Internet Engineering Task Force A.Durand
INTERNET-DRAFT SUN Microsystems,inc.
June, 24, 2004Network Working Group F. Parent
Expires December 23, 2004
Expires: April 1, 2005 A. Durand
France Telecom R&D
Goals for assisted tunneling
<draft-ietf-v6ops-assisted-tunneling-requirements-00.txt> Registered Assisted Tunneling
Status of this Memo
This document is an Internet-Draft and is in full conformance with subject to all provisions
of Section 10 section 3 of RFC 3667. By submitting this Internet-Draft, each
author represents that any applicable patent or other IPR claims of
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Copyright (C) The Internet Society (2004). All Rights Reserved.
This document defines requirements for a tunnel set-up protocol that
could be used by an ISP to jumpstart its IPv6 offering to its
customers by providing them IPv6 connectivity without having to
upgrade its access network. through tunneling.
Table of Contents
1. Goal and Scope of the Document . . . . . . . . . . . . . . . . 3
2. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Requirements for Simplicity . . . . . . . . . . . . . . . . . 5
4. Protocol Requirements . . . . . . . . . . . . . . . . . . . . 5
4.1 Address and Prefix Delegation . . . . . . . . . . . . . . 6
4.2 Registration . . . . . . . . . . . . . . . . . . . . . . . 6
4.3 Authentication . . . . . . . . . . . . . . . . . . . . . . 6
4.4 Confidentiality . . . . . . . . . . . . . . . . . . . . . 7
4.5 Service Discovery . . . . . . . . . . . . . . . . . . . . 7
4.6 NAT Traversal . . . . . . . . . . . . . . . . . . . . . . 7
4.7 Firewall Traversal . . . . . . . . . . . . . . . . . . . . 7
4.8 Accounting . . . . . . . . . . . . . . . . . . . . . . . . 8
5. General Requirements . . . . . . . . . . . . . . . . . . . . . 8
5.1 Scalability . . . . . . . . . . . . . . . . . . . . . . . 8
5.2 NAT Considerations . . . . . . . . . . . . . . . . . . . . 8
5.3 Keep-alive . . . . . . . . . . . . . . . . . . . . . . . . 9
5.4 Security . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.5 Traceability . . . . . . . . . . . . . . . . . . . . . . . 9
5.6 Phase Out . . . . . . . . . . . . . . . . . . . . . . . . 9
5.7 Extensibility . . . . . . . . . . . . . . . . . . . . . . 9
6. Compatibility with other Transition Mechanisms . . . . . . . . 10
7. Security Considerations . . . . . . . . . . . . . . . . . . . 10
8. Acknowlegements . . . . . . . . . . . . . . . . . . . . . . . 10
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 11
9.1 Normative References . . . . . . . . . . . . . . . . . . . . 11
9.2 Informative References . . . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 12
A. Changes from version 00 . . . . . . . . . . . . . . . . . . . 12
Intellectual Property and Copyright Statements . . . . . . . . 14
1. Goal and Scope of the Document
The v6ops working group has worked on requirements and scenarios for
IPv6 deployment by soliciting input from network operators. This
work has identified a need for an "assisted tunneling" mechanism.
For example, an ISP starting its IPv6 offering to its customers
without upgrading its access network to support IPv6 could use a
"tunnel brokering solution" [ISP, section 5.1.] (section 5.1
[I-D.ietf-v6ops-isp-scenarios-analysis]) a la . [RFC3053]. What has
been identified as missing from that RFC document is a tunnel set-up
In an ISP network, getting IPv6 connectivity to the customers
involves upgrading the access network to support IPv6, which can take
a long time and/or be costly. A tunneled infrastructure can be used
as a low cost migration path [ISP, section 5.1]. (section 5.1
With such an infrastructure, the ISP can connect its customers to its
IPv6 network using its production IPv6 address space, thus
facilitating migration towards native IPv6 deployment. The IPv6
deployment roadmap for connecting customers becomes:
- may become:
o assisted tunneling infrastructure to early adopters,
o native IPv6 to customers where economically justified,
o native IPv6 to all customers.
Note that, as
Contrary to automatic tunneling mechanism where the IPv4 address is
embedded inside the IPv6 address, no special format are imposed on
the IPv6 address used in assisted tunneling. Prefix delegation is
also possible. As the addressing space used during the transition to
native remains the same same, the customer routing, filtering, accounting
[ISP, section 5.]
stay the same, and there is no need to maintain any kind of relay.
"Assisted tunneling" is used in this document to described describe a
transition mechanism where the parameters to configure a bi-
bi-directional tunnel between an end-node (or leaf network) and a
router in the core of an ISP are exchanged through a tunnel set-up
protocol. Although this exchange can be automated, this remains
different from transition mechanisms like 6to4 that is fully automatic. 6to4, Teredo and
ISATAP, on the other hand, practically require receiving information
about the available prefix or address from the server/router,
comparable to the most simple form of assisted tunneling. ISATAP. In
particular, the 'registered' mode defined in section 4 assisted tunneling enables explicit access control to the
tunneled IPv6 connectivity, where the other transion mechanisms have
to rely on other kinds of control (e.g., access control based on the
IPv4 address). Also, assisted tunneling protocol negotiate the
tunnel parameters and does not depend on having the IPv4 address
inside the IPv6 address, for example.
This document analyze analyzes the requirements for such a tunnel set-up
protocol. The v6ops WG scenario and evaluation documents for
deploying IPv6 within common network environments are used as input
to this document.
Assisted tunneling is applicable in different IPv6 transition
scenarios. The focus of this document is to define the requirements
to apply this mechanism in the IPv4 ISP context making the following
o ISP is offering IPv6 connectivity to its customers initially using
controlled tunneling infrastructure [ISP,
[I-D.ietf-v6ops-isp-scenarios-analysis], section 5.1 Steps "Steps in
Transitioning Customer Connection Networks]
- The customer configuration may be diverse, and not necessarily
predictable by the ISP. Networks"
o Provider network where deployment of IPv6 is done in a more
controlled manner or when the provider cannot rely on IPv4 related
authentication (e.g. roaming customers, users not connected to
ISP access network). In such networks, ease of debugging,
traceability, filtering and so on are important features.
o The customer configuration may be diverse, and not necessarily
predictable by the ISP. The protocol must be able to adapt to the
following cases, for example by choosing the most optimal tunnel
encapsulation depending on the presence of a NAT.
* a single node,
* a leaf network,
* using a globally routable IPv4 address,
* behind a NAT (customer or ISP owned),
* using dynamic IPv4 address (internally or externally to the
There are actually two cases where the IPv4 address of the customer
tunnel end point can be dynamic, and both must be supported:
o The device used as tunnel end point is using a dynamic IPv4
address provided by the ISP.
o The device used as tunnel end point is located behind a customer
owned NAT box that is also acting as a local DHCP server. In that
case, the device IPv4 address may change after a reboot.
Althought the main focus of this document is the ISP scenario,
assisted tunneling is applicable in all the other scenarios:
unmanaged, enterprise and 3GPP.
In unmanaged networks, networks [RFC3904], assisted tunneling is applicable in
the case A
(a where a gateway which does not provide IPv6 at all) [UNMANAGED, section 3] all (section 3),
and case C (a where a dual-stack gateway is connected to an IPv4-only ISP)
[UNMANAGED, section 5].
ISP (section 5).
In 3GPP networks, the enterprise scenario [I-D.ietf-v6ops-ent-analysis], assisted
tunneling can be used in the context of
dual stack UE to support remote users connecting to IPv6 nodes through a 3GPP the
enterprise network that
only supports IPv4 PDP contexts [3GPP, 3.1]. (section 7.5.2).
3. Requirements for Simplicity
The tunnel set-up protocol must be simple to implement and easy to
deploy. In particular, it should not depend on any complex, yet to
be designed, protocols or infrastructure pieces.
This protocol is a transition mechanism, thus does not need to be
perfect. As a matter of fact, making it perfect would be counter
productive, at it would first delay its definition, then make its
deployment more cumbersome and, last but not least, diminish the
incentives to deploy native IPv6.
4. Protocol Requirements
Assisted tunneling can be provided in two different modes. "Non-
registered" mode is a simple mode with no user registration,
essentially deployed in a controlled and "authenticated" environment
where the service is made available to all the IPv4 customers.. The
"registered" mode is aimed at production deployment which requires
the user to be authenticated. authenticated (such as using a shared secret mechanism
Section 4.3). This mode can be used to offer the tunneling service to roaming
users or (users that are not directly connected to the ISP access
network), and/or restrict the service to specific (authenticated) users. The tunnel set-up protocol must
support both modes, however ISP deploying it may choose to only
support one mode of operation.
Assisted tunneling in the non-registered mode is defined for simple
"plug & play" scenarios. In this mode, the tunnel establishment is
triggered through the execution of
From a simple program, without any pre-
configuration or pre-registration user point of view, an initial registration process may be
required from the end-user.
The tunnel established is "anonymous" in a sense as the end-user does
not register explicitly to the server. An ISP before using the protocol in service. If the service provider uses an
existing authentication database (Section 4.2), this mode step may not be offering
From an ISP point of view, this makes a free service clear link between a tunnel
and doesn't wish a user (account). It provides some means to require
any form of registration. This free :
o meet requirements such as tracing (section 5.4
o control service can also be used provision to offer
trial IPv6 service limited valid and/or identified or even
selected users (section 5.2
o less prone to the ISP customers by relying on IPv4
The registered mode offers some extra features documented in latter
sections. This mode is most valuable in a provider network where
deployment denial of IPv6 service attacks: Since every tunnel
request are authenticated, it is done in a more controlled manner or when difficult to request
multiple tunnels to saturate the
provider cannot rely on IPv4 related authentication (e.g. roaming
customers). In such networks, ease of debugging, traceability,
filtering and so on are important features.
o stay in touch with users
4.1 Address and Prefix Delegation
The protocol must support delegation of an IPv6 address (/128) to prefix. The length
of the end-node IPv6 prefix delegated must be
supported in both modes.
In non-registered mode, the IPv6 address is "transient" and may
change, but configurable on the protocol SHOULD offer a mechanism to provide IPv6
address stability in this mode (e.g. cookie mechanism). server. The
implementation of this mechanism MUST allow this feature to be turned
off. In registered mode, the
protocol MUST must be able to support
servers willing to offer stable IPv6 prefixes to the
The registered mode MUST support delegation
Assignment of a single an IPv6 address or a
whole prefix. The length of (/64) to the IPv6 prefix delegated MUST end-node must be
Since no special address format is imposed, the server. The non-registered mode MAY support
See section 5.9 for DNS considerations. ISP's address space
can be used in the delegation (section 5.1
The registration of credentials is external to the protocol. A The
user may require registration prior to using this service (through
some web based service or other means). Or service provider may use
an existing authentication database to pre-register its users.
In order to allow a service provider SHOULD be able to use its existing
database. If necessary, database, an implementation may provide hooks to
facilitate integration with the ISP management infrastructure (e.g.
RADIUS for AAA, billing). billing) ([I-D.ietf-v6ops-isp-scenarios-analysis],
The protocol MAY may send information about registration procedure when a
non-registered client requests registered mode (ex: URL to provider
registration web page).
Authentication can be used to control user has access to the IPv6
services (section 5.2 [I-D.ietf-v6ops-isp-scenarios-analysis])
The authentication mechanism supported should be compatible with
standardized methods that are generally deployed. In order to assure
interoperability, at least one common authentication method MUST must be
supported. Other authentication MAY may be supported and should be
negotiated between the client and server (e.g., SASL ).
4.4. Service Discovery
In order to offer "plug & play", the implementation SHOULD allow a
mechanism to discover [RFC2222]).
Assisted tunneling can be used across networks which are not under
the service provider control (e.g., roaming users). The tunnel
set-up protocol should allow protection of the authentication data
Section 4.3. This can be achieve by selecting an authentication
mechanism that protects the credentials (e.g., digest-md5).
Protecting the tunneled data (IPv6 in this case) should be possible.
A possible usage scenario is when an enterprise's users is working
off-site and tunneling to the enterprise network (7.5.2
[I-D.ietf-v6ops-ent-analysis]). Mechanisms do exist to make this
possible, such as using IPsec over IPv6 [RFC2401].
[I-D.tschofenig-v6ops-secure-tunnels] may be applicable here but is
not analysed further.
4.5 Service Discovery
In order to facilitate deployment, the implementation should allow a
mechanism to discover the address of the server that will provide the
This discovery should be automatic when the protocol is used within
an ISP network.
4.5. There is no service discovery requirements when used
outside the provider network (roaming users, 3rd party ISP).
Tunnel end-point discovery mechanism work
([I-D.palet-v6ops-tun-auto-disc] may be applicable here.
4.6 NAT Traversal
Tunneling through IPv4 NAT MUST must be supported. The protocol should
detect if an IPv4 NAT is in the path during the set-up phase (section
5.2). If a NAT is present, an extra level of encapsulation is
necessary to tunnel IPv6 across the NAT. If no NAT is detected,
IPv6-over-IPv4 tunneling (IP protocol 41) is enough.
4.6. usually enough (see also
NAT traversal is identified as a requirement in ISP scenarios
(section 5.1 [I-D.ietf-v6ops-isp-scenarios-analysis]) and unmanaged
scanarios (section 7, Recommendation 1 [RFC3904])
4.7 Firewall Traversal
Even if no NAT is in the tunnel path, there may be a firewall which
prohibits IP protocol 41. In such case, the tunnel encapsulation
selection based on NAT detection (section 5.3) (Section 5.2) will select a tunnel
that will not work.
In some cases, when the firewall is managed by the ISP or customer,
it can be configured to allow IP protocol 41. In such cases this may
not be an issue (section 5.1 [I-D.ietf-v6ops-isp-scenarios-analysis])
But in order to be functional in any situation (e.g., firewall
lacking feature), the assisted tunneling implementation MUST must allow a
user to explicitly specify the desired tunnel encapsulation,
regardless of the NAT detection process.
The assisted tunneling should include tools for managing and
monitoring the provided service. Such information can be used to
plan service capacity (traffic load) or billing information.
Some useful accounting data are (not exhaustive list):
o Tunnel counters (traffic in/out)
o User utilization (tunnel uptime)
o System logging (authentication failures, resource exhaustion,
The interface used to provide such information can be through SNMP or
an AAA protocol (e.g., RADIUS accounting).
4.8. Security Threat Analysis
The non registered mode does not require explicit authentication of
the user. Access control may be performed using e.g., IPv4 address.
5. General Requirements
The mode essentially offer the IPv6 service to any of its IPv4
customers. Deployment of the service with this mode must be done
carefully. In particular, security considerations tunnel set-up protocol must be taken into
Non registered service scalable. Typically, this
protocol should be limited deployable in an ISP or enterprise network.
A scalability requirement which is not related to the provider network,
where access of the service can be controlled based on the IPv4
address of the users (filtering). If specific filtering is not in
place in the ISP core network, anyone on the Internet could start
using its tunneling infrastructure to get free IPv6 connectivity,
transforming effectively the ISP into a IPv6 transit provider.
If IPv4 address spoofing protocol itself
is possible within the access network, a
number of DoS attack can happen. For example, customer A can
impersonate someone else's IPv4 address during the set-up phase and
redirect a tunnel to that IP address. A then can, for example, start
a high bandwidth multimedia flow across that tunnel and saturate its
But even with filtering in place, the non registered mode is
vulnerable be able to denial of service attacks: a customer A behind a NAT
can use a large number of (private) IPv4 addresses and request deploy multiple tunnels.That would quickly saturate servers inside the ISP tunnel server
infrastructure. In order to minimize such attacks, IPv4 return
routability checks could help blocking many DoS attack. Also, network. To
do so, the server implementation should offer a way to throttle and limit the
number of tunnel established to the same (non-private) IPv4 address.
In registered mode, the protocol must make sure that the tunnel is
established to the legitimate would possibly need some load
balancing feature and authenticated destination, again to
avoid having someone establish a tunnel to a potential victim. IPv4
return routability checks could help block possible DoS attacks.
5. General Requirements
The tunnel set-up protocol must be scalable. Typically, this protocol
should be deployable in broadband ISP. an IPv6 IGP.
5.2 Service discovery requirements
The discovery part of the tunnel set-up protocol should be as
automatic as possible.
The discovery mechanism must be able to scale for large ISP who cover
different geographical areas and/or have a large number of customers.
Customers may very well try to use this tunnel set-up protocol even
if their ISP is not offering the service. In this case, without any
previous action taken by their ISP, the discovery part of the tunnel
set-up protocol must be able to abort immediately and display the
customers a message explaining that no service is available.
5.3 NAT Considerations
The assisted tunnel established by the protocol to be designed must
work with the existing infrastructure, in particular it must be
compatible with the various customer premise equipments available
today. This means that, in particular, the tunnels must be able to
traverse one or many NAT boxes of different kinds. There is no
requirement for any particular NAT traversal technology. However, as
NAT traversal usually requires an extra layer of encapsulation, the
tunnel set-up protocol SHOULD should be able to detect automatically the
presence of one or more NAT boxes in the path.
The implementation MUST implementation¬ must provide an option to to turn on extra
encapsulation manually. In order to assure interoperability, at
least one common tunnel encapsulation type MUST must be supported.
When a tunnel has to cross a NAT box, the mapping established by the
NAT must be preserved as long as the tunnel is in use. This is
usually achieved by sending keep alive messages across the tunnel.
Also, the same keep alive messages can enable the ISP tunnel end
point to perform garbage collection of its resources when tunnels are
not in use anymore. To enable those two functionalities, the tunnel
set-up protocol must include the transmission of keep-alive messages.
A client MAY may choose not to send those messages (for example on ISDN
type links), but should then expect that the tunnel may be
disconnected at any time by links). In this case, the ISP and client should be prepared able to restart the
5.5 Latency in Set-up Phases
In certain type of networks, keeping tunnels active all the time is
not possible (e.g., limited number of tunnels on server) or simply
too expensive (e.g., wireless environments where periodic
transmission is expensive). In those environments, the protocol must handle a
tunnel disconnect event and be able to set-up tunnels on demand of restart the IPv6 applications
requiring external connectivity.
The tunnel set-up protocol must then have a low enough latency phase to
enable quasi-instant configuration. Latency is usually a function of
re-establish the number of packet exchanges required, so minimizing this parameter
The tunnel set-up protocol must not introduce any new vulnerability
to the network.
5.7 See security considerations in Section 7.
In some production environment, traceability is an important
consideration ([I-D.ietf-v6ops-isp-scenarios-analysis], section 5.4).
The tunnel set-up protocol must be instrumentable to enable the
collection of usage data that can be used, for example, for capacity
5.6 Phase Out
This assisted tunneling mode is only a transition mechanism to enable
ISP to jump start IPv6 service without requiring an immediate global
upgrade of access networks and instead enabling a progressive roll
out. Once IPv6 is available natively in the access network
connecting a customer, there is no reason to keep using tunnels. So
the implementation SHOULD should have a provision to enable the ISP to
signal the user to use native IPv6 instead.
The protocol MUST must be extensible to support tunnel encapsulation other
than IPv6 over IPv4 and IPv6 over transport over IPv4. In
particular, encapsulation of IPv4 over IPv6 (section 7
[I-D.ietf-v6ops-isp-scenarios-analysis], section 7 [RFC3904], section
6 [I-D.ietf-v6ops-ent-analysis]) or IPv6 over IPv6 could be defined.
5.10 DNS considerations
It should be possible to have the server side of the protocol
automatically register the assigned IPv6 address in the DNS system
(AAAA and PTR records) using the ISP name space. Nothing specific is
required in the protocol to support this. The details can be
If stable prefix delegation is done, it is expected that the DNS
delegation of the associated reverse DNS zone will be also stable and
thus can be performed out of band, so there is no requirement to
perform this delegation at the tunnel set-up time.
6. Compatibility with other Transition Mechanisms
The tunnel set-up protocol is not required to be compatible with TSP
[TSP] or any particular implementation of the tunnel broker model
existing transition mechanism. Although, a great deal of experience
can be drawn from the operation of tunnel brokers currently using the
There is a large number of Teredo clients already deployed, the
tunnel set-up protocol should explore the avenue of providing a
compatibility mode with Teredo, at least in the 'simple' mode
described in section 4. However, it may turn out that supporting a
compatibility mode with Teredo either requires to change the Teredo
specifications and/or implement Teredo on the tunnel server side. In
that case, it might be simpler to say that the compatibility mode
should be manage on the client side instead of the server side, that
is leave it up to the client to use either one of them.
Similar considerations as Teredo, section 6.2, applies to Isatap.
However, as Isatap can not work accross NAT, it is of much less
interest in the framework of this document. [I-D.blanchet-v6ops-tunnelbroker-tsp].
7. Security Considerations
The establishment of a tunnel can be compared to Mobile IP
technology, where traffic can be redirected to go from one place to
another one. So similar threats exists. In particular, when a
customer is asking for the set-up of a tunnel ending at IP address X,
the ISP should check:
o the customer is allowed to set-up this tunnel, i.e. he "owns" the
o the customer is allowed to terminate the tunnel where he said he
would, i.e. he "owns" the IPv4 tunnel endpoint.
The first check is simply an authentication issue. The second may be more complex, but can be omitted if strict ingress filtering
complex. The protocol must make sure that the tunnel is in
place in established
to the access network, i.e. legitimate and authenticated destination. IPv4 return
routability checks could help this validation. Also, when the customer user
prevented within the ISP access network, strict ingress filtering can help
prevent IPv4 address spoofing.
This draft has greatly benefited from substantial inputs by Pekka
The following people provided feedback on this work (in no particular
order): Carl Williams, Brian Carpenter, Christian Huitema, Jordi
Palet, Jeroen Massar, Erik Nordmark, Soohong Daniel Park, Suresh
Satapati, Fred Tremplin, Karim El-Malki, Tim Chown, Gert Doering,
Thanks to Mark Prior and Bernard Tuy for providing input from sending packet with an IPv4 source address he does not
See section 4.4 for specific security consideration in the non-
8. Acknowlegements ISP
perspective to validate many requirements.
9. Author Addresses
SUN Microsystems, Inc
17 Network circle UMPK17-202
Menlo Park, CA, 94025
2875 boul. Laurier, bureau 300
Sainte-Foy, QC G1V 2M2
9.1 Normative References
Bound, J., "IPv6 Enterprise Network Analysis",
draft-ietf-v6ops-ent-analysis-00 (work in progress),
Lind, M., Ksinant, V., Park, S., Baudot, A. and P. Savola,
"Scenarios and Analysis for Introducing IPv6 into ISP
(work in progress), June 2004.
[RFC2119] Bradner, S., "Key Words words for Use use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3053] Durand, P. A., Fasano, I. P., Guardini, I. and D. Lento., Lento, "IPv6
Tunnel Broker", RFC 3053, January 2001.
[ISP] Lind, M., "Scenarios and Analysis for Introducing IPv6
into ISP Networks",
draft-ietf-v6ops-isp-scenarios-analysis-01 (work in
progress), February 2004.
[RFC3904] Huitema, C., Austein, R., Satapati, S. and R. van der Pol,
"Evaluation of IPv6 Transition Mechanisms for Unmanaged
Networks", draft-ietf-v6ops-unmaneval-01 RFC 3904, September 2004.
9.2 Informative References
Parent, F. and M. Blanchet, "IPv6 Tunnel Broker with the
Tunnel Setup Protocol(TSP)",
draft-blanchet-v6ops-tunnelbroker-tsp-01 (work in
progress), February June 2004.
[3GPP] J. Wiljakka, "Analysis on
Huitema, C., "Teredo: Tunneling IPv6 Transition in 3GPP Networks",
draft-ietf-v6ops-3gpp-analysis-09 over UDP through
NATs", draft-huitema-v6ops-teredo-02 (work in progress), March
11. Informative References
 Leach, P. and C. Newman, "Using Digest Authentication as a SASL
Mechanism", RFC 2831, May 2000.
 Myers, J., "Simple Authentication and Security Layer (SASL)",
RFC2222, October 1997.
Templin, F., Gleeson, T., Talwar, M. and D. Thaler,
"Intra-Site Automatic Tunnel Addressing Protocol
(ISATAP)", draft-ietf-ngtrans-isatap-21 draft-ietf-ngtrans-isatap-22 (work in
progress), April May 2004.
[TEREDO] Huitema, C., "Teredo:
Palet, J. and M. Diaz, "Evaluation of v6ops Auto-discovery
for Tunneling IPv6 over UDP through
NATs", draft-huitema-v6ops-teredo-01 Mechanisms",
draft-palet-v6ops-tun-auto-disc-01 (work in progress),
[TSP] Blanchet, M., "IPv6 Tunnel Broker with the Tunnel Setup
Tschofenig, H., "Using IPsec to Secure IPv6-over-IPv4
Tunnels", draft-tschofenig-v6ops-secure-tunnels-01 (work
in progress), February July 2004.
Appendix 1. Summary of
[RFC2222] Myers, J., "Simple Authentication and Security Layer
(SASL)", RFC 2222, October 1997.
[RFC2401] Kent, S. and R. Atkinson, "Security Architecture for the Protocol Requirements
The non registered mode:
- MUST be supported by
Internet Protocol", RFC 2401, November 1998.
[RFC2831] Leach, P. and C. Newman, "Using Digest Authentication as a
SASL Mechanism", RFC 2831, May 2000.
2875 boul. Laurier, suite 300
Sainte-Foy, QC G1V 2M2
17 Network circle UMPK17-202
Menlo Park, CA 94025
France Telecom R&D
42, rue des coutures
Appendix A. Changes from version 00
o Non-registered mode removed (now covered in generic zero-conf
tunneling draft). Text throughout the protocol to be designed
- RECOMMENDED to be implemented on client and servers/brokers
- implementation SHOULD turn it on be default
- implementation MUST allow it document changed to be turned off
- MUST support single address assignment
- SHOULD support stable IPv6 address
- MAY support prefix delegation
The registered mode:
- MUST be supported by the protocol
- RECOMMENDED reflect
o Renamed title from "requirements" to be implemented on clients and servers/brokers
- implementation SHOULD turn it off "goals"
o Changed imperatives to lowercase
o /128 endpoints replaced by default
- implementation MUST allow it to be turned on
- MUST support single address assignment
- MUST support stable IPv6 address
- MUST support prefix delegation, SHOULD be able /64
o Removed DNS considerations
o Added many references to turn off
The registered part of other v6ops scenario documents
o Removed the appendix on protocol SHOULD not be too different from
the non registered one, so as requirements summary
o Removed references to minimize code difference between the
12. Full Copyright Statement 3GPP scenario
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