One document matched: draft-chown-homenet-arch-00.txt
Network Working Group J. Arkko
Internet-Draft Ericsson
Intended status: Informational T. Chown
Expires: March 24, 2012 University of Southampton
J. Weil
Time Warner Cable
O. Troan
Cisco Systems, Inc.
September 21, 2011
Home Networking Architecture for IPv6
draft-chown-homenet-arch-00
Abstract
This text describes the evolving networking technology within small
"residential home" networks. The goal of this memo is to define the
architecture for IPv6-based home networking. The text highlights the
impact of IPv6 on home networking, and illustrates some topology
scenarios. The architecture shows how standard IPv6 mechanisms and
addressing can be employed in home networking, lists a number of
principles that should apply, and outlines the need for specific
protocol extensions for certain additional functionality.
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
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Internet-Drafts are draft documents valid for a maximum of six months
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on March 24, 2012.
Copyright Notice
Copyright (c) 2011 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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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Effects of IPv6 on Home Networking . . . . . . . . . . . . . . 3
3. Architecture . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.1. Network Models . . . . . . . . . . . . . . . . . . . . . . 7
3.2. Requirements . . . . . . . . . . . . . . . . . . . . . . . 11
3.3. Considerations . . . . . . . . . . . . . . . . . . . . . . 12
3.4. Principles . . . . . . . . . . . . . . . . . . . . . . . . 13
3.5. Implementing the Architecture on IPv6 . . . . . . . . . . 17
4. References . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.1. Normative References . . . . . . . . . . . . . . . . . . . 18
4.2. Informative References . . . . . . . . . . . . . . . . . . 18
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 19
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1. Introduction
This memo focuses on the evolving networking technology within small
"residential home" networks and the associated challenges. For
example, a trend in home networking is the proliferation of
networking technology in an increasingly broad range of devices and
media. This evolution in scale and diversity sets requirements on
IETF protocols. Some of these requirements relate to the need for
multiple subnets for private and guest networks, the introduction of
IPv6, and the introduction of specialized networks for home
automation and sensors.
While advanced home networks have been built, most operate based on
IPv4, employ solutions that we would like to avoid such as network
address translation (NAT), or require expert assistance to set up.
The architectural constructs in this document are focused on the
problems to be solved when introducing IPv6 with a eye towards a
better result than what we have today with IPv4, as well as a better
result than if the IETF had not given this specific guidance.
This architecture document aims to provide the basis for how standard
IPv6 mechanisms and addressing [RFC2460] [RFC4291] can be employed in
home networking, while coexisting with existing IPv4 mechanisms.
Some general principles for the architecture are listed. At this
stage it is vital that introducing IPv6 does not adversely affect
IPv4 operation. Future deployments, or potentially specific subnets
within an otherwise dual-stack home network, may be IPv6-only.
Currently some parts of this text are somewhat "chatty", which is
intended to solicit feedback on the issues presented.
2. Effects of IPv6 on Home Networking
Service providers are deploying IPv6, content is becoming available
on IPv6, and support for IPv6 is increasingly available in devices
and software used in the home. While IPv6 resembles IPv4 in many
ways, it changes address allocation principles, makes multi-
addressing the norm, and allows direct IP addressability and routing
to devices in the home from the Internet. The following is an
overview of some of the key areas impacted by the implementation of
IPv6 into the home network that are both promising and problematic:
Multiple segments
While less complex layer 3 topologies involving as few subnets as
possible are preferred in home networks for a variety of reasons
including simpler management and service discovery, incorporation
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of dedicated segments remains necessary for some cases.
For instance, a common feature in modern home routers is the
ability to support both guest and private network segments. Also,
link layer networking technology is poised to become more
heterogeneous, as networks begin to employ both traditional
Ethernet technology and link layers designed for low-powered
sensor networks. Similar needs for segmentation may occur in
other cases, such as separating building control or corporate
extensions from the Internet access network. Also, different
segments may be associated with subnets that have different
routing and security policies.
Documents that provide some more specific background and depth on
this topic include: [I-D.herbst-v6ops-cpeenhancements],
[I-D.baker-fun-multi-router], and [I-D.baker-fun-routing-class].
In addition to routing, rather than NATing, between subnets, there
are issues of when and how to extend mechanisms such as service
discovery which currently rely on link-local addressing to limit
scope.
The presence of a multiple segment, multi-router network implies
that there is some kind of automatic routing mechanism in place.
In advanced configurations similar to those used in multihomed
corporate networks, there may also be a need to discover border
router(s) by an appropriate mechanism.
Multi-Addressing of devices
In an IPv6 network, devices may acquire multiple addresses,
typically at least a link-local address and a globally unique
address. Thus it should be considered the norm for devices on
IPv6 home networks to be multi-addressed, and to also have an IPv4
address where the network is dual-stack. Default address
selection mechanisms [I-D.ietf-6man-rfc3484-revise] allow a node
to select appropriate src/dst address pairs for communications,
though such selection may face problems in the event of
multihoming, where nodes may have multiple globally unique
addresses and multiple exit routers associated with them.
Unique Local Addresses (ULAs)
[RFC4193] defines Unique Local Addresses (ULAs) for IPv6 that may
be used to address devices within the scope of a single site.
Support for ULAs for CPEs is described in [RFC6204].
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A home network running IPv6 may deploy ULAs for communication
between devices within the network. Address selection mechanisms
should ensure a ULA source address is used to communicate with ULA
destination address. The use of ULAs does not imply IPv6 NAT,
rather that external communications should use a node's global
IPv6 source address.
Security, Borders, and the elimination of NAT
The end-to-end communication that is promised with IPv6 is both an
incredible opportunity for innovation and simpler network
operation, but it is also a concern as it exposes nodes in the
internal networks to receipt of otherwise unwanted traffic from
the Internet. Firewalls that restrict incoming connections may be
used to prevent exposure, however, this reduces the efficacy of
end-to-end connectivity that IPv6 has the potential to restore.
[RFC6092] provides recommendations for an IPv6 firewall that
applies "limitations on end-to-end transparency where security
considerations are deemed important to promote local and Internet
security." The firewall operation is "simple" in that there is an
assumption that traffic which is to be blocked by default is
defined in the RFC and not expected to be updated by the user or
otherwise. The RFC also discusses an option for CPEs to have an
option to be put into a "transparent mode" of operation.
It is important to distinguish between addressability and
reachability; i.e. IPv6 through use of globally unique addressing
in the home makes all devices potentially reachable from anywhere.
Whether they are or not should depend on firewall or filtering
behaviour, and not the presence or use of NAT.
Advanced Security for IPv6 CPE [I-D.vyncke-advanced-ipv6-security]
takes the approach that in order to provide the greatest end-to-
end transparency as well as security, security polices must be
updated by a trusted party which can provide intrusion signatures
an other "active" information on security threats. This is much
like a virus-scanning tool which must receive updates in order to
detect and/or neutralize the latest attacks as they arrive. As
the name implies "advanced" security requires significantly more
resources and infrastructure (including a source for attack
signatures) vs. "simple" security.
In addition to the security mechanisms themselves, it is important
to know where to enable them. If there is some indication as to
which router is connected to the "outside" of the home network,
this is feasible. Otherwise, it can be difficult to know which
security policies to apply where. Further, security policies may
be different for various address ranges if ULA addressing is setup
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to only operate within the homenet itself and not be routed to the
Internet at large. Finally, such policies must be able to be
applied by typical home users, e.g. to give a visitor in a 'guest'
network access to media services in the home.
It may be useful to classify the border of the home network as a
unique logical interface separating the home network from service
provider network/s. This border interface may be a single
physical interface to a single service provider, multiple layer 2
sub-interfaces to a single service provider, or multiple
connections to a single or multiple providers. This border is
useful for describing edge operations and interface requirements
across multiple functional areas including security, routing,
service discovery, and router discovery.
Naming, and manual configuration of IP addresses
In IPv4, a single subnet NATed home network environment is
currently the norm. As a result, it is common practice to reach a
router for configuration, DNS resolver functions, or otherwise via
192.168.1.1 or some other commonly used RFC 1918 address. In
IPv6, while ULAs exist and could potentially be used to address
internally-reachable services, little deployment experience exists
to date. In addition, generally IPv6 addresses are more
cumbersome for humans to manually configure, with a true ULA
prefix effectively being a random 48-bit prefix. As such, even
for the simplest of functions, naming and the associated discovery
of services is imperative for an easy to administer homenet.
Naming and service discovery are thus important, but they may also
be expected to operate across the scope of the entire home
network, despite crossing subnet boundaries. It should be noted
that in IPv4, these services do not generally function across home
router NAT boundaries, so this would be one area where there is
room for an improvement in IPv6.
3. Architecture
An architecture outlines how to construct home networks involving
multiple routers and subnets. In the next section this text presents
a few typical home network topology models/scenarios, followed by a
list of topics that may influence the architecture discussions. This
is followed by a set of architectural principles that govern how the
various nodes should work together. Finally, some guidelines are
given for realizing the architecture with the IPv6 addressing
architecture, prefix delegation, global and ULA addresses, source
address selection rules and other existing components of the IPv6
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architecture. The architecture also drives what protocols extensions
are necessary, as will be discussed in Section 3.5.
3.1. Network Models
Figure 1 shows the simplest possible home network topology, involving
just one router, a local area network, and a set of hosts. Setting
up such networks is in principle well understood today [RFC6204].
+-------+-------+ \
| Service | \
| Provider | | Service
| Router | | Provider
+-------+-------+ | network
| /
| Customer /
| Internet connection /
|
+------+--------+ \
| IPv6 | \
| Customer Edge | \
| Router | /
+------+--------+ /
| | End-User
Local Network | | network(s)
---+-----+-------+--- \
| | \
+----+-----+ +-----+----+ \
|IPv6 Host | |IPv6 Host | /
| | | | /
+----------+ +-----+----+ /
Figure 1
Figure 2 shows another network that now introduces multiple local
area networks. These may be needed for reasons relating to different
link layer technology or for policy reasons. Note that a common
arrangement is to have different link types supported on the same
router, bridged together. For the purposes of this memo and IP layer
operation this arrangement is considered equivalent to the topology
in Figure 1.
This topology is also relatively well understood today [RFC6204],
though it certainly presents additional demands with regards suitable
firewall policies and limits the operation of certain applications
and discovery mechanisms (which may typically today only succeed
within a single subnet).
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+-------+-------+ \
| Service | \
| Provider | | Service
| Router | | Provider
+------+--------+ | network
| /
| Customer /
| Internet connection /
|
+------+--------+ \
| IPv6 | \
| Customer Edge | \
| Router | /
+----+-------+--+ /
Network A | | Network B | End-User
---+-------------+----+- --+--+-------------+--- | network(s)
| | | | \
+----+-----+ +-----+----+ +----+-----+ +-----+----+ \
|IPv6 Host | |IPv6 Host | | IPv6 Host| |IPv6 Host | /
| | | | | | | | /
+----------+ +-----+----+ +----------+ +----------+ /
Figure 2
Figure 3 shows a little bit more complex network with two routers and
eight devices connected to one ISP. This network is similar to the
one discussed in [I-D.ietf-v6ops-ipv6-cpe-router-bis]. The main
complication in this topology compared to the ones described earlier
is that there is no longer a single router that a priori understands
the entire topology. The topology itself may also be complex. It
may not be possible to assume a pure tree form, for instance. This
would be a consideration if there was an assumption that home users
may plug routers together to form arbitrary topologies.
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+-------+-------+ \
| Service | \
| Provider | | Service
| Router | | Provider
+-------+-------+ | network
| /
| Customer /
| Internet connection
|
+------+--------+ \
| IPv6 | \
| Customer Edge | \
| Router | |
+----+-+---+----+ |
Network A | | | Network B/E |
----+-------------+----+ | +---+-------------+------+ |
| | | | | | | |
+----+-----+ +-----+----+ | +----+-----+ +-----+----+ | |
|IPv6 Host | |IPv6 Host | | | IPv6 Host| |IPv6 Host | | |
| | | | | | | | | | |
+----------+ +-----+----+ | +----------+ +----------+ | |
| | | | |
| ---+------+------+-----+ |
| | Network B/E |
+------+--------+ | | End-User
| IPv6 | | | networks
| Interior +------+ |
| Router | |
+---+-------+-+-+ |
Network C | | Network D |
----+-------------+---+- --+---+-------------+--- |
| | | | |
+----+-----+ +-----+----+ +----+-----+ +-----+----+ |
|IPv6 Host | |IPv6 Host | | IPv6 Host| |IPv6 Host | |
| | | | | | | | /
+----------+ +-----+----+ +----------+ +----------+ /
Figure 3
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+-------+-------+ +-------+-------+ \
| Service | | Service | \
| Provider A | | Provider B | | Service
| Router | | Router | | Provider
+------+--------+ +-------+-------+ | network
| | /
| Customer | /
| Internet connections | /
| |
+------+--------+ +-------+-------+ \
| IPv6 | | IPv6 | \
| Customer Edge | | Customer Edge | \
| Router 1 | | Router 2 | /
+------+--------+ +-------+-------+ /
| | /
| | | End-User
---+---------+---+---------------+--+----------+--- | network(s)
| | | | \
+----+-----+ +-----+----+ +----+-----+ +-----+----+ \
|IPv6 Host | |IPv6 Host | | IPv6 Host| |IPv6 Host | /
| | | | | | | | /
+----------+ +-----+----+ +----------+ +----------+
Figure 4
Figure 4 illustrates a multihomed home network model, where the
customer has connectivity via CPE1 to ISP A and via CPE2 to ISP B.
This example shows one shared subnet where IPv6 nodes would
potentially be multihomed and received multiple IPv6 global
addresses, one per ISP. This model may also be combined with that
shown in Figure 3 for example to create a more complex scenario.
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+-------+-------+ +-------+-------+ \
| Service | | Service | \
| Provider A | | Provider B | | Service
| Router | | Router | | Provider
+-------+-------+ +-------+-------+ | network
| | /
| Customer | /
| Internet | /
| connections | |
+---------+---------+ \
| IPv6 | \
| Customer Edge | \
| Router 1 | /
+---------+---------+ /
| | /
| | | End-User
---+---------+---+-- --+--+----------+--- | network(s)
| | | | \
+----+-----+ +-----+----+ +----+-----+ +-----+----+ \
|IPv6 Host | |IPv6 Host | | IPv6 Host| |IPv6 Host | /
| | | | | | | | /
+----------+ +-----+----+ +----------+ +----------+
Figure 5
Figure 5 illustrates a model where a home network may have multiple
connections to multiple providers or multiple logical connections to
the same provider, but the associated subnet(s) are isolated. Some
deployment scenarios may require this model.
3.2. Requirements
[RFC6204] defines "basic" requirements for IPv6 Customer Edge
Routers, while [I-D.ietf-v6ops-ipv6-cpe-router-bis] describes
"advanced" features. In general, home network equipment needs to
cope with the different types of network topologies discussed above.
Manual configuration is rarely, if at all, possible, given the
knowledge lying with typical home users. The equipment needs to be
prepared to handle at least
o Prefix configuration for routers
o Managing routing
o Name resolution
o Service discovery
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o Network security
3.3. Considerations
This section lists some considerations for home networking that may
affect the architecture depending on how or if they are included.
Comments are certainly required here.
Multihoming
A home network may be multihomed to multiple providers. This may
either take a form where there are multiple isolated networks
within the home or a more integrated network where the
connectivity selection is dynamic. Current practice is typically
of the former kind.
In an integrated network, specific appliances or applications may
use their own external connectivity, or the entire network may
change its connectivity based on the status of the different
upstream connections. Many general solutions for IPv6 multihoming
have been worked for years in the IETF and to date there is little
deployment of these mechanisms. An argument can be made that home
networking standards should not make another attempt at this. An
obvious counter-argument is that multihoming support may be
necessary for many deployment situations.
In any case, if multihoming is supported, additional requirements
are necessary as described in [I-D.baker-fun-multi-router]. In
the case of multiple exit routers, either the use of NAT66
[RFC6296] or an alternative approach may be needed, e.g.
[I-D.v6ops-multihoming-without-ipv6nat]. One could also argue
that a "happy eyeballs" viewpoint, not too dissimilar to that
proposed for multiple interface (mif) scenarios is also
acceptable. The central part of the arguments about IPv6
multihoming is whether all devices exist in the same multihomed
network, and if they, do they have one or multiple IPv6 addresses.
Quality of Service in multi-service home networks
Support for QoS between multiple services may be a requirement,
e.g. for a critical system (perhaps healthcare related), or for
differentiation between different types of traffic (file sharing,
cloud storage, live streaming, VoIP, etc). Different media types
may have different QoS properties or capabilities.
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A counter-argument for adding any specific support for home
networking related standards is that again, there is little
practical deployment of QoS mechanism even in the general
networking world, let alone home networks. It could also be
argued that simpler mechanisms are more cost-effective, such as
ensuring proper buffering algorithms to avoid the bufferbloat
problem as described in [Gettys11].
DNS services
Consideration will need to be given for existing protocols that
may be used within a network, e.g. mDNS. With the introduction of
new top level domains, there is potential for ambiguity between
for example a local host called apple and (if it is registered) an
apple gTLD, so some local name space is probably required, and one
that may be configurable by a home user. It is probably desirable
to have DNS treated the same within a home network for IPv4 and
IPv6. This will fall under the naming and service discovery
requirements. More input needed here.
Privacy considerations
There has been some suggestion to include privacy consideration in
homenet. What do we want to say about that here?
3.4. Principles
There is little that the Internet standards community can do about
the physical topologies or the need for some networks to be separated
at the network layer for policy or link layer compatibility reasons.
However, there is a lot of flexibility in using IP addressing and
inter-networking mechanisms. It would be desirable to provide some
guidance on how this flexibility should be used to provide the best
user experience and ensure that the network can evolve with new
applications in the future.
The authors believe that the following principles guide us in
designing these networks in the correct manner. There is no implied
priority by the order in which the principles are listed.
Reuse existing protocols
It is desirable to reuse existing protocols where possible, but at
the same time to avoid consciously precluding the introduction of
new or emerging protocols. For example,
[I-D.baker-fun-routing-class] suggests introducing a routing
protocol that may may route on both source and destination
addresses. Protocols used should be backwardly compatible.
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Do we wish to say anything about other home networking related
standards or groups, e.g. DLNA?
Dual-stack Operation
Any solutions for IPv6 must not adversely affect IPv4 operation.
While RFC 6204 is targeted at IPv6-only networks, it is likely
that dual-stack home networks will be the norm for some period of
time, but IPv6-only home networks will be deployed in due course,
perhaps first in "greenfield" scenarios, or may appear as one
element of an otherwise dual-stack network. It is likely that
topologies of IPv4 and IPv6 networks would be as congruent as
possible.
Should the text say anything to say about transition tool use?
Some discussion has also happened on mapping of external IPv6
addresses to internal IPv4 ones.
Largest Possible Subnets
Today's IPv4 home networks generally have a single subnet, and
early dual-stack deployments have a single congruent IPv6 subnet,
possibly with some bridging functionality. Future home networks
are highly likely to need multiple subnets, for reasons described
earlier. As part of the self-organization of the network, the
network should subdivide itself to the largest possible subnets
that can be constructed with the constraints of link layer
mechanisms, bridging, physical connectivity, and policy. For
instance, separate subnetworks are necessary where two different
links cannot be bridged, or when a policy requires the separation
of a private and visitor parts of the network.
While it may be desirable to maximise the chance of link-local
protocols succeeding, multiple subnet home networks are
inevitable, so their support must be included. A general
recommendation is to follow the same topology for IPv6 as is used
for IPv4, but not to use NAT. Thus there should be routed IPv6
where an IPv4 NAT is used, and where there is no NAT there should
be bridging.
** Perhaps add a Figure here to illustrate the principle.
Transparent End-to-End Communications
An IPv6-based home network architecture should naturally offer a
transparent end-to-end communications model. Each device should
be addressable by a unique address. Security perimeters can of
course restrict the end-to-end communications, but it is much
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easier to block certain nodes from communicating than it is to re-
enable nodes to communicate if they have been hidden behind
address translation devices.
As discussed previously, it is important to note the difference
between addressable and reachable. So filtering is to be
expected, but NAT is not. For configuring filters, protocols for
securely associating devices would be desirable. The use of
protocols including uPnP or PCP may be expected. A default
'transparent mode' (as per RFC6092) may be used.
Local addressing (ULAs) may be used within the scope of a home
network. Should ULAs be encouraged for all devices or only those
intended to have internal connectivity only? IPv4 "thinking"
would incorrectly associate ULAs with use of NAT.
IP Connectivity between All Nodes
A logical consequence of the end-to-end communications model is
that the network should attempt to provide IP-layer connectivity
between all internal parts as well as between the internal parts
and the Internet. This connectivity should be established at the
link layer, if possible, and using routing at the IP layer
otherwise.
Some home networking scenarios/models may involve isolated
subnet(s) with their own CPEs. In such cases connectivity would
only be expected within each isolated network (though traffic may
potentially pass between them via external providers).
Routing functionality
Routing functionality is required when multiple subnets are in
use. This functionality could be as simple as the current
"default route is up" model of IPv4 NAT, or it could be running an
actual routing protocol.
The requirements for solutions in this area are unclear, but it
seems likely that a solution is required and that it should be
something that can work across different types of devices in the
same home network.
If an actual routing protocol is needed, is it necessary to pick
one? If there are multiple protocols, will some kind of
negotation be needed?
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If one routing protocol is recommended, which one should it be?
Should the selection of the solution be guided by what already
exists in most devices (the running code approach) or what
satisfies the full requirements (the design principle)?
Should sensor and machine-to-machine communication networks be
dealt with as separate networks, or as a part of the routing
mechanisms that handle the entire home network? Or are the
requirements and mechamisms for home networks too different from
these specialized, low-power networks that attempting to use one
solution would merely cause harm? Current home deployments use
largely different mechanisms in sensor and basic Internet
connectivity networks.
Self-Organization
A home network architecture should be naturally self-organizing
and self-configuring under different circumstances relating to
connectivity status to the Internet, number of devices, and
physical topology.
Least Topology Assumptions
There should be ideally no built-in assumptions about the topology
in home networks, as users are capable of connecting their devices
in ingenious ways. Thus arbitrary topologies will need to be
supported.
Discovery
The most natural way to think about naming and service discovery
within a home is to enable it to work across the entire residence,
disregarding technical borders such as subnets but respecting
policy borders such as those between visitor and internal
networks.
This implies support for IPv6 multicast across the scope of the
home network, and thus at least all routing devices in the
network.
Proxy or Extend?
Related to the above, it would be desirable to decide whether in
general existing protocols that are designed to only work within a
subnet are modified/extended to work across subnets, or whether
proxy capabilities are defined for those functions.
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We may need to do more analysis (a survey?) on which functions/
protocols assume subnet-only operation, in the context of existing
home networks (which today are most commonly a single subnet).
Some experience from enterprises may be relevant here.
Adapt to ISP constraints
The home network may receive an arbitrary length IPv6 prefix from
its provider, e.g. /60 or /56. The offered prefix may be static
or dynamic. The home network needs to be adaptable to such ISP
policies, e.g. on constraints placed by the size of prefix offered
by the ISP. The ISP may use [I-D.ietf-dhc-pd-exclude] for
example.
The internal operation of the home network should not also depend
on the availability of the ISP network at any given time, other
than for connectivity to services or systems off the home network.
Intelligent Policy
As the Internet continues to evolve, no part of the architecture
or security design should depend on hard coding acceptable or
unacceptable traffic patterns into the devices. Rather, these
traffic patterns should be driven off up-to-date databases in the
Internet.
This principle should also cover consideration to avoid hard
coding IP literals or taking other actions that unnecessarily
complicate any required home network renumbering operation.
3.5. Implementing the Architecture on IPv6
The necessary mechanisms are largely already part of the IPv6
protocol set and common implementations. The few known counter-
examples are discussed in the following section. For automatic
routing, it is expected that existing routing protocols can be used
as is. However, a new mechanism may be needed in order to turn a
selected protocol on by default. Support for multiple exit routers
and multi-homing would also require extensions. For name resolution
and service discovery, extensions to existing multicast-based name
resolution protocols are needed to enable them to work across
subnets, within the scope of the home network.
The hardest problems in developing solutions for home networking IPv6
architectures include discovering the right borders where the domain
"home" ends and the service provider domain begins, deciding whether
some of necessary discovery mechanism extensions should affect only
the network infrastructure or also hosts, and the ability to turn on
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routing, prefix delegation and other functions in a backwards
compatible manner.
4. References
4.1. Normative References
[RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", RFC 2460, December 1998.
[RFC4193] Hinden, R. and B. Haberman, "Unique Local IPv6 Unicast
Addresses", RFC 4193, October 2005.
[RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing
Architecture", RFC 4291, February 2006.
[RFC6092] Woodyatt, J., "Recommended Simple Security Capabilities in
Customer Premises Equipment (CPE) for Providing
Residential IPv6 Internet Service", RFC 6092,
January 2011.
[RFC6204] Singh, H., Beebee, W., Donley, C., Stark, B., and O.
Troan, "Basic Requirements for IPv6 Customer Edge
Routers", RFC 6204, April 2011.
[RFC6296] Wasserman, M. and F. Baker, "IPv6-to-IPv6 Network Prefix
Translation", RFC 6296, June 2011.
4.2. Informative References
[I-D.baker-fun-multi-router]
Baker, F., "Exploring the multi-router SOHO network",
draft-baker-fun-multi-router-00 (work in progress),
July 2011.
[I-D.baker-fun-routing-class]
Baker, F., "Routing a Traffic Class",
draft-baker-fun-routing-class-00 (work in progress),
July 2011.
[I-D.herbst-v6ops-cpeenhancements]
Herbst, T. and D. Sturek, "CPE Considerations in IPv6
Deployments", draft-herbst-v6ops-cpeenhancements-00 (work
in progress), October 2010.
[I-D.vyncke-advanced-ipv6-security]
Vyncke, E., Yourtchenko, A., and M. Townsley, "Advanced
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Security for IPv6 CPE",
draft-vyncke-advanced-ipv6-security-02 (work in progress),
July 2011.
[I-D.ietf-v6ops-ipv6-cpe-router-bis]
Singh, H., Beebee, W., Donley, C., Stark, B., and O.
Troan, "Advanced Requirements for IPv6 Customer Edge
Routers", draft-ietf-v6ops-ipv6-cpe-router-bis-01 (work in
progress), July 2011.
[I-D.ietf-6man-rfc3484-revise]
Matsumoto, A., Kato, J., Fujisaki, T., and T. Chown,
"Update to RFC 3484 Default Address Selection for IPv6",
draft-ietf-6man-rfc3484-revise-04 (work in progress),
July 2011.
[I-D.ietf-dhc-pd-exclude]
Korhonen, J., Savolainen, T., Krishnan, S., and O. Troan,
"Prefix Exclude Option for DHCPv6-based Prefix
Delegation", draft-ietf-dhc-pd-exclude-03 (work in
progress), August 2011.
[I-D.v6ops-multihoming-without-ipv6nat]
Troan, O., Miles, D., Matsushima, S., Okimoto, T., and D.
Wing, "IPv6 Multihoming without Network Address
Translation", draft-v6ops-multihoming-without-ipv6nat-00
(work in progress), March 2011.
[Gettys11]
Gettys, J., "Bufferbloat: Dark Buffers in the Internet",
March 2011,
<http://www.ietf.org/proceedings/80/slides/tsvarea-1.pdf>.
Appendix A. Acknowledgments
The authors would like to thank to Stuart Cheshire, James Woodyatt,
Lars Eggert, Ray Bellis, David Harrington, Wassim Haddad, Heather
Kirksey, Dave Thaler, Fred Baker, and Ralph Droms for interesting
discussions in this problem space, and Mark Townsley for being an
initial editor/author of this text before taking his position as
homenet WG co-chair.
** Additional acknowledgements TBA.
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Authors' Addresses
Jari Arkko
Ericsson
Jorvas 02420
Finland
Email: jari.arkko@piuha.net
Tim Chown
University of Southampton
Highfield
Southampton, Hampshire SO17 1BJ
United Kingdom
Email: tjc@ecs.soton.ac.uk
Jason Weil
Time Warner Cable
13820 Sunrise Valley Drive
Herndon, VA 20171
USA
Email: jason.weil@twcable.com
Ole Troan
Cisco Systems, Inc.
Drammensveien 145A
Oslo N-0212
Norway
Email: ot@cisco.com
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