Balance Mapping for the Extensible Provisioning Protocol (EPP)
draft-gould-regext-balance-00

Network Working Group                                           J. Gould
Internet-Draft                                            VeriSign, Inc.
Intended status: Standards Track                            28 July 2025
Expires: 29 January 2026

     Balance Mapping for the Extensible Provisioning Protocol (EPP)
                     draft-gould-regext-balance-00

Abstract

   This document describes an Extensible Provisioning Protocol (EPP)
   mapping for retrieving the client balance and other financial
   information.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 29 January 2026.

Copyright Notice

   Copyright (c) 2025 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Gould                    Expires 29 January 2026                [Page 1]
Internet-Draft                   balance                       July 2025

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Conventions Used in This Document . . . . . . . . . . . .   2
   2.  Object Attributes . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  Decimal Attribute Values  . . . . . . . . . . . . . . . .   3
     2.2.  Dates and Times . . . . . . . . . . . . . . . . . . . . .   3
     2.3.  Low Balance Poll Message  . . . . . . . . . . . . . . . .   3
   3.  EPP Command Mapping . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  EPP Query Commands  . . . . . . . . . . . . . . . . . . .   4
       3.1.1.  EPP <check> Command . . . . . . . . . . . . . . . . .   4
       3.1.2.  EPP <info> Command  . . . . . . . . . . . . . . . . .   5
       3.1.3.  EPP <transfer> Command  . . . . . . . . . . . . . . .   6
     3.2.  EPP Transform Commands  . . . . . . . . . . . . . . . . .   6
       3.2.1.  EPP <create> Command  . . . . . . . . . . . . . . . .   6
       3.2.2.  EPP <delete> Command  . . . . . . . . . . . . . . . .   7
       3.2.3.  EPP <renew> Command . . . . . . . . . . . . . . . . .   7
       3.2.4.  EPP <transfer> Command  . . . . . . . . . . . . . . .   7
       3.2.5.  EPP <update> Command  . . . . . . . . . . . . . . . .   7
   4.  Formal Syntax . . . . . . . . . . . . . . . . . . . . . . . .   7
     4.1.  Balance Mapping Schema  . . . . . . . . . . . . . . . . .   7
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   8
     5.1.  XML Namespace . . . . . . . . . . . . . . . . . . . . . .   8
     5.2.  EPP Extension Registry  . . . . . . . . . . . . . . . . .   9
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
   7.  Normative References  . . . . . . . . . . . . . . . . . . . .   9
   8.  Informative References  . . . . . . . . . . . . . . . . . . .  10
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  10

1.  Introduction

   This document describes an extension mapping for version 1.0 of the
   Extensible Provisioning Protocol (EPP) [RFC5730].  This EPP mapping
   enables a client to get their financial information including the
   balance, credit limit, available credit, and credit threshold.

1.1.  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 [RFC2119] [RFC8174] 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.

Gould                    Expires 29 January 2026                [Page 2]
Internet-Draft                   balance                       July 2025

   In examples, "C:" represents lines sent by a protocol client and "S:"
   represents lines returned by a protocol server.  In examples,
   indentation and whitespace are provided only to illustrate element
   relationships and are not a required feature of this protocol.

   "balance-0.1" is used as an abbreviation for
   "urn:ietf:params:xml:ns:epp:balance-0.1".  The XML namespace prefix
   "balance" is used, but implementations MUST NOT depend on it.
   Instead, they are to employ a proper namespace-aware XML parser and
   serializer to interpret and output the XML documents.

2.  Object Attributes

2.1.  Decimal Attribute Values

   All of the EPP Balance currency object attributes use the XML decimal
   (http://www.w3.org/TR/2004/REC-xmlschema-2-20041028/#decimal) data
   type to represent the currency value in the currency of the server.
   The precision is restricted to 2 fractional digits.

2.2.  Dates and Times

   Date and time attribute values MUST be represented in Universal
   Coordinated Time (UTC) using the Gregorian calendar.  The extended
   date-time form using upper case "T" and "Z" characters defined in XML
   Schema Part 2 (http://www.w3.org/TR/2004/REC-xmlschema-2-20041028/)
   MUST be used to represent date-time values, as XML Schema does not
   support truncated date-time forms or lower case "T" and "Z"
   characters.

2.3.  Low Balance Poll Message

   The EPP <poll> command and response is defined in section 2.9.2.3 of
   [RFC5730].  For servers that support a credit threshold, the Balance
   Info Response, as defined in Section 3.1.2, is inserted into the poll
   queue whenever the available credit for an account reaches or goes
   below the credit threshold.

   Example <poll> command:

    C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
    C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
    C:  <command>
    C:  <poll op="req"/>
    C:    <clTRID>ABC-12345</clTRID>
    C:  </command>
    C:</epp>

Gould                    Expires 29 January 2026                [Page 3]
Internet-Draft                   balance                       July 2025

   Example low balance <poll> response:

   <?xml version="1.0" encoding="UTF-8" standalone="no"?>
   <epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
     <response>
       <result code="1301">
         <msg>Command completed successfully; ack to dequeue</msg>
       </result>
       <msgQ count="1" id="12345">
         <qDate>2020-09-01T15:25:01.0078Z</qDate>
         <msg>Low Account Balance</msg>
       </msgQ>
       <resData>
         <balance:infData
           xmlns:balance="urn:ietf:params:xml:ns:epp:balance-0.1">
           <balance:currency>USD</balance:currency>
           <balance:creditLimit>1000.00</balance:creditLimit>
           <balance:balance>800.00</balance:balance>
           <balance:availableCredit>200.00</balance:availableCredit>
           <balance:creditThreshold>500.00</balance:creditThreshold>
         </balance:infData>
       </resData>
       <trID>
         <clTRID>ABC-12345</clTRID>
         <svTRID>54322-XYZ</svTRID>
       </trID>
     </response>
   </epp>

3.  EPP Command Mapping

   A detailed description of the EPP syntax and semantics can be found
   in the EPP core protocol specification [RFC5730].  The command
   mappings described here are specifically for use with the Balance
   Object Mapping.

3.1.  EPP Query Commands

   EPP [RFC5730] provides three commands to retrieve object information:
   <check> to determine if an object is known to the server, <info> to
   retrieve detailed information associated with an object, and
   <transfer> to retrieve object transfer status information.

3.1.1.  EPP <check> Command

   Available check semantics do not apply to balance objects, so there
   is no mapping defined for the EPP <check> command.

Gould                    Expires 29 January 2026                [Page 4]
Internet-Draft                   balance                       July 2025

3.1.2.  EPP <info> Command

   EPP provides the <info> command that is used to retrieve client
   balance and other financial information for the currently logged-in
   client.  In addition to the standard EPP command elements, the <info>
   command MUST contain a <balance:info> element that identifies the
   balance namespace.  The <balance:info> element does not contain any
   child elements.

   Example <info> command:

   C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
   C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
   C:  <command>
   C:    <info>
   C:      <balance:info
   C:        xmlns:balance="http://www.verisign.com/epp/balance-0.1"/>
   C:    </info>
   C:    <clTRID>ABC-12345</clTRID>
   C:  </command>
   C:</epp>

   When an <info> command has been processed successfully, the EPP
   <resData> element MUST contain a child <balance:infData> element that
   identifies the balance namespace.  The <balance:infData> element
   contains the following child elements:

   <balance:currency>
       The <balance:currency> element is used to indicate the currency
       used by the account balance elements.  The value of this element
       MUST be a three- character currency code from [ISO4217_2015].
   <balance:creditLimit>
       The <balance:creditLimit> element contains the account credit
       limit using the <balance:currency> element currency.
   <balance:balance>
       The <balance:balance> element contains the account balance using
       the <balance:currency> element currency.
   <balance:availableCredit>
       The <balance:availableCredit> element that contains the account
       available credit using the <balance:currency> element currency.
       The available credit is calculated by subtracting the
       <balance:balance> element value from the <balance:creditLimit>
       element value.
   <balance:creditThreshold>
       The OPTIONAL <balance:creditThreshold> element that contains the
       low available credit fixed amount threshold, using the
       <balance:currency> element currency.  The
       <balance:creditThreshold> element MAY be included in a response

Gould                    Expires 29 January 2026                [Page 5]
Internet-Draft                   balance                       July 2025

       to an <info> command and SHOULD be included in a Low Balance Poll
       Message (as described in Section 2.3), since the
       <balance:creditThreshold> element is only relevant for the
       triggering of the Low Balance Poll Message.

   Example <info> response 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:    </result>
   S:    <resData>
   S:      <balance:infData
   S:        xmlns:balance="urn:ietf:params:xml:ns:epp:balance-0.1">
   S:        <balance:currency>USD</balance:currency>
   S:        <balance:creditLimit>1000.00</balance:creditLimit>
   S:        <balance:balance>200.00</balance:balance>
   S:        <balance:availableCredit>800.00</balance:availableCredit>
   S:        <balance:creditThreshold>500.00</balance:creditThreshold>
   S:      </balance:infData>
   S:    </resData>
   S:    <trID>
   S:      <clTRID>ABC-12345</clTRID>
   S:      <svTRID>54322-XYZ</svTRID>
   S:    </trID>
   S:  </response>
   S:</epp>

3.1.3.  EPP <transfer> Command

   Transfer semantics do not apply to balance objects, so there is no
   mapping defined for the EPP <transfer> command.

3.2.  EPP Transform Commands

   EPP provides five commands to transform objects: <create> to create
   an instance of an object, <delete> to delete an instance of an
   object, <renew> to extend the validity period of an object,
   <transfer> to manage object sponsorship changes, and <update> to
   change information associated with an object.

3.2.1.  EPP <create> Command

   Create semantics do not apply to balance objects, so there is no
   mapping defined for the EPP <create> command.

Gould                    Expires 29 January 2026                [Page 6]
Internet-Draft                   balance                       July 2025

3.2.2.  EPP <delete> Command

   Delete semantics do not apply to balance objects, so there is no
   mapping defined for the EPP <delete> command.

3.2.3.  EPP <renew> Command

   Renew semantics do not apply to balance objects, so there is no
   mapping defined for the EPP <renew> command.

3.2.4.  EPP <transfer> Command

   Transfer semantics do not apply to balance objects, so there is no
   mapping defined for the EPP <transfer> command.

3.2.5.  EPP <update> Command

   Update semantics do not apply to balance objects, so there is no
   mapping defined for the EPP <update> command.

4.  Formal Syntax

   The EPP Balance Mapping schema is presented here.

   The formal syntax shown here is a complete XML Schema representation
   of the object mapping suitable for automated validation of EPP XML
   instances.  The <CODE BEGINS> and <CODE ENDS> tags are not part of
   the XML Schema; they are used to note the beginning and ending of the
   XML Schema for URI registration purposes.

4.1.  Balance Mapping Schema

   <CODE BEGINS>
     <?xml version="1.0" encoding="UTF-8"?>
     <schema xmlns="http://www.w3.org/2001/XMLSchema"
       xmlns:balance="urn:ietf:params:xml:ns:epp:balance-0.1"
       targetNamespace="urn:ietf:params:xml:ns:epp:balance-0.1"
       elementFormDefault="qualified">
       <annotation>
         <documentation>Extensible Provisioning Protocol v1.0
           Account balance and other financial information mapping.
         </documentation>
       </annotation>
       <!--
         Child elements found in EPP commands.
       -->
       <!-- Empty balance:info command element -->
       <element name="info" />

Gould                    Expires 29 January 2026                [Page 7]
Internet-Draft                   balance                       July 2025

       <!--
         Child response elements.
       -->
       <element name="infData"
         type="balance:infDataType" />
       <!--Child elements of the balance:infData element -->
       <complexType name="infDataType">
         <sequence>
           <element name="currency"
             type="balance:currencyType" />
           <element name="creditLimit"
             type="balance:currencyValueType" />
           <element name="balance"
             type="balance:currencyValueType" />
           <element name="availableCredit"
             type="balance:currencyValueType" />
           <element name="creditThreshold"
             type="balance:currencyValueType"
             minOccurs="0"/>
         </sequence>
       </complexType>
       <simpleType name="currencyType">
         <restriction base="string">
           <pattern value="[A-Z]{3}" />
         </restriction>
       </simpleType>
       <simpleType name="currencyValueType">
         <restriction base="decimal">
           <fractionDigits value="2" />
         </restriction>
       </simpleType>
     </schema>
   <CODE ENDS>

5.  IANA Considerations

5.1.  XML Namespace

   This document uses URNs to describe XML namespaces and XML schemas
   conforming to a registry mechanism described in [RFC3688].  The
   following URI assignment has been made by IANA:

   Registration request for the balance namespace:

   URI:  urn:ietf:params:xml:ns:epp:balance-0.1
   Registrant Contact:  IESG
   XML:  None.  Namespace URIs do not represent an XML specification.

Gould                    Expires 29 January 2026                [Page 8]
Internet-Draft                   balance                       July 2025

   Registration request for the balance XML Schema:

   URI:  urn:ietf:params:xml:schema:epp:balance-0.1
   Registrant Contact:  IESG
   XML:  See the "Formal Syntax" section of this document.

5.2.  EPP Extension Registry

   The EPP extension described in this document has been registered by
   IANA in the "Extensions for the Extensible Provisioning Protocol
   (EPP)" registry described in [RFC7451].  The details of the
   registration are as follows:

   Name of Extension:  "Balance Mapping for the Extensible Provisioning
      Protocol (EPP)"
   Document Status:  Standards Track
   Reference:  (insert reference to RFC version of this document)
   Registrant Name and Email Address:  IESG, <iesg@ietf.org>
   TLDs:  Any
   IPR Disclosure:  None
   Status:  Active
   Notes:  None

6.  Security Considerations

   The mapping extensions described in this document do not provide any
   security services beyond those described by EPP [RFC5730] and
   protocol layers used by EPP.  The security considerations described
   in these other specifications apply to this specification as well.

   Financial information is confidential information for a client, so
   the server MUST have access control restrictions in place to limit
   access to financial information of the currently logged-in client.

7.  Normative References

   [ISO4217_2015]
              ISO, "Codes for the representation of currencies",
              ISO 4217:2015, August 2015,
              <https://www.iso.org/standard/64758.html>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

Gould                    Expires 29 January 2026                [Page 9]
Internet-Draft                   balance                       July 2025

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.

   [RFC5730]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)",
              STD 69, RFC 5730, DOI 10.17487/RFC5730, August 2009,
              <https://www.rfc-editor.org/info/rfc5730>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

8.  Informative References

   [RFC7451]  Hollenbeck, S., "Extension Registry for the Extensible
              Provisioning Protocol", RFC 7451, DOI 10.17487/RFC7451,
              February 2015, <https://www.rfc-editor.org/info/rfc7451>.

Author's Address

   James Gould
   VeriSign, Inc.
   12061 Bluemont Way
   Reston, VA 20190
   United States of America
   Email: jgould@verisign.com
   URI:   http://www.verisign.com

Gould                    Expires 29 January 2026               [Page 10]