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Internet Engineering Task Force                               H. Wu
Internet Draft                                                Z. Li
Intended status: Experimental                                 J. Chen
Expires: June 24 2020                                         X. Fan
          China Academy of Information and Communications Technology
                                                    December 25, 2019
   Industrial Internet Identifier Node (IIIN) Data Escrow Specification
             draft-industrial-internet-identifier-data-escrow-00


Abstract

   This document specifies the format and contents of data escrow
   deposits targeted primarily for Industrial Internet Identifier Node
   (IIIN) which provides identifier registration. However, this
   specification was designed to be independent of the underlying
   objects that are being escrowed, therefore it could be used for
   purposes other than IIIN.

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), its areas, and its working groups.  Note that
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   Internet-Drafts are draft documents valid for a maximum of six
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   at any time.  It is inappropriate to use Internet-Drafts as
   reference material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt

   The list of Internet-Draft Shadow Directories can be accessed at
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   This Internet-Draft will expire on June 25, 2020.

Copyright Notice

   Copyright (c) 2019 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
   (http://trustee.ietf.org/license-info) in effect on the date of



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   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


   1. Introduction ................................................ 2
   2. Conventions used in this document............................ 3
   3. General Conventions ......................................... 4
      3.1. Date and Time .......................................... 4
      3.2. IP Addresses ........................................... 4
   4. Protocol Description......................................... 4
      4.1. Root element <deposit>.................................. 4
      4.2. Child <watermark> element............................... 7
      4.3. Child <indeMenu> element................................ 7
      4.4. Child <deletes> element................................. 8
      4.5. Child <contents> element................................ 8
   5. Formal Syntax ............................................... 9
      5.1. INDE Schema ............................................ 9
   6. Internationalization Considerations......................... 13
   7. Security Considerations..................................... 13
   8. IANA Considerations ........................................ 14
   9. Privacy Considerations...................................... 14
   10. References ................................................ 14
      10.1. Normative References.................................. 14
      10.2. Informative References................................ 15
   11. Acknowledgments ........................................... 15

1. Introduction

   Industrial Internet Identifier Node (IIIN) Data Escrow is the
   process by which an IIIN periodically submits data deposits to a
   third-party called an escrow agent. These deposits comprise the
   minimum data needed by a third-party to resume operations if the
   IIIN cannot function and is unable or unwilling to facilitate an
   orderly transfer of service. For an IIIN, the data to be deposited
   would include all the objects related to registered identifier.

   The goal of data escrow is higher resiliency of registration
   services, for the benefit of Internet users. The beneficiaries of an
   IIIN are not just those registering information there, but all
   relying parties that need to identify the owners of objects.



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   In the context of industry identifier namespace, data escrow is a
   requirement for IIIN. There is also a similar requirement for IIIN
   accredited identifier registration node.

   This document specifies a format for data escrow deposits
   independent of the objects being escrowed. A specification is
   required for each type of registry/set of objects that is expected
   to be escrowed.

2. 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.

   Deposit.  Deposits can be of two kinds: Full and Differential. For
   all kinds of deposits, the universe of registry objects to be
   considered for data escrow is those objects necessary in order to
   offer the registry services.

   Differential Deposit.  Contains data that reflects all transactions
   involving the database that were not reflected in the last previous
   Full, or Differential Deposit, as the case may be. Differential
   Deposit files will contain information from all database objects
   that were added, modified or deleted since the previous deposit was
   completed as of its defined Timeline Watermark.

   Full Deposit.  Contains the registry data that reflects the current
   and complete registry database and will consist of data that
   reflects the state of the IIIN as of a defined Timeline Watermark
   for the deposit.

   Escrow Agent.  The organization designated by the IIIN or the third-
   party beneficiary to receive and guard data escrow deposits from the
   IIIN.

   Third-Party Beneficiary.  Is the organization that, under
   extraordinary circumstances, would receive the escrow deposits the
   IIIN transferred to the escrow agent.  This organization could be a
   backup IIIN, contracting party of the IIIN, etc.

   Timeline Watermark.  Point in time on which to base the collecting
   of database objects for a deposit. Deposits are expected to be
   consistent to that point in time.



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3. General Conventions

   The XML namespace prefix "inde" is used for the namespace
   "urn:ietf:params:xml:ns:inde-1.0", but implementations MUST NOT
   depend on it; instead, they should employ a proper namespace-aware
   XML parser and serializer to interpret and output the XML documents.

   The XML namespace prefix "indeObj1" and "indeObj2" with the
   corresponding namespace "urn:ietf:params:xml:ns:indeObj1-1.0" and
   "urn:ietf:params:xml:ns:indeObj2-1.0" are used as example data
   escrow objects.

3.1. Date and Time

   Numerous fields indicate "dates", such as the creation and expiry
   dates for objects.  These fields SHALL contain timestamp indicating
   the date and time in UTC, specified in Internet Date/Time Format
   (see [RFC3339], Section 5.6) with the time-offset specified as "Z".

3.2. IP Addresses

   The syntax for IPv4 addresses described in this document MUST
   conform to [RFC5730].  The syntax for IPv6 addresses described in
   this document MUST conform to [RFC4291].  Practical considerations
   for publishing IPv6 address information in zone files are documented
   in [RFC2874] and [RFC3596].  A server MAY reject IP addresses that
   have not been allocated for public use by IANA.

 4. Protocol Description

   The following is a format for data escrow deposits as produced by an
   IIIN.  The deposits are represented in XML.  Only the format of the
   objects deposited is defined, nothing is prescribed about the method
   used to transfer such deposits between the IIIN and the escrow agent
   or vice versa.

   The protocol intends to be object agnostic allowing the "overload"
   of abstract elements using the "substitutionGroup" attribute of the
   XML Schema element to define the actual elements of an object to be
   escrowed.

4.1. Root element <deposit>

   The container or root element for an IIIN Data Escrow deposit is
   <deposit>.  This element contains the following child elements:
   <watermark>, <indeMenu>, <deletes> and <contents> elements.  This
   element also contains the following attributes:


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   o A REQUIRED "type" attribute that is used to identify the kind of
      deposit: FULL (Full), or DIFF (Differential).

   o A REQUIRED "id" attribute that is used to uniquely identify the
      escrow deposit.  Each IIIN is responsible for maintaining its own
      escrow deposits identifier space to ensure uniqueness.

   o An OPTIONAL "prevId" attribute that can be used to identify the
      previous Differential or Full Deposit. This attribute MUST be
      used in Differential Deposits ("DIFF" type).

   o An OPTIONAL "resend" attribute that is incremented each time the
      escrow deposit failed the verification procedure at the receiving
      party and a new escrow deposit needs to be generated by the IIIN
      for that specific date. The first time a deposit is generated the
      attribute is either omitted or MUST be "0".  If a deposit needs
      to be generated again, the attribute MUST be set to "1", and so
      on.

   Example of a Full Deposit with the two example objects indeObj1 and
   indeObj2:

   <?xml version="1.0" encoding="utf-8"?>

   <inde:deposit xmlns:inde="urn:ietf:params:xml:ns:inde-1.0"
   xmlns:indeObj1="urn:ietf:params:xml:ns:indeObj1-1.0"
   xmlns:indeObj2="urn:ietf:params:xml:ns:indeObj2-1.0" type="FULL"
   id="20191017001">

     <inde:watermark>2019-12-20T00:00:00Z</inde:watermark>

     <inde:indeMenu>

       <inde:version>1.0</inde:version>

       <inde:objURI>urn:ietf:params:xml:ns:indeObj1-1.0</inde:objURI>

       <inde:objURI>urn:ietf:params:xml:ns:indeObj2-1.0</inde:objURI>

     </inde:indeMenu>

     <inde:contents>

       <indeObj1:indeObj1>

         <indeObj1:name>EXAMPLE1</indeObj1:name>



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       </indeObj1:indeObj1>

       <indeObj2:indeObj2>

         <indeObj2:id>EXAMPLE2</indeObj2:id>

       </indeObj2:indeObj2>

     </inde:contents>

   </inde:deposit>

   Example of a Differential Deposit with the two example objects
   indeObj1 and indeObj2:

   <?xml version="1.0" encoding="UTF-8"?>

      <inde:deposit

        xmlns:inde="urn:ietf:params:xml:ns:inde-1.0"

        xmlns:indeObj1="urn:ietf:params:xml:ns:indeObj1-1.0"

        xmlns:indeObj2="urn:ietf:params:xml:ns:indeObj2-1.0"

        type="DIFF" id="20191221001" prevId="20191220001">

        <inde:watermark>2019-12-21T00:00:00Z</inde:watermark>

        <inde:indeMenu>

          <inde:version>1.0</inde:version>

            <inde:objURI>

               urn:ietf:params:xml:ns:indeObj1-1.0

            </inde:objURI>

            <inde:objURI>

              urn:ietf:params:xml:ns:indeObj2-1.0

           </inde:objURI>

        </inde:indeMenu>



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        <inde:deletes>

          <indeObj1:delete>

            <indeObj1:name>EXAMPLE1</indeObj1:name>

          </indeObj1:delete>

          <indeObj2:delete>

            <indeObj2:id>EXAMPLE2</indeObj2:id>

          </indeObj2:delete>

        </inde:deletes>

        <inde:contents>

          <indeObj1:indeObj1>

            <indeObj1:name>EXAMPLE3</indeObj1:name>

          </indeObj1:indeObj1>

          <indeObj2:indeObj2>

            <indeObj2:id>EXAMPLE4</indeObj2:id>

          </indeObj2:indeObj2>

        </inde:contents>

      </inde:deposit>

4.2. Child <watermark> element

   A REQUIRED <watermark> element contains the data-time corresponding
   to the Timeline Watermark of the deposit.

4.3. Child <indeMenu> element

   This element contains auxiliary information of the data escrow
   deposit. A REQUIRED <indeMenu> element contains the following child
   elements:

   o A REQUIRED <version> element that identifies the INDE protocol
      version.


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   o One or more <objURI> elements that contain namespace URIs
      representing the <contents> and <deletes> element objects.

4.4. Child <deletes> element

   This element SHOULD be present in deposits of type Differential. It
   contains the list of objects that were deleted since the base
   previous deposit. Each object in this section SHALL contain an
   identifier for the object deleted.

   This section of the deposit SHOULD NOT be present in Full Deposits.
   When rebuilding an IIIN it SHOULD be ignored if present in a Full
   Deposit.

   The specification for each object to be escrowed MUST declare the
   identifier to be used to reference the object to be deleted.


4.5. Child <contents> element

   This element of the deposit contains the objects in the deposit. It
   MUST be present in all type of deposits. It contains the data for
   the objects to be escrowed. The actual objects had to be specified
   individually.

   In the case of Differential Deposits, the objects indicate whether
   the object was added or modified after the base previous deposit. In
   order to distinguish between one and the other, it will be
   sufficient to check existence of the reference object of the
   previous deposit.

   When applying Differential Deposits (when rebuilding the IIIN from
   data escrow deposits) the relative order of the <deletes> elements
   is important, as is the relative order of the <contents> elements.
   All the <deletes> elements MUST be applied first, in the order that
   they appear.  All the <contents> elements MUST be applied next, in
   the order that they appear.

   If an object is present in the <contents> section of several
   deposits (e.g.  Full and Differential) the IIIN data from the latest
   deposit (as defined by the Timeline Watermark) SHOULD be used when
   rebuilding the IIIN.






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5. Formal Syntax

5.1. INDE Schema

   Copyright (c) 2019 IETF Trust and the persons identified as authors
   of the code. All rights reserved.

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

   o Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.

   o Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in
      the documentation and/or other materials provided with the
      distribution.

   o Neither the name of Internet Society, IETF or IETF Trust, nor the
      names of specific contributors, may be used to endorse or promote
      products derived from this software without specific prior
      written permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   POSSIBILITY OF SUCH DAMAGE.

   BEGIN

     <?xml version="1.0" encoding="UTF-8"?>

     <schema targetNamespace="urn:ietf:params:xml:ns:inde-1.0"

       xmlns:inde="urn:ietf:params:xml:ns:inde-1.0"

       xmlns="http://www.w3.org/2001/XMLSchema"



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       elementFormDefault="qualified">

       <annotation>

         <documentation>

        Industrial Internet Identifier Node (IIIN) Data Escrow Schema

         </documentation>

       </annotation>

       <!-- Root element -->

       <element name="deposit" type="inde:escrowDepositType"/>

       <!-- INDE types -->

       <complexType name="escrowDepositType">

         <sequence>

           <element name="watermark" type="dateTime"/>

           <element name="indeMenu" type="inde:indeMenuType"/>

           <element name="deletes" type="inde:deletesType"
             minOccurs="0"/>

           <element name="contents" type="inde:contentsType"/>

         </sequence>

         <attribute name="type" type="inde:depositTypeType"
             use="required"/>

         <attribute name="id" type="inde:depositIdType"
             use="required"/>

         <attribute name="prevId" type="inde:depositIdType"/>

         <attribute name="resend" type="unsignedShort" default="0"/>

       </complexType>

       <!-- Menu type -->



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       <complexType name="indeMenuType">

         <sequence>

           <element name="version" type="inde:versionType"/>

           <element name="objURI" type="anyURI" maxOccurs="unbounded"/>

         </sequence>

       </complexType>

       <!-- Deletes Type -->

       <complexType name="deletesType">

         <sequence minOccurs="0" maxOccurs="unbounded">

           <element ref="inde:delete"/>

         </sequence>

       </complexType>

       <element name="delete" type="inde:deleteType" abstract="true" />

       <complexType name="deleteType">

         <complexContent>

           <restriction base="anyType"/>

         </complexContent>

       </complexType>

       <!-- Contents Type -->

       <complexType name="contentsType">

         <sequence maxOccurs="unbounded">

           <element ref="inde:content"/>

         </sequence>

       </complexType>


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       <element name="content"

       type="inde:contentType" abstract="true" />

       <complexType name="contentType">

         <complexContent>

           <restriction base="anyType"/>

         </complexContent>

       </complexType>

       <!-- Type of deposit -->

       <simpleType name="depositTypeType">

         <restriction base="token">

           <enumeration value="FULL"/>

           <enumeration value="DIFF"/>

         </restriction>

       </simpleType>

       <!-- Deposit identifier type -->

       <simpleType name="depositIdType">

         <restriction base="token">

           <pattern value="\w{1,13}"/>

         </restriction>

       </simpleType>

        <!--INDE version number is a dotted pair of decimal numbers -->

       <simpleType name="versionType">

         <restriction base="token">

           <pattern value="[1-9]+\.[0-9]+"/>


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           <enumeration value="1.0"/>

         </restriction>

       </simpleType>

     </schema>

     END

6. Internationalization Considerations

   Data escrow deposits are represented in XML, which provides native
   support for encoding information using the Unicode character set and
   its more compact representations including UTF-8.  Conformant XML
   processors recognize both UTF-8 and UTF-16.  Though XML includes
   provisions to identify and use other character encodings through use
   of an "encoding" attribute in an <?xml?> declaration, use of UTF-8
   is RECOMMENDED.

7. Security Considerations

   This specification does not define the security mechanisms to be
   used in the transmission of the data escrow deposits, since it only
   specifies the minimum necessary to enable the rebuilding of an IIIN
   from deposits without intervention from the original IIIN.

   Depending on local policies, some elements or most likely, the whole
   deposit will be considered confidential.  As such the IIIN
   transmitting the data to the escrow agent SHOULD take all the
   necessary precautions like encrypting the data itself and/or the
   transport channel to avoid inadvertent disclosure of private data.

   It is also of the utmost importance the authentication of the
   parties passing data escrow deposit files. The escrow agent SHOULD
   properly authenticate the identity of the IIIN before accepting data
   escrow deposits. In a similar manner, the IIIN SHOULD authenticate
   the identity of the escrow agent before submitting any data.

   Additionally, the IIIN and the escrow agent SHOULD use integrity
   checking mechanisms to ensure the data transmitted is what the
   source intended.  Validation of the contents by the escrow agent is
   RECOMMENDED to ensure not only the file was transmitted correctly
   from the IIIN, but also the contents are also "meaningful".





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8. IANA Considerations

   This document uses URNs to describe XML namespaces and XML schemas
   conforming to a registry mechanism described in [RFC3688]. Two URI
   assignments need to be registered by the IANA.

   Registration request for the INDE namespace:

       URI: urn:ietf:params:xml:ns:inde-1.0

      Registrant Contact: See the "Author's Address" section of this
   document.

      XML: None.  Namespace URIs do not represent an XML specification.

   Registration request for the INDE XML schema:

      URI: urn:ietf:params:xml:schema:inde-1.0

      Registrant Contact: See the "Author's Address" section of this
   document.

      XML: See the "Formal Syntax" section of this document.

9. Privacy Considerations

   This specification defines a format that may be used to escrow
   personal data. The process of data escrow is governed by a legal
   document agreed by the parties, and such legal document must
   regulate the particularities regarding the protection of personal
   data.

10. References

10.1. Normative References

   [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>.
    [RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet:
              Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
              <https://www.rfc-editor.org/info/rfc3339>.
   [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>.



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10.2. Informative References

   [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.
  [RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing
             Architecture", RFC 4291, February 2006.
  [RFC5730] Hollenbeck, S., "Extensible Provisioning Protocol (EPP)",
             STD 69, RFC 5730, August 2009.
  [RFC2874] Crawford, M. and C. Huitema, "DNS Extensions to Support
             IPv6 Address Aggregation and Renumbering", RFC 2874,July
             2000.
  [RFC3596] Thomson, S., Huitema, C., Ksinant, V., and M. Souissi,
             "DNS Extensions to Support IP Version 6", RFC 3596,
             October 2003.
11. Acknowledgments

   This document reference draft [draft-ietf-regext-data-escrow-03],
   thus, would like to thank the draft author G. Lozano. And would like
   to thank X. Fan, J. Chen, C. Ma, M. Chen, Z. Li who provided special
   important suggestions and invaluable comments. This document was
   prepared using 2-Word-v2.0.template.dot.

Authors' Address

   Hongjie Wu
   CAICT
   No.52 Huayuan North Road, Haidian District
   Beijing, Beijing, 100191
   China

   Phone: +86 186 0106 5934
   Email: wuhongjie@caict.ac.cn


   Jian Chen
   CAICT
   No.52 Huayuan North Road, Haidian District
   Beijing, Beijing, 100191
   China

   Phone: +86 138 1103 3332
   Email: chenjian3@caict.ac.cn



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   Xiaotian Fan
   CAICT
   No.52 Huayuan North Road, Haidian District
   Beijing, Beijing, 100191
   China

   Phone: +86 134 0108 6945
   Email: fanxiaotian@caict.ac.cn


   Meilan Chen
   CAICT
   No.52 Huayuan North Road, Haidian District
   Beijing, Beijing, 100191
   China

   Phone: +86 139 1143 7301
   Email: chenmeilan@caict.ac.cn


   Zhiping Li
   CAICT
   No.52 Huayuan North Road, Haidian District
   Beijing, Beijing, 100191
   China

   Phone: +86 185 1107 1386
   Email: lizhiping@caict.ac.cn




















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