Network Working Group L. Eggert
Internet-Draft P. Sarolahti
Intended status: Informational R. Denis-Courmont
Expires: January 10, 2008 V. Stirbu
Nokia
H. Tschofenig
Nokia Siemens Networks
July 9, 2007
A Survey of Protocols to Control Network Address Translators and
Firewalls
draft-eggert-middlebox-control-survey-01.txt
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Abstract
This document surveys existing protocols for the control of network
address translators and firewalls. It includes standards-level
protocols developed by the IETF and other standards organizations, as
well as protocols designed by individuals.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Protocol Classification . . . . . . . . . . . . . . . . . . . 4
3. SOCKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4. NSIS - NAT/Firewall Signaling Layer Protocol . . . . . . . . . 7
5. MIDCOM - Managed Objects for Middlebox Communication . . . . . 11
6. SIMCO - NEC's Simple Middlebox Configuration Protocol . . . . 11
7. Diameter Gq', Rx+, Gx+ . . . . . . . . . . . . . . . . . . . . 11
8. UPnP - Internet Gateway Device Standardized Device Control
Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
9. NAT-PMP - NAT Port Mapping Protocol . . . . . . . . . . . . . 13
10. STUN - Controlling NAT Bindings using STUN . . . . . . . . . . 14
11. RSIP - Realm-Specific IP . . . . . . . . . . . . . . . . . . . 14
12. ALD - Application Listener Discovery for IPv6 . . . . . . . . 14
13. NLS - Network Layer Signaling Transport Layer . . . . . . . . 15
14. AFWC - Authorized IP Firewall Control Application . . . . . . 15
15. Security Considerations . . . . . . . . . . . . . . . . . . . 15
16. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
17. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16
18. Informative References . . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18
Intellectual Property and Copyright Statements . . . . . . . . . . 20
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1. Introduction
Network address translators (NATs) and firewalls - frequently
referred to as "middleboxes" - are a subject of active discussion in
the IETF and related development and standardization communities.
These devices are not part of the traditional end-to-end Internet
architecture, because they usually operate on transport- and higher-
layer information inside the network, which is a layering violation
in the original architecture, because operating on that information
was the exclusive providence of the end-hosts.
However, in practice, NATs have turned out to be necessary to be able
to mitigate the IPv4 address space limitations of many network
domains. Similarly, because the networking software in many systems
has turned out to contain security defects of different kinds, use of
firewalls is common to protect the systems from attacks coming from
the network. Another motivation for firewalls is to protect against
the abuse of possibly scarce of expensive bandwidth, for example,
unwanted traffic on wireless links.
A shared disadvantage of NATs and firewalls is that they often encode
knowledge about a particular set of higher-layer protocols and
applications in order to operate. This practice prevents new types
of network protocols or applications from being deployed end-to-end,
unless the middleboxes are upgraded or reconfigured as well. For
example, a firewall is usually configured with a list of ports for a
set of common network applications, preventing introduction of new
applications. Furthermore, they commonly only support traditional
transport protocols, such as TCP and UDP, preventing the use of other
protocols, such as IPsec, IP tunneling, or other transport protocols.
In addition, many NATs and firewalls maintain some state for each
active transport-layer session that typically needs to be refreshed
in constant intervals, and can be initiated only by certain hosts.
The IETF is currently developing recommendations for the operation of
NATs in the BEHAVE working group. These recommendations provide
guidelines for how NATs should translate a number of common
protocols, including TCP [I-D.ietf-behave-tcp], UDP [RFC4787], ICMP
[I-D.ietf-behave-nat-icmp] and IP multicast
[I-D.ietf-behave-multicast]. Other organizations are developing
similar guidelines. One example are Microsoft's requirements for the
"Works with Windows Vista" and "Certified for Windows Vista" logo
program [VISTALOGO] (see page 121 to page 132).
Even if these efforts result in more unified behavior of middleboxes,
they will not necessarily overcome the above-mentioned limitations:
different protocols and applications will still need to adapt to the
behavior of NATs and firewalls. Commonly, new protocols must be
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encapsulated into UDP packets in order to pass through these devices.
Although the UDP header and protocol logic are minimal and do not
consume much network capacity, the use of UDP causes other problems,
because it is not connection-oriented. Because there are no messages
for connection establishment or connection tear-down in UDP, a
stateful NAT or firewall needs to monitor ongoing UDP traffic between
a source and destination, and in the absence of such traffic assumes
that the session has ended, removing the related session state. In
practice, the timers for state clean-up have turned out to be short
(on the order of seconds), requiring the end hosts to transmit
frequent and resource-consuming keep-alive messages to refresh the
session state maintained at middleboxes.
A more advanced method to overcome the limitations caused by NATs or
firewalls would be to allow end-hosts to signal their communication
characteristics and profiles explicitly to the NATs and firewalls, or
alternatively to allow these devices to signal their configuration
information to the end-hosts. With such schemes, the number of
state-refreshing keep-alives could be significantly reduced, and NATs
and firewalls could be made directly aware of the communication
characteristics of the end-hosts.
A number of existing protocols have been proposed for this purpose,
and new proposals are being prepared. This document aims to support
such efforts by surveying existing proposals and by discussing the
the benefits and shortcomings of these schemes.
2. Protocol Classification
This section categorizes the proposals into clusters to illustrate
the major design choices.
o End-System-Initiated Protocols
* Two Party Approach
+ UPnP (Section 8)
+ NAT-PMP (Section 9)
* Multi-Party Approach
+ STUN controlled NAT (Section 10)
+ NLS (Section 13)
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+ NSIS NATFW NSLP (Section 4)
o Third-Party-Initiated Approaches
* Diameter Gq', Rx+, Gx+ (Section 7)
* SIMCO (Section 6)
* MIDCOM (Section 5)
A reasonable classification of RSIP (Section 11), ALD (Section 12),
SOCKS (Section 3) and AFWC (Section 14) is still pending.
The following document were (or are being) developed within the IETF:
o SOCKS Section 3
o NSIS NATFW NSLP, Section 4
o MIDCOM - Managed Objects for Middlebox Communication, Section 5
o SIMCO - NEC's Simple Middlebox Configuration Protocol, Section 6
These protocols were developed outside the IETF:
o UPnP - Internet Gateway Device Standardized Device Control
Protocol (Section 8)
o Diameter Gq', Rx+, Gx+ (Section 7)
The following protocols are proposals by individuals:
o NAT-PMP - NAT Port Mapping Protocol (Section 9)
o STUN - Controlling NAT Bindings using STUN (Section 10)
o RSIP - Realm-Specific IP (Section 11)
o ALD - Application Listener Discovery for IPv6 (Section 12)
o NLS - Network Layer Signaling Transport Layer (Section 13)
o AFWC - Authorized IP Firewall Control Application (Section 14)
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3. SOCKS
3.1. Protocol Overview
The SOCKS Protocol Version 5 [RFC1928] defines a method for nodes
located on an IP network (such as an Intranet with no routing to the
Internet) to establish TCP sessions and exchange UDP datagrams with
another IP network (usually the global Internet). To that end, a
SOCKS server must be located on the boundary of both networks, and
SOCKS clients must explicitly request the server to relay their
communication sessions.
When a SOCKS client establishes a TCP session to the remote network,
it first connects to the SOCKS server on a well-known TCP port,
sending a connection request with optional authentication
credentials. The request specifies in which direction the TCP
session is to be established, i.e., whether the SOCKS server will act
as the active or passive endpoint. The SOCKS server, if it accepts
the request, informs the client of the external IP address and TCP
port number that it will use. If the SOCKS server acts as the
passive endpoint, it sends an additional response once the TCP three-
way handshake is completed. The SOCKS server then forwards traffic
between the internal and external TCP sessions, until either of them
is terminated.
UDP sessions are also initially negotiated via a TCP session to the
SOCKS server, in a similar manner. If successful, the client obtains
the IP address and UDP port number of a UDP relay server. The relay
forwards UDP datagrams between the local and remote networks. When
sending a datagram, the client adds an additional, SOCKS-specific
header, which carries the IP address or DNS name of the remote peer
and the intended destination UDP port number of the datagram. The
relay adds the same header when forwarding datagrams from the remote
network back to the client.
3.2. Protocol Analysis
The SOCKS protocol makes few assumptions about the network
environment it operates in. In particular, there can be any number
NAT/firewall devices between the client and the SOCKS server, and
there need not be a router between the local and remote networks. It
is assumed that the SOCKS server itself can freely exchange TCP and
UDP packets with the remote network.
SOCKS supports both IPv4 and IPv6 as well as translation from one to
the other. SOCKS only supports UDP and TCP as transport protocols.
Conveyance of IP header parameters other than the IP addresses (such
as IP options, hop limit, TOS field, etc.) are not defined. SOCKS
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cannot be used for generic server applications: only one passive TCP
session per request is allowed.
The protocol is mature and implementations for clients and servers
are widely available. SOCKS is supported in many FTP and HTTP
clients. Applications must usually be modified to support SOCKS, but
it is also possible to implement SOCKS transparently as a shim layer
above the BSD socket API.
SOCKS requires manual configuration on the client. SOCKS server
address and optional credentials must be explicitly provisioned.
4. NSIS - NAT/Firewall Signaling Layer Protocol
4.1. Protocol Overview
NSIS uses a two-layer architecture with one lower-layer transport
(NTLP) and multiple upper-layer application signaling protocols
(NSLPs). This section first discusses the generic properties of the
NTLP transport and then the specific characteristics of the NAT/
Firewall signaling protocol built upon it.
GIST [I-D.ietf-nsis-ntlp] establishes NTLP "routing" state that
allows signaling messages to be routed forwards and backwards along a
path. GIST also provides two ways to send signaling messages:
1. An RSVP-like signaling style with end-to-end addressed messages
that contain the source and the destination IP addresses of the
data flow. The messages are intercepted along the path by NSIS
nodes interested in these messages (by using Router Alert
Options). The GIST specification refers to this as the Datagram
mode (D-mode).
2. Connection mode (or C-mode) is used when NSIS nodes are directly
addressed. This mode assumes that the discovery procedure has
already finished (or the address of the receiving node is known
via other means) and information about the node is already
available.
An important part of GIST is its discovery mechanism. As an outcome
of the discovery procedure the querying node learns the address of
the responding node, its capability and establishes GIST routing
state.
Once the next NSIS aware node is known, a messaging association can
be established between these two nodes using C-mode. The same
procedure is repeated again and again for the C-Mode until the last
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GIST node is reached.
The NAT/Firewall NSLP description [I-D.ietf-nsis-nslp-natfw] defines
an NSIS Signaling Layer Protocol (NSLP) for configuration of network
address translators and firewalls on top of GIST.
The NATFW NSLP uses GIST as a transport for its signaling messages.
Objects about a created NAT binding, as well as lifetime and
signaling information (such as protocol headers and error messages)
are contained in a NATFW NSLP message itself. All other information
about the flow identifier and the session identifier is carried in
GIST. For communication security between neighboring NATFW NSLP
nodes the usage of Transport Layer Security (TLS) is specified. The
usage of an authorization token is possible
[I-D.manner-nsis-nslp-auth]
It is useful to distinguish between two signaling modes:
The first mode (CREATE) is the traditional way of creating a NAT
binding by sending a message from the data sender along the path
to the data receiver. Figure 1 shows a message exchange for this
signaling mode.
The second mode (EXTERNAL) is used when a data receiver is behind
a NAT and wants to establish a NAT binding to allow incoming data
traffic. Figure 2 shows this mode. It was necessary to introduce
this mode, because of an end-to-end reachability problem.
Furthermore, it provides a transition scenario where the data
receiver behind a NAT or a firewall is able to configure their
middlebox locally.
Private Address Public Address
+----------+ Space +----------+ Space +----------+
| Data | | NAT | | Data |
| Sender | | | | Receiver |
+----------+ +----------+ +----------+
| | |
| CREATE | CREATE |
|----------------------------->+--------------------------->|
| | |
| RESPONSE | RESPONSE |
|<-----------------------------+<---------------------------|
| | |
============================================================>
Direction of data traffic
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Figure 1: The NATFW NSLP CREATE Mode
With the CREATE mode shown in Figure 1 the data sender (which happens
to be the NSIS initiator in this case) sends a message to request a
NAT binding to be created. The message is targeted to the data
receiver, which returns a success or failure in the RESPONSE message.
The data sender learns about the new NAT binding with information
carried in the RESPONSE message.
Public Internet Private Address
+----------+ +----------+ Space +----------+
| Data | | NAT | | Data |
| Sender | | | | Receiver |
+----------+ +----------+ +----------+
| | |
| | EXTERNAL |
| |<---------------------------|
| | |
| | RESPONSE |
| |--------------------------->|
| | |
============================================================>
Direction of data traffic
Figure 2: The NATFW NSLP EXTERNAL Mode
With the EXTERNAL mode shown in Figure 2 the data receiver behind a
NAT creates a NAT binding. This allows data traffic from a node on
the Internet to be received. Please note that the EXTERNAL message
is sent in the opposite direction of the data traffic.
4.2. Protocol Analysis
This section discusses the pros and cons of the protocol.
Is the protocol is restricted to certain applications or network
environments?
The usage of the protocol is not restricted to a specific environment
but to take advantage of its features it is necessary that Network
Address Translators and firewalls implement this protocol.
Does it require additional infrastructure, lower-layer features or
cooperation from other entities?
While the protocol supports a zero-configuration scheme so that it
works in almost network topologies. The protocol works with multiple
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nested NATs and firewalls unless the data receiver is behind a
complex network topology combined with routing asymmetry (without)
state synchronization between the edge firewalls when the data sender
does not support the protocol as well.
To make use of the security functionality and to perform meaningful
authorization capabilities it is, however, necessary to have some
form of security infrastructure in place. The protocol provides a
very flexible security model with support in different security
architectures.
Furthermore,for the EXTERNAL signal mode to work it is necessary that
the edge firewall or edge NAT towards the public Internet terminates
the signaling message exchange since the message might be targeted
towards an address that does not exist.
Does it require modifications to applications?
The protocol can be used in a proxy mode where no end host support is
necessary. In order to benefit best from the supported functionality
is is advisable to make applications aware of the capability.
How mature is the specification? Has the protocol seen any use or
deployment?
The specification is passed Working Group Last Call and several
implementations (including open source implementations) exist.
However, the protocol is not deployed yet.
How does the client discover the middlebox?
The middlebox discovery is accomplished as part of the functionality
provided in GIST, namely specifically crafted packets that look like
data packets are used. These discovery packets are marked with a
router alert option and they are intercepted by firewalls and NATs
along the path.
What kinds of "pinholes" does the protocol support?
The protocol supports a long range of pinholes. The complete list
can be found in Section 5.8.1.1 of GIST.
What kinds of prior security arrangements does the protocol
assume?
When client authentication is required then the credentials of a
ciphersuite available for TLS need to be available to the end host.
The security architecture builds on a hop-by-hop security
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architecture. Alternatively, the usage of an authorization token is
possible. Authorization tokens can also be used in a non-hop-by-hop
fashion.
The security architecture is meant to provide strong security
protection rather than opportunistic security mechanisms. Further
security mechanisms can be added without the need to re-define the
protocol by plugging new security functionality into GIST or the
NATFW NSLP and my making use of the initial capability exchange.
Does it work if routers (not supporting this protocol) somewhere
drop packets with IP options?
GIST and the NATFW NSLP has problems if routers drop packets marked
with the Router Alert option. It is, however, possible to extend
GIST with a different path-coupled signaling procedure.
Does the protocol allow running a general-purpose server behind
the NAT/firewall?
Yes.
5. MIDCOM - Managed Objects for Middlebox Communication
To be completed [RFC3303].
6. SIMCO - NEC's Simple Middlebox Configuration Protocol
To be completed [RFC4540].
7. Diameter Gq', Rx+, Gx+
To be completed [need reference].
8. UPnP - Internet Gateway Device Standardized Device Control Protocol
8.1. Protocol Overview
The Internet Gateway Device (IGD) is an "edge" interconnection device
between a residential Local Area Network (LAN) and a Wide Area
Network (WAN), providing connectivity to the Internet for the
networked devices in the residential network. The IGD could be
physically implemented as a dedicated, standalone device or modeled
as a set of Universal Plug-and-Play (UPnP) devices and services on a
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personal computer.
As an UPnP-based protocol, the IGD Standardized Device Control
Protocol [UPNP] inherits the features that the UPnP Device
Architecture provides for support zero-configuration, "invisible"
networking, and automatic discovery for a breadth of device
categories. Any device can dynamically join a network, obtain an IP
address, announce its name, convey its capabilities upon request, and
learn about the presence and capabilities of other devices. Devices
can disconnect from the network automatically without leaving any
unwanted state information behind.
The IGD Standardized Device Control Protocol contains a set of
devices and services that allow clients (in the UPnP context also
called "Control Points") to control the initiation and termination of
connections, monitor status and events of connections, or manage host
configuration services, e.g., DHCP or Dynamic DNS. Among these
services, the "WANIPConnection" service provides the functionality
that allows the Control Points to manage the network address
translation on the IGD device.
The IGD Standardized Device Control Protocol preserves the ability of
non-UPnP devices to initiate and/or share Internet access.
8.2. Protocol Analysis
The IGD Standardized Device Control Protocol is intended to be used
in unmanaged network environments such as those found typically in
residential networks. The residential network can have up to four
segments, a limitation inherited from the UPnP Device Architecture,
because the TTL value for the link-local multicast discovery messages
is four.
By design, the protocol does permit the presence of several
residential gateways in the same network and also permits residential
gateways to have multiple connections to the Internet. In practice,
a lack of routing mechanisms across multiple, simultaneously active
WAN connections on multiple WAN interfaces and related issues caused
by multiple, simultaneously active Internet Gateway devices (e.g.,
default gateway conflict resolution, load balancing or fail over)
make scenarios other than that of a single Gateway Device with a
single Internet connection difficult to support.
A residential gateway supporting the IGD Standardized Device Control
Protocol is able to operate in two modes. In "routed mode", the
gateway shares the routable WAN IP address with the control points on
the LAN using NAT. In "bridged" mode, all Ethernet packets from
devices on the LAN are bridged to the WAN. In scenarios where the IP
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address on the WAN interface is not routable, the device can be
switched from routed to bridged mode, allowing both the discovery of
IGD Standardized Device Control Protocol devices further along the
path as well as the use of other NAT hole-punching protocols.
Applications that intend to create port mappings on a residential
gateway supporting the IGD Standardized Device Control Protocol need
to have embedded control point functionality, enabling them to create
port mappings from TCP or UDP port on the external IPv4 address to
the corresponding ports on the internal IPv4 addresses.
The protocol is implemented in more than 90% of the consumer routers,
although the functionality might not be enabled by default.
9. NAT-PMP - NAT Port Mapping Protocol
9.1. Protocol Overview
The NAT Port Mapping Protocol [I-D.cheshire-nat-pmp] is a light-
weight binary protocol running on top of UDP between client hosts and
their IPv4 gateway. Clients can send requests to their first-hop
gateway on a well-known UDP port, in order to determine whether NAT-
PMP is supported. If that is the case, they will also learn the
external IPv4 address of the gateway device.
If the gateway supports NAT-PMP, a host can assume that it is behind
a NAT and start sending request for mapping of external TCP or UDP
ports on the external IPv4 address. Mappings can be destroyed
explicitly. They also automatically expire after a timeout that can
be negotiated per mapping, unless refreshed.
Through the use of link-local multicast, the gateway can notify hosts
if its external IP changes, and/or if it has rebooted. In the latter
case, hosts are expected to recreate any mappings. This procedure
attempts to protect against loss of state at the gateway.
NAT-PMP assumes that there is one and only one NAT along the path,
which also has to be the first-hop gateway. A gateway must not
enable NAT-PMP if it is does not perform address/port translation.
9.2. Protocol Analysis
NAT-PMP is applicable to small, unmanaged, non-routed networks,
connecting multiple hosts to the IPv4 Internet through a single
public IPv4 address. It does not require any configuration. Support
from the gateway can be auto-detected by clients, and the trust model
is solely based on network attachment. There is no support for IPv6,
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nor is there support for transport protocols other than TCP or UDP.
Nested NATs and non-NAT'ing firewalls are not supported.
NAT-PMP covers the same use cases as [UPNP], although it is not as
widely deployed today. (NAT-PMP is currently mostly implemented by
equipment from Apple Computer, Inc.). The specification is recent,
but nevertheless mature.
Applications will normally need to be modified to explicitly request
port mappings from the operating system, which would then operate the
NAT-PMP state machine and message handling. By design, the protocol
allows applications to expose services to the outside, so hole-
punching could conceivably be done automatically whenever an
application listens to a local TCP port (although this would probably
have unwelcome security implications).
10. STUN - Controlling NAT Bindings using STUN
To be completed [I-D.wing-behave-nat-control-stun-usage].
11. RSIP - Realm-Specific IP
To be completed [RFC3103].
12. ALD - Application Listener Discovery for IPv6
12.1. Protocol Overview
Application Listener Discovery for IPv6 [I-D.woodyatt-ald] is a
light-weight, binary protocol to explicitly punch holes through
stateful IPv6 firewalls. It uses ICMPv6 for signaling and is auto-
configured through an explicit ICMPv6 router advertisement option.
If the gateway supports ALD, a host can request the opening of holes
for any incoming packet toward its own IPv6 address, based on one of
multiple possible criteria:
o always
o an IP protocol (excluding IPv6 extension headers)
o for any standard transport protocol, a destination port number
o for IPsec ESP, an SPI value
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Holes automatically expire if not refreshed before a negotiated
timeout. The gateway can additionally notify hosts through
unsolicited advertisements if it has rebooted or lost state.
12.2. Protocol Analysis
ALD is aimed at unmanaged IPv6 networks, where it might not be
acceptable to pass any unsolicited packets coming from the outside
toward any hosts in the internal network. ALD needs support from all
IPv6 routers within the network, because clients learn the ALD
middlebox address through IPv6 Neighbor Discovery auto-configuration.
It is expected that ALD will operate on the router itself in most
cases. As with IPv6 Neighbor Discovery, there is no authentication.
The specification is currently a work-in-progress; there is no known
deployment to date. Applications would supposedly need slight
modifications, similar as with [UPNP] or [I-D.cheshire-nat-pmp].
ALD can handle "pinholes" for any transport protocol, although it is
limited to IPv6 networks, and is meant to restore the ability to
operate general-purpose servers behind stateful firewalls. It
currently does not explicitly support nesting, though ALD middleboxes
could probably forward pinholes request in a hierarchical manner
(from innermost to outermost device).
13. NLS - Network Layer Signaling Transport Layer
To be completed [I-D.shore-nls-fw].
14. AFWC - Authorized IP Firewall Control Application
To be completed [I-D.shore-afwc].
15. Security Considerations
This document is a survey of existing protocols and does not raise
any new security considerations. The security considerations of the
surveyed protocols are discussed in their respective specifications,
at least for protocols developed within the IETF.
16. IANA Considerations
This document raises no IANA considerations.
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17. Acknowledgments
The authors would like to thank Pasi Eronen, Albrecht Schwarz and Dan
Wing for their comments on this document.
Dave Thaler provided information on the "Works with Windows Vista"
and "Certified for Windows Vista" logo program [VISTALOGO].
18. Informative References
[I-D.cheshire-nat-pmp]
Cheshire, S., "NAT Port Mapping Protocol (NAT-PMP)",
draft-cheshire-nat-pmp-02 (work in progress),
October 2006.
[I-D.ietf-behave-multicast]
Eckert, T. and D. Wing, "IP Multicast Requirements for a
Network Address (and port) Translator (NAT)",
draft-ietf-behave-multicast-08 (work in progress),
July 2007.
[I-D.ietf-behave-nat-icmp]
Srisuresh, P., "NAT Behavioral Requirements for ICMP
protocol", draft-ietf-behave-nat-icmp-04 (work in
progress), July 2007.
[I-D.ietf-behave-tcp]
Guha, S., "NAT Behavioral Requirements for TCP",
draft-ietf-behave-tcp-07 (work in progress), April 2007.
[I-D.ietf-nsis-nslp-natfw]
Stiemerling, M., "NAT/Firewall NSIS Signaling Layer
Protocol (NSLP)", draft-ietf-nsis-nslp-natfw-14 (work in
progress), March 2007.
[I-D.ietf-nsis-ntlp]
Schulzrinne, H. and R. Hancock, "GIST: General Internet
Signalling Transport", draft-ietf-nsis-ntlp-13 (work in
progress), April 2007.
[I-D.manner-nsis-nslp-auth]
Manner, J., "Authorization for NSIS Signaling Layer
Protocols", draft-manner-nsis-nslp-auth-03 (work in
progress), March 2007.
[I-D.shore-afwc]
Shore, M. and D. McGrew, "An Authorized IP Firewall
Eggert, et al. Expires January 10, 2008 [Page 16]
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Control Application", draft-shore-afwc-00 (work in
progress), September 2006.
[I-D.shore-nls-fw]
Shore, M., "The NLS Firewall Application",
draft-shore-nls-fw-00 (work in progress), February 2006.
[I-D.wing-behave-nat-control-stun-usage]
Wing, D. and J. Rosenberg, "Discovering, Querying, and
Controlling Firewalls and NATs using STUN",
draft-wing-behave-nat-control-stun-usage-02 (work in
progress), June 2007.
[I-D.woodyatt-ald]
Woodyatt, J., "Application Listener Discovery (ALD) for
IPv6", draft-woodyatt-ald-01 (work in progress),
June 2007.
[RFC1928] Leech, M., Ganis, M., Lee, Y., Kuris, R., Koblas, D., and
L. Jones, "SOCKS Protocol Version 5", RFC 1928,
March 1996.
[RFC3103] Borella, M., Grabelsky, D., Lo, J., and K. Taniguchi,
"Realm Specific IP: Protocol Specification", RFC 3103,
October 2001.
[RFC3303] Srisuresh, P., Kuthan, J., Rosenberg, J., Molitor, A., and
A. Rayhan, "Middlebox communication architecture and
framework", RFC 3303, August 2002.
[RFC4540] Stiemerling, M., Quittek, J., and C. Cadar, "NEC's Simple
Middlebox Configuration (SIMCO) Protocol Version 3.0",
RFC 4540, May 2006.
[RFC4787] Audet, F. and C. Jennings, "Network Address Translation
(NAT) Behavioral Requirements for Unicast UDP", BCP 127,
RFC 4787, January 2007.
[UPNP] UPnP Forum, "Internet Gateway Device (IGD) Standardized
Device Control Protocol V 1.0", November 2001.
[VISTALOGO]
Microsoft Corporation, "Windows Logo Program Device
Requirements for Windows Vista Client and Windows Server
code named 'Longhorn' (Version 3.09)", December 2006.
Eggert, et al. Expires January 10, 2008 [Page 17]
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Authors' Addresses
Lars Eggert
Nokia Research Center
P.O. Box 407
Nokia Group FIN-00045
Finland
Phone: +358 50 4824461
Email: lars.eggert@nokia.com
URI: http://research.nokia.com/people/lars_eggert/
Pasi Sarolahti
Nokia Research Center
P.O. Box 407
Nokia Group FIN-00045
Finland
Phone: +358 50 4876607
Email: pasi.sarolahti@nokia.com
URI: http://www.iki.fi/pasi.sarolahti/
Remi Denis-Courmont
Nokia Technology Platforms
P.O. Box 407
Nokia Group FIN-00045
Finland
Phone: +358 50 4876315
Email: remi.denis-courmont@nokia.com
URI: http://www.remlab.net/
Vlad Stirbu
Nokia Technology Platforms
P.O. Box 407
Nokia Group FIN-00045
Finland
Phone: +358 50 3860572
Email: vlad.stirbu@nokia.com
Eggert, et al. Expires January 10, 2008 [Page 18]
Internet-Draft Survey of Middlebox Control Protocols July 2007
Hannes Tschofenig
Nokia Siemens Networks
Otto-Hahn-Ring 6
Munich, Bavaria 81739
Germany
Email: hannes.tschofenig@nsn.com
URI: http://www.tschofenig.com/
Eggert, et al. Expires January 10, 2008 [Page 19]
Internet-Draft Survey of Middlebox Control Protocols July 2007
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Eggert, et al. Expires January 10, 2008 [Page 20]