IPv6 Maintenance
Internet Engineering Task Force (IETF) L. Colitti
Internet-Draft
Request for Comments: 9762 J. Linkova
Updates: 4861, 4862 (if approved) X. Ma, Ed.
Intended status:
Category: Standards Track Google
Expires: 11 April 2025
ISSN: 2070-1721 D. Lamparter
NetDEF, Inc.
8 October 2024
March 2025
Signaling DHCPv6 Prefix Delegation per Client Availability to Hosts
draft-ietf-6man-pio-pflag-12
Abstract
This document defines a the "P" flag in the Prefix Information Option
(PIO) of IPv6 Router Advertisements (RAs). The flag is used to
indicate that the network prefers that clients use the RFC9663 deployment
model in RFC 9663 instead of using individual adresses addresses in the on-link on-
link prefix assigned using Stateless Address Autoconfiguration
(SLAAC) or DHCPv6 address assignment.
This document updates RFC4862 RFC 4862 to indicate that the Autonomous flag
in a PIO needs to be ignored if the PIO has the P flag set. It also
updates RFC4861 RFC 4861 to specify that the P flag indicates DHCPv6 Prefix
Delegation support for clients.
Status of This Memo
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provisions of BCP 78 and BCP 79.
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Internet Standards is available in Section 2 of six months RFC 7841.
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This Internet-Draft will expire on 11 April 2025.
https://www.rfc-editor.org/info/rfc9762.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . 4
5. P Flag Overview . . . . . . . . . . . . . . . . . . . . . . . 5
6. Router Behaviour . . . . . . . . . . . . . . . . . . . . . . 6 Behavior
7. Client Behaviour . . . . . . . . . . . . . . . . . . . . . . 6 Behavior
7.1. Processing the P Flag . . . . . . . . . . . . . . . . . . 6
7.2. Using Delegated Prefix(es) . . . . . . . . . . . . . . . 7
7.3. Absence of PIOs with the P bit set . . . . . . . . . . . . . 8 Bit Set
7.4. On-link On-Link Communication . . . . . . . . . . . . . . . . . . 8
7.5. Source Address Selection . . . . . . . . . . . . . . . . 9
8. Multihoming . . . . . . . . . . . . . . . . . . . . . . . . . 9
9. Modifications to RFC-Mandated Behaviour . . . . . . . . . . . 9 Behavior
9.1. Changes to RFC4861 . . . . . . . . . . . . . . . . . . . 9 RFC 4861
9.2. Changes to RFC4862 . . . . . . . . . . . . . . . . . . . 10 RFC 4862
10. Security Considerations . . . . . . . . . . . . . . . . . . . 11
11. Privacy Considerations . . . . . . . . . . . . . . . . . . . 12
12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
13.1. Normative References . . . . . . . . . . . . . . . . . . 12
13.2. Informative References . . . . . . . . . . . . . . . . . 13
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
[RFC9663] documents an IPv6 address assignment model where IPv6
devices obtain dedicated prefixes from the network via DHCPv6 Prefix
Delegation (DHCPv6-PD, [RFC8415]). (DHCPv6-PD) [RFC8415]. This model provides devices with a
large IPv6 address space they can use to create addresses for
communication, individually number virtual machines (VM)s (VMs) or
containers, or extend the network to downstream devices. It also
provides scalability benefits on large networks because network
infrastructure devices do not need to maintain per-address state,
such as IPv6 neighbor cache, Source Address Validation Improvement
(SAVI, [RFC7039])
(SAVI) [RFC7039] mappings, Virtual eXtensible Local Area Network
(VXLAN, [RFC7348])
(VXLAN) [RFC7348] routes, etc.
On networks with fewer devices, however, this model may not be
appropriate, because scaling to support multiple individual IPv6
addresses per device is less of a concern. Also, many home networks
currently offer prefix delegation but assume that a limited number of
specialized devices and/or applications will require delegated
prefixes,
prefixes and thus do not allocate enough address space to offer
prefixes to every device that connects to the network. For example,
if clients enable [RFC9663] on a home network that only receives a
/60 from the ISP, ISP and each client obtains a /64 prefix, then the
network will run out of prefixes after 15 devices have been
connected.
Therefore, to safely roll out [RFC9663] implementations on the client
side, it is necessary to have a mechanism for the network to signal
to the client which address assignment method is preferred.
2. Requirements Language
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.
3. Terminology
Node: a device that implements IPv6, [RFC8200]. IPv6 [RFC8200]
Host: any node that is not a router, [RFC8200]. router [RFC8200]
Client: a node which that connects to a network and acquires addresses.
The node may wish to obtain addresses for its own use, or it may
be a router that wishes to extend the network to its physical or
virtual subsystems, or both. It may be either a host or a router
as defined by [RFC8200].
DHCPv6-PD: DHCPv6 ([RFC8415]) Prefix Delegation [RFC8415]; a mechanism to
delegate IPv6 prefixes to clients.
DHCPv6 IA_NA: Identity Association for Non-temporary Addresses
(Section 21.4 of [RFC8415]). [RFC8415])
DHCPv6 IA_PD: Identity Association for Prefix Delegation
(Section 21.21 of [RFC8415]). [RFC8415])
ND: Neighbor Discovery, [RFC4861]. Discovery [RFC4861]
On-link address: an address that is assigned to an interface on a
specified link ([RFC4861]). [RFC4861]
On-link prefix: a prefix that is assigned to a specified link. link
Off-link: the opposite of "on-link" (see [RFC4861]). [RFC4861])
PIO: Prefix Information Option, [RFC4862]. Option [RFC4862]
SLAAC: IPv6 Stateless Address Autoconfiguration, [RFC4862]. Autoconfiguration [RFC4862]
4. Rationale
The network administrator might want to indicate to clients that
requesting a prefix via DHCPv6-PD and using that prefix for address
assignment (see [RFC9663]) should be preferred over using individual
addresses from the on-link prefix. The information is passed to the
client via a P flag in the Prefix Information Option (PIO). The
reason
reasons for it being a PIO flag is are as follows:
* The information must be contained in the Router Advertisement
because it must be available to the client before it decides to
form IPv6 addresses from the PIO prefix using SLAAC. Otherwise,
the client might use SLAAC to form IPv6 addresses from the PIO
provided and start using them, even if a unique per-client prefix
is available via DHCPv6-PD. Forming addresses via SLAAC is
suboptimal because if the client later acquires a prefix using
DHCPv6-PD, it can either 1) use both the prefix and SLAAC
addresses, reducing the scalability benefits of using DHCPv6-PD,
or can 2) remove the SLAAC addresses, which would be disruptive for
applications that are using them.
* This information is specific to the particular prefix being
announced. For example, a network administrator might want
clients to assign global addresses from delegated prefixes, prefixes but use
the PIO prefix to form Unique Local IPv6 Unicast (ULA, [RFC4193])
addresses. Addresses
[RFC4193]. Also, in a multihoming situation, one upstream network
might choose to assign prefixes via prefix delegation, delegation and another
via PIOs.
Note that setting the 'P' flag in a PIO expresses the network
operator's preference as to whether that clients should attempt using DHCPv6-PD
instead of performing individual address configuration on the prefix.
For clients that honor this preference by requesting prefix
delegation, the actual delegated prefix will necessarily be a prefix
different from the one from the PIO.
5. P Flag Overview
The P flag (also called the DHCPv6-PD preferred flag) is a 1-bit PIO
flag, located after the R flag ([RFC6275]). [RFC6275]. The presence of a PIO with
the P flag set indicates that the network prefers that clients use
Prefix Delegation instead of acquiring individual addresses via SLAAC
or DHCPv6 address assignment. This implies that the network has a
DHCPv6 server capable of making DHCPv6 Prefix Delegations to every
device on the network, as described in [RFC9663].
The
Figure 1 shows the resulting format of the Prefix Information Option is as follows
(see Figure 1): Option.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Prefix Length |L|A|R|P| Rsvd1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Valid Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Preferred Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Prefix +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1
The P flag is independent of the value of the M and O flags in the
Router Advertisement. If the network desires to delegate prefixes to
devices that support DHCPv6 Prefix Delegation but do not support the
P flag, it SHOULD also set the M or O bits in the RA to 1, because
some devices, such as [RFC7084] Customer Edge (CE) routers, routers [RFC7084], might not
initiate DHCPv6 Prefix Delegation if both the M and O bits are set to
zero.
6. Router Behaviour Behavior
Routers SHOULD set the P flag to zero by default, unless explicitly
configured by the administrator, and SHOULD allow the operator to set
the P flag value for any given prefix advertised in a PIO. Routers
MUST allow the P flag to be configured separately from the A flag.
In particular, enabling or disabling the P flag MUST not trigger
automatic changes in the A flag value set by the router.
7. Client Behaviour Behavior
7.1. Processing the P Flag
This specification only applies to clients which that support DHCPv6 Prefix
Delegation. Clients which that do not support DHCPv6 prefix delegation
MUST ignore the P flag. The P flag is meaningless for link-local prefixes
prefixes, and any Prefix Information Option containing the link-local
prefix MUST be ignored as specified in Section 5.5.3 of [RFC4862].
In the following text, all prefixes are assumed not to be link-local.
For each interface, the client MUST keep a list of every prefix that
was received from a PIO with the P flag set and currently has a non-
zero Preferred Lifetime. The list affects the behaviour behavior of the DHCPv6
client as follows:
* When a prefix's Preferred Lifetime becomes zero, either because
the Preferred Lifetime expires or because the client receives a
PIO for the prefix with a zero Preferred Lifetime, the prefix MUST
be removed from the list.
* When the length of the list increases to one, the client SHOULD
start requesting prefixes via DHCPv6 prefix delegation unless it
is already doing so.
* When the length of the list decreases to zero, the client SHOULD
stop requesting or renewing prefixes via DHCPv6 prefix delegation
if it has no other reason to do so. The lifetimes of any prefixes
already obtained via DHCPv6 are unaffected.
* If the client has already received delegated prefix(es) from one
or more servers, then any time a prefix is added to or removed
from the list, the client MUST consider this to be a change in
configuration information as described in Section 18.2.12 of
[RFC8415]. In that case case, the client MUST perform a REBIND, unless
the list is now empty. This is in addition to performing a REBIND
in the other cases required by that section. Issuing a REBIND
allows the client to obtain new prefixes if necessary, for example
example, when the network is being renumbered. It also refreshes
the state related to the delegated prefix(es).
When a client requests a prefix via DHCPv6-PD, it MUST use the prefix
length hint (Section 18.2.4 of [RFC8415]) to request a prefix that is
short enough to form addresses via SLAAC.
In order to achieve the scalability benefits of using DHCPv6-PD, the
client SHOULD prefer to form addresses from the delegated prefix
instead of using individual addresses in the on-link prefix(es).
Therefore, when the client requests a prefix using DHCPv6-PD, the
client SHOULD NOT use SLAAC to obtain IPv6 addresses from PIOs with
the P and A bits set. Similarly, if all PIOs processed by the client
have the P bit set, the client SHOULD NOT request individual IPv6
addresses from DHCPv6, i.e., it SHOULD NOT include any IA_NA options
in SOLICIT ([RFC8415]) messages. messages [RFC8415]. The client MAY continue to use
addresses that are already configured.
If the client does not obtain any suitable prefixes via DHCPv6-PD
that are suitable for SLAAC, it MAY choose to disable further
processing of the P flag on that interface, allowing the client to
fall back to other address assignment mechanisms, such as forming
addresses via SLAAC (if the PIO has the A flag set to 1) and/or
requesting individual addresses via DHCPv6.
7.2. Using Delegated Prefix(es)
If the delegated prefix is too long to be used for SLAAC, the client
MUST ignore it, as Section 7 of [RFC9663] requires the network to
provide a SLAAC-suitable prefix to clients. If the prefix is shorter
than required for SLAAC, the client SHOULD accept it, allocate one or
more longer prefix prefixes suitable for SLAAC SLAAC, and use the prefixes as
described below.
For every accepted prefix:
* The client MAY form as many IPv6 addresses from the prefix as it
chooses.
* The client MAY use the prefix to provide IPv6 addresses to
internal components such as virtual machines VMs or containers.
* The client MAY use the prefix to allow devices directly connected
to it to obtain IPv6 addresses. For example, the client MAY route
traffic for that prefix to the interface and send a Router
Advertisement containing a PIO for the prefix on the interface.
That interface MUST NOT be the interface the prefix is obtained
from. If the client advertises the prefix on an interface, interface and it
has formed addresses from the prefix, then it MUST act as though
the addresses were assigned to that interface for the purposes of
Neighbour
Neighbor Discovery and Duplicate Address Detection.
The client MUST NOT send or forward packets with destination
addresses within a delegated prefix to the interface that it obtained
the prefix on, as this can cause a routing loop. This problem will
not occur if the client has assigned the prefix to another interface.
Another way the client can prevent this problem is to add to its
routing table a high-metric discard route for the delegated prefix.
7.3. Absence of PIOs with the P bit set Bit Set
The P bit is purely a positive indicator, telling nodes that DHCPv6
Prefix Delegation is available and the network prefers that nodes use
it, even if they do not have any other reason to run a Prefix
Delegation client. The absence of any PIOs with the P bit does not
carry any kind of signal to the opposite, opposite and MUST NOT be processed to
mean that DHCPv6-PD is absent. In particular, nodes that run
DHCPv6-PD due to explicit configuration or by default (e.g., to
extend the network) MUST NOT disable DHCPv6-PD on the absence of PIOs
with the P bit set. A very common example of this are CE routers as
described by [RFC7084].
7.4. On-link On-Link Communication
When the network delegates unique prefixes to clients, each client
will consider other client's destination addresses to be off-link,
because those addresses are from the delegated prefixes and are not
within any on-link prefix. When a client sends traffic to another
client, packets will initially be sent to the default router. The
router may respond with an ICMPv6 redirect message (Section 4.5 of
[RFC4861]). If the client receives and accepts the redirect, then
traffic can flow directly from device to device. Therefore, hosts
supporting the P flag SHOULD process redirects unless configured
otherwise. Hosts which that do not process ICMPv6 redirects, and routers,
which routers
that do not act on ICMPv6 redirects, may experience higher latency
while communicating to prefixes delegated to other clients on the
same link.
7.5. Source Address Selection
For the purpose of source address selection [RFC6724], if the host
creates any addresses from a delegated prefix, it SHOULD treat those
addresses as if they were assigned to the interface on which the
prefix was received. This includes placing them in the candidate
set, set
and associating them with the outgoing interface when implementing
Rule 5 of the source address selection algorithm. algorithm [RFC6724].
8. Multihoming
In multi-prefix multihoming, the host generally needs to associate
the prefix with the router that advertised it (see for (for example,
[RFC6724] see Rule 5.5).
5.5 in [RFC6724]). If the host supports Rule 5.5, then it SHOULD
associate each prefix with the link-local address of the DHCPv6
server or relay from which it received the REPLY packet. When
receiving multiple REPLYs carrying the same prefix from distinct
link-local addresses, the host SHOULD associate that prefix with all
of these addresses. This can commonly happen in networks with
redundant routers and DHCPv6 servers or relays.
9. Modifications to RFC-Mandated Behaviour Behavior
9.1. Changes to RFC4861 RFC 4861
This document makes the following changes to Section 4.2 of
[RFC4861]:
OLD TEXT:
====
| Note: If neither M nor O flags are set, this indicates that no
| information is available via DHCPv6.
====
NEW TEXT:
====
| Note: If none of the M, O, or P (draft-ietf-6man-pio-pflag) (RFC 9762) flags are not set, this
| indicates that no information is available via DHCPv6.
====
9.2. Changes to RFC4862 RFC 4862
This document makes the following changes to Section 5.5.3 of
[RFC4862]:
OLD TEXT:
===
| For each Prefix-Information option in the Router Advertisement:
|
| a) If the Autonomous flag is not set, silently ignore the Prefix
| Information option.
|
| b) If the prefix is the link-local prefix, silently ignore the
| Prefix Information option.
|
| c) If the preferred lifetime is greater than the valid lifetime,
| silently ignore the Prefix Information option. A node MAY
| wish to log a system management error in this case.
|
| d) If the prefix advertised is not equal to the prefix of an
| address configured by stateless autoconfiguration already in
| the list of addresses associated with the interface (where
| "equal" means the two prefix lengths are the same and the
| first prefix- length prefix-length bits of the prefixes are identical), and
| if the Valid Lifetime is not 0, form an address (and add it to
| the list) by combining the advertised prefix with an interface
| identifier of the link as follows:
===
NEW TEXT:
===
| For each Prefix-Information option Prefix Information Option in the Router Advertisement:
|
| a) If the P flag is set, set and the node implements draft-ietf-6man-pio-
pflag, RFC 9762, it
| SHOULD treat the Autonomous flag as if it was unset, unset and use
| prefix delegation to obtain addresses as described in draft-ietf-
6man-pio-pflag. RFC
| 9762.
|
| b) If the Autonomous flag is not set, silently ignore the Prefix
| Information option. Option.
|
| c) If the prefix is the link-local prefix, silently ignore the
| Prefix Information option. Option.
|
| d) If the preferred lifetime is greater than the valid lifetime,
| silently ignore the Prefix Information option. Option. A node MAY
| wish to log a system management error in this case.
|
| e) If the prefix advertised is not equal to the prefix of an
| address configured by stateless autoconfiguration already in
| the list of addresses associated with the interface (where
| "equal" means the two prefix lengths are the same and the
| first prefix- length prefix-length bits of the prefixes are identical), identical) and if
| the Valid Lifetime is not 0, form an address (and add it to
| the list) by combining the advertised prefix with an interface
| identifier of the link as follows:
===
10. Security Considerations
The mechanism described in this document relies on the information
provided in the Router Advertisement and therefore shares the same
security model as SLAAC. If the network does not implement RA Guard RA-Guard
[RFC6105], an attacker might send RAs containing the PIO used by the
network, set the P flag to 1 1, and force hosts to ignore the A flag.
In the absence of DHCPv6-PD infrastructure, hosts would either obtain
no IPv6 addresses or, if they fall back to other IPv6 address
assignment mechanisms such as SLAAC and IA_NA, would experience
delays in obtaining IPv6 addresses. If the network does not support
DHCPv6-Shield [RFC7610], the attacker could also run a rogue DHCPv6
server, providing the host with invalid prefixes or other invalid
configuration information.
The attacker might force hosts to oscillate between DHCPv6-PD and
PIO-based SLAAC by sending the same set of PIOs with and then w/o without
the P flag set. That would cause the clients to issue REBIND
requests, increasing the load on the DHCP infrastructure. However,
Section 14.1 of [RFC8415] requires that DHCPv6-PD clients rate limit rate-limit
transmitted DHCPv6 messages.
It should be noted that if the network allows rogue RAs to be sent,
the attacker would be able to disrupt hosts connectivity anyway, so
this document doesn't introduce any fundamentally new security
considerations.
Security considerations inherent to the PD-per-device model are
documented in Section 15 of [RFC9663].
11. Privacy Considerations
The privacy implications of implementing the P flag and using
DHCPv6-PD to assign prefixes to hosts are similar to the privacy
implications of using DHCPv6 for assigning individual addresses. If
the DHCPv6 infrastructure assigns the same prefix to the same client,
then an observer might be able to identify clients based on the
highest 64 bits of the client's address. Those implications and
recommended countermeasures are discussed in Section 13 of [RFC9663].
Implementing the P flag support on a host / and receiving side enables
DHCPv6 on that host. Sending DHCPv6 packets may reveal some minor
additional information about the host, most prominently the hostname.
This is not a new concern and would apply for any network which that uses
DHCPv6 and sets the 'M' flag in Router Advertisements.
No privacy considerations result from supporting the P flag on the
sender side.
12. IANA Considerations
This memo requests that
IANA allocate bit 3 from has made the following allocation in the "IPv6 Neighbor
Discovery Prefix Information Option Flags" registry created by
[RFC8425] for use as the P flag as described in this document. The
following entry should be appended:
+================+==============================+=================+ [RFC8425]:
+================+==============================+===========+
| PIO Option Bit | Description | Reference |
+================+==============================+=================+
+================+==============================+===========+
| 3 | P - DHCPv6-PD preferred flag | [THIS DOCUMENT] RFC 9762 |
+----------------+------------------------------+-----------------+
+----------------+------------------------------+-----------+
Table 1
13. References
13.1. 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>.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
DOI 10.17487/RFC4861, September 2007,
<https://www.rfc-editor.org/info/rfc4861>.
[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862,
DOI 10.17487/RFC4862, September 2007,
<https://www.rfc-editor.org/info/rfc4862>.
[RFC6724] Thaler, D., Ed., Draves, R., Matsumoto, A., and T. Chown,
"Default Address Selection for Internet Protocol Version 6
(IPv6)", RFC 6724, DOI 10.17487/RFC6724, September 2012,
<https://www.rfc-editor.org/info/rfc6724>.
[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>.
[RFC8425] Troan, O., "IANA Considerations for IPv6 Neighbor
Discovery Prefix Information Option Flags", RFC 8425,
DOI 10.17487/RFC8425, July 2018,
<https://www.rfc-editor.org/info/rfc8425>.
13.2. Informative References
[RFC4193] Hinden, R. and B. Haberman, "Unique Local IPv6 Unicast
Addresses", RFC 4193, DOI 10.17487/RFC4193, October 2005,
<https://www.rfc-editor.org/info/rfc4193>.
[RFC6105] Levy-Abegnoli, E., Van de Velde, G., Popoviciu, C., and J.
Mohacsi, "IPv6 Router Advertisement Guard", RFC 6105,
DOI 10.17487/RFC6105, February 2011,
<https://www.rfc-editor.org/info/rfc6105>.
[RFC6275] Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility
Support in IPv6", RFC 6275, DOI 10.17487/RFC6275, July
2011, <https://www.rfc-editor.org/info/rfc6275>.
[RFC7084] Singh, H., Beebee, W., Donley, C., and B. Stark, "Basic
Requirements for IPv6 Customer Edge Routers", RFC 7084,
DOI 10.17487/RFC7084, November 2013,
<https://www.rfc-editor.org/info/rfc7084>.
[RFC7039] Wu, J., Bi, J., Bagnulo, M., Baker, F., and C. Vogt, Ed.,
"Source Address Validation Improvement (SAVI) Framework",
RFC 7039, DOI 10.17487/RFC7039, October 2013,
<https://www.rfc-editor.org/info/rfc7039>.
[RFC7084] Singh, H., Beebee, W., Donley, C., and B. Stark, "Basic
Requirements for IPv6 Customer Edge Routers", RFC 7084,
DOI 10.17487/RFC7084, November 2013,
<https://www.rfc-editor.org/info/rfc7084>.
[RFC7348] Mahalingam, M., Dutt, D., Duda, K., Agarwal, P., Kreeger,
L., Sridhar, T., Bursell, M., and C. Wright, "Virtual
eXtensible Local Area Network (VXLAN): A Framework for
Overlaying Virtualized Layer 2 Networks over Layer 3
Networks", RFC 7348, DOI 10.17487/RFC7348, August 2014,
<https://www.rfc-editor.org/info/rfc7348>.
[RFC7610] Gont, F., Liu, W., and G. Van de Velde, "DHCPv6-Shield:
Protecting against Rogue DHCPv6 Servers", BCP 199,
RFC 7610, DOI 10.17487/RFC7610, August 2015,
<https://www.rfc-editor.org/info/rfc7610>.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
[RFC9663] Colitti, L., Linkova, J., Ed., and X. Ma, Ed., "Using
DHCPv6 Prefix Delegation (DHCPv6-PD) to Allocate Unique
IPv6 Prefixes per Client in Large Broadcast Networks",
RFC 9663, DOI 10.17487/RFC9663, October 2024,
<https://www.rfc-editor.org/info/rfc9663>.
Acknowledgements
Thanks to Nick Buraglio, Brian Carpenter, Tim Chown, David Farmer,
Fernando Gont, Susan Hares, Dirk Von Hugo, Mahesh Jethanandani, Suresh Krishnan, Ted
Lemon, Andrew McGregor, Erik Nordmark, Tomek Mrugalski, Erik Nordmark, Michael
Richardson, John Scudder, Ole Trøan, Eric Dirk Von Hugo, Éric Vyncke and
Timothy Winters for the discussions, reviews, the input input, and all
contributions.
Authors' Addresses
Lorenzo Colitti
Google
Shibuya 3-21-3,
Japan
Email: lorenzo@google.com
Jen Linkova
Google
1 Darling Island Rd
Pyrmont NSW 2009
Australia
Email: furry13@gmail.com, furry@google.com
Xiao Ma (editor)
Google
Shibuya 3-21-3,
Japan
Email: xiaom@google.com
David 'equinox' Lamparter
NetDEF, Inc.
San Jose,
United States of America
04229 Leipzig
Germany
Email: equinox@diac24.net, equinox@opensourcerouting.org