registration trees in which URI schemes
could be registered, one of which was called the IETF Tree, to be
managed by IANA. RFC 2717 proposed that additional registration
trees might be approved by the IESG. However, no such registration
trees have been submitted. This document eliminates RFC 2717's
distinction between different 'trees' for URI schemes; instead there
is a single namespace for registered values. Within that namespace,
there are values that are approved as meeting a set of criteria for
URI schemes. Other scheme names may also be registered
provisionally, without necessarily meeting those criteria. The
intent of the registry is to:
o provide a central point of discovery for established URI/IRI o provide a central point of discovery for established URI/IRI
scheme names, and easy location of their defining documents; scheme names, and easy location of their defining documents;
o discourage use of the same scheme name for different purposes; o discourage use of the same scheme name for different purposes;
o help those proposing new scheme names to discern established o help those proposing new scheme names to discern established
trends and conventions, and avoid names that might be confused trends and conventions, and avoid names that might be confused
with existing ones; with existing ones;
o encourage registration by setting a low barrier for provisional o encourage registration by setting a low barrier for provisional
registrations. registrations.
[RFC3987] introduced a new protocol element, the Internationalized There is no separate, independent registry or registration process
Resource Identifier (IRI), by defining a mapping between URIs and for IRIs: the URI Scheme Registry is to be used for both URIs and
IRIs. [RFC3987bis] updates this definition, allowing an IRI to be IRIs. Previously, those who wish to describe resource identifiers
interpreted directly without translating into a URI. There is no that are useful as IRIs were encouraged to define the corresponding
separate, independent registry or registration process for IRIs: the URI syntax, and note that the IRI usage follows the rules and
URI Scheme Registry is to be used for both URIs and IRIs.
Previously, those who wish to describe resource identifiers that are
useful as IRIs were encouraged to define the corresponding URI
syntax, and note that the IRI usage follows the rules and
transformations defined in [RFC3987]. This document changes that transformations defined in [RFC3987]. This document changes that
advice to encourage explicit definition of the scheme and allowable advice to encourage explicit definition of the scheme and allowable
syntax elements within the larger character repertoire of IRIs, as syntax elements within the larger character repertoire of IRIs, as
defined by [RFC3987bis]. defined by [RFC3987bis].
A scheme definition cannot override the orverall syntax for IRIs.
For example, this means that fragment identifiers (#) cannot be re-
used outside the generic syntax restrictions, and in particular
scheme-specific syntax cannot override the fragment identifier syntax
because it is generic.
2. Conformance Guidelines 2. Conformance Guidelines
Within this document, the key words MUST, MAY, SHOULD, REQUIRED, Within this document, the key words MUST, MAY, SHOULD, REQUIRED,
RECOMMENDED, and so forth are used within the general meanings RECOMMENDED, and so forth are used within the general meanings
established in [RFC2119], within the context that they are established in [RFC2119], within the context that they are
requirements on future registration specifications. requirements on future registration specifications.
3. Guidelines for Permanent URI/IRI Scheme Definitions 3. Guidelines for Permanent URI/IRI Scheme Definitions
This section gives considerations for new URI/IRI schemes. Meeting This section gives considerations for new URI/IRI schemes. Meeting
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compatibility issues with IRIs of the scheme. compatibility issues with IRIs of the scheme.
Specifications for IRIs schemes MUST be described in terms of Specifications for IRIs schemes MUST be described in terms of
processing an IRI as a sequence of Unicode codepoints, without processing an IRI as a sequence of Unicode codepoints, without
reference to the encoding of those code points as a sequence of reference to the encoding of those code points as a sequence of
bytes, using UTF-8 or UTF-16. The scheme specification SHOULD be as bytes, using UTF-8 or UTF-16. The scheme specification SHOULD be as
restrictive as possible regarding what characters are allowed in the restrictive as possible regarding what characters are allowed in the
URI/IRI, because some characters can create several different URI/IRI, because some characters can create several different
security considerations (see for example [RFC4690]). security considerations (see for example [RFC4690]).
If an IRI scheme has specific length limitations, they MUST be
specified in terms of Unicode codepoints and not in terms of octets
(in any particular encoding).
All percent-encoded variants are automatically included by definition
for any character given in an IRI production. This means that if you
want to restrict the URI percent-encoded forms in some way, you must
restrict the Unicode forms that would lead to them.
3.7. Clear Security Considerations 3.7. Clear Security Considerations
Definitions of schemes MUST be accompanied by a clear analysis of the Definitions of schemes MUST be accompanied by a clear analysis of the
security implications for systems that use the scheme; this follows security implications for systems that use the scheme; this follows
the practice of Security Consideration sections within IANA the practice of Security Consideration sections within IANA
registrations [RFC5226]. registrations [RFC5226].
In particular, Section 7 of RFC 3986 [RFC3986] describes general In particular, Section 7 of RFC 3986 [RFC3986] describes general
security considerations for URIs, while Section ??? of [RFC3987bis] security considerations for URIs, while Section ??? of [RFC3987bis]
gives those for IRIs. The definition of an individual URI/IRI scheme gives those for IRIs. The definition of an individual URI/IRI scheme
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Provisional registration can be an intermediate step on the way to Provisional registration can be an intermediate step on the way to
permanent registration, e.g., before the scheme specification is permanent registration, e.g., before the scheme specification is
finalized. Provisional registration is also appropriate for schemes finalized. Provisional registration is also appropriate for schemes
that are known to be used, but where a definitive specification is that are known to be used, but where a definitive specification is
not available. There is no time limit for provisional registration. not available. There is no time limit for provisional registration.
While the guidelines in Section 3 are REQUIRED for permanent While the guidelines in Section 3 are REQUIRED for permanent
registration, they are RECOMMENDED for provisional registration. For registration, they are RECOMMENDED for provisional registration. For
a provisional registration, the following are REQUIRED: a provisional registration, the following are REQUIRED:
o The scheme name meets the syntactic requirements of Section 3.8. o The scheme name meets the syntactic requirements of Section 3.8
and the encoding requirements of Section 3.6.
o There is not already an entry with the same scheme name. (In the o There is not already an entry with the same scheme name. (In the
unfortunate case that there are multiple, different uses of the unfortunate case that there are multiple, different uses of the
same scheme name, the IESG may approve a request to modify an same scheme name, the IESG may approve a request to modify an
existing entry to note the separate use.) existing entry to note the separate use.)
o Contact information identifying the person supplying the o Contact information identifying the person supplying the
registration is included. Previously unregistered schemes registration is included. Previously unregistered schemes
discovered in use may be registered by third parties (even if not discovered in use may be registered by third parties (even if not
on behalf of those who created the scheme). In this case, both on behalf of those who created the scheme). In this case, both
the registering party and the scheme creator SHOULD be identified. the registering party and the scheme creator SHOULD be identified.
o If no permanent, citable specification for the scheme definition o If no permanent, citable specification for the scheme definition
is included, credible reasons for not providing it should be is included, credible reasons for not providing it should be
given. given.
o A valid Security Considerations section, as required by Section 6 o A valid Security Considerations section, as required by Section 6
of [RFC5226]. of [RFC5226].
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In exceptional cases, where the negotiating parties cannot form a In exceptional cases, where the negotiating parties cannot form a
consensus, the final arbiter of any contested registration shall be consensus, the final arbiter of any contested registration shall be
the IESG. the IESG.
If parties achieve consensus on a registration proposal that does not If parties achieve consensus on a registration proposal that does not
fully conform to the strict wording of this procedure, this should be fully conform to the strict wording of this procedure, this should be
drawn to the attention of a relevant member of the IESG. drawn to the attention of a relevant member of the IESG.
6.2. Registration Procedures 6.2. Registration Procedures
Someone wishing to register a new URI/IRI scheme SHOULD: Someone wishing to register a new URI/IRI scheme MUST:
1. Check the IANA URI scheme registry to see whether or not there is 1. Check the IANA URI scheme registry to see whether or not there is
already an entry for the desired name. If there is already an already an entry for the desired name. If there is already an
entry under the name, choose a different URI scheme name, or entry under the name, choose a different URI scheme name, or
update the existing scheme definition. update the existing scheme definition.
2. Prepare a URI/IRI scheme registration template, as specified in 2. Prepare a URI/IRI scheme registration template, as specified in
Section 6.4. The scheme registration template may be contained Section 6.4. The scheme registration template may be contained
in an Internet Draft, submitted alone, or as part of some other in an Internet Draft, submitted alone, or as part of some other
permanently available, stable, protocol specification. The permanently available, stable, protocol specification. The
template may also be submitted in some other form (as part of template may also be submitted in some other form (as part of
another document or as a stand-alone document), but the contents another document or as a stand-alone document), but the contents
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Transition from 'permanent' to 'historical' status requires IESG Transition from 'permanent' to 'historical' status requires IESG
approval. Transition from 'provisional' to 'historical' may be approval. Transition from 'provisional' to 'historical' may be
requested by anyone authorized to update the provisional requested by anyone authorized to update the provisional
registration. registration.
6.4. URI/IRI Scheme Registration Template 6.4. URI/IRI Scheme Registration Template
This template describes the fields that must be supplied in a URI/IRI This template describes the fields that must be supplied in a URI/IRI
scheme registration request: scheme registration request:
Resource Identifier (RI) Scheme name. Resource Identifier (RI) Scheme name:
See Section 3.8 for guidelines. See Section 3.8 for guidelines.
Status. Status:
This reflects the status requested, and should be one of This reflects the status requested, and should be one of
'permanent', 'provisional', or 'historical'. 'permanent', 'provisional', or 'historical'.
Scheme syntax. Scheme syntax:
See Section 3.2 for guidelines. See Section 3.2 for guidelines.
Scheme semantics. Scheme semantics:
See Section 3.3 and Section 3.4 for guidelines. See Section 3.3 and Section 3.4 for guidelines.
Encoding considerations. Encoding considerations:
See Section 3.3 and Section 3.6 for guidelines. See Section 3.3 and Section 3.6 for guidelines.
Applications/protocols that use this scheme name. Applications/protocols that use this scheme name:
See Section 3.5. See Section 3.5.
Interoperability considerations. Interoperability considerations:
If the person or group registering the scheme is aware of any If the person or group registering the scheme is aware of any
details regarding the scheme that might impact interoperability, details regarding the scheme that might impact interoperability,
identify them here. For example: proprietary or uncommon encoding identify them here. For example: proprietary or uncommon encoding
methods; inability to support multibyte character sets; methods; inability to support multibyte character sets;
incompatibility with types or versions of any underlying protocol. incompatibility with types or versions of any underlying protocol.
Security considerations. Security considerations:
See Section 3.7 for guidelines. See Section 3.7 for guidelines.
Contact. Contact:
Person (including contact information) to contact for further Person (including contact information) to contact for further
information. information.
Author/Change controller. Author/Change controller:
Person (including contact information) authorized to change this, Person (including contact information) authorized to change this,
if a provisional registration. if a provisional registration.
References. References:
Include full citations for all referenced documents. Registration Include full citations for all referenced documents. Registration
templates for provisional registration may be included in an templates for provisional registration may be included in an
Internet Draft; when the documents expire or are approved for Internet Draft; when the documents expire or are approved for
publication as an RFC, the registration will be updated. publication as an RFC, the registration will be updated.
7. The "example" Scheme 7. The "example" Scheme
There is a need for a URI/IRI Scheme name that can be used for There is a need for a URI/IRI Scheme name that can be used for
examples in documentation without fear of conflicts with current or examples in documentation without fear of conflicts with current or
future actual schemes. The URI/IRI Scheme "example" is hereby future actual schemes. The URI/IRI Scheme "example" is hereby
registered as a Permanent URI/IRI Scheme for that purpose. registered as a Permanent URI/IRI Scheme for that purpose.
Scheme name example Scheme name: example
Status permanent Status: permanent
Scheme syntax The entire range of allowable syntax for URI/IRI Scheme syntax: The entire range of allowable syntax for URI/IRI
schemes specified in [RFC3987bis] is allowed for "example" URI/ schemes specified in [RFC3987bis] is allowed for "example" URI/
IRIs. IRIs.
Scheme semantics URI/IRIs in the "example" scheme should be used for Scheme semantics: URI/IRIs in the "example" scheme should be used
documentation purposes only. The use of "example" URIs/IRIs must for documentation purposes only. The use of "example" URIs/IRIs
not be used as locators, identify any resources, or specify any must not be used as locators, identify any resources, or specify
particular set of operations. any particular set of operations.
Encoding considerations See Section 2.5 of [RFC3986] for guidelines. Encoding considerations: See Section 2.5 of [RFC3986] for
Applications/protocols that use this URI scheme name The "example" guidelines.
Applications/protocols that use this URI scheme name: The "example"
URI should be used for documentation purposes only. It MUST not URI should be used for documentation purposes only. It MUST not
be used for any protocol. be used for any protocol.
Interoperability considerations None. Interoperability considerations: None.
Security considerations None. Security considerations: None.
Contact N/A Contact: N/A
Author/Change controller IETF Author/Change controller: IETF
References This RFC XXXX. References: This RFC XXXX.
RFC Editor Note: Replace XXXX with this RFC's reference. RFC Editor Note: Replace XXXX with this RFC's reference.
8. IANA Considerations 8. IANA Considerations
Previously, the former "URL Scheme" registry was replaced by the Previously, the former "URL Scheme" registry was replaced by the
Uniform Resource Identifier scheme registry. The process was based Uniform Resource Identifier scheme registry. The process was based
on [RFC5226] "Expert Review" with an initial (optional) mailing list on [RFC5226] "Expert Review" with an initial (optional) mailing list
review. review.
The updated template has an additional field for the status of the The updated template has an additional field for the status of the
scheme, and the procedures for entering new name schemes have been scheme, and the procedures for entering new name schemes have been
augmented. Section 6 establishes the process for new URI/IRI scheme augmented. Section 6 establishes the process for new URI/IRI scheme
registration. registration.
IANA is requested to update the name of the registry "URI Schemes" to
"URI/IRI Schemes". The registry should be updated to point to this
document. For the tables within that registry "Permanent URI
Schemes" should become "Permanent URI/IRI Schemes", "Provisional URI
Schemes" should become "Provisional URI/IRI Schemes", and "Historical
URI Schemes" should become "Historical URI/IRI Schemes".
The example URI scheme "example" is hereby registered. (See the The example URI scheme "example" is hereby registered. (See the
template above for registration.) template above for registration.)
9. Security Considerations 9. Security Considerations
All registered values are expected to contain accurate security All registered values are expected to contain accurate security
consideration sections; 'permanent' registered scheme names are consideration sections; 'permanent' registered scheme names are
expected to contain complete definitions. expected to contain complete definitions.
Information concerning possible security vulnerabilities of a Information concerning possible security vulnerabilities of a
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