Homenet                                                       D. Migault
Internet-Draft                                                  Ericsson
Intended status: Standards Track                                R. Weber
Expires: October 30, 2021                                         Akamai
                                                            T. Mrugalski
                                       Internet Systems Consortium, Inc.
                                                          April 28, 2021


            DHCPv6 Options for Home Network Naming Authority
         draft-ietf-homenet-naming-architecture-dhc-options-12

Abstract

   This document defines DHCPv6 options so an agnostic Homenet Naming
   Authority (HNA) can automatically proceed to the appropriate
   configuration and outsource the authoritative naming service for the
   home network.  In most cases, the outsourcing mechanism is
   transparent for the end user.

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
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   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
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   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 October 30, 2021.

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
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   to this document.  Code Components extracted from this document must



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   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.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Protocol Overview . . . . . . . . . . . . . . . . . . . . . .   3
   4.  Payload Description . . . . . . . . . . . . . . . . . . . . .   4
     4.1.  Registered Homenet Domain Option  . . . . . . . . . . . .   4
     4.2.  Distribution Master Option  . . . . . . . . . . . . . . .   5
       4.2.1.  Supported Transport . . . . . . . . . . . . . . . . .   6
     4.3.  Reverse Distribution Master Server Option . . . . . . . .   6
   5.  DHCP Behavior . . . . . . . . . . . . . . . . . . . . . . . .   7
     5.1.  DHCPv6 Server Behavior  . . . . . . . . . . . . . . . . .   7
     5.2.  DHCPv6 Client Behavior  . . . . . . . . . . . . . . . . .   7
     5.3.  DHCPv6 Relay Agent Behavior . . . . . . . . . . . . . . .   7
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   7
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .   8
   8.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .   8
   9.  Contributors  . . . . . . . . . . . . . . . . . . . . . . . .   8
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .   8
     10.1.  Normative References . . . . . . . . . . . . . . . . . .   8
     10.2.  Informative References . . . . . . . . . . . . . . . . .   9
   Appendix A.  Scenarios and impact on the End User . . . . . . . .  11
   Appendix B.  Base Scenario  . . . . . . . . . . . . . . . . . . .  11
     B.1.  Third Party Registered Homenet Domain . . . . . . . . . .  11
     B.2.  Third Party DNS Infrastructure  . . . . . . . . . . . . .  12
     B.3.  Multiple ISPs . . . . . . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Terminology

   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.

   The reader is expected to be familiar with
   [I-D.ietf-homenet-front-end-naming-delegation] and its terminology
   section.








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2.  Introduction

   [I-D.ietf-homenet-front-end-naming-delegation] specifies how an
   entity designated as the Homenet Naming Authority (HNA) outsources a
   Public Homenet Zone to an Outsourcing DNS Infrastructure (DOI).

   This document shows how an ISP can provision automatically the HNA
   with a specific DOI.  Most likely the DOI will be - at least partly
   be - managed or provided by its ISP, but other cases may envision the
   ISP storing some configuration so the homenet becomes resilient to
   HNA replacement.

   The ISP delegates the home network an IP prefix it owns as well as
   the associated reverse zone.  The ISP is well aware of the owner of
   that prefix, and as such becomes a natural candidate for hosting the
   Homenet Reverse Zone - that is the Reverse Distribution Master (RDM)
   and potentially the Reverse Public Authoritative Servers.

   In addition, the ISP often identifies the home network with a name.
   In most cases, the name is used by the ISP for its internal network
   management operations and is not a name the home network owner has
   registered to.  The ISP may thus leverage such infrastructure and
   provide the homenet a specific domain name designated as per
   [I-D.ietf-homenet-front-end-naming-delegation] a Homenet Registered
   Domain.  Similarly to the reverse zone, the ISP is well aware of who
   owns that domain name and may become a natural candidate for hosting
   the Homenet Zone - that is the Distribution Master (DM) and the
   Public Authoritative Servers.

   This document describes DHCPv6 options that enables the ISP to
   provide the necessary parameters to the HNA, to proceed.  More
   specifically, the ISP provides the Registered Homenet Domain,
   necessary information on the DM and the RDM so the HNA can manage and
   upload the Public Homenet Zone and the Reverse Public Homenet Zone as
   described in [I-D.ietf-homenet-front-end-naming-delegation].

   The use of DHCPv6 options makes the configuration completely
   transparent to the end user and provides a similar level of trust as
   the one used to provide the IP prefix.

3.  Protocol Overview

   This section illustrates how a HNA receives the necessary information
   via DHCPv6 options to outsource its authoritative naming service to
   the DOI.  For the sake of simplicity, and similarly to
   [I-D.ietf-homenet-front-end-naming-delegation], this section assumes
   that the HNA and the home network DHCPv6 client are collocated on the
   CPE.  Note also that this is not mandatory and specific



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   communications between the HNA and the DHCPv6 client only are needed.
   In addition, this section assumes the responsible entity for the
   DHCPv6 server is able to configure the DM and RDM.  In our case, this
   means a Registered Homenet Domain can be associated to the DHCP
   client.

   This scenario has been chosen as it is believed to be the most
   popular scenario.  This document does not ignore scenarios where the
   DHCP Server does not have privileged relations with the DM or RDM.
   These cases are discussed latter in Appendix A.  Such scenarios do
   not necessarily require configuration for the end user and can also
   be zero-config.

   The scenario considered in this section is as follows:

   1.  The HNA is willing to outsource the Public Homenet Zone or
       Homenet Reverse Zone and configures its DHCP Client to include in
       its Option Request Option (ORO) the Registered Homenet Domain
       Option (OPTION_REGISTERED_DOMAIN), the Distribution Master Option
       (OPTION_DIST_MASTER) and the Reverse Distribution Master Option
       (OPTION_REVERSE_DIST_MASTER) option codes.

   2.  The DHCP Server responds to the HNA with the requested DHCPv6
       options based on the identified homenet.  The DHCP Client
       transmits the information to the HNA.

   3.  The HNA is able to get authenticated by the DM and the RDM.  The
       HNA builds the Homenet Zone ( resp. the Homenet Reverse Zone) and
       proceed as described in
       [I-D.ietf-homenet-front-end-naming-delegation].  The DHCPv6
       options provide the necessary and non optional parameters
       described in section 14 of
       [I-D.ietf-homenet-front-end-naming-delegation].  The HNA MAY set
       complement the configurations with additional parameters.
       Section 14 of [I-D.ietf-homenet-front-end-naming-delegation]
       describes such parameters that MAY take a default value.

4.  Payload Description

   This section details the payload of the DHCPv6 options.

4.1.  Registered Homenet Domain Option

   The Registered Domain Option (OPTION_REGISTERED_DOMAIN) indicates the
   FQDN associated to the home network.






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    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   OPTION_REGISTERED_DOMAIN    |         option-len            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   /                   Registered Homenet Domain                   /
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    Figure 1: Registered Domain Option

   o  option-code (16 bits): OPTION_REGISTERED_DOMAIN, the option code
      for the Registered Homenet Domain (TBD2).

   o  option-len (16 bits): length in octets of the option-data field as
      described in [RFC8415].

   o  Registered Homenet Domain (variable): the FQDN registered for the
      homenet encoded as described in section 10 of [RFC8415].

4.2.  Distribution Master Option

   The Distributed Master Option (OPTION_DIST_MASTER) provides the HNA
   to FQDN of the DM as well as the transport protocol for the
   transaction between the HNA and the DM.

    0                   1                        2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |      OPTION_DIST_MASTER       |          option-len           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Supported Transport       |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               |
   |                                                               |
   /                   Distribution Master  FQDN                   /
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                   Figure 2: Distribution Master Option

   o  option-code (16 bits): OPTION_DIST_MASTER, the option code for the
      DM Option (TBD3).

   o  option-len (16 bits): length in octets of the option-data field as
      described in [RFC8415].





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   o  Supported Transport (16 bits): defines the supported transport by
      the DM.  Each bit represents a supported transport, and a DM MAY
      indicate the support of multiple modes.  The bit for DNS over TLS
      [RFC7858] MUST be set.

   o  Distribution Master FQDN (variable): the FQDN of the DM encoded as
      described in section 10 of [RFC8415].

4.2.1.  Supported Transport

   The Supported Transport filed of the DHCPv6 option indicates the
   supported transport protocol.  Each bit represents a specific
   transport mechanism.  The bit sets to 1 indicates the associated
   transport protocol is supported.  The corresponding bits are assigned
   as described in Figure 3.

   Bit | Transport Protocol | Reference
   ----+--------------------+-----------
    0  | DNS over TLS       | This-RFC
   1-15| unallocated        |

                       Figure 3: Supported Transport

   o  DNS over TLS: indicates the support of DNS over TLS as described
      in [RFC7858].

4.3.  Reverse Distribution Master Server Option

   The Reverse Distribution Master Server Option
   (OPTION_REVERSE_DIST_MASTER) provides the HNA to FQDN of the DM as
   well as the transport protocol for the transaction between the HNA
   and the DM.

    0                   1                        2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | OPTION_REVERSE_DIST_MASTER    |          option-len           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Supported Transport       |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               |
   |                                                               |
   /               Reverse Distribution Master FQDN                /
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


               Figure 4: Reverse Distribution Master Option




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   o  option-code (16 bits): OPTION_REVERSE_DIST_MASTER, the option code
      for the Reverse Distribution Master Option (TBD4).

   o  option-len (16 bits): length in octets of the option-data field as
      described in [RFC8415].

   o  Supported Transport (16 bits): defines the supported transport by
      the DM.  Each bit represents a supported transport, and a DM MAY
      indicate the support of multiple modes.  The bit for DoT MUST be
      set.

   o  Reverse Distribution Master FQDN (variable): the FQDN of the RDM
      encoded as described in section 10 of [RFC8415].

5.  DHCP Behavior

5.1.  DHCPv6 Server Behavior

   Sections 17.2.2 and 18.2 of [RFC8415] govern server operation in
   regards to option assignment.  As a convenience to the reader, we
   mention here that the server will send option foo only if configured
   with specific values for foo and if the client requested it.  In
   particular, when configured the DHCP Server sends the Registered
   Homenet Domain Option, Distribution Master Option, the Reverse
   Distribution Master Option when requested by the DHCPv6 client by
   including necessary option codes in its ORO.

5.2.  DHCPv6 Client Behavior

   The DHCPv6 client sends a ORO with the necessary option codes:
   Registered Homenet Domain Option, Distribution Master Option, the
   Reverse Distribution Master Option.

   Upon receiving a DHCP option described in this document in the Reply
   message, the HNA SHOULD proceed as described in
   [I-D.ietf-homenet-front-end-naming-delegation].

5.3.  DHCPv6 Relay Agent Behavior

   There are no additional requirements for the DHCP Relay agents.

6.  IANA Considerations

   IANA is requested to assign the following new DHCPv6 Option Codes in
   the registry maintained in: https://www.iana.org/assignments/dhcpv6-
   parameters/dhcpv6-parameters.xhtml#dhcpv6-parameters-2.





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   Value Description                   Client ORO     Singleton Option
   TBD1  OPTION_REGISTERED_DOMAIN      Yes            Yes
   TBD2  OPTION_DIST_MASTER            Yes            Yes
   TBD3  OPTION_REVERSE_DIST_MASTER    Yes            Yes

   IANA is requested to maintain a new number space of Supported
   Transport parameter in the Distributed Master Option
   (OPTION_DIST_MASTER) or the Reverse Distribution Master Server Option
   (OPTION_REVERSE_DIST_MASTER).  The different parameters are defined
   in Figure 3 in Section 4.2.1.  Future code points are assigned under
   Specification Required as per [RFC8126].

7.  Security Considerations

   The security considerations in [RFC2131] and [RFC8415] are to be
   considered.  The use of DHCPv6 options provides a similar level of
   trust as the one used to provide the IP prefix.  The link between the
   HNA and the DHCPv6 server may benefit from additional security for
   example by using [I-D.ietf-dhc-sedhcpv6].

8.  Acknowledgments

   We would like to thank Marcin Siodelski, Bernie Volz and Ted Lemon
   for their comments on the design of the DHCPv6 options.  We would
   also like to thank Mark Andrews, Andrew Sullivan and Lorenzo Colliti
   for their remarks on the architecture design.  The designed solution
   has been largely been inspired by Mark Andrews's document
   [I-D.andrews-dnsop-pd-reverse] as well as discussions with Mark.  We
   also thank Ray Hunter for its reviews, its comments and for
   suggesting an appropriated terminology.

9.  Contributors

   The co-authors would like to thank Chris Griffiths and Wouter
   Cloetens that provided a significant contribution in the early
   versions of the document.

10.  References

10.1.  Normative References

   [RFC1034]  Mockapetris, P., "Domain names - concepts and facilities",
              STD 13, RFC 1034, DOI 10.17487/RFC1034, November 1987,
              <https://www.rfc-editor.org/info/rfc1034>.







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   [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>.

   [RFC2131]  Droms, R., "Dynamic Host Configuration Protocol",
              RFC 2131, DOI 10.17487/RFC2131, March 1997,
              <https://www.rfc-editor.org/info/rfc2131>.

   [RFC2181]  Elz, R. and R. Bush, "Clarifications to the DNS
              Specification", RFC 2181, DOI 10.17487/RFC2181, July 1997,
              <https://www.rfc-editor.org/info/rfc2181>.

   [RFC6672]  Rose, S. and W. Wijngaards, "DNAME Redirection in the
              DNS", RFC 6672, DOI 10.17487/RFC6672, June 2012,
              <https://www.rfc-editor.org/info/rfc6672>.

   [RFC7858]  Hu, Z., Zhu, L., Heidemann, J., Mankin, A., Wessels, D.,
              and P. Hoffman, "Specification for DNS over Transport
              Layer Security (TLS)", RFC 7858, DOI 10.17487/RFC7858, May
              2016, <https://www.rfc-editor.org/info/rfc7858>.

   [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <https://www.rfc-editor.org/info/rfc8126>.

   [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>.

   [RFC8415]  Mrugalski, T., Siodelski, M., Volz, B., Yourtchenko, A.,
              Richardson, M., Jiang, S., Lemon, T., and T. Winters,
              "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)",
              RFC 8415, DOI 10.17487/RFC8415, November 2018,
              <https://www.rfc-editor.org/info/rfc8415>.

10.2.  Informative References

   [I-D.andrews-dnsop-pd-reverse]
              Andrews, M., "Automated Delegation of IP6.ARPA reverse
              zones with Prefix Delegation", draft-andrews-dnsop-pd-
              reverse-02 (work in progress), November 2013.

   [I-D.ietf-dhc-sedhcpv6]
              Li, L., Jiang, S., Cui, Y., Jinmei, T., Lemon, T., and D.
              Zhang, "Secure DHCPv6", draft-ietf-dhc-sedhcpv6-21 (work
              in progress), February 2017.



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   [I-D.ietf-homenet-front-end-naming-delegation]
              Migault, D., Weber, R., Richardson, M., Hunter, R.,
              Griffiths, C., and W. Cloetens, "Simple Provisioning of
              Public Names for Residential Networks", draft-ietf-
              homenet-front-end-naming-delegation-13 (work in progress),
              March 2021.

   [I-D.sury-dnsext-cname-dname]
              Sury, O., "CNAME+DNAME Name Redirection", draft-sury-
              dnsext-cname-dname-00 (work in progress), April 2010.









































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Appendix A.  Scenarios and impact on the End User

   This section details various scenarios and discuss their impact on
   the end user.  This section is not normative and limits the
   description of a limited scope of scenarios that are assumed to be
   representative.  Many other scenarios may be derived from these.

Appendix B.  Base Scenario

   The base scenario is the one described in Section 3 in which an ISP
   manages the DHCP Server, the DM and RDM.

   The end user subscribes to the ISP (foo), and at subscription time
   registers for example.foo as its Registered Homenet Domain
   example.foo.

   In this scenario, the DHCP Server, DM and RDM are managed by the ISP
   so the DHCP Server and as such can provide authentication credentials
   of the HNA to enable secure authenticated transaction with the DM and
   the Reverse DM.

   The main advantage of this scenario is that the naming architecture
   is configured automatically and transparently for the end user.  The
   drawbacks are that the end user uses a Registered Homenet Domain
   managed by the ISP and that it relies on the ISP naming
   infrastructure.

B.1.  Third Party Registered Homenet Domain

   This section considers the case when the end user wants its home
   network to use example.com not managed by her ISP (foo) as a
   Registered Homenet Domain.  This section still consider the ISP
   manages the home network and still provides example.foo as a
   Registered Homenet Domain.

   When the end user buys the domain name example.com, it may request to
   redirect the name example.com to example.foo using static redirection
   with CNAME [RFC2181], [RFC1034], DNAME [RFC6672] or CNAME+DNAME
   [I-D.sury-dnsext-cname-dname].

   This configuration is performed once when the domain name example.com
   is registered.  The only information the end user needs to know is
   the domain name assigned by the ISP.  Once this configuration is done
   no additional configuration is needed anymore.  More specifically,
   the HNA may be changed, the zone can be updated as in Appendix B
   without any additional configuration from the end user.





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   The main advantage of this scenario is that the end user benefits
   from the Zero Configuration of the Base Scenario Appendix B.  Then,
   the end user is able to register for its home network an unlimited
   number of domain names provided by an unlimited number of different
   third party providers.  The drawback of this scenario may be that the
   end user still rely on the ISP naming infrastructure.  Note that the
   only case this may be inconvenient is when the DNS Servers provided
   by the ISPs results in high latency.

B.2.  Third Party DNS Infrastructure

   This scenario considers that the end user uses example.com as a
   Registered Homenet Domain, and does not want to rely on the
   authoritative servers provided by the ISP.

   In this section we limit the outsourcing to the DM and Public
   Authoritative Server(s) to a third party.  The Reverse Public
   Authoritative Server(s) and the RDM remain managed by the ISP as the
   IP prefix is managed by the ISP.

   Outsourcing to a third party DM can be performed in the following
   ways:

   1.  Updating the DHCP Server Information.  One can imagine a GUI
       interface that enables the end user to modify its profile
       parameters.  Again, this configuration update is done once-for-
       ever.

   2.  Upload the configuration of the DM to the HNA.  In some cases,
       the provider of the CPE hosting the HNA may be the registrar and
       provide the CPE already configured.  In other cases, the CPE may
       request the end user to log into the registrar to validate the
       ownership of the Registered Homenet Domain and agree on the
       necessary credentials to secure the communication between the HNA
       and the DM.  As described in
       [I-D.ietf-homenet-front-end-naming-delegation], such settings
       could be performed in an almost automatic way as to limit the
       necessary interactions with the end user.

B.3.  Multiple ISPs

   This scenario considers a HNA connected to multiple ISPs.

   Suppose the HNA has been configured each of its interfaces
   independently with each ISPS as described in Appendix B.  Each ISP
   provides a different Registered Homenet Domain.





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   The protocol and DHCPv6 options described in this document are fully
   compatible with a HNA connected to multiple ISPs with multiple
   Registered Homenet Domains.  However, the HNA should be able to
   handle different Registered Homenet Domains.  This is an
   implementation issue which is outside the scope of the current
   document.

   If a HNA is not able to handle multiple Registered Homenet Domains,
   the HNA may remain connected to multiple ISP with a single Registered
   Homenet Domain.  In this case, one entity is chosen to host the
   Registered Homenet Domain.  This entity may be one of the ISP or a
   third party.  Note that having multiple ISPs can be motivated for
   bandwidth aggregation, or connectivity fail-over.  In the case of
   connectivity fail-over, the fail-over concerns the access network and
   a failure of the access network may not impact the core network where
   the DM Server and Public Authoritative Primaries are hosted.  In that
   sense, choosing one of the ISP even in a scenario of multiple ISPs
   may make sense.  However, for sake of simplicity, this scenario
   assumes that a third party has been chosen to host the Registered
   Homenet Domain.  Configuration is performed as described in
   Appendix B.1 and Appendix B.2.

   With the configuration described in Appendix B.1, the HNA is expect
   to be able to handle multiple Homenet Registered Domain, as the third
   party redirect to one of the ISPs Servers.  With the configuration
   described in Appendix B.2, DNS zone are hosted and maintained by the
   third party.  A single DNS(SEC) Homenet Zone is built and maintained
   by the HNA.  This latter configuration is likely to match most HNA
   implementations.

   The protocol and DHCPv6 options described in this document are fully
   compatible with a HNA connected to multiple ISPs.  To configure or
   not and how to configure the HNA depends on the HNA facilities.
   Appendix B and Appendix B.1 require the HNA to handle multiple
   Registered Homenet Domain, whereas Appendix B.2 does not have such
   requirement.

Authors' Addresses

   Daniel Migault
   Ericsson
   8275 Trans Canada Route
   Saint Laurent, QC  4S 0B6
   Canada

   EMail: daniel.migault@ericsson.com





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Internet-Draft           DHCPv6 Options for HNA               April 2021


   Ralf Weber
   Akamai

   EMail: ralf.weber@akamai.com


   Tomek Mrugalski
   Internet Systems Consortium, Inc.
   950 Charter Street
   Redwood City  94063
   US

   EMail: tomasz.mrugalski@gmail.com






































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