draft-ietf-regext-epp-eai-00.txt		draft-ietf-regext-epp-eai-01.txt
	Network Working Group D. Belyavskiy		Network Working Group D. Belyavskiy
	Internet-Draft		Internet-Draft
	Intended status: Standards Track J. Gould		Intended status: Standards Track J. Gould
	Expires: 14 October 2021 VeriSign, Inc.		Expires: 26 January 2022 VeriSign, Inc.
	12 April 2021		25 July 2021
	Use of Internationalized Email Addresses in EPP protocol		Use of Internationalized Email Addresses in EPP protocol
	draft-ietf-regext-epp-eai-00		draft-ietf-regext-epp-eai-01
	Abstract		Abstract
	This document describes an EPP extension that permits usage of		This document describes an EPP extension that permits usage of
	Internationalized Email Addresses in the EPP protocol and specifies		Internationalized Email Addresses in the EPP protocol and specifies
	the terms when it can be used by EPP clients and servers. The		the terms when it can be used by EPP clients and servers. The
	Extensible Provisioning Protocol (EPP), being developed before		Extensible Provisioning Protocol (EPP), being developed before
	appearing the standards for Internationalized Email Addresses (EAI),		appearing the standards for Internationalized Email Addresses (EAI),
	does not support such email addresses.		does not support such email addresses.
	skipping to change at page 1, line 40 ¶		skipping to change at page 1, line 40 ¶
	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 14 October 2021.		This Internet-Draft will expire on 26 January 2022.
	Copyright Notice		Copyright Notice
	Copyright (c) 2021 IETF Trust and the persons identified as the		Copyright (c) 2021 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.
	skipping to change at page 2, line 25 ¶		skipping to change at page 2, line 25 ¶
	2. Migrating to Newer Versions of This Extension . . . . . . . . 3		2. Migrating to Newer Versions of This Extension . . . . . . . . 3
	3. Email Address Specification . . . . . . . . . . . . . . . . . 3		3. Email Address Specification . . . . . . . . . . . . . . . . . 3
	4. Functional Extension . . . . . . . . . . . . . . . . . . . . 4		4. Functional Extension . . . . . . . . . . . . . . . . . . . . 4
	5. Internationalized Email Addresses (EAI) Functional		5. Internationalized Email Addresses (EAI) Functional
	Extension . . . . . . . . . . . . . . . . . . . . . . . . 4		Extension . . . . . . . . . . . . . . . . . . . . . . . . 4
	5.1. Scope of Functional Extension . . . . . . . . . . . . . . 4		5.1. Scope of Functional Extension . . . . . . . . . . . . . . 4
	5.2. Signaling Client and Server Support . . . . . . . . . . . 5		5.2. Signaling Client and Server Support . . . . . . . . . . . 5
	5.3. Functional Extension Behavior . . . . . . . . . . . . . . 5		5.3. Functional Extension Behavior . . . . . . . . . . . . . . 5
	5.3.1. EAI Functional Extension Negotiated . . . . . . . . . 5		5.3.1. EAI Functional Extension Negotiated . . . . . . . . . 5
	5.3.2. EAI Functional Extension Not Negotiated . . . . . . . 6		5.3.2. EAI Functional Extension Not Negotiated . . . . . . . 6
			5.3.3. EAI Placeholder Email Address . . . . . . . . . . . . 7
	6. Security Considerations . . . . . . . . . . . . . . . . . . . 7		6. Security Considerations . . . . . . . . . . . . . . . . . . . 7
	7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7		7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
	7.1. XML Namespace . . . . . . . . . . . . . . . . . . . . . . 7		7.1. XML Namespace . . . . . . . . . . . . . . . . . . . . . . 7
	7.2. EPP Extension Registry . . . . . . . . . . . . . . . . . 7		7.2. EPP Extension Registry . . . . . . . . . . . . . . . . . 8
	8. Implementation Considerations . . . . . . . . . . . . . . . . 8		8. Implementation Considerations . . . . . . . . . . . . . . . . 8
	9. References . . . . . . . . . . . . . . . . . . . . . . . . . 8		9. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
	9.1. Normative References . . . . . . . . . . . . . . . . . . 8		9.1. Normative References . . . . . . . . . . . . . . . . . . 8
	9.2. Informative References . . . . . . . . . . . . . . . . . 9		9.2. Informative References . . . . . . . . . . . . . . . . . 9
	Appendix A. Change History . . . . . . . . . . . . . . . . . . . 9		Appendix A. Change History . . . . . . . . . . . . . . . . . . . 10
	A.1. Change from 00 to 01 . . . . . . . . . . . . . . . . . . 9		A.1. Change from 00 to 01 . . . . . . . . . . . . . . . . . . 10
	A.2. Change from 01 to 02 . . . . . . . . . . . . . . . . . . 9		A.2. Change from 01 to 02 . . . . . . . . . . . . . . . . . . 10
	A.3. Change from 02 to 03 . . . . . . . . . . . . . . . . . . 10		A.3. Change from 02 to 03 . . . . . . . . . . . . . . . . . . 10
	A.4. Change from 03 to 04 . . . . . . . . . . . . . . . . . . 10		A.4. Change from 03 to 04 . . . . . . . . . . . . . . . . . . 10
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11
	1. Introduction		1. Introduction
	[RFC6530] introduced the framework for Internationalized Email		[RFC6530] introduced the framework for Internationalized Email
	Addresses. To make such addresses more widely accepted, the changes		Addresses. To make such addresses more widely accepted, the changes
	to various protocols need to be introduced.		to various protocols need to be introduced.
	This document describes an Extensible Provisioning Protocol (EPP)		This document describes an Extensible Provisioning Protocol (EPP)
	extension that permits usage of Internationalized Email Addresses in		extension that permits usage of Internationalized Email Addresses in
	the EPP protocol and specifies the terms when it can be used by EPP		the EPP protocol and specifies the terms when it can be used by EPP
	skipping to change at page 4, line 24 ¶		skipping to change at page 4, line 19 ¶
	with the same or similar definitions.		with the same or similar definitions.
	The email address format is formally defined in Section 3.4.1 of		The email address format is formally defined in Section 3.4.1 of
	[RFC5322], which only consists of printable US-ASCII characters for		[RFC5322], which only consists of printable US-ASCII characters for
	both the local-part and the domain ABNF rules. In [RFC6531], the		both the local-part and the domain ABNF rules. In [RFC6531], the
	extends the Mailbox, Local-part and Domain ABNF rules in [RFC5321] to		extends the Mailbox, Local-part and Domain ABNF rules in [RFC5321] to
	support "UTF8-non-ascii", defined in Section 3.1 of [RFC6532], for		support "UTF8-non-ascii", defined in Section 3.1 of [RFC6532], for
	the local-part and U-label, defined in Section 2.3.2.1 of [RFC5890],		the local-part and U-label, defined in Section 2.3.2.1 of [RFC5890],
	for the domain. By applying the syntax rules of [RFC5322], the EPP		for the domain. By applying the syntax rules of [RFC5322], the EPP
	extensions will change from supporting only ASCII characters to		extensions will change from supporting only ASCII characters to
	supporting Internationailzed characters in the email address local-		supporting Internationailzed characters both in the email address
	part and domain-part.		local-part and domain-part.
	4. Functional Extension		4. Functional Extension
	[RFC5730] defines three types of extensions at the protocol, object,		[RFC5730] defines three types of extensions at the protocol, object,
	and command-response level, which impact the structure of the EPP		and command-response level, which impact the structure of the EPP
	messages. A Functional Extension applies a functional capability to		messages. A Functional Extension applies a functional capability to
	an existing set of EPP extensions and properties. The scope of the		an existing set of EPP extensions and properties. The scope of the
	applicable EPP extensions and applicable extension properties are		applicable EPP extensions and applicable extension properties are
	defined in the Functional Extension along with the requirements for		defined in the Functional Extension along with the requirements for
	the servers and clients that support it. The Functional Extension		the servers and clients that support it. The Functional Extension
	needs to cover the expected behavior of the supporting client or		needs to cover the expected behavior of the supporting client or
	server when interfacing with an unsupporting client or server.		server when interacting with an unsupporting client or server.
	Negotiating support for a Functional Extension is handled using the		Negotiating support for a Functional Extension is handled using the
	EPP Greeting and EPP Login services.		EPP Greeting and EPP Login services.
	5. Internationalized Email Addresses (EAI) Functional Extension		5. Internationalized Email Addresses (EAI) Functional Extension
	5.1. Scope of Functional Extension		5.1. Scope of Functional Extension
	The functional extension applies to all object extensions and		The functional extension applies to all object extensions and
	command-response extensions negotiated in the EPP session that		command-response extensions negotiated in the EPP session that
	include email address properties. Examples include the		include email address properties. Examples include the
	skipping to change at page 5, line 12 ¶		skipping to change at page 5, line 9 ¶
	registry zones (e.g., top-level domains) authorized for the client in		registry zones (e.g., top-level domains) authorized for the client in
	the EPP session apply. There is no concept of a per-client, per-		the EPP session apply. There is no concept of a per-client, per-
	zone, per-extension, or per-field setting that is used to indicate		zone, per-extension, or per-field setting that is used to indicate
	support for EAI, but instead it's a global setting that applies to		support for EAI, but instead it's a global setting that applies to
	the EPP session.		the EPP session.
	5.2. Signaling Client and Server Support		5.2. Signaling Client and Server Support
	The client and the server can signal support for the functional		The client and the server can signal support for the functional
	extension using a namespace URI in the login and greeting extension		extension using a namespace URI in the login and greeting extension
	services. The namespace URI "urn:ietf:params:xml:ns:epp:eai-0.2" is		services respectively. The namespace URI
	used to signal support for the functional extension. The client		"urn:ietf:params:xml:ns:epp:eai-0.2" is used to signal support for
	includes the namespace URI in an <svcExtension> <extURI> element of		the functional extension. The client includes the namespace URI in
	the [RFC5730] <login> Command. The server includes the namespace URI		an <svcExtension> <extURI> element of the [RFC5730] <login> Command.
	in an <svcExtension> <extURI> element of the [RFC5730] Greeting.		The server includes the namespace URI in an <svcExtension> <extURI>
			element of the [RFC5730] Greeting.
	5.3. Functional Extension Behavior		5.3. Functional Extension Behavior
	5.3.1. EAI Functional Extension Negotiated		5.3.1. EAI Functional Extension Negotiated
	If both client and server have indicated the support of the EAI		If both client and server have indicated the support of the EAI
	addresses during the session establishment, it implies possibility to		addresses during the session establishment, it implies possibility to
	process the EAI address in any message having an email property		process the EAI address in any message having an email property
	during the established EPP session. Below are the server and client		during the established EPP session. Below are the server and client
	obligations when the EAI extension has been successfuly negotiated in		obligations when the EAI extension has been successfuly negotiated in
	skipping to change at page 5, line 49 ¶		skipping to change at page 5, line 47 ¶
	* Email address validation based on EAI validation rules defined in		* Email address validation based on EAI validation rules defined in
	Section 3		Section 3
	* Storage of email properties that supports internationalized		* Storage of email properties that supports internationalized
	characters.		characters.
	* Return EAI compatible addresses for all email properties in the		* Return EAI compatible addresses for all email properties in the
	EPP responses.		EPP responses.
	The server MUST satisfy the following obligations when THE EAI		The client MUST satisfy the following obligations when THE EAI
	extension has been negotiated:		extension has been negotiated:
	* Provide EAI compatible addresses for all e-mail properties in the		* Provide EAI compatible addresses for all e-mail properties in the
	EPP session negotiated object extensions and command-response		EPP session negotiated object extensions and command-response
	extensions. For example the <contact:email> element in [RFC5733]		extensions. For example the <contact:email> element in [RFC5733]
	and the <org:email> element in [RFC8543].		and the <org:email> element in [RFC8543].
	* Provide EAI compatible addresses for all registry zones (e.g.,		* Provide EAI compatible addresses for all registry zones (e.g.,
	top-level domains) authorized for the client in the EPP session.		top-level domains) authorized for the client in the EPP session.
	* Accept EAI compatible addresses in the EPP responses for all email		* Accept EAI compatible addresses in the EPP responses for all email
	properties in the EPP session negotiated object extensions and		properties in the EPP session negotiated object extensions and
	command-response extensions.		command-response extensions.
	5.3.2. EAI Functional Extension Not Negotiated		5.3.2. EAI Functional Extension Not Negotiated
	The lack of EAI support can cause data and functional issues, so an		The lack of EAI support can cause data and functional issues, so an
	EAI supporting client or server needs to handle cases where the		EAI supporting client or server needs to handle cases where the
	opposite party doesn't support EAI. Below are the server and client		opposite party doesn't support EAI. Below are the server and client
	obligations when the EAI extension is not negotiated due to the lack		obligations when the EAI extension is not negotiated due to the lack
	of support by the opposite party.		of support by the peer.
	The EAI supporting server MUST satisfy the following obligations when		The EAI supporting server MUST satisfy the following obligations when
	the client does not support the EAI extension:		the client does not support the EAI extension:
	* When the email property is required in the EPP extension command,		* When the email property is required in the EPP extension command,
	the server SHOULD validate the email property by the client using		the server SHOULD validate the email property sent by the client
	the ASCII email validation rules.		using the ASCII email validation rules.
	* When the email property is optional according the EPP extension		* When the email property is optional according the EPP extension
	command, if the client supplies the email property the server		command, if the client supplies the email property the server
	SHOULD validate the email property using the ASCII email		SHOULD validate the email property using the ASCII email
	validation rules.		validation rules.
	* When the email property is required in the EPP extension response,		* When the email property is required in the EPP extension response,
	the server MUST validate whether the email property is an EAI		the server MUST validate whether the email property is an EAI
	address and if so return the predefined placeholder email TBD and		address and if so return the predefined placeholder email (see
	otherwise return the email property that has been set.		below) and otherwise return the email property that has been set.
	* When the email property is optional in the EPP extension response,		* When the email property is optional in the EPP extension response,
	the server MUST validate whether the email property is an EAI		the server MUST validate whether the email property is an EAI
	address and if so don't return the email property in the response		address and if so don't return the email property in the response
	and otherwise return the email property that has been set based on		and otherwise return the email property that has been set based on
	server policy.		server policy.
	The EAI supporting client MUST satisfy the following obligations when		The EAI supporting client MUST satisfy the following obligations when
	the server does not support the EAI extension:		the server does not support the EAI extension:
	* When the email property is required in the EPP extension command		* When the email property is required in the EPP extension command
	and the email property is an EAI address with no alternative ASCII		and the email property is an EAI address with no alternative ASCII
	address, the client MUST provide the predefined placeholder email		address, the client MUST provide the predefined placeholder email
	address TBD.		address (see below).
	* When the email property is optional in the EPP extension command		* When the email property is optional in the EPP extension command
	and the email property is an EAI address with no alternative ASCII		and the email property is an EAI address with no alternative ASCII
	address, the client SHOULD omit the email property.		address, the client SHOULD omit the email property.
			5.3.3. EAI Placeholder Email Address
			A valid email value needs to be provided to a non-EAI supporting
			client or server to satisfy a required email property when all that
			is available is an EAI value. To satisfy this requirement, a
			predefined placeholder email needs to be selected that meets the
			requirements:
			* A syntactically valid email address to pass client or server
			validation logic.
			* A non-EAI email address since the client or server doesn't support
			EAI email addresses.
			* A single value that can indicate the lack of EAI support to the
			client or server.
			* An email address that is blackholed and never delivered.
			* Use of the email address will not cause operational issues.
			RFC 7535 [RFC7535] defines a blackholed domain name with
			EMPTY.AS112.ARPA, which can be leveraged for the EAI predefined
			placeholder email. The proposal is to define the predefined
			placeholder email value as EAI@EMPTY.AS112.ARPA.
	6. Security Considerations		6. Security Considerations
	Registries SHOULD validate the domain names in the provided email		Registries SHOULD validate the domain names in the provided email
	addresses. This can be done by validating all code points according		addresses. This can be done by validating all code points according
	to IDNA2008 [RFC5892].		to IDNA2008 [RFC5892].
	7. IANA Considerations		7. IANA Considerations
	7.1. XML Namespace		7.1. XML Namespace
	skipping to change at page 9, line 37 ¶		skipping to change at page 10, line 5 ¶
	2119 Key Words", BCP 14, RFC 8174, DOI 10.27487/RFC8174,		2119 Key Words", BCP 14, RFC 8174, DOI 10.27487/RFC8174,
	May 2017, <https://www.rfc-editor.org/info/rfc8174>.		May 2017, <https://www.rfc-editor.org/info/rfc8174>.
	9.2. Informative References		9.2. Informative References
	[RFC5892] Faltstrom, P., Ed., "The Unicode Code Points and		[RFC5892] Faltstrom, P., Ed., "The Unicode Code Points and
	Internationalized Domain Names for Applications (IDNA)",		Internationalized Domain Names for Applications (IDNA)",
	RFC 5892, DOI 10.27487/RFC5892, August 2010,		RFC 5892, DOI 10.27487/RFC5892, August 2010,
	<https://www.rfc-editor.org/info/rfc5892>.		<https://www.rfc-editor.org/info/rfc5892>.
			[RFC7535] Abley, J., Dickson, B., Kumari, W., and G. Michaelson,
			"AS112 Redirection Using DNAME", RFC 7535,
			DOI 10.17487/RFC7535, May 2015,
			<https://www.rfc-editor.org/info/rfc7535>.
	[RFC8543] Zhou, L., Kong, N., Yao, J., Gould, J., and G. Zhou,		[RFC8543] Zhou, L., Kong, N., Yao, J., Gould, J., and G. Zhou,
	"Extensible Provisioning Protocol (EPP) Organization		"Extensible Provisioning Protocol (EPP) Organization
	Mapping", RFC 8543, DOI 10.27487/RFC8543, March 2019,		Mapping", RFC 8543, DOI 10.27487/RFC8543, March 2019,
	<https://www.rfc-editor.org/info/rfc8543>.		<https://www.rfc-editor.org/info/rfc8543>.
	Appendix A. Change History		Appendix A. Change History
	A.1. Change from 00 to 01		A.1. Change from 00 to 01
	1. Changed from update of RFC 5733 to use the "Placeholder Text and		1. Changed from update of RFC 5733 to use the "Placeholder Text and
End of changes. 17 change blocks.
	24 lines changed or deleted		57 lines changed or added
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