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login greeting URI namespace response general poll object-level command-response signal signaling The Extensible Provisioning Protocol (EPP), as defined in RFC 5730, includes a method for the client and server to determine the objects to be managed during a session and the object extensions to be used during a session. The services are identified using namespace URIs, and an "unhandled namespace" is one that is associated with a service not supported by the client. This document defines an operational practice that enables the server to return information associated with unhandled namespace URIs and that maintains compliance with the negotiated services defined in RFC 5730.

Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in 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 .

Copyright Notice Copyright (c) 2021 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 () 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.

Table of Contents

• .  Introduction
  • .  Conventions Used in This Document
• .  Unhandled Namespaces
• .  Use of EPP <extValue> for Unhandled Namespace Data
  • .  Unhandled Object-Level Extension
  • .  Unhandled Command-Response Extension
• .  Signaling Client and Server Support
• .  Usage with General EPP Responses
• .  Usage with Poll-Message EPP Responses
• .  Implementation Considerations
  • .  Client Implementation Considerations
  • .  Server Implementation Considerations
• .  IANA Considerations
  • .  XML Namespace
  • .  EPP Extension Registry
• .  Security Considerations
• . References
  • .  Normative References
  • .  Informative References
• Acknowledgements
• Authors' Addresses

Introduction The Extensible Provisioning Protocol (EPP), as defined in , includes a method for the client and server to determine the objects to be managed during a session and the object extensions to be used during a session. The services are identified using namespace URIs. How should the server handle service data that needs to be returned in the response when the client does not support the required service namespace URI, which is referred to as an "unhandled namespace"? An unhandled namespace is a significant issue for the processing of the poll messages described in , since poll messages are inserted by the server prior to knowing the supported client services, and the client needs to be capable of processing all poll messages. Returning an unhandled namespace poll message is not compliant with the negotiated services defined in , and returning an error makes the unhandled namespace poll message a poison message by halting the processing of the poll queue. An unhandled namespace is also an issue for general EPP responses when the server has information that it cannot return to the client due to the client's supported services. The server should be able to return unhandled namespace information that the client can process later. This document defines an operational practice that enables the server to return information associated with unhandled namespace URIs and that maintains compliance with the negotiated services defined in .

Conventions Used in This Document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 when, and only when, they appear in all capitals, as shown here. XML is case sensitive. Unless stated otherwise, XML specifications and examples provided in this document MUST be interpreted in the character case presented in order to develop a conforming implementation. In examples, "S:" represents lines returned by a protocol server. Indentation and white space in examples are provided only to illustrate element relationships and are not required features of this protocol. The examples reference XML namespace prefixes that are used for the associated XML namespaces. Implementations MUST NOT depend on the example XML namespaces and instead employ a proper namespace-aware XML parser and serializer to interpret and output the XML documents. The example namespace prefixes used and their associated XML namespaces include:

changePoll:

urn:ietf:params:xml:ns:changePoll-1.0

domain:

urn:ietf:params:xml:ns:domain-1.0

secDNS:

urn:ietf:params:xml:ns:secDNS-1.1

In the template example XML, placeholder content is represented by the following variables:

[NAMESPACE-XML]:

XML content associated with a login service namespace URI. An example is the <domain:infData> element content in .

[NAMESPACE-URI]:

XML namespace URI associated with the [NAMESPACE-XML] XML content. An example is "urn:ietf:params:xml:ns:domain-1.0" in .

Unhandled Namespaces An unhandled namespace is an XML namespace that is associated with a response extension that is not included in the client-specified EPP login services of . The EPP login services consist of the set of XML namespace URIs included in the <objURI> or <extURI> elements of the EPP <login> command . The services supported by the server are included in the <objURI> and <extURI> elements of the EPP <greeting> , which should be a superset of the login services included in the EPP <login> command. A server may have information associated with a specific namespace that it needs to return in the response to a client. The unhandled namespaces problem exists when the server has information that it needs to return to the client, but the namespace of the information is not supported by the client based on the negotiated EPP <login> command services.

Use of EPP <extValue> for Unhandled Namespace Data In , the <extValue> element is used to provide additional error diagnostic information, including the <value> element that identifies the client-provided element that caused a server error condition and the <reason> element containing the human-readable message that describes the reason for the error. This operational practice extends the use of the <extValue> element for the purpose of returning unhandled namespace information in a successful response. When a server has data to return to the client that the client does not support based on the login services, the server MAY return a successful response with the data for each unsupported namespace moved into an <extValue> element . The unhandled namespace will not cause an error response, but the unhandled namespace data will instead be moved to an <extValue> element, along with a reason why the unhandled namespace data could not be included in the appropriate location of the response. The <extValue> element will not be processed by the XML processor. The <extValue> element contains the following child elements:

<value>:

Contains a child element with the unhandled namespace XML. The unhandled namespace MUST be declared in the child element or any containing element, including the root element. XML processing of the <value> element is disabled by the XML schema in , so the information can safely be returned in the <value> element.

<reason>:

A formatted, human-readable message that indicates the reason the unhandled namespace data was not returned in the appropriate location of the response. The formatted reason SHOULD follow the Augmented Backus-Naur Form (ABNF) grammar format: NAMESPACE-URI " not in login services", where NAMESPACE-URI is the unhandled XML namespace like "urn:ietf:params:xml:ns:domain-1.0" in .

This document applies to the handling of unsupported namespaces for object-level extensions and command-response extensions . This document does not apply to the handling of unsupported namespaces for protocol-level extensions or authentication-information extensions . Refer to the following sections on how to handle an unsupported object-level extension namespace or an unsupported command-response extension namespace.

Unhandled Object-Level Extension An object-level extension in is a child element of the <resData> element. If the client does not handle the namespace of the object-level extension, then the <resData> element is removed and its object-level extension child element is moved into an <extValue> <value> element , with the namespace URI included in the corresponding <extValue> <reason> element. The response becomes a general EPP response without the <resData> element. Below is a template response for a supported object-level extension. The [NAMESPACE-XML] variable represents the object-level extension XML. S:<?xml version="1.0" encoding="UTF-8" standalone="no"?> S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"> S: <response> S: <result code="1000"> S: <msg>Command completed successfully</msg> S: </result> S: <resData> S: [NAMESPACE-XML] S: </resData> S: <trID> S: <clTRID>ABC-12345</clTRID> S: <svTRID>54322-XYZ</svTRID> S: </trID> S: </response> S:</epp> Below is a template for an unhandled namespace response for an unsupported object-level extension. The [NAMESPACE-XML] variable represents the object-level extension XML, and the [NAMESPACE-URI] variable represents the object-level extension XML namespace URI. S:<?xml version="1.0" encoding="UTF-8" standalone="no"?> S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"> S: <response> S: <result code="1000"> S: <msg>Command completed successfully</msg> S: <extValue> S: <value> S: [NAMESPACE-XML] S: </value> S: <reason> S: [NAMESPACE-URI] not in login services S: </reason> S: </extValue> S: </result> S: <trID> S: <clTRID>ABC-12345</clTRID> S: <svTRID>54322-XYZ</svTRID> S: </trID> S: </response> S:</epp> The EPP response is converted from an object response to a general EPP response by the server when the client does not support the object-level extension namespace URI. Below is an example of a <transfer> query response (see ) converted into an unhandled namespace response. S:<?xml version="1.0" encoding="UTF-8" standalone="no"?> S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"> S: <response> S: <result code="1000"> S: <msg>Command completed successfully</msg> S: <extValue> S: <value> S: <domain:trnData S: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0"> S: <domain:name>example.com</domain:name> S: <domain:trStatus>pending</domain:trStatus> S: <domain:reID>ClientX</domain:reID> S: <domain:reDate>2000-06-06T22:00:00.0Z</domain:reDate> S: <domain:acID>ClientY</domain:acID> S: <domain:acDate>2000-06-11T22:00:00.0Z</domain:acDate> S: <domain:exDate>2002-09-08T22:00:00.0Z</domain:exDate> S: </domain:trnData> S: </value> S: <reason> S: urn:ietf:params:xml:ns:domain-1.0 not in login services S: </reason> S: </extValue> S: </result> S: <trID> S: <clTRID>ABC-12345</clTRID> S: <svTRID>54322-XYZ</svTRID> S: </trID> S: </response> S:</epp>

Unhandled Command-Response Extension A command-response extension in is a child element of the <extension> element. If the client does not handle the namespace of the command-response extension, the command-response child element is moved into an <extValue> <value> element , with the namespace URI included in the corresponding <extValue> <reason> element. Afterwards, if there are no additional command-response child elements, the <extension> element MUST be removed. Below is a template response for a supported command-response extension. The [NAMESPACE-XML] variable represents the command-response extension XML. S:<?xml version="1.0" encoding="UTF-8" standalone="no"?> S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"> S: <response> S: <result code="1000"> S: <msg>Command completed successfully</msg> S: </result> S: <extension> S: [NAMESPACE-XML] S: </extension> S: <trID> S: <clTRID>ABC-12345</clTRID> S: <svTRID>54322-XYZ</svTRID> S: </trID> S: </response> S:</epp> Below is a template of an unhandled namespace response for an unsupported command-response extension. The [NAMESPACE-XML] variable represents the command-response extension XML, and the [NAMESPACE-URI] variable represents the command-response extension XML namespace URI. S:<?xml version="1.0" encoding="UTF-8" standalone="no"?> S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"> S: <response> S: <result code="1000"> S: <msg>Command completed successfully</msg> S: <extValue> S: <value> S: [NAMESPACE-XML] S: </value> S: <reason> S: [NAMESPACE-URI] not in login services S: </reason> S: </extValue> S: </result> S: <trID> S: <clTRID>ABC-12345</clTRID> S: <svTRID>54322-XYZ</svTRID> S: </trID> S: </response> S:</epp> The EPP response is converted to an unhandled namespace response by moving the unhandled command-response extension from under the <extension> to an <extValue> element. Below is example of the Delegation Signer (DS) Data Interface <info> response (see ) converted to an unhandled namespace response. S:<?xml version="1.0" encoding="UTF-8" standalone="no"?> S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0" S: xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> S: <response> S: <result code="1000"> S: <msg>Command completed successfully</msg> S: <extValue> S: <value> S: <secDNS:infData S: xmlns:secDNS="urn:ietf:params:xml:ns:secDNS-1.1"> S: <secDNS:dsData> S: <secDNS:keyTag>12345</secDNS:keyTag> S: <secDNS:alg>3</secDNS:alg> S: <secDNS:digestType>1</secDNS:digestType> S: <secDNS:digest>49FD46E6C4B45C55D4AC</secDNS:digest> S: </secDNS:dsData> S: </secDNS:infData> S: </value> S: <reason> S: urn:ietf:params:xml:ns:secDNS-1.1 not in login services S: </reason> S: </extValue> S: </result> S: <resData> S: <domain:infData S: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0"> S: <domain:name>example.com</domain:name> S: <domain:roid>EXAMPLE1-REP</domain:roid> S: <domain:status s="ok"/> S: <domain:registrant>jd1234</domain:registrant> S: <domain:contact type="admin">sh8013</domain:contact> S: <domain:contact type="tech">sh8013</domain:contact> S: <domain:ns> S: <domain:hostObj>ns1.example.com</domain:hostObj> S: <domain:hostObj>ns2.example.com</domain:hostObj> S: </domain:ns> S: <domain:host>ns1.example.com</domain:host> S: <domain:host>ns2.example.com</domain:host> S: <domain:clID>ClientX</domain:clID> S: <domain:crID>ClientY</domain:crID> S: <domain:crDate>1999-04-03T22:00:00.0Z</domain:crDate> S: <domain:upID>ClientX</domain:upID> S: <domain:upDate>1999-12-03T09:00:00.0Z</domain:upDate> S: <domain:exDate>2005-04-03T22:00:00.0Z</domain:exDate> S: <domain:trDate>2000-04-08T09:00:00.0Z</domain:trDate> S: <domain:authInfo> S: <domain:pw>2fooBAR</domain:pw> S: </domain:authInfo> S: </domain:infData> S: </resData> S: <trID> S: <clTRID>ABC-12345</clTRID> S: <svTRID>54322-XYZ</svTRID> S: </trID> S: </response> S:</epp>

Signaling Client and Server Support This document does not define new EPP protocol elements but rather specifies an operational practice using the existing EPP protocol, where the client and the server can signal support for the operational practice using a namespace URI in the login and greeting extension services. The namespace URI "urn:ietf:params:xml:ns:epp:unhandled-namespaces-1.0" is used to signal support for the operational practice. The client includes the namespace URI in an <svcExtension> <extURI> element of the <login> command . The server includes the namespace URI in an <svcExtension> <extURI> element of the greeting . A client that receives the namespace URI in the server's greeting extension services can expect the following supported behavior by the server:

• support unhandled namespace object-level extensions and command-response extensions in EPP poll messages, per
• support the option of unhandled namespace command-response extensions in general EPP responses, per

A server that receives the namespace URI in the client's <login> command extension services can expect the following supported behavior by the client:

• support monitoring the EPP poll messages and general EPP responses for unhandled namespaces

Usage with General EPP Responses The unhandled namespace approach defined in MAY be used for a general EPP response to an EPP command. A general EPP response includes any EPP response that is not a poll message. The use of the unhandled namespace approach for poll-message EPP responses is defined in . The server MAY exclude the unhandled namespace information in the general EPP response or MAY include it using the unhandled namespace approach. The unhandled namespace approach for general EPP responses SHOULD only be applicable to command-response extensions, defined in , since the server SHOULD NOT accept an object-level EPP command if the client did not include the object-level namespace URI in the login services. An object-level EPP response extension is returned when the server successfully executes an object-level EPP command extension. The server MAY return an unhandled object-level extension to the client, as defined in . Returning domain name Redemption Grace Period (RGP) data, based on , provides an example of applying the unhandled namespace approach for a general EPP response. If the client does not include the "urn:ietf:params:xml:ns:rgp-1.0" namespace URI in the login services and the domain <info> response of a domain name does have RGP information, the server MAY exclude the <rgp:infData> element from the EPP response or MAY include it under the <extValue> element, per . Below is an example of a domain name <info> response converted to an unhandled <rgp:infData> element (see ) included under an <extValue> element: S:<?xml version="1.0" encoding="UTF-8" standalone="no"?> S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0" S: xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" S: xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0 S: epp-1.0.xsd"> S: <response> S: <result code="1000"> S: <msg>Command completed successfully</msg> S: <extValue> S: <value> S: <rgp:infData xmlns:rgp="urn:ietf:params:xml:ns:rgp-1.0" S: xsi:schemaLocation="urn:ietf:params:xml:ns:rgp-1.0 S: rgp-1.0.xsd"> S: <rgp:rgpStatus s="redemptionPeriod"/> S: </rgp:infData> S: </value> S: <reason> S: urn:ietf:params:xml:ns:rgp-1.0 not in login services S: </reason> S: </extValue> S: </result> S: <resData> S: <domain:infData S: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0" S: xsi:schemaLocation="urn:ietf:params:xml:ns:domain-1.0 S: domain-1.0.xsd"> S: <domain:name>example.com</domain:name> S: <domain:roid>EXAMPLE1-REP</domain:roid> S: <domain:status s="pendingDelete"/> S: <domain:registrant>jd1234</domain:registrant> S: <domain:contact type="admin">sh8013</domain:contact> S: <domain:contact type="tech">sh8013</domain:contact> S: <domain:ns> S: <domain:hostObj>ns1.example.com</domain:hostObj> S: <domain:hostObj>ns1.example.net</domain:hostObj> S: </domain:ns> S: <domain:host>ns1.example.com</domain:host> S: <domain:host>ns2.example.com</domain:host> S: <domain:clID>ClientX</domain:clID> S: <domain:crID>ClientY</domain:crID> S: <domain:crDate>1999-04-03T22:00:00.0Z</domain:crDate> S: <domain:upID>ClientX</domain:upID> S: <domain:upDate>1999-12-03T09:00:00.0Z</domain:upDate> S: <domain:exDate>2005-04-03T22:00:00.0Z</domain:exDate> S: <domain:trDate>2000-04-08T09:00:00.0Z</domain:trDate> S: <domain:authInfo> S: <domain:pw>2fooBAR</domain:pw> S: </domain:authInfo> S: </domain:infData> S: </resData> S: <trID> S: <clTRID>ABC-12345</clTRID> S: <svTRID>54322-XYZ</svTRID> S: </trID> S: </response> S:</epp>

Usage with Poll-Message EPP Responses The unhandled namespace approach, defined in , MUST be used if there is unhandled namespace information included in a <poll> response. The server inserts poll messages into the client's poll queue independent of knowing the supported client login services; therefore, there may be unhandled object-level extensions and command-response extensions included in a client's poll queue. In , the <poll> command is used by the client to retrieve and acknowledge poll messages that have been inserted by the server. The <poll> response is an EPP response that includes the <msgQ> element that provides poll queue metadata about the message. The unhandled namespace approach, defined in , is used for an unhandled object-level extension and for each of the unhandled command-response extensions attached to the <poll> response. The resulting <poll> response MAY have either or both the object-level extension or command-response extensions moved to <extValue> elements, as defined in . The change poll message, as defined in , which is an extension of any EPP object, is an example of applying the unhandled namespace approach for <poll> responses. Below are examples of converting the domain name <info> response example in to an unhandled namespace response. The object that will be used in the examples is a domain name object . Below is a domain name <info> <poll> response with the unhandled <changePoll:changeData> element included under an <extValue> element. S:<?xml version="1.0" encoding="UTF-8" standalone="no"?> S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"> S: <response> S: <result code="1301"> S: <msg lang="en-US"> S: Command completed successfully; ack to dequeue</msg> S: <extValue> S: <value> S: <changePoll:changeData S: xmlns:changePoll="urn:ietf:params:xml:ns:changePoll-1.0" S: state="after"> S: <changePoll:operation>update</changePoll:operation> S: <changePoll:date> S: 2013-10-22T14:25:57.0Z</changePoll:date> S: <changePoll:svTRID>12345-XYZ</changePoll:svTRID> S: <changePoll:who>URS Admin</changePoll:who> S: <changePoll:caseId type="urs">urs123 S: </changePoll:caseId> S: <changePoll:reason>URS Lock</changePoll:reason> S: </changePoll:changeData> S: </value> S: <reason> S: urn:ietf:params:xml:ns:changePoll-1.0 not in login services S: </reason> S: </extValue> S: </result> S: <msgQ count="201" id="1"> S: <qDate>2013-10-22T14:25:57.0Z</qDate> S: <msg>Registry initiated update of domain.</msg> S: </msgQ> S: <resData> S: <domain:infData S: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0"> S: <domain:name>domain.example</domain:name> S: <domain:roid>EXAMPLE1-REP</domain:roid> S: <domain:status s="ok"/> S: <domain:registrant>jd1234</domain:registrant> S: <domain:contact type="admin">sh8013</domain:contact> S: <domain:contact type="tech">sh8013</domain:contact> S: <domain:clID>ClientX</domain:clID> S: <domain:crID>ClientY</domain:crID> S: <domain:crDate>2012-04-03T22:00:00.0Z</domain:crDate> S: <domain:exDate>2014-04-03T22:00:00.0Z</domain:exDate> S: </domain:infData> S: </resData> S: <trID> S: <clTRID>ABC-12345</clTRID> S: <svTRID>54322-XYZ</svTRID> S: </trID> S: </response> S:</epp> Below is an unhandled domain name <info> <poll> response and the unhandled <changePoll:changeData> element included under an <extValue> element. S:<?xml version="1.0" encoding="UTF-8" standalone="no"?> S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"> S: <response> S: <result code="1301"> S: <msg>Command completed successfully; ack to dequeue</msg> S: <extValue> S: <value> S: <domain:infData S: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0"> S: <domain:name>domain.example</domain:name> S: <domain:roid>EXAMPLE1-REP</domain:roid> S: <domain:status s="ok"/> S: <domain:registrant>jd1234</domain:registrant> S: <domain:contact type="admin">sh8013</domain:contact> S: <domain:contact type="tech">sh8013</domain:contact> S: <domain:clID>ClientX</domain:clID> S: <domain:crID>ClientY</domain:crID> S: <domain:crDate>2012-04-03T22:00:00.0Z</domain:crDate> S: <domain:exDate>2014-04-03T22:00:00.0Z</domain:exDate> S: </domain:infData> S: </value> S: <reason> S: urn:ietf:params:xml:ns:domain-1.0 not in login services S: </reason> S: </extValue> S: <extValue> S: <value> S: <changePoll:changeData S: xmlns:changePoll= S: "urn:ietf:params:xml:ns:changePoll-1.0" S: state="after"> S: <changePoll:operation>update</changePoll:operation> S: <changePoll:date> S: 2013-10-22T14:25:57.0Z</changePoll:date> S: <changePoll:svTRID>12345-XYZ</changePoll:svTRID> S: <changePoll:who>URS Admin</changePoll:who> S: <changePoll:caseId type="urs">urs123 S: </changePoll:caseId> S: <changePoll:reason>URS Lock</changePoll:reason> S: </changePoll:changeData> S: </value> S: <reason> S: urn:ietf:params:xml:ns:changePoll-1.0 not in login services S: </reason> S: </extValue> S: </result> S: <msgQ count="201" id="1"> S: <qDate>2013-10-22T14:25:57.0Z</qDate> S: <msg>Registry initiated update of domain.</msg> S: </msgQ> S: <trID> S: <clTRID>ABC-12345</clTRID> S: <svTRID>54322-XYZ</svTRID> S: </trID> S: </response> S:</epp>

Implementation Considerations There are implementation considerations for the client and the server to help address the risk of the client ignoring unhandled namespace information included in an EPP response that is needed to meet technical, policy, or legal requirements.

Client Implementation Considerations To reduce the likelihood of a client receiving unhandled namespace information, the client should consider implementing the following:

1. Ensure that the client presents the complete set of what it supports when presenting its login services. If there are gaps between the services supported by the client and the login services included in the login command, the client may receive unhandled namespace information that the client could have supported.
2. Support all of the services included in the server greeting services that may be included in an EPP response, including the <poll> responses. The client should evaluate the gaps between the greeting services and the login services provided in the login command to identify extensions that need to be supported.
3. Proactively monitor for unhandled namespace information in the EPP responses by looking for the inclusion of the <extValue> element in successful responses, record the unsupported namespace included in the <reason> element, and record the unhandled namespace information included in the <value> element for later processing. The unhandled namespace should be implemented by the client to ensure that information is processed fully in future EPP responses.

Server Implementation Considerations To assist the clients in recognizing unhandled namespaces, the server should consider implementing the following:

1. Monitor for returning unhandled namespace information to clients and report it to the clients out of band to EPP, so the clients can add support for the unhandled namespaces.
2. Look for the unhandled namespace support in the login services when returning optional unhandled namespace information in general EPP responses.

IANA Considerations

XML Namespace This document uses URNs to describe XML namespaces conforming to a registry mechanism described in . The following URI assignment has been made by IANA.

URI:

urn:ietf:params:xml:ns:epp:unhandled-namespaces-1.0

Registrant Contact:

IESG

XML:

None. Namespace URIs do not represent an XML specification.

EPP Extension Registry The EPP operational practice described in this document has been registered by IANA in the "Extensions for the Extensible Provisioning Protocol (EPP)" registry described in . The details of the registration are as follows:

Name of Extension:

"Extensible Provisioning Protocol (EPP) Unhandled Namespaces"

Document Status:

Standards Track

Reference:

RFC 9038

Registrant:

IETF, <iesg@ietf.org>

TLDs:

Any

IPR Disclosure:

None

Status:

Active

Notes:

None

Security Considerations This document does not provide any security services beyond those described by EPP and protocol layers used by EPP. The security considerations described in these other specifications apply to this specification as well. Since the unhandled namespace content is XML that is not processed in the first pass by the XML parser, the client SHOULD validate the XML when the content is processed to protect against the inclusion of malicious content.

References Normative References In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. This document describes an IANA maintained registry for IETF standards which use Extensible Markup Language (XML) related items such as Namespaces, Document Type Declarations (DTDs), Schemas, and Resource Description Framework (RDF) Schemas. Internet technical specifications often need to define a formal syntax. Over the years, a modified version of Backus-Naur Form (BNF), called Augmented BNF (ABNF), has been popular among many Internet specifications. The current specification documents ABNF. It balances compactness and simplicity with reasonable representational power. The differences between standard BNF and ABNF involve naming rules, repetition, alternatives, order-independence, and value ranges. This specification also supplies additional rule definitions and encoding for a core lexical analyzer of the type common to several Internet specifications. [STANDARDS-TRACK] This document describes an application-layer client-server protocol for the provisioning and management of objects stored in a shared central repository. Specified in XML, the protocol defines generic object management operations and an extensible framework that maps protocol operations to objects. This document includes a protocol specification, an object mapping template, and an XML media type registration. This document obsoletes RFC 4930. [STANDARDS-TRACK] This document describes an Extensible Provisioning Protocol (EPP) mapping for the provisioning and management of Internet domain names stored in a shared central repository. Specified in XML, the mapping defines EPP command syntax and semantics as applied to domain names. This document obsoletes RFC 4931. [STANDARDS-TRACK] RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings. Informative References The Extensible Provisioning Protocol (EPP) is an application layer client-server protocol for the provisioning and management of objects stored in a shared central repository. Specified in XML, the protocol defines generic object management operations and an extensible framework that maps protocol operations to objects. This document presents guidelines for use of EPP's extension mechanisms to define new features and object management capabilities. This memo provides information for the Internet community. This document describes an Extensible Provisioning Protocol (EPP) extension mapping for the management of Domain Name System (DNS) domain names subject to "grace period" policies defined by the Internet Corporation for Assigned Names and Numbers (ICANN). Grace period policies exist to allow protocol actions to be reversed or otherwise revoked during a short period of time after the protocol action has been performed. Specified in XML, this mapping extends the EPP domain name mapping to provide additional features required for grace period processing. [STANDARDS-TRACK] This document describes an Extensible Provisioning Protocol (EPP) extension mapping for the provisioning and management of Domain Name System security (DNSSEC) extensions for domain names stored in a shared central repository. Specified in XML, this mapping extends the EPP domain name mapping to provide additional features required for the provisioning of DNS security extensions. This document obsoletes RFC 4310. [STANDARDS-TRACK] The Extensible Provisioning Protocol (EPP) includes features to add functionality by extending the protocol. It does not, however, describe how those extensions are managed. This document describes a procedure for the registration and management of extensions to EPP, and it specifies a format for an IANA registry to record those extensions. This document describes an Extensible Provisioning Protocol (EPP) extension for notifying clients of operations on client-sponsored objects that were not initiated by the client through EPP. These operations may include contractual or policy requirements including, but not limited to, regular batch processes, customer support actions, Uniform Domain-Name Dispute-Resolution Policy (UDRP) or Uniform Rapid Suspension (URS) actions, court-directed actions, and bulk updates based on customer requests. Since the client is not directly involved or knowledgable of these operations, the extension is used along with an EPP object mapping to provide the resulting state of the postoperation object, and optionally a preoperation object, with the operation metadata of what, when, who, and why.

Acknowledgements The authors wish to thank the following people for their feedback and suggestions: , , , and .

Authors' Addresses VeriSign, Inc.

12061 Bluemont Way Reston VA 20190 United States of America jgould@verisign.com http://www.verisign.com

SWITCH

P.O. Box Zurich 8021 Switzerland martin.casanova@switch.ch http://www.switch.ch