< draft-ietf-6man-rfc6874bis-00.txt   draft-ietf-6man-rfc6874bis-01.txt >
6MAN B. Carpenter 6MAN B. Carpenter
Internet-Draft Univ. of Auckland Internet-Draft Univ. of Auckland
Obsoletes: 6874 (if approved) S. Cheshire Obsoletes: 6874 (if approved) S. Cheshire
Updates: 3986, 3987 (if approved) Apple Inc. Updates: 3986, 3987 (if approved) Apple Inc.
Intended status: Standards Track R. Hinden Intended status: Standards Track R. Hinden
Expires: 19 September 2022 Check Point Software Expires: 7 October 2022 Check Point Software
18 March 2022 5 April 2022
Representing IPv6 Zone Identifiers in Address Literals and Uniform Representing IPv6 Zone Identifiers in Address Literals and Uniform
Resource Identifiers Resource Identifiers
draft-ietf-6man-rfc6874bis-00 draft-ietf-6man-rfc6874bis-01
Abstract Abstract
This document describes how the zone identifier of an IPv6 scoped This document describes how the zone identifier of an IPv6 scoped
address, defined as <zone_id> in the IPv6 Scoped Address Architecture address, defined as <zone_id> in the IPv6 Scoped Address Architecture
(RFC 4007), can be represented in a literal IPv6 address and in a (RFC 4007), can be represented in a literal IPv6 address and in a
Uniform Resource Identifier that includes such a literal address. It Uniform Resource Identifier that includes such a literal address. It
updates the URI Generic Syntax and Internationalized Resource updates the URI Generic Syntax and Internationalized Resource
Identifier specifications (RFC 3986, RFC 3987) accordingly, and Identifier specifications (RFC 3986, RFC 3987) accordingly, and
obsoletes RFC 6874. obsoletes RFC 6874.
skipping to change at page 1, line 49 skipping to change at page 1, line 49
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on 19 September 2022. This Internet-Draft will expire on 7 October 2022.
Copyright Notice Copyright Notice
Copyright (c) 2022 IETF Trust and the persons identified as the Copyright (c) 2022 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 (https://trustee.ietf.org/ Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document. license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as extracted from this document must include Revised BSD License text as
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provided without warranty as described in the Revised BSD License. provided without warranty as described in the Revised BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Issues with Implementing RFC 6874 . . . . . . . . . . . . . . 4 2. Issues with Implementing RFC 6874 . . . . . . . . . . . . . . 4
3. Specification . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Specification . . . . . . . . . . . . . . . . . . . . . . . . 5
4. URI Parsers . . . . . . . . . . . . . . . . . . . . . . . . . 6 4. URI Parsers . . . . . . . . . . . . . . . . . . . . . . . . . 6
5. Security Considerations . . . . . . . . . . . . . . . . . . . 7 5. Security Considerations . . . . . . . . . . . . . . . . . . . 7
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 7 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
7.1. Normative References . . . . . . . . . . . . . . . . . . 7 7.1. Normative References . . . . . . . . . . . . . . . . . . 8
7.2. Informative References . . . . . . . . . . . . . . . . . 8 7.2. Informative References . . . . . . . . . . . . . . . . . 9
Appendix A. Options Considered . . . . . . . . . . . . . . . . . 9 Appendix A. Options Considered . . . . . . . . . . . . . . . . . 10
Appendix B. Change log . . . . . . . . . . . . . . . . . . . . . 10 Appendix B. Change log . . . . . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12
1. Introduction 1. Introduction
The Uniform Resource Identifier (URI) syntax specification [RFC3986] The Uniform Resource Identifier (URI) syntax specification [RFC3986]
defined how a literal IPv6 address can be represented in the "host" defined how a literal IPv6 address can be represented in the "host"
part of a URI. Two months later, the IPv6 Scoped Address part of a URI. Two months later, the IPv6 Scoped Address
Architecture specification [RFC4007] extended the text representation Architecture specification [RFC4007] extended the text representation
of limited-scope IPv6 addresses such that a zone identifier may be of limited-scope IPv6 addresses such that a zone identifier may be
concatenated to a literal address, for purposes described in that concatenated to a literal address, for purposes described in that
specification. Zone identifiers are especially useful in contexts in specification. Zone identifiers are especially useful in contexts in
which literal addresses are typically used, for example, during fault which literal addresses are typically used, for example, during fault
diagnosis, when it may be essential to specify which interface is diagnosis, when it may be essential to specify which interface is
used for sending to a link-local address. It should be noted that used for sending to a link-local address. It should be noted that
zone identifiers have purely local meaning within the node in which zone identifiers have purely local meaning within the node in which
they are defined, often being the same as IPv6 interface names. They they are defined, usually being the same as IPv6 interface names.
are completely meaningless for any other node. Today, they are They are completely meaningless for any other node. Today, they are
meaningful only when attached to addresses with less than global meaningful only when attached to link-local addresses, but it is
scope, but it is possible that other uses might be defined in the possible that other uses might be defined in the future.
future.
The IPv6 Scoped Address Architecture specification [RFC4007] does not The IPv6 Scoped Address Architecture specification [RFC4007] does not
specify how zone identifiers are to be represented in URIs. specify how zone identifiers are to be represented in URIs.
Practical experience has shown that this feature is useful or Practical experience has shown that this feature is useful or
necessary, in at least three use cases: necessary, in multiple use cases:
1. When using a web browser for simple debugging actions involving 1. A web browser may be used for simple debugging actions involving
link-local addresses on a host with more than one active link link-local addresses on a host with more than one active link
interface. interface.
2. When using a web browser to configure or reconfigure a device 2. A web browser must sometimes be used to configure or reconfigure
which only has a link local address and whose only configuration a device which only has a link local address and whose only
tool is a web server, again from a host with more than one active configuration tool is a web server, again in a host with more
link interface. than one active link interface.
3. When using an HTTP-based protocol for establishing link-local 3. The Apple and open-source CUPS printing mechanism [CUPS]
relationships, such as the Apple CUPS printing mechanism [CUPS]. [OP-CUPS] uses an HTTP-based protocol [RFC3510][RFC7472] to
establish link-local relationships, so requires the specification
of the relevant interface.
4. The Microsoft Web Services for Devices (WSD) virtual printer port
mechanism can generate an IPv6 Link Local URL in which the zone
identifier is present and necessary, but is not recognized by any
current browser.
It should be noted that whereas some operating systems and network It should be noted that whereas some operating systems and network
APIs support a default zone identifier as described in [RFC4007], APIs support a default zone identifier as described in [RFC4007],
others do not, and for them an appropriate URI syntax is particularly others do not, and for them an appropriate URI syntax is particularly
important. important.
In the past, some browser versions directly accepted the IPv6 Scoped In the past, some browser versions directly accepted the IPv6 Scoped
Address syntax [RFC4007] for scoped IPv6 addresses embedded in URIs, Address syntax [RFC4007] for scoped IPv6 addresses embedded in URIs,
i.e., they were coded to interpret a "%" sign following the literal i.e., they were coded to interpret a "%" sign following the literal
address as introducing a zone identifier [RFC4007], instead of address as introducing a zone identifier [RFC4007], instead of
introducing two hexadecimal characters representing some percent- introducing two hexadecimal characters representing some percent-
encoded octet [RFC3986]. Clearly, interpreting the "%" sign as encoded octet [RFC3986]. Clearly, interpreting the "%" sign as
introducing a zone identifier is very convenient for users, although introducing a zone identifier is very convenient for users, although
it is not supported by the URI syntax [RFC3986] or the it is not supported by the URI syntax in [RFC3986] or the
Internationalized Resource Identifier (IRI) syntax [RFC3987]. Internationalized Resource Identifier (IRI) syntax in [RFC3987].
Therefore, this document updates RFC 3986 and RFC 3987 by adding Therefore, this document updates RFC 3986 and RFC 3987 by adding
syntax to allow a zone identifier to be included in a literal IPv6 syntax to allow a zone identifier to be included in a literal IPv6
address within a URI. address within a URI.
It should be noted that in contexts other than a user interface, a It should be noted that in contexts other than a user interface, a
zone identifier is mapped into a numeric zone index or interface zone identifier is mapped into a numeric zone index or interface
number. The MIB textual convention InetZoneIndex [RFC4001] and the number. The MIB textual convention InetZoneIndex [RFC4001] and the
socket interface [RFC3493] define this as a 32-bit unsigned integer. socket interface [RFC3493] define this as a 32-bit unsigned integer.
The mapping between the human-readable zone identifier string and the The mapping between the human-readable zone identifier string and the
numeric value is a host-specific function that varies between numeric value is a host-specific function that varies between
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3. Specification 3. Specification
According to IPv6 Scoped Address syntax [RFC4007], a zone identifier According to IPv6 Scoped Address syntax [RFC4007], a zone identifier
is attached to the textual representation of an IPv6 address by is attached to the textual representation of an IPv6 address by
concatenating "%" followed by <zone_id>, where <zone_id> is a string concatenating "%" followed by <zone_id>, where <zone_id> is a string
identifying the zone of the address. However, the IPv6 Scoped identifying the zone of the address. However, the IPv6 Scoped
Address Architecture specification gives no precise definition of the Address Architecture specification gives no precise definition of the
character set allowed in <zone_id>. There are no rules or de facto character set allowed in <zone_id>. There are no rules or de facto
standards for this. For example, the first Ethernet interface in a standards for this. For example, the first Ethernet interface in a
host might be called %0, %1, %en1, %eth0, or whatever the implementer host might be called %0, %1, %25, %en1, %eth0, or whatever the
happened to choose. Also, %25 would be valid. implementer happened to choose.
In a URI, a literal IPv6 address is always embedded between "[" and In a URI, a literal IPv6 address is always embedded between "[" and
"]". This document specifies how a <zone_id> can be appended to the "]". This document specifies how a zone identifier can be appended
address. According to the text in Section 2.4 of [RFC3986], "%" must to the address. The URI syntax defined by [RFC3986] does not allow
be percent-encoded as "%25" to be used as data within a URI. the presence of a percent ("%") character within an IPv6 address
However, in the formal ABNF syntax of RFC 3986, this only applies literal. For this reason, it is backwards compatible to allow the
where the "pct-encoded" element appears. For this reason, it is use of "%" within an IPv6 address literal as a delimiter only, such
possible to extend the ABNF such that the scoped address that the scoped address fe80::abcd%en1 would appear in a URI as
fe80::abcd%en1 would appear in a URI as http://[fe80::abcd%en1] or http://[fe80::abcd%en1] or https://[fe80::abcd%en1].
https://[fe80::abcd%en1].
A <zone_id> MUST contain only ASCII characters classified as This use of "%" as a delimiter applies only within an IPv6 address
literal, and is irrelevant to and exempt from the percent-encoding
mechanism [RFC3986].
A zone identifier MUST contain only ASCII characters classified as
"unreserved" for use in URIs [RFC3986]. This excludes characters "unreserved" for use in URIs [RFC3986]. This excludes characters
such as "]" or even "%" that would complicate parsing. The <zone_id> such as "]" or even "%" that would complicate parsing. For the
"25" cannot be forbidden since it is valid in some operating systems, avoidance of doubt, note that a zone identifier consisting of "25" or
so a parser MUST NOT apply percent decoding to a URI such as starting with "25" is valid and is used in some operating systems. A
http://[fe80::abcd%25]. parser MUST NOT apply percent decoding to the IPv6 address literal in
a URI, including cases such as http://[fe80::abcd%25] and
http://[fe80::abcd%25xy].
If an operating system uses any other characters in zone or interface If an operating system uses any other characters in zone or interface
identifiers that are not in the "unreserved" character set, they identifiers that are not in the "unreserved" character set, they
cannot be used in a URI. cannot be used in a URI.
We now present the corresponding formal syntax. We now present the corresponding formal syntax.
The URI syntax specification [RFC3986] formally defines the IPv6 The URI syntax specification [RFC3986] formally defines the IPv6
literal format in ABNF [RFC5234] by the following rule: literal format in ABNF [RFC5234] by the following rule:
skipping to change at page 6, line 7 skipping to change at page 6, line 29
This syntax fills the gap that is described at the end of This syntax fills the gap that is described at the end of
Section 11.7 of the IPv6 Scoped Address Architecture specification Section 11.7 of the IPv6 Scoped Address Architecture specification
[RFC4007]. It replaces and obsoletes the syntax in Section 2 of [RFC4007]. It replaces and obsoletes the syntax in Section 2 of
[RFC6874]. [RFC6874].
The established rules for textual representation of IPv6 addresses The established rules for textual representation of IPv6 addresses
[RFC5952] SHOULD be applied in producing URIs. [RFC5952] SHOULD be applied in producing URIs.
The URI syntax specification [RFC3986] states that URIs have a global The URI syntax specification [RFC3986] states that URIs have a global
scope, but that in some cases their interpretation depends on the scope, but that in some cases their interpretation depends on the
end-user's context. URIs including a ZoneID are to be interpreted end-user's context. URIs including a zone identifier are to be
only in the context of the host at which they originate, since the interpreted only in the context of the host at which they originate,
ZoneID is of local significance only. since the zone identifier is of local significance only.
The IPv6 Scoped Address Architecture specification [RFC4007] offers The IPv6 Scoped Address Architecture specification [RFC4007] offers
guidance on how the ZoneID affects interface/address selection inside guidance on how the zone identifier affects interface/address
the IPv6 stack. Note that the behaviour of an IPv6 stack, if it is selection inside the IPv6 stack. Note that the behaviour of an IPv6
passed a non-null zone index for an address other than link-local, is stack, if it is passed a non-null zone index for an address other
undefined. than link-local, is undefined.
In cases where the RFC 6874 encoding is currently used between
specific software components rather than between a browser and a web
server, such usage MAY continue indefinitely.
4. URI Parsers 4. URI Parsers
This section discusses how URI parsers, such as those embedded in web This section discusses how URI parsers, such as those embedded in web
browsers, might handle this syntax extension. Unfortunately, there browsers, might handle this syntax extension. Unfortunately, there
is no formal distinction between the syntax allowed in a browser's is no formal distinction between the syntax allowed in a browser's
input dialogue box and the syntax allowed in URIs. For this reason, input dialogue box and the syntax allowed in URIs. For this reason,
no normative statements are made in this section. no normative statements are made in this section.
In practice, although parsers respect the established syntax, they In practice, although parsers respect the established syntax, they
are coded pragmatically rather than being formally syntax-driven. are coded pragmatically rather than being formally syntax-driven.
Typically, IP address literals are handled by an explicit code path. Typically, IP address literals are handled by an explicit code path.
Parsers have been inconsistent in providing for ZoneIDs. Most have Parsers have been inconsistent in providing for zone identifiers.
no support, but there have been examples of ad hoc support. For Most have no support, but there have been examples of ad hoc support.
example, some versions of Firefox allowed the use of a ZoneID For example, some versions of Firefox allowed the use of a zone
preceded by a bare "%" character, but this feature was removed for identifier preceded by a bare "%" character, but this feature was
consistency with established syntax [RFC3986]. As another example, removed for consistency with established syntax [RFC3986]. As
some versions of Internet Explorer allowed use of a ZoneID preceded another example, some versions of Internet Explorer allowed use of a
by a "%" character encoded as "%25", still beyond the syntax allowed zone identifier preceded by a "%" character encoded as "%25", still
by the established rules [RFC3986]. This syntax extension is in fact beyond the syntax allowed by the established rules [RFC3986]. This
used internally in the Windows operating system and some of its APIs. syntax extension is in fact used internally in the Windows operating
system and some of its APIs.
It is desirable for all URI parsers to recognise a ZoneID according It is desirable for all URI parsers to recognise a zone identifier
to the syntax defined in Section 3. according to the syntax defined in Section 3. Any code handling
percent-encoding or percent-decoding must be aware that the "%"
character preceding the zone identifier is never itself percent-
encoded, as specified by ABNF above. In terms of Section 2.4 of
[RFC3986], this "%" character is acting as a delimiter, not as data.
URIs including a ZoneID have no meaning outside the originating HTTP URIs including a zone identifier have no meaning outside the
client node. However, in some use cases, such as CUPS mentioned originating HTTP client node. However, in some use cases, such as
above, the URI will be reflected back to the client. CUPS mentioned above, the host address embedded in the URI will be
reflected back to the client, using exactly the representation of the
zone identifier that the client sent.
The various use cases for the ZoneID syntax will cause it to be The various use cases for the zone identifier syntax will cause it to
entered in a browser's input dialogue box. Thus, URIs including a be entered in a browser's input dialogue box. Thus, URIs including a
ZoneID are unlikely to occur in HTML documents. However, if they do zone identifier are unlikely to occur in HTML documents. However, if
(for example, in a diagnostic script coded in HTML), it would be they do (for example, in a diagnostic script coded in HTML), it would
appropriate to treat them exactly as above. be appropriate to treat them exactly as above.
5. Security Considerations 5. Security Considerations
The security considerations from the URI syntax specification The security considerations from the URI syntax specification
[RFC3986] and the IPv6 Scoped Address Architecture specification [RFC3986] and the IPv6 Scoped Address Architecture specification
[RFC4007] apply. In particular, this URI format creates a specific [RFC4007] apply. In particular, this URI format creates a specific
pathway by which a deceitful zone index might be communicated, as pathway by which a deceitful zone index might be communicated, as
mentioned in the final security consideration of the Scoped Address mentioned in the final security consideration of the Scoped Address
Architecture specification. Architecture specification.
However, this format is only meaningful for link-local addresses However, this format is only meaningful for link-local addresses
under prefix fe80::/10. It is not necessary for web browsers to under prefix fe80::/10. It is not necessary for web browsers to
verify this, or to validate the ZoneID, because the operating system verify this, or to validate the zone identifier, because the
will do so when the address is passed to the socket API, and return operating system will do so when the address is passed to the socket
an error code if the ZoneID is invalid. API, and return an error code if the zone identifier is invalid.
It is conceivable that this format could be misused to probe a local
network configuration in some way. However, that would only be
possible for an attacker that had already gained sufficient control
of a host to originate HTTP messages. Such an attacker could more
easily probe using basic mechanisms such as the "ping" command.
6. Acknowledgements 6. Acknowledgements
The lack of this format was first pointed out by Margaret Wasserman The lack of this format was first pointed out by Margaret Wasserman
and later by Kerry Lynn. A previous draft document by Bill Fenner and later by Kerry Lynn. A previous draft document by Bill Fenner
and Martin Dürst [LITERAL-ZONE] discussed this topic but was not and Martin Dürst [LITERAL-ZONE] discussed this topic but was not
finalised. Michael Sweet and Andrew Cady explained some of the finalised. Michael Sweet and Andrew Cady explained some of the
difficulties caused by RFC 6874. The ABNF syntax proposed above was difficulties caused by RFC 6874. The ABNF syntax proposed above was
drafted by Andrew Cady. drafted by Andrew Cady.
Valuable comments and contributions were made by Karl Auer, Carsten Valuable comments and contributions were made by Karl Auer, Carsten
Bormann, Benoit Claise, Martin Dürst, Stephen Farrell, Brian Bormann, Benoit Claise, Martin Dürst, Stephen Farrell, Brian
Haberman, Ted Hardie, Philip Homburg, Tatuya Jinmei, Yves Lafon, Haberman, Ted Hardie, Philip Homburg, Tatuya Jinmei, Yves Lafon,
Barry Leiba, Radia Perlman, Tom Petch, Michael Richardson, Tomoyuki Barry Leiba, Ben Maddison, Radia Perlman, Tom Petch, Michael
Sahara, Juergen Schoenwaelder, Nico Schottelius, Dave Thaler, Martin Richardson, Tomoyuki Sahara, Juergen Schoenwaelder, Nico Schottelius,
Thomson, Ole Troan, and others. Dave Thaler, Martin Thomson, Ole Troan, Shang Ye, and others.
7. References 7. References
7.1. Normative References 7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
skipping to change at page 8, line 26 skipping to change at page 9, line 21
Address Text Representation", RFC 5952, Address Text Representation", RFC 5952,
DOI 10.17487/RFC5952, August 2010, DOI 10.17487/RFC5952, August 2010,
<https://www.rfc-editor.org/info/rfc5952>. <https://www.rfc-editor.org/info/rfc5952>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>. May 2017, <https://www.rfc-editor.org/info/rfc8174>.
7.2. Informative References 7.2. Informative References
[CUPS] Apple, "CUPS open source printing system", 2021, [CUPS] Apple, "Apple CUPS", 2022, <https://www.cups.org/>.
<https://www.cups.org/>.
[LITERAL-ZONE] [LITERAL-ZONE]
Fenner, B. and M. Dürst, "Formats for IPv6 Scope Zone Fenner, B. and M. Dürst, "Formats for IPv6 Scope Zone
Identifiers in Literal Address Formats", Work in Progress, Identifiers in Literal Address Formats", Work in Progress,
October 2005. October 2005.
[OP-CUPS] Sweet, M., "OpenPrinting CUPS", 2022,
<https://openprinting.github.io/cups/>.
[RFC3493] Gilligan, R., Thomson, S., Bound, J., McCann, J., and W. [RFC3493] Gilligan, R., Thomson, S., Bound, J., McCann, J., and W.
Stevens, "Basic Socket Interface Extensions for IPv6", Stevens, "Basic Socket Interface Extensions for IPv6",
RFC 3493, DOI 10.17487/RFC3493, February 2003, RFC 3493, DOI 10.17487/RFC3493, February 2003,
<https://www.rfc-editor.org/info/rfc3493>. <https://www.rfc-editor.org/info/rfc3493>.
[RFC3510] Herriot, R. and I. McDonald, "Internet Printing
Protocol/1.1: IPP URL Scheme", RFC 3510,
DOI 10.17487/RFC3510, April 2003,
<https://www.rfc-editor.org/info/rfc3510>.
[RFC4001] Daniele, M., Haberman, B., Routhier, S., and J. [RFC4001] Daniele, M., Haberman, B., Routhier, S., and J.
Schoenwaelder, "Textual Conventions for Internet Network Schoenwaelder, "Textual Conventions for Internet Network
Addresses", RFC 4001, DOI 10.17487/RFC4001, February 2005, Addresses", RFC 4001, DOI 10.17487/RFC4001, February 2005,
<https://www.rfc-editor.org/info/rfc4001>. <https://www.rfc-editor.org/info/rfc4001>.
[RFC6874] Carpenter, B., Cheshire, S., and R. Hinden, "Representing [RFC6874] Carpenter, B., Cheshire, S., and R. Hinden, "Representing
IPv6 Zone Identifiers in Address Literals and Uniform IPv6 Zone Identifiers in Address Literals and Uniform
Resource Identifiers", RFC 6874, DOI 10.17487/RFC6874, Resource Identifiers", RFC 6874, DOI 10.17487/RFC6874,
February 2013, <https://www.rfc-editor.org/info/rfc6874>. February 2013, <https://www.rfc-editor.org/info/rfc6874>.
[RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer [RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Message Syntax and Routing", Protocol (HTTP/1.1): Message Syntax and Routing",
RFC 7230, DOI 10.17487/RFC7230, June 2014, RFC 7230, DOI 10.17487/RFC7230, June 2014,
<https://www.rfc-editor.org/info/rfc7230>. <https://www.rfc-editor.org/info/rfc7230>.
[RFC7472] McDonald, I. and M. Sweet, "Internet Printing Protocol
(IPP) over HTTPS Transport Binding and the 'ipps' URI
Scheme", RFC 7472, DOI 10.17487/RFC7472, March 2015,
<https://www.rfc-editor.org/info/rfc7472>.
Appendix A. Options Considered Appendix A. Options Considered
The syntax defined above allows a ZoneID to be added to any IPv6 The syntax defined above allows a zone identifier to be added to any
address. The 6man WG discussed and rejected an alternative in which IPv6 address. The 6man WG discussed and rejected an alternative in
the existing syntax of IPv6address would be extended by an option to which the existing syntax of IPv6address would be extended by an
add the ZoneID only for the case of link-local addresses. It was option to add the zone identifier only for the case of link-local
felt that the solution presented in this document offers more addresses. It was felt that the solution presented in this document
flexibility for future uses and is more straightforward to implement. offers more flexibility for future uses and is more straightforward
to implement.
The various syntax options considered are now briefly described. The various syntax options considered are now briefly described.
1. Leave the problem unsolved. 1. Leave the problem unsolved.
This would mean that per-interface diagnostics would still have This would mean that per-interface diagnostics would still have
to be performed using ping or ping6: to be performed using ping or ping6:
ping fe80::abcd%en1 ping fe80::abcd%en1
skipping to change at page 10, line 31 skipping to change at page 11, line 41
Advantage: allows use of browser; consistent with general URI Advantage: allows use of browser; consistent with general URI
syntax. syntax.
Disadvantage: somewhat ugly and confusing; doesn't allow simple Disadvantage: somewhat ugly and confusing; doesn't allow simple
cut and paste. cut and paste.
Appendix B. Change log Appendix B. Change log
This section is to be removed before publishing as an RFC. This section is to be removed before publishing as an RFC.
* draft-ietf-6man-rfc6874bis-01, 2022-04-07:
- Extended use cases
- Clarified relationship with RFC3986 language
- Allow for legacy use of RFC6874 format
- Augmented security considerations
- Editorial and reference improvements
* draft-ietf-6man-rfc6874bis-00, 2022-03-19: * draft-ietf-6man-rfc6874bis-00, 2022-03-19:
- WG adoption - WG adoption
- Clarified security considerations - Clarified security considerations
* draft-carpenter-6man-rfc6874bis-03, 2022-02-08: * draft-carpenter-6man-rfc6874bis-03, 2022-02-08:
- Changed to bare % signs. - Changed to bare % signs.
 End of changes. 29 change blocks. 
82 lines changed or deleted 135 lines changed or added

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