ISO/IEC 29341-18-1:2011

Information technology - UPnP Device Architecture - Part 18-1: Remote Access Device Control Protocol - Remote Access Architecture

ISO/IEC 629431-18-1:2011(E) describes an architecture that provides the infrastructure that allows generic UPnP devices, services and control points deployed in remote physical devices to interact with the corresponding UPnP devices, services and control points physically attached to the home network. The mechanisms defined in this architecture will allow to extend the home network so that it will logically include the remote devices so that all devices will be able to communicate among themselves using the UPnP Forum defined mechanisms, e.g. UDA. The desired behaviour of the interactions between the remote device and home devices is envisioned to be similar with the one expected as if all devices are located in the same local area network.

General Information

• Status: Published
• Publication Date: 29-Aug-2011
• ICS: 35.200 - Interface and interconnection equipment
• Technical Committee: ISO/IEC JTC 1 - Information technology
• Current Stage: PPUB - Publication issued
• Start Date: 29-Aug-2011
• Completion Date: 30-Nov-2011

Overview

ISO/IEC 29341-18-1:2011 - “Information technology - UPnP Device Architecture - Part 18-1: Remote Access Device Control Protocol - Remote Access Architecture” defines an architecture and infrastructure to enable UPnP devices, services and control points deployed on remote physical devices to interact with UPnP devices on a home network as if they were on the same LAN. The standard describes how to logically extend a home network to include remote devices using established mechanisms while preserving consistent behavior across different bridging models.

Key topics and technical requirements

• Remote Access Paradigm: Defines the overall architecture that connects remote and home network segments and allows multiple bridging models to be plugged into a consistent interface.
• Functional components: Describes components such as the Remote Access Client (RAC), Remote Access Server (RAS), Remote Access Discovery Agent (RADiscoveryAgent), Remote Access Transport Agent, and RADA (Remote Access Device Agent) and their roles in discovery, synchronization and transport.
• Phased operation: Specifies Setup, Operational and Management phases - including configuration, connection establishment, discovery synchronization, heartbeat, timeout and administrative shutdown behaviors.
• Inbound connection configuration: Addresses the mechanisms for enabling inbound access into the home network (references InboundConnectionConfig service).
• Network considerations: Discusses IPv4/IPv6 addressing, NAT traversal issues, STUN-like configurations, server name resolution and detection of NAT type on the server side.
• Behavioral requirements: Uses RFC 2119 keywords (MUST/SHOULD/MAY) to define required, recommended and optional behaviors for interoperability and security.
• Interoperability constraints: The architecture enforces uniform behavior but explicitly does not define interfaces for non‑UPnP “service” gateways.

Practical applications

• Remote control and monitoring of home IoT devices and media devices from cloud-hosted or mobile control points.
• Extending home automation systems to include devices located off‑site (e.g., sensors in a vacation home).
• Remote diagnostics and device management by service providers through a logically extended UPnP domain.
• Enabling media streaming and UPnP AV scenarios where sources or control points are outside the local network.

Who should use this standard

• Consumer router and residential gateway manufacturers implementing UPnP Remote Access features.
• IoT device makers and UPnP device developers requiring standardized remote interaction.
• Network architects and service providers designing remote management, NAT traversal and discovery mechanisms.
• Systems integrators building home automation and remote control solutions.

Related standards

• UPnP Device Architecture (UDA)
• UPnP RA parts and services: InboundConnectionConfig, RAClient, RADAConfig, RADASync, RADiscoveryAgent, RAServer, RATAConfig
• IPv6/IPv4 IP support references (UPnP annexes) and NAT/STUN traversal techniques

Keywords: ISO/IEC 29341-18-1:2011, UPnP Remote Access, Remote Access Architecture, Remote Access Device Control Protocol, UPnP, home network, NAT traversal, IPv6, device discovery.

Standards Content (Sample)

ISO/IEC 29341-18-1
Edition 1.0 2011-08
INTERNATIONAL
STANDARD
colour
inside
Information technology – UPnP device architecture –
Part 18-1: Remote Access Device Control Protocol – Remote Access
Architecture
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about ISO/IEC copyright or have an enquiry about obtaining additional rights to this
publication, please contact the address below or your local IEC member National Committee for further information.

IEC Central Office
3, rue de Varembé
CH-1211 Geneva 20
Switzerland
Email: [e-mail]
Web: www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
 Catalogue of IEC publications: www.iec.ch/searchpub
The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,…).
It also gives information on projects, withdrawn and replaced publications.
 IEC Just Published: www.iec.ch/online_news/justpub
Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available
on-line and also by email.
 Electropedia: www.electropedia.org
The world's leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions
in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical
Vocabulary online.
 Customer Service Centre: www.iec.ch/webstore/custserv
If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service
Centre FAQ or contact us:
Email: [e-mail]
Tel.: [phone]
Fax: [phone]
ISO/IEC 29341-18-1
Edition 1.0 2011-08
INTERNATIONAL
STANDARD
colour
inside
Information technology – UPnP device architecture –
Part 18-1: Remote Access Device Control Protocol – Remote Access
Architecture
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
K
ICS 35.200 ISBN 978-2-88912-648-4

29341-18-1 © ISO/IEC:2011(E)
CONTENTS
1  Overview and Scope . 3
1.1  Notation . 3
1.2  References . 4
1.2.1  Informative References . 4
1.3  Terms and Abbreviations . 5
1.3.1  Abbrevia tions . 5
1.3.2  Terms . 5
2  Introduction . 7
3  Operational Considerations . 7
3.1  Remote Access Environment . 7
3.2  Access Networks . 8
3.2.1  IPv4 Addressing and NAT issues . 9
3.2.2  IPv6 Addressing . 10
3.3  Home Network Environment . 10
3.3.1  IPv4 Support in Home Routers . 10
3.3.2  IPv6 Support in Home Routers . 10
3.4  Support Services in the Public Network . 10
3.4.1  Server Name Resolution . 10
3.4.2  Detecting NAT and NAT Type on Server Side . 10
4  Remote Access Reference Architecture . 11
4.1  Remote Access Architecture Paradigm . 11
4.2  Remote Access Components Overview . 12
4.3  Remote Access Phases Overvi ew . 13
4.3.1  Setup Services . 13
4.3.2  Operational Services . 13
4.3.3  Management Service . 14
4.4  Remote Access Functionalities . 14
4.4.1  Inbound Connection Configuration . 14
4.4.2  Remote Access Discovery Agent . 15
4.4.3  Remote Access Transport Agent . 17
5  Interaction Model . 17
5.1  UPnP RA Setup . 17
5.2  Configure the RAC for Remote Access to Home Network . 18
5.3  Access Home Network Remotely from RAC over the Internet . 18
5.4  UPnP RA Connection Use . 18
5.5  RADA Synchronization Process . 19
5.6  RADA Hear tbeat . 19
5.7  RADA Communication Time- out . 20
5.8  RADA Administrative Shutdown . 20
Annex A Deployment Scenarios . 21
A.1  Intended Deployment Scenarios . 21
A.1.1  Remote Access Server in Residential Gateway . 21
A.1.2  Remote Access Server in a 3rd Party Device . 21
A.1.3  Remote Access Server Hosted by a 3rd Party in the Internet . 21

XXX: © IEC:2010 2 29341-18-1 © ISO/IEC:2011(E)

Figure 2-1 — UPnP Remote Access. . 7
Figure 3-1 — Remote Access Environment. . 8
Figure 3-2 — Access Networks. . 9
Figure 4-1 — Remote Access Architecture Paradigm. . 11
Figure 4-2 — Remote Access Components Overview. . 12
Figure 4-3 — Typical STUN Configuration in Home Networks . 15
Figure 4-4 — Discovery Information Aggregation . 16
Figure 4-5 — Discovery Synchroniza tion . 16
Figure 5-1 — Remote Access Setup. . 17
Figure 5-2 — Configure the RAC for Remote Access to Home Network . 18
Figure 5-3 — Access Home Network Remotely from RAC over the Internet . 18
Figure 5-4 — UPnP RA Connection Use . 18
Figure 5-5 — RADA Synchronization Process . 19
Figure 5-6 — RADA Heartbeat . 19
Figure 5-7 — RADA Communication Time-out . 20
Figure 5-8 — RADA Administrative Shutdown . 20

Table 1-1 — Abbreviati ons . 5

29341-18-1 © ISO/IEC:2011(E)
INFORMATION TECHNOLOGY –
UPNP DEVICE ARCHITECTURE –
Part 18-1: Remote Access Device Control Protocol –
Remote Access Architecture
FOREWORD
1) ISO (International Organization for Standardization) and IEC (International Electrotechnical Commission) form the
specialized system for worldwide standardization. National bodies that are members of ISO or IEC participate in
the development of International Standards. Their preparation is entrusted to technical committees; any ISO and
IEC member body interested in the subject dealt with may participate in this preparatory work. International
governmental and non-governmental organizations liaising with ISO and IEC also participate in this preparation.
2) In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
Draft International Standards adopted by the joint technical committee are circulated to national bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the national bodies casting a vote.
3) The formal decisions or agreements of IEC and ISO on technical matters express, as nearly as possible, an
international consensus of opinion on the relevant subjects since each technical committee has representation
from all interested IEC and ISO member bodies.
4) IEC, ISO and ISO/IEC publications have the form of recommendations for international use and are accepted
by IEC and ISO member bodies in that sense. While all reasonable efforts are made to ensure that the
technical content of IEC, ISO and ISO/IEC publications is accurate, IEC or ISO cannot be held responsible for
the way in which they are used or for any misinterpretation by any end user.
5) In order to promote international uniformity, IEC and ISO member bodies undertake to apply IEC, ISO and
ISO/IEC publications transparently to the maximum extent possible in their national and regional publications.
Any divergence between any ISO/IEC publication and the corresponding national or regional publication
should be clearly indicated in the latter.
6) ISO and IEC provide no marking procedure to indicate their approval and cannot be rendered responsible for
any equipment declared to be in conformity with an ISO/IEC publication.
7) All users should ensure that they have the latest edition of this publication.
8) No liability shall attach to IEC or ISO or its directors, employees, servants or agents including individual experts
and members of their technical committees and IEC or ISO member bodies for any personal injury, property
damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees)
and expenses arising out of the publication of, use of, or reliance upon, this ISO/IEC publication or any other IEC,
ISO or ISO/IEC publications.
9) Attention is drawn to the normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
10) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of
patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
International Standard ISO/IEC 29341-18-1 was prepared by UPnP Forum Steering
committee , was adopted, under the fast track procedure, by subcommittee 25:
Interconnection of information technology equipment, of ISO/IEC joint technical committee 1:
Information technology.
The list of all currently available parts of the ISO/IEC 29341 series, under the general title
Information technology – UPnP device architecture, can be found on the IEC web site.
This International Standard has been approved by vote of the member bodies, and the voting
results may be obtained from the address given on the second title page.

—————————
rd
UPnP Forum Steering committee, UPnP Forum, 3855 SW 153 Drive, Beaverton, Oregon 97006 USA. See also
“Introduction”.
29341-18-1 © ISO/IEC:2011(E)
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.

29341-18-1 XXX: © IEC:2010 © ISO/IEC:2011(E) 3
1 Overview and Scope
This document describes an architecture that provides the infrastructure that allows generic
UPnP devices, services and control points deployed in remote physical devices to interact
with the corresponding UPnP devices, services and control points physically attached to the
home network. The mechanisms defined in this architecture will allow to extend the home
network so that it will logically include the remote devices so that all devices will be able to
communicate among themselves using the UPnP Forum defined mechanisms, e.g. UDA. The
desired behavior of the interactions between the remote device and home devices is
envisioned to be similar with the one expected as if all devices are located in the same local
area network.
In order to accommodate the above mentioned goals, the Remote Access Architecture will
provide means to connect the two segments of the extended home network using established
mechanisms. The architecture recognizes that there might be several possible alternative
models to “bridge” the two segments and will provide an interface that will allow them to be
plugged, while enforcing the same overall behavior of the whole system regardless of the
model used.
The architecture does not describes any interfaces to “service” gateways that will enable non-
UPnP entities to interact with the UPnP devices, services and control points physically
attached to the home network.
1.1 Notation
• In this document, features are described as Required, Recommended, or Optional as
follows:
The key words “MUST,” “MUST NOT,” “REQUIRED,” “SHALL,” “SHALL NOT,” “SHOULD,”
“SHOULD NOT,” “RECOMMENDED,” “MAY,” and “OPTIONAL” in this specification are to
be interpreted as described in [RFC 2119].
In addition, the following keywords are used in this specification:
PROHIBITED – The definition or behavior is an absolute prohibition of this specification.
Opposite of REQUIRED.
CONDITIONALLY REQUIRED – The definition or behavior depends on a condition. If the
specified condition is met, then the definition or behavior is REQUIRED, otherwise it is
PROHIBITED.
CONDITIONALLY OPTIONAL – The definition or behavior depends on a condition. If the
specified condition is met, then the definition or behavior is OPTIONAL, otherwise it is
PROHIBITED.
These keywords are thus capitalized when used to unambiguously specify requirements
over protocol and application features and behavior that affect the interoperability and
security of implementations. When these words are not capitalized, they are meant in
their natural-language sense.
• Strings that are to be taken literally are enclosed in “double quotes”.
• Words that are emphasized are printed in italic.
• Keywords that are defined by the UPnP Working Committee are printed using the forum
character style.
• Keywords that are defined by the UPnP Device Architecture are printed using the arch
character style.
• A double colon delimiter, “::”, signifies a hierarchical parent-child (parent::child)
relationship between the two objects separated by the double colon. This delimiter is used
in multiple contexts, for example: Service::Action(), Action()::Argument,
parentProperty::childProperty.

XXX: © IEC:2010 4 29341-18-1 © ISO/IEC:2011(E)
1.2 References
1.2.1 Informative References
This clause lists the informative references that are provided as information in helping
understand this specification:
[DEVICE] – UPnP Device Architecture, version 1.0. Available at:
http://www.upnp.org/specs/arch/UPnP-arch-DeviceArchitecture-v1.0-20080424.pdf. Latest
version available at: http://www.upnp.org/specs/arch/UPnP-arch-DeviceArchitecture-v1.0.pdf.
[DEVICE-IPv6] – UPnP Device Architecture, version 1.0., Annex A – IP Version 6 Support.
Available at: http://www.upnp.org/resources/documents/AnnexA-IPv6_000.pdf
[ICC] – InboundConnectionConfig:1, UPnP Forum, Available at:
http://www.upnp.org/specs/ra/UPnP-ra-InboundConnectionConfig-v1-Service-20090930.pdf.
Latest version available at: http://www.upnp.org/specs/ra/UPnP-ra-InboundConnectionConfig-
v1-Service.pdf.
[RAClient] – RAClient:1, UPnP Forum,  Available at: http://www.upnp.org/specs/ra/UPnP-ra-
RAClient-v1-Device-20090930.pdf. Latest version available at:
http://www.upnp.org/specs/ra/UPnP-ra-RAClient-v1-Device.pdf.
[RADAConfig] – RADAConfig:1, UPnP Forum,  Available at:
http://www.upnp.org/specs/ra/UPnP-ra-RADAConfig-v1-Service-20090930.pdf. Latest
version available at: http://www.upnp.org/specs/ra/UPnP-ra-RADAConfig-v1-Service.pdf.
[RADASync] – RADASync:1, UPnP Forum, Available at: http://www.upnp.org/specs/ra/UPnP-
ra-RADASync-v1-Service-20090930.pdf. Latest version available at:
http://www.upnp.org/specs/ra/UPnP-ra-RADASync-v1-Service.pdf.
[RADiscoveryAgent] – RADiscoveryAgent:1, UPnP Forum,  Available at:
http://www.upnp.org/specs/ra/UPnP-ra-RADiscoveryAgent-v1-Device-20090930.pdf. Latest
version available at: http://www.upnp.org/specs/ra/UPnP-ra-RADiscoveryAgent-v1-Device.pdf.
[RAServer] – RAServer:1, UPnP Forum,  Available at: http://www.upnp.org/specs/ra/UPnP-
ra-RAServer-v1-Device-20090930.pdf. Latest version available at:
http://www.upnp.org/specs/ra/UPnP-ra-RAServer-v1-Device.pdf.
[RATAConfig] – RATAConfig:1, UPnP Forum,  Available at:
http://www.upnp.org/specs/ra/UPnP-ra-RATAConfig-v1-Service-20090930.pdf. Latest version
available at: http://www.upnp.org/specs/ra/UPnP-ra-RATAConfig-v1-Service.pdf.
[IGD] – InternetGatewayDevice:1, UPnP Forum, November, 2001 Available at:
http://www.upnp.org/standardizeddcps/documents/UPnP_IGD_1.0.zip.
[RFC 1889] – IETF RFC 1889, RTP: A Transport Protocol for Real-Time Applications, H.
Schulzrinne, S. Casner, R. Frederick, V. Jacobson, January 1996. Available at:
http://www.ietf.org/rfc/rfc1889.txt.
[RFC 1918] – IETF RFC 1918, Address Allocation for Private Internets, Y. Rekhter, et. Al,
February 1996 Available at: http://www.ietf.org/rfc/rfc1918.txt
[RFC 2119] – IETF RFC 2119, Key words for use in RFCs to Indicate Requirement Levels, S.
Bradner, March 1997. Available at: http://www.ietf.org/rfcs/rfc2119.txt.
[RFC 2131] – IETF RFC 2131, Dynamic Host Configuration Protocol, R. Droms, March 1997
Available at: http://www.ietf.org/rfc/rfc2131.txt

29341-18-1 XXX: © IEC:2010 © ISO/IEC:2011(E) 5
[RFC 2516] – IETF RFC 2516, A Method for Transmitting PPP Over Ethernet (PPPoE), L.
Mamakos, et. Al, February 1999 Available at: http://www.ietf.org/rfc/rfc2516.txt
[RFC 3056] – IETF RFC 3056, Connection of IPv6 Domains via IPv4 Clouds, B. Carpenter, K.
Moore, February 2001 Available at: http://www.ietf.org/rfc/rfc3056.txt
[RFC 3489] – IETF RFC 3489, STUN - Simple Traversal of User Datagram Protocol (UDP)
Through Network Address Translators (NATs), J. Rosenberg, et. Al, March 2003 Available at:
http://www.ietf.org/rfc/rfc3489.txt
[RFC 3550] – IETF RFC 3550, RTP: A Transport Protocol for Real-Time Applications, H.
Shulzrinne, et. Al, July 2003 Available at: http://www.ietf.org/rfc/rfc3550.txt
[RFC 4380] – IETF RFC 4380, Teredo: Tunneling IPv6 over UDP through Network Address
Translations (NATs), C. Huitema, February 2006 Available at:
http://www.ietf.org/rfc/rfc4380.txt
[RFC 3986] – IETF RFC 3986, Uniform Resource Identifier (URI): Generic Syntax, Tim
Berners-Lee, et. Al, January 2005. Available at: http://www.ietf.org/rfc/rfc3986.txt
1.3 Terms and Abbreviations
1.3.1 Abbreviations
Table 1-1 — Abbreviations
Definition Description
DHCP Dynamic Host Configuration Protocol
DNS Domain Name System
FQDN Fully Qualified Domain Name
ICC Inbound Connection Config
IGD Internet Gateway Device
IPsec IP Security
NAT Network Address Translation
RAC Remote Access Client
RADA Remote Access Discovery Agent
RAS Remote Access Server
RATA Remote Access Transport Agent
STUN Simple Traversal of UDP Through NATs
TLS Transport Layer Security
1.3.2 Terms
1.3.2.1 Credentials
The term credentials refer to certificates, shared secrets or other means of authentication
used in the RATA context.
1.3.2.2 IPv6 Support in Transport Agents
A Transport Agent is said to have IPv6 support if it allows the local and remote devices to
interact according to the UPnP Device Architecture over IPv6 [DEVICE-IPv6].

XXX: © IEC:2010 6 29341-18-1 © ISO/IEC:2011(E)
1.3.2.3 Local Device
A local device is a UPnP device that is attached to the physical network where the RADA is
located.
1.3.2.4 Management Console
The collection of control points that are used to setup, manage and monitor the operations
related to Remote Access.
1.3.2.5 RADAListener
The RADAListener is a logical support function of RADA and incorporates control point and
device functionality for facilitating the SSDP offloading:
a) The RADAListener establishes the initial state of its local network by performing an M-
SEARCH to detect all devices on the local network and notifies the RADA of those
devices.
b) The RADAListener monitors the local SSDP traffic and notifies the RADA when devices
are joining and leaving the UPnP network as described in the UPnP Device Architecture.
1.3.2.6 RADARelay
The RADARelay is a logical support function of RADA and incorporates control point and
device functionality for facilitating the SSDP offloading:
a) For each device in the remote synchronization tree of the RADA, the RADARelay will
send periodic SSDP announcements (e.g. ssdp:alive) onto the local network according
the UPnP Device Architecture.
b) Whenever a device is removed from the remote synchronization tree, the RADARelay will
send an SSDP expiration (e.g. ssdp:byebye) onto the local network according the UPnP
Device Architecture.
c) Whenever a RADARelay receives an SSDP Search request (e.g. ssdp M-SEARCH) for a
device or service that is contained in the remote synchronization tree, it will answer the
search request on behalf of the device in the remote synchronization tree according the
UPnP Device Architecture.
d) When the remote connection is broken, the RADARelay will send an SSDP expiration (i.e.
ssdp:byebye) on the local network for each remote device.
1.3.2.7 Remote Access Client
The Remote Access Client (RAC) is the peer physical device that is not part of the physical
home network. The RAC is exposing only the UPnP devices and services that are embedded
in the physical device.
1.3.2.8 Remote Access Network Interface
The RA network interface is the network interface that is created by the Remote Access
Transport Agent. The settings for this interface are contained in a RATA profile.
1.3.2.9 Remote Access Server
The Remote Access Server (RAS) is the peer physical device located in the home network.
RAS is exposing to the RAC the UPnP devices and services available in the physical home
network as well as any embedded in the physical RAS device. The Remote Access Server
rd
can be the residential router, a personal computer or any 3 party dedicated device.

29341-18-1 XXX: © IEC:2010 © ISO/IEC:2011(E) 7
1.3.2.10 Remote Access Transport Agent Profile
A RATA profile is a configured RATA connection ready to be used by either accepting
connections on the RAS side or to initiate connections on the RAC side.
1.3.2.11 Remote Device
A remote device is a UPnP device that is not attached to the physical network where the
RADA is located.
2 Introduction
UPnP technology was envisioned to be deployed in local area networks. This initial design
goal leads to some decisions which will pose some challenges when trying to expand the
original scope of the UPnP technology beyond the physical boundaries of local area networks
such as those found at home. For example, the discovery step described in UPnP Device
Architecture v1.0 involves multicast messages that will be difficult to forward them beyond the
home network due to the fact that a typical internet router will discard such messages.
Remote Access to UPnP Networks enables a remote UPnP Device or UPnP Control Point to
connect to the home network and interact with the UPnP entities physically attached to the
home network. During this process it is expected that the remote user will experience the
remote device behaving in a similar way as in the home network. In practice, the overall user
experience will be degraded due to the limitations induced by external factors, such as
network latencies and bandwidth, but nevertheless the remote device will have to go to the
same steps (e.g. IP addressing, discovery, description, control, eventing) as any UPnP
device present in a home network.

Figure 2-1 — UPnP Remote Access.
Remote Access architecture undertakes the provisions needed in order to minimize the
adverse effects of the internal and external factors and bring the remote user experience as
close as possible to the one available in the local area network.
3 Operational Considerations
3.1 Remote Access Environment
A typical Remote Access network scenario is depicted in Figure 3-1, where we have a remote
UPnP entity that connects to the home UPnP network in order to interact with the home UPnP
entities. The remote UPnP entity connects to the internet via an access network and
establishes a remote access connection to the home network via public internet backbone to
the Remote Access server that has access to the internet via the ISP network. There are
cases when, due to various reasons, the remote UPnP entity cannot establish remote access
connection by itself and it needs the help of some
...