V6OPS Working Group P. Matthews
Internet-Draft Alcatel-Lucent
Intended status: Informational V. Kuarsingh
Expires: August 26, 2015 Dyn
February 22, 2015
Some Design Choices for IPv6 Networks
draft-ietf-v6ops-design-choices-05
Abstract
This document presents advice on certain routing-related design
choices that arise when designing IPv6 networks (both dual-stack and
IPv6-only). The intended audience is someone designing an IPv6
network who is knowledgeable about best current practices around IPv4
network design, and wishes to learn the corresponding practices for
IPv6.
Status of This Memo
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provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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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 August 26, 2015.
Copyright Notice
Copyright (c) 2015 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
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to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Design Choices . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Interfaces . . . . . . . . . . . . . . . . . . . . . . . 3
2.1.1. Mix IPv4 and IPv6 on the Same Layer-3 Interface? . . 3
2.1.2. Interfaces with Only Link-Local Addresses? . . . . . 4
2.2. Static Routes . . . . . . . . . . . . . . . . . . . . . . 6
2.2.1. Link-Local Next-Hop in a Static Route? . . . . . . . 6
2.3. IGPs . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3.1. IGP Choice . . . . . . . . . . . . . . . . . . . . . 7
2.4. BGP . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.4.1. Which Transport for Which Routes? . . . . . . . . . . 8
2.4.1.1. BGP Sessions for Unlabeled Routes . . . . . . . . 10
2.4.1.2. BGP sessions for Labeled or VPN Routes . . . . . 11
2.4.2. eBGP Endpoints: Global or Link-Local Addresses? . . . 11
3. General Observations . . . . . . . . . . . . . . . . . . . . 12
3.1. Use of Link-Local Addresses . . . . . . . . . . . . . . . 12
3.2. Separation of IPv4 and IPv6 . . . . . . . . . . . . . . . 13
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
5. Security Considerations . . . . . . . . . . . . . . . . . . . 14
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
7. Informative References . . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
This document discusses certain choices that arise when designing a
IPv6-only or dual-stack network. The focus is on routing-related
design choices that do not usually come up when designing an
IPv4-only network. The document presents each choice and the
alternatives, and then discusses the pros and cons of the
alternatives in detail. Where consensus currently exists around the
best practice, this is documented; otherwise the document simply
summarizes the current state of the discussion. Thus this document
serves to both document the reasoning behind best current practices
for IPv6, and to allow a designer to make an informed choice where no
such consensus exists.
This document does not present advice on strategies for adding IPv6
to a network, nor does it discuss transition mechanisms. For advice
in these areas, see [RFC6180] for general advice, [RFC6782] for
wireline service providers, [RFC6342] for mobile network providers,
[RFC5963] for exchange point operators, [RFC6883] for content
providers, and both [RFC4852] and [RFC7381] for enterprises. Nor
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does this document discuss the particulars of creating an IPv6
addressing plan; for advice in this area, see [RFC5375] or
[v6-addressing-plan]. The details of ULA usage is also not
discussed; for this the reader is referred to
[I-D.ietf-v6ops-ula-usage-recommendations].
Finally, this document focuses on unicast routing design only and
does not cover multicast or the issues involved in running MPLS over
IPv6 transport.
2. Design Choices
Each subsection below presents a design choice and discusses the pros
and cons of the various options. If there is consensus in the
industry for a particular option, then the consensus position is
noted.
2.1. Interfaces
2.1.1. Mix IPv4 and IPv6 on the Same Layer-3 Interface?
If a network is going to carry both IPv4 and IPv6 traffic, as many
networks do today, then a fundamental question arises: Should an
operator mix IPv4 and IPv6 traffic or keep them separated? More
specifically, should the design:
a. Mix IPv4 and IPv6 traffic on the same layer-3 interface, OR
b. Separate IPv4 and IPv6 by using separate interfaces (e.g., two
physical links or two VLANs on the same link)?
Option (a) implies a single layer-3 interface at each end of the
connection with both IPv4 and IPv6 addresses; while option (b)
implies two layer-3 interfaces at each end, one for IPv4 addresses
and one with IPv6 addresses.
The advantages of option (a) include:
o Requires only half as many layer 3 interfaces as option (b), thus
providing better scaling;
o May require fewer physical ports, thus saving money;
o Can make the QoS implementation much easier (for example, rate-
limiting the combined IPv4 and IPv6 traffic to or from a
customer);
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o Works well in practice, as any increase in IPv6 traffic is usually
counter-balanced by a corresponding decrease in IPv4 traffic to or
from the same host (ignoring the common pattern of an overall
increase in Internet usage);
o And is generally conceptually simpler.
For these reasons, there is a relatively strong consensus in the
operator community that option (a) is the preferred way to go. Most
networks today use option (a) wherever possible.
However, there can be times when option (b) is the pragmatic choice.
Most commonly, option (b) is used to work around limitations in
network equipment. One big example is the generally poor level of
support today for individual statistics on IPv4 traffic vs IPv6
traffic when option (a) is used. Other, device-specific, limitations
exist as well. It is expected that these limitations will go away as
support for IPv6 matures, making option (b) less and less attractive
until the day that IPv4 is finally turned off.
2.1.2. Interfaces with Only Link-Local Addresses?
As noted in the introduction, this document does not cover the ins
and outs around creating an IPv6 addressing plan. However, there is
one fundamental question in this area that often arises: Should the
interface:
a. Use only link-local addresses ("unnumbered"), OR
b. Have global and/or unique-local) addresses assigned in addition
to link-locals?
There are two advantages of unnumbered interfaces. The first
advantage is ease of configuration. In a network with a large number
of unnumbered interfaces, the operator can just enable an IGP on each
router, without going through the tedious process of assigning and
tracking the addresses for each interface. The second advantage is
security. Since packets with link-local destination addresses should
not be routed, it is very difficult to attack the associated
interfaces from an off-link device. This implies less effort around
maintaining security ACLs.
Countering this advantage are various disadvantages to unnumbered
interfaces in IPv6:
o It is not possible to ping an interface that has only a link-local
address from a device that is not directly attached to the link.
Thus, to troubleshoot, one must typically log into a device that
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is directly attached to the device in question, and execute the
ping from there.
o A traceroute passing over the unnumbered link will return the
loopback or system address of the router, rather than the address
of the interface itself.
o In cases of parallel point to point links it is difficult to
determine which of the parallel links was taken when attempting to
troubleshoot unless one sends packets directly between the two
attached link-locals on the specific interfaces. Since many
network problems behave differently for traffic to/from a router
than for traffic through the router(s) in question, this can pose
a significant hurdle to some troubleshooting scenarios.
o On some routers, by default the link-layer address of the
interface is derived from the MAC address assigned to interface.
When this is done, swapping out the interface hardware (e.g.
interface card) will cause the link-layer address to change. In
some cases (peering config, ACLs, etc) this may require additional
changes. However, many devices allow the link-layer address of an
interface to be explicitly configured, which avoids this issue.
This problem should fade away over time as more and more routers
select interface identifiers according to the rules in [RFC7217].
o The practice of naming router interfaces using DNS names is
difficult and not recommended when using link-locals only. More
generally, it is not recommended to put link-local addresses into
DNS; see [RFC4472].
o It is often not possible to identify the interface or link (in a
database, email, etc) by giving just its address without also
specifying the link in some manner.
It should be noted that it is quite possible for the same link-local
address to be assigned to multiple interfaces. This can happen
because the MAC address is duplicated (due to manufacturing process
defaults or the use of virtualization), because a device deliberately
re-uses automatically-assigned link-local addresses on different
links, or because an operator manually assigns the same easy-to-type
link-local address to multiple interfaces. All these are allowed in
IPv6 as long as the addresses are used on different links.
For more discussion on the pros and cons, see [RFC7404]. See also
[RFC5375] for IPv6 unicast address assignment considerations.
Today, most operators use numbered interfaces (option b).
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2.2. Static Routes
2.2.1. Link-Local Next-Hop in a Static Route?
For the most part, the use of static routes in IPv6 parallels their
use in IPv4. There is, however, one exception, which revolves around
the choice of next-hop address in the static route. Specifically,
should an operator:
a. Use the far-end's link-local address as the next-hop address, OR
b. Use the far-end's GUA/ULA address as the next-hop address?
Recall that the IPv6 specs for OSPF [RFC5340] and ISIS [RFC5308]
dictate that they always use link-locals for next-hop addresses. For
static routes, [RFC4861] section 8 says:
A router MUST be able to determine the link-local address for each
of its neighboring routers in order to ensure that the target
address in a Redirect message identifies the neighbor router by
its link-local address. For static routing, this requirement
implies that the next-hop router's address should be specified
using the link-local address of the router.
This implies that using a GUA or ULA as the next hop will prevent a
router from sending Redirect messages for packets that "hit" this
static route. All this argues for using a link-local as the next-hop
address in a static route.
However, there are two cases where using a link-local address as the
next-hop clearly does not work. One is when the static route is an
indirect (or multi-hop) static route. The second is when the static
route is redistributed into another routing protocol. In these
cases, the above text from RFC 4861 notwithstanding, either a GUA or
ULA must be used.
Furthermore, many network operators are concerned about the
dependency of the default link-local address on an underlying MAC
address, as described in the previous section.
Today most operators use GUAs as next-hop addresses.
2.3. IGPs
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2.3.1. IGP Choice
One of the main decisions for an IPv6 implementer is the choice of
IGP (Interior Gateway Protocol) within the network. The primary
options are OSPF [RFC2328] [RFC5340] or IS-IS [RFC5120] [RFC5308],
though some operators may consider RIP [RFC2080] or non-standardized
protocols. Here we limit our discussion to the pros and cons of OSPF
vs. IS-IS.
The discussion in this section revolves around the options in the
table below:
+--------+--------+---------+---------+------------+----------------+
| Option | IGP | IGP for | Known | Hard | Similar |
| | for | IPv6 | to work | separation | configuration |
| | IPv4 | | well | | possible |
+--------+--------+---------+---------+------------+----------------+
| | | | | | |
+--------+--------+---------+---------+------------+----------------+
| a | IS-IS | IS-IS | YES | - | YES |
+--------+--------+---------+---------+------------+----------------+
| b | IS-IS | OSPFv3 | - | YES | - |
+--------+--------+---------+---------+------------+----------------+
| | | | | | |
+--------+--------+---------+---------+------------+----------------+
| c | OSPFv2 | IS-IS | YES | YES | - |
+--------+--------+---------+---------+------------+----------------+
| d | OSPFv2 | OSPFv3 | YES | YES | YES |
+--------+--------+---------+---------+------------+----------------+
| | | | | | |
+--------+--------+---------+---------+------------+----------------+
| e | OSPFv3 | IS-IS | - | YES | - |
+--------+--------+---------+---------+------------+----------------+
| f | OSPFv3 | OSPFv3 | - | - | YES |
+--------+--------+---------+---------+------------+----------------+
Three of the options above are marked as "Known to work well". These
options have seen significant deployments and are generally
considered to be good choices. The other options represent valid
choices, but have not seen widespread use, so it is hard to offer
comments on how well they work. In particular, options (e) and (f)
use OSPFv3 to route IPv4 [RFC5838], which is still rather new and
untested.
A number of options are marked "Hard separation". These options use
a different IGP for IPv4 vs IPv6. With these options, a problem with
routing IPv6 is unlikely to affect IPv4 or visa-versa.
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Three options are marked "Similar configuration possible". This
means it is possible (but not required) to use very similar IGP
configuration for IPv4 and IPv6: for example, the same area
boundaries, area numbering, link costing, etc. If you are happy with
your IPv4 IGP design, then this will likely be a consideration. By
contrast, the options that use IS-IS for one IP version and OSPF for
the other version will require considerably different configuration,
and will also require the operations staff to become familiar with
the difference between the two protocols.
With option (a), there is an additional choice of whether to run IS-
IS in single-topology mode (where IPv4 and IPv6 share a single
topology and a single set of link costs[RFC5308]) or multi-topology
mode (where IPv4 and IPv6 have separate topologies and potentially
different link costs[RFC5120]). A big problem with single-topology
mode is that it cannot easily accommodate devices that support
IPv4-only or IPv6-only. Thus, today there is general agreement that
multi-topology is the right choice as this gives the greatest
flexibility in network design.
It should be noted that a number of ISPs have run OSPF as their IPv4
IGP for quite a few years, but have selected IS-IS as their IPv6 IGP.
However, there are very few (none?) that have made the reverse
choice. This is, in part, because routers generally support more
nodes in an IS-IS area than in the corresponding OSPF area, and
because IS-IS is seen as more secure because it runs at layer 2.
2.4. BGP
2.4.1. Which Transport for Which Routes?
BGP these days is multi-protocol. It can carry routes from many
different families, and it can do this when the BGP session, or more
accurately the underlying TCP connection, runs over either IPv4 or
IPv6 (here referred to as either "IPv4 transport" or "IPv6
transport"). Given this flexibility, one of the biggest questions
when deploying BGP in a dual-stack network is the question of which
routes should be carried over sessions using IPv4 transport and which
should be carried over sessions using IPv6 transport.
To answer this question, consider the following table:
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+----------------+-----------+----------------------+
| Route Family | Transport | Comments |
+----------------+-----------+----------------------+
| | | |
+----------------+-----------+----------------------+
| Unlabeled IPv4 | IPv4 | Works well |
+----------------+-----------+----------------------+
| Unlabeled IPv4 | IPv6 | Next-hop issues |
+----------------+-----------+----------------------+
| Unlabeled IPv6 | IPv4 | Next-hop issues |
+----------------+-----------+----------------------+
| Unlabeled IPv6 | IPv6 | Works well |
+----------------+-----------+----------------------+
| | | |
+----------------+-----------+----------------------+
| Labeled IPv4 | IPv4 | Works well |
+----------------+-----------+----------------------+
| Labeled IPv4 | IPv6 | Next-hop issues |
+----------------+-----------+----------------------+
| Labeled IPv6 | IPv4 | (6PE) Works well |
+----------------+-----------+----------------------+
| Labeled IPv6 | IPv6 | Needs MPLS over IPv6 |
+----------------+-----------+----------------------+
| | | |
+----------------+-----------+----------------------+
| VPN IPv4 | IPv4 | Works well |
+----------------+-----------+----------------------+
| VPN IPv4 | IPv6 | Next-hop issues |
+----------------+-----------+----------------------+
| VPN IPv6 | IPv4 | (6VPE) Works well |
+----------------+-----------+----------------------+
| VPN IPv6 | IPv6 | Needs MPLS over IPv6 |
+----------------+-----------+----------------------+
The first column in this table lists various route families, where
"unlabeled" means SAFI 1, "labeled" means the routes carry an MPLS
label (SAFI 4, see [RFC3107]), and "VPN" means the routes are
normally associated with a layer-3 VPN (SAFI 128, see [RFC4364] ).
The second column lists the protocol used to transport the BGP
session, frequently specified by giving either an IPv4 or IPv6
address in the "neighbor" statement.
The third column comments on the combination in the first two
columns:
o For combinations marked "Works well", these combinations are
widely supported and are generally recommended.
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o For combinations marked "Next-hop issues", these combinations are
less-widely supported and when supported, often have next-hop
issues. That is, the next-hop address is typically a v4-mapped
IPv6 address, which is based on some IPv4 address on the sending
router. This v4-mapped IPv6 address is often not reachable by
default using IPv6 routing. One common solution to this problem
is to use routing policy to change the next-hop to a different
IPv6 address.
o For combinations marked as "Needs MPLS over IPv6", these require
MPLS over IPv6 for full support, though special policy
configuration may allow them to be used with MPLS over IPv4.
Also, it is important to note that changing the set of address
families being carried over a BGP session requires the BGP session to
be reset (unless something like [I-D.ietf-idr-dynamic-cap] or
[I-D.ietf-idr-bgp-multisession] is in use). This is generally more
of an issue with eBGP sessions than iBGP sessions: for iBGP sessions
it is common practice for a router to have two iBGP sessions, one to
each member of a route reflector pair, so one can change the set of
address families on first one of the sessions and then the other.
The following subsections discuss specific scenarios in more detail.
2.4.1.1. BGP Sessions for Unlabeled Routes
Unlabeled routes are commonly carried on eBGP sessions, as well as on
iBGP sessions in networks where Internet traffic is carried unlabeled
across the network. In these scenarios, operators today most
commonly use two BGP sessions: one session is transported over IPv4
and carries the unlabeled IPv4 routes, while the second session is
transported over IPv6 and carries the unlabeled IPv6 routes.
There are several reasons for this choice:
o It gives a clean separation between IPv4 and IPv6. This can be
especially useful when first deploying IPv6 and troubleshooting
resulting problems.
o This avoids the next-hop problem described in note 1 above.
o The status of the routes follows the status of the underlying
transport. If, for example, the IPv6 data path between the two
BGP speakers fails, then the IPv6 session between the two speakers
will fail and the IPv6 routes will be withdrawn, which will allow
the traffic to be re-routed elsewhere. By contrast, if the IPv6
routes were transported over IPv4, then the failure of the IPv6
data path might leave a working IPv4 data path, so the BGP session
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would remain up and the IPv6 routes would not be withdrawn, and
thus the IPv6 traffic would be sent into a black hole.
o It avoids resetting the BGP session when adding IPv6 to an
existing session, or when removing IPv4 from an existing session.
2.4.1.2. BGP sessions for Labeled or VPN Routes
In these scenarios, it is most common today to carry both the IPv4
and IPv6 routes over sessions transported over IPv4. This can be
done with either: (a) one session carrying both route families, or
(b) two sessions, one for each family.
Using a single session is usually appropriate for an iBGP session
going to a route reflector handling both route families. Using a
single session here usually means that the BGP session will reset
when changing the set of address families, but as noted above, this
is usually not a problem when redundant route reflectors are
involved.
In eBGP situations, two sessions are usually more appropriate.
2.4.2. eBGP Endpoints: Global or Link-Local Addresses?
When running eBGP over IPv6, there are two options for the addresses
to use at each end of the eBGP session (or more properly, the
underlying TCP session):
a. Use link-local addresses for the eBGP session, OR
b. Use global addresses for the eBGP session.
Note that the choice here is the addresses to use for the eBGP
sessions, and not whether the link itself has global (or unique-
local) addresses. In particular, it is quite possible for the eBGP
session to use link-local addresses even when the link has global
addresses.
The big attraction for option (a) is security: an eBGP session using
link-local addresses is extremely difficult to attack from a device
that is off-link. This provides very strong protection against TCP
RST and similar attacks. Though there are other ways to get an
equivalent level of security (e.g. GTSM [RFC5082], MD5 [RFC5925], or
ACLs), these other ways require additional configuration which can be
forgotten or potentially mis-configured.
However, there are a number of small disadvantages to using link-
local addresses:
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o Using link-local addresses only works for single-hop eBGP
sessions; it does not work for multi-hop sessions.
o One must use "next-hop self" at both endpoints, otherwise re-
advertising routes learned via eBGP into iBGP will not work.
(Some products enable "next-hop self" in this situation
automatically).
o Operators and their tools are used to referring to eBGP sessions
by address only, something that is not possible with link-local
addresses.
o If one is configuring parallel eBGP sessions for IPv4 and IPv6
routes, then using link-local addresses for the IPv6 session
introduces extra operational differences between the two sessions
which could otherwise be avoided.
o On some products, an eBGP session using a link-local address is
more complex to configure than a session that uses a global
address.
o If hardware or other issues cause one to move the cable to a
different local interface, then reconfiguration is required at
both ends: at the local end because the interface has changed (and
with link-local addresses, the interface must always be specified
along with the address), and at the remote end because the link-
local address has likely changed. (Contrast this with using
global addresses, where less re-configuration is required at the
local end, and no reconfiguration is required at the remote end).
o Finally, a strict application of [RFC2545] forbids running eBGP
between link-local addresses, as [RFC2545] requires the BGP next-
hop field to contain at least a global address.
For these reasons, most operators today choose to have their eBGP
sessions use global addresses.
3. General Observations
There are two themes that run though many of the design choices in
this document. This section presents some general discussion on
these two themes.
3.1. Use of Link-Local Addresses
The proper use of link-local addresses is a common theme in the IPv6
network design choices. Link-layer addresses are, of course, always
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present in an IPv6 network, but current network design practice
mostly ignores them, despite efforts such as [RFC7404].
There are three main reasons for this current practice:
o Network operators are concerned about the volatility of link-local
addresses based on MAC addresses, despite the fact that this
concern can be overcome by manually-configuring link-local
addresses;
o It is very difficult to impossible to ping a link-local address
from a device that is not on the same subnet. This is a
troubleshooting disadvantage, though it can also be viewed as a
security advantage.
o Most operators are currently running networks that carry both IPv4
and IPv6 traffic, and wish to harmonize their IPv4 and IPv6 design
and operational practices where possible.
3.2. Separation of IPv4 and IPv6
Currently, most operators are running or planning to run networks
that carry both IPv4 and IPv6 traffic. Hence the question: To what
degree should IPv4 and IPv6 be kept separate? As can be seen above,
this breaks into two sub-questions: To what degree should IPv4 and
IPv6 traffic be kept separate, and to what degree should IPv4 and
IPv6 routing information be kept separate?
The general consensus around the first question is that IPv4 and IPv6
traffic should generally be mixed together. This recommendation is
driven by the operational simplicity of mixing the traffic, plus the
general observation that the service being offered to the end user is
Internet connectivity and most users do not know or care about the
differences between IPv4 and IPv6. Thus it is very desirable to mix
IPv4 and IPv6 on the same link to the end user. On other links,
separation is possible but more operationally complex, though it does
occasionally allow the operator to work around limitations on network
devices. The situation here is roughly comparable to IP and MPLS
traffic: many networks mix the two traffic types on the same links
without issues.
By contrast, there is more of an argument for carrying IPv6 routing
information over IPv6 transport, while leaving IPv4 routing
information on IPv4 transport. By doing this, one gets fate-sharing
between the control and data plane for each IP protocol version: if
the data plane fails for some reason, then often the control plane
will too.
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4. IANA Considerations
This document makes no requests of IANA.
5. Security Considerations
This document introduces no new security considerations that are not
already documented elsewhere.
The following is a brief list of pointers to documents related to the
topics covered above that the reader may wish to review for security
considerations.
For general IPv6 security, [RFC4942] provides guidance on security
considerations around IPv6 transition and coexistence.
For OSPFv3, the base protocol specification [RFC5340] has a short
security considerations section which notes that the fundamental
mechanism for protecting OSPFv3 from attacks is the mechanism
described in [RFC4552].
For IS-IS, [RFC5308] notes that ISIS for IPv6 raises no new security
considerations over ISIS for IPv4 over those documented in [ISO10589]
and [RFC5304].
For BGP, [RFC2545] notes that BGP for IPv6 raises no new security
considerations over those present in BGP for IPv4. However, there
has been much discussion of BGP security recently, and the interested
reader is referred to the documents of the IETF's SIDR working group.
6. Acknowledgements
Many, many people in the V6OPS working group provided comments and
suggestions that made their way into this document. A partial list
includes: Rajiv Asati, Fred Baker, Michael Behringer, Marc Blanchet,
Ron Bonica, Randy Bush, Cameron Byrne, Brian Carpenter, KK
Chittimaneni, Tim Chown, Lorenzo Colitti, Gert Doering, Francis
Dupont, Bill Fenner, Kedar K Gaonkar, Chris Grundemann, Steinar Haug,
Ray Hunter, Joel Jaeggli, Victor Kuarsingh, Jen Linkova, Ivan
Pepelnjak, Alexandru Petrescu, Rob Shakir, Mark Smith, Jean-Francois
Tremblay, Dave Thaler, Tina Tsou, Eric Vyncke, Dan York, and
Xuxiaohu.
The authors would also like to thank Pradeep Jain and Alastair
Johnson for helpful comments on a very preliminary version of this
document.
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7. Informative References
[I-D.ietf-idr-bgp-multisession]
Scudder, J., Appanna, C., and I. Varlashkin, "Multisession
BGP", draft-ietf-idr-bgp-multisession-07 (work in
progress), September 2012.
[I-D.ietf-idr-dynamic-cap]
Ramachandra, S. and E. Chen, "Dynamic Capability for BGP-
4", draft-ietf-idr-dynamic-cap-14 (work in progress),
December 2011.
[I-D.ietf-v6ops-ula-usage-recommendations]
Liu, B. and S. Jiang, "Considerations For Using Unique
Local Addresses", draft-ietf-v6ops-ula-usage-
recommendations-04 (work in progress), October 2014.
[ISO10589]
International Standards Organization, "Intermediate system
to Intermediate system intra-domain routeing information
exchange protocol for use in conjunction with the protocol
for providing the connectionless-mode Network Service (ISO
8473)", International Standard 10589:2002, Nov 2002.
[RFC2080] Malkin, G. and R. Minnear, "RIPng for IPv6", RFC 2080,
January 1997.
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.
[RFC2545] Marques, P. and F. Dupont, "Use of BGP-4 Multiprotocol
Extensions for IPv6 Inter-Domain Routing", RFC 2545, March
1999.
[RFC3107] Rekhter, Y. and E. Rosen, "Carrying Label Information in
BGP-4", RFC 3107, May 2001.
[RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
Networks (VPNs)", RFC 4364, February 2006.
[RFC4472] Durand, A., Ihren, J., and P. Savola, "Operational
Considerations and Issues with IPv6 DNS", RFC 4472, April
2006.
[RFC4552] Gupta, M. and N. Melam, "Authentication/Confidentiality
for OSPFv3", RFC 4552, June 2006.
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[RFC4852] Bound, J., Pouffary, Y., Klynsma, S., Chown, T., and D.
Green, "IPv6 Enterprise Network Analysis - IP Layer 3
Focus", RFC 4852, April 2007.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
September 2007.
[RFC4942] Davies, E., Krishnan, S., and P. Savola, "IPv6 Transition/
Co-existence Security Considerations", RFC 4942, September
2007.
[RFC5082] Gill, V., Heasley, J., Meyer, D., Savola, P., and C.
Pignataro, "The Generalized TTL Security Mechanism
(GTSM)", RFC 5082, October 2007.
[RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi
Topology (MT) Routing in Intermediate System to
Intermediate Systems (IS-ISs)", RFC 5120, February 2008.
[RFC5304] Li, T. and R. Atkinson, "IS-IS Cryptographic
Authentication", RFC 5304, October 2008.
[RFC5308] Hopps, C., "Routing IPv6 with IS-IS", RFC 5308, October
2008.
[RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF
for IPv6", RFC 5340, July 2008.
[RFC5375] Van de Velde, G., Popoviciu, C., Chown, T., Bonness, O.,
and C. Hahn, "IPv6 Unicast Address Assignment
Considerations", RFC 5375, December 2008.
[RFC5838] Lindem, A., Mirtorabi, S., Roy, A., Barnes, M., and R.
Aggarwal, "Support of Address Families in OSPFv3", RFC
5838, April 2010.
[RFC5925] Touch, J., Mankin, A., and R. Bonica, "The TCP
Authentication Option", RFC 5925, June 2010.
[RFC5963] Gagliano, R., "IPv6 Deployment in Internet Exchange Points
(IXPs)", RFC 5963, August 2010.
[RFC6180] Arkko, J. and F. Baker, "Guidelines for Using IPv6
Transition Mechanisms during IPv6 Deployment", RFC 6180,
May 2011.
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[RFC6342] Koodli, R., "Mobile Networks Considerations for IPv6
Deployment", RFC 6342, August 2011.
[RFC6782] Kuarsingh, V. and L. Howard, "Wireline Incremental IPv6",
RFC 6782, November 2012.
[RFC6883] Carpenter, B. and S. Jiang, "IPv6 Guidance for Internet
Content Providers and Application Service Providers", RFC
6883, March 2013.
[RFC7217] Gont, F., "A Method for Generating Semantically Opaque
Interface Identifiers with IPv6 Stateless Address
Autoconfiguration (SLAAC)", RFC 7217, April 2014.
[RFC7381] Chittimaneni, K., Chown, T., Howard, L., Kuarsingh, V.,
Pouffary, Y., and E. Vyncke, "Enterprise IPv6 Deployment
Guidelines", RFC 7381, October 2014.
[RFC7404] Behringer, M. and E. Vyncke, "Using Only Link-Local
Addressing inside an IPv6 Network", RFC 7404, November
2014.
[v6-addressing-plan]
SurfNet, "Preparing an IPv6 Address Plan", 2013,
<http://www.ripe.net/lir-services/training/material/
IPv6-for-LIRs-Training-Course/
Preparing-an-IPv6-Addressing-Plan.pdf>.
Authors' Addresses
Philip Matthews
Alcatel-Lucent
600 March Road
Ottawa, Ontario K2K 2E6
Canada
Phone: +1 613-784-3139
Email: philip_matthews@magma.ca
Victor Kuarsingh
Dyn
150 Dow Street
Manchester, NH 03101
USA
Email: victor@jvknet.com
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