Vitor Pinto, Vitor Ribeiro
Portugal Telecom Inovação, Rua Eng. José Ferreira Pinto Basto, 3810-106 Aveiro, Portugal
Iván Vidal, Jaime García, Francisco Valera, Arturo Azcorra
Universidad Carlos III de Madrid, Avda. de la Universidad 30, 28911 Leganés, Madrid, Spain
Keywords: Multimedia, Residential Gateway, e-Care, TISPAN-NGN, QoS, OSGi, Triple Play, Multi Play, Broadband
Abstract: Internet access has been, until now, the main driver for the generalization of broadband connections in the
residential market. Simple IP based services like email and web browsing were, during many years, the
typical services provided to residential customers. Today the telecommunications market is changing and
operators are looking for ways to provide, through those same IP broadband connections, value added
services. These will, in one hand, increase their revenues and on the other hand, provide to the customer a
wider range of services until now inaccessible. Triple Play is already a reality, although, the convergence
between mobile and fixed networks is bringing to the home a new range of IP Multimedia Subsystem (IMS)
based services, which used to be exclusive of the mobile world. Although, to successfully achieve the
delivery of these new services, the interface between residential and operator’s networks must be
meticulously defined and implemented, by what is usually called the residential gateway (RGW). This paper
focuses on emerging residential services and the implications that these impose on the RGW. The
coexistence between IMS based services and non-IMS based services are also approached on this paper,
with a special emphasis on RGW Quality of Service (QoS) issues.
During the last few years the amount of bandwidth
offered by the telecommunication operators to the
residential customers has increased at an incredible
fast pace. If previous residential services were
limited to little more than email and web browsing,
the increase on the available bandwidth pushed the
appearance of bandwidth hungry services like peer-
to-peer file sharing or on-line gaming. Although
these are important services to the user, they do not
bring any additional revenue to operators. For this
reason operators are now looking for ways to
distribute added value services, like multicast IPTV,
Video on Demand (VoD), Voice over IP (VoIP),
among others, to their customers using an enhanced
broadband access network. In this context, the
European research project MUSE - "Multi Service
Access Everywhere” (MUSE, 2004-2007) was
created with the overall objective of researching and
developing a future low-cost, multi-service, multi-
provider access/edge network which allows to the
European citizens access to this whole new range of
multimedia services. The first phase of the project,
which ran from January 2004 to December 2005,
was mainly concerned with the definition of a
network architecture that allows the distribution of
advanced multimedia services to residential
customers. For the second phase of the project,
running from January 2006 to December 2007, it has
aimed the convergence of this broadband network
with mobile networks, which will result in the
combination of both architectures in a single
architectural model. This network level convergence
will be translated in the end, on convergence of
services, which means that services usually on the
domain of mobile networks will be available to
residential customers through this converged
Pinto V., Ribeiro V., Vidal I., García J., Valera F. and Azcorra A. (2007).
In Proceedings of the Second International Conference on Signal Processing and Multimedia Applications, pages 375-378
DOI: 10.5220/0002139003750378
On the other hand, nowadays, many initiatives
are being proposed on Next Generation Networks
(NGN), trying to cover the convergence between the
fixed and the mobile world. In this respect, TISPAN
group from ETSI is working on the specification of
an IMS based NGN. As a result of this ongoing
work, the first release of standards for TISPAN
NGN (TISPAN, 2006) was published at the
beginning of 2006. Nevertheless, in this release there
are several identified open issues, being one of them
related with QoS provisioning in the residential
environment. In TISPAN NGN release 1 the QoS
solution is only provided for the access network, but
the real QoS perceived by the end user is end to end.
In this respect, the work that is being performed
within the MUSE project concerning the residential
environment may be used in order to extend the
TISPAN QoS solution to the end user network.
One of the most relevant entities of MUSE
network architecture is the Residential Gateway
(RGW), which is placed at the edge of the access
network. Since the home network environment is
quite particular and different from the access
network environment, this device is responsible for
making all the necessary translations between
functionalities implemented on both networks,
making them totally inter operable and functional.
These functionalities are even more complex when
value added services are provided and convergence
between mobile and fixed services is wanted.
This article describes some of the key aspects
and functionalities that the RGW must support
considering the described scenario.
MUSE access network allows the distribution of
multiple services using the Ethernet/IP technology,
although, in the home environment services are
sometimes terminated on end devices that do not
support this kind of technology (e.g. TVs, POTS
telephone handsets, simple medical appliances, etc.).
Therefore, a function that performs the adaptation of
service data encapsulated in Ethernet/IP to a format
that is reproducible in those end devices is required
in the home network for every specific service. In a
broader way, this functionality is implemented by
devices that are usually referred as service gateways.
Examples of service gateways are the Set Top Boxes
for an IPTV video service or an Analogue Terminal
Adapter for a VoIP service terminated on a POTS
handset. In a Triple Play scenario, usually, each
service has its own dedicated service gateway.
Although, as the number of services increases a
number of advantages arises if a single device acts
as a service gateway for different services, namely:
Possibility of interaction between services,
allowing the generation of new services,
which is in line with a Multi Play scenario.
As the number of residential services increases,
the configuration and management of services
will be easier if these are centralized in a
single device.
The same approach can be used for all services
running on the service gateway regarding
access, control and personalization of services
by the user.
The cost of the hardware platform that supports
the service gateway can be shared between the
different service providers that use it to deploy
their services.
Considering that the RGW is directly facing the
broadband access network and has several interfaces
to home network devices (where services are
typically terminated) and that all services data must
pass through the RGW, the RGW is, therefore, an
optimum point for the deployment of this common
service gateway. In MUSE RGW, an
implementation of the OSGi Service Platform
(OSGi, 2003) is executed, so the RGW can also act
as a service gateway, which can support a variety of
value added services. Advantages of using the OSGi
platform include, among others, hardware
independence, possibility of remotely install/remove
services, remote management of the life cycle of
services, remote configuration of services and the
possibility of having different services interacting, as
it is assumed in a Multi-Play scenario.
Taking advantage of MUSE multi service RGW, a
remote medical monitoring service has been
implemented as a set of OSGi bundles (software
modules in OSGi terminology). This service allows
a patient to be at home and through simple medical
equipment submit, automatically and periodically,
sets of medical measures to a hospital remote
medical database. There, they can be analyzed,
checked for alarm conditions, etc. Since all the setup
and installation of the service can be quite
complicated for a residential user, apart from the
physical connection of the medical equipment to the
RGW, all the tasks must be remotely and if possible
SIGMAP 2007 - International Conference on Signal Processing and Multimedia Applications
automatically performed by the service provider.
Figure 1 presents the entities that intervene in the
Figure 1: Remote medical monitoring service entities.
The first action is the subscription of the service
by the customer, which can be done in several ways.
One way, is through a web page, where the customer
can access and subscribe the service (Figure 1, step
1). This action triggers the automatic transfer of a
bundle (that implements part of the service) from a
bundle repository to the RGW, as well as its
installation and activation (Figure 1, step 2). When
the user connects the medical equipment to the
RGW (Figure 1, step 3), a process of drivers
selection occurs and ends with the automatic
transfer, installation and activation of a new set of
bundles that allows the communication between the
OSGi platform and the medical equipment (Figure 1,
step 4). This last set of bundles is used by the first
installed bundle and together they implement the
remote medical monitoring service. For this moment
on, measures taken to the patient by the device are
periodically submitted to the remote medical
database (Figure 1, step 5). When the service is no
longer needed, the customer can access the same
web page as before and unsubscribe the service. This
action triggers the automatic removal of the service
from the RGW (i.e. of the bundles that together
assemble the service).
As this service demonstrates, MUSE RGW
implements a service gateway that is remotely
manageable and is able to support the automatic
installation and removal of networked services,
without any input of the user regarding configuration
or management of those same services.
In order to achieve the aforementioned
functionalities and to support the e-care service (or
any other added value service), the RGW must be
prepared to provide a certain degree of performance
per traffic flow. In other words, every packet
traversing the RGW (upstream or downstream
direction) must be properly treated using the
configuration parameters installed (manually or
automatically). With this mechanism, some packets
with higher priorities will be forwarded before the
lower ones. With these ideas in mind, the RGW has
been developed to provide two functionalities
regarding the QoS:
1. Configure the QoS. An end-user or an
administrator must configure the QoS
parameters in the RGW in advance. It is also
possible to configure the RGW using other
kind of methods (for example, using the SIP
information during a session establishment).
This stage could be dynamic and the
parameters could be changed during the
normal operation.
2. QoS treatment. The RGW will forward packets
as configured in the previous step.
The RGW architecture is well documented in
(Vidal, 2006) where it is explained that the RGW is
divided in two levels: the data and application level.
The data level is where the packets flow and where
the QoS is performed. The application level is used
to configure all available RGW parameters and the
QoS is one of them. The SIP method used to
configure the QoS is a bit different because those
packets are extracted from the data level and
forwarded to a special application called SIP SP
(SIP Signalling Processor). This SP uses the
information transported in the packet to infer the
QoS parameters for the next data packet flow.
An important functionality added to the RGW
architecture is the Call Admission Control (CAC)
mechanism introduced in (Vidal, 2007). With this
mechanism enabled, the RGW guarantees that all
flows will be handled as they are configured.
Whenever there is a request for a new flow insertion,
the CAC should evaluate whether it can be accepted
or not. If it is possible, the CAC must refresh the
available resources decreasing the previous ones
with the new accepted.
The CAC mechanism was defined to easily
introduce the RGW into the TISPAN NGN
architecture because it can be inserted as is (the
RGW performs a local CAC) or extended to provide
an external interface where the core IMS can
remotely configure it.
As some applications need to configure a flow
even when the resources are exhausted (for example,
for emergency calls or for the above mentioned
remote medical monitoring service) the CAC
mechanism could be deactivated using an
unavoidable rule”.
Figure 2: Testbed for the QoS trials.
This article presents a RGW prototype that has been
developed and trialled in a broadband access
scenario, such as the one specified in MUSE project.
The presented RGW is not only able to support the
three types of multimedia services that usually figure
in a Triple Play scenario, but also more advanced
services such as the ones considered in multi play
scenarios. In order to achieve this, the presented
RGW implements a multi service gateway which
takes advantage of the central position that the RGW
occupies in the home network. This multi service
gateway permits the dynamic deployment of
advanced added value services, such as the remote
medical monitoring service described in this article.
Moreover, the service gateway allows the remote
installation, activation and configuration of such
advanced services, without requiring any action
from the user for the services configuration and
Although, in such a multi service environment,
the convergence of multiple services (i.e. of the data
flows belonging to those multiple services) through
a single device, imposes several challenges to the
RGW, namely at a QoS level. So, the presented
prototype is also able to handle the different data
flows belonging to distinct services according to
different policies (Valera, 2006). Two methods are
implemented in the RGW that permit the
configuration of such policies. The first one is based
on pre configured rules and the second one operates
in a dynamic way, using information exchanged
through signalling protocols (e.g. SIP). This last
method together with a carefully designed CAC
function implemented on the RGW, allows an easy
integration of the prototype into the TISPAN NGN
architecture. Therefore, besides the above mentioned
services, our RGW is also suitable to operate in
fixed mobile convergence scenarios, where
residential customers can take advantage of
multimedia services that used to be exclusive of the
mobile world.
This article has been partially granted by the
European Commission through the MUSE (IST-
026442) project.
MUSE, “Multi User Access Everywhere”. European
Union 6th Framework Programme for Research and
Technological Development. URL: http://www.ist-
muse.org, 2004-2007
TISPAN, “ETSI TR 180 001 V1.1.1:
Telecommunications and Internet converged Services
and Protocols for Advanced Networking (TISPAN);
NGN Release 1; Release definition.”, March 2006.
OSGi Alliance. OSGi Service Platform, the OSGi
Alliance. IOS Press. Amsterdam, 1
edition. 2003.
Vidal, I.; García, J.; Valera, F.; Soto, I.; Azcorra, A.
Adaptive Quality of Service Management for Next
Generation Residential Gateways” 9th IFIP/IEEE
International Conference on Management of
Multimedia Networks and Services, MMNS 2006.
October 2006. Dublin, Ireland.
Vidal, I.; García, J.; Valera, F.; Soto, I.; Azcorra, A.
Integration of a QoS aware end user network within
the TISPAN NGN solutions” IEEE 4th European
Conference on Universal Multiservice Networks
(ECUMN'2007). ISBN 978-0-7695-2768-0, pp. 152-
160, February 2007. Toulouse. France
F. Valera, J. García, C. Guerrero, Vitor Pinto and Vitor
Ribeiro. “Demo of Triple Play Services with QoS in a
Broadband Access Residential Gateway”, IEEE
Infocom, Barcelona (Spain) 2006. April 2006.
Barcelona, Spain.
SIGMAP 2007 - International Conference on Signal Processing and Multimedia Applications