Note: Descriptions are shown in the official language in which they were submitted.
CA 02610168 2007-11-29
WO 2006/128491 PCT/EP2005/011543
METHOD FOR TRANSMITTING INFORMATION IN A MULTICAST ENVIRONMENT
FIELD OF THE INVENTION
The present invention relates to a method for transmitting information to an
individual
end-user device in a multicast environment.
BACKGROUND OF THE INVENTION
Via broadband networks multi-media services are increasingly provided to
customers.
Examples of multi-media services are triple-play services whereby voice,
Internet/data
and video related services are provided. Often, triple-play service
provisioning takes
place in a multicast environment. Multicast is communication between a single
sender
and multiple receivers on a network. Typical use include the distribution of
video such
as video on demand. Standards are being developed to support multicasting over
a
TCP/IP network (such as the Internet). An example of such a standard is IP
Multicast.
In relation to multicast environments the problem of transmitting single
messages to an
individual receiver has been identified. This can be relevant in an
architecture wherein
a residential gateway at the customer's location is used for the interfacing
between the
end-user devices and the broadband network. Usually private IP-addresses have
been
assigned to the end-user devices, i.e. an end-user device can be addressed by
means
of its private IP-address by other end-user device comprised by the private
domain.
However, private IP-addresses are not defined in the public domain, i.e. it is
not
possible from a device in the public domain to address a specific end-user
device as a
destination device by means of a private IP-address. This is because only
public IP-
addresses are defined in the public domain. So, although a public IP-address
is
assigned to the residential gateway, the end-user devices behind the
residential
gateway cannot be addressed individually because the private IP-addresses of
the
end-user devices are not known in the public domain. A known solution for this
problem is the mechanism of port forwarding in the residential gateway.
However, a
drawback of this known solution is that additional configuration steps in
relation to the
residential gateway are required. According to another known solution a
dedicated
CA 02610168 2007-11-29
WO 2006/128491 PCT/EP2005/011543
2
channel can de defined between the sender and a receiving end-user device.
However,
the amount of simultaneously active channels can then be considerably high.
AIM OF THE INVENTION
It is an object of the invention to eliminate the drawbacks of the prior art
and to provide
a method for transmitting information to an individual end-user device in a
multicast
environment.
SUMMARY OF THE INVENTION
It is disclosed that in a multicast network environment individual information
can be
transmitted via a barker channel between a server and an individual end-user
device.
In the case of digital television services the present invention enables,
inter alia,
individual information that is addressed to a specific customer to appear on
the
television screen. This is accomplished by transmitting the individual
information via the
barker channel from a server to the set-top box via which the television is
connected to
the access infrastructure. It is also disclosed that an identification number
can be
added to the individual information. In relation to digital television
services, the present
invention makes use of the insight that set-top boxes already are provided
with a
unique code. As a result of this, the adding to the individual information of
an
identification number that is related to the unique code of a specific set-top
box enables
to individually address set-top boxes.
In a first aspect of the invention is disclosed that in a multicast network
environment
individual information can be transmitted via a barker channel to an
individual end-user
device. The present invention does not only apply to multicast environments;
also
broadcast environments or combined multicast/broadcast environments are within
the
scope of this invention. In the prior art a barker channel can be used for
transmitting
generic information to end-user devices. According to the invention it is
identified that in
a customer environment comprising several end-user devices private (i.e. non-
public)
IP addresses are used for the identification of the end-user devices. In IP
related
network environments this is a problem since it is not possible then to
address from the
CA 02610168 2007-11-29
WO 2006/128491 PCT/EP2005/011543
3
public domain one specific end-user device. The scope of this invention is not
limited to
IP related networks; also other types of networks wherein private addressing
is applied
are considered.
The end-user devices referred to above can be part of a home network of a
customer,
although corporate local network environments are not excluded in this
invention.
Typically there is a broadband network to which customer network environments
and
corporate network environments are connected by means of an access network.
Several communication services may be provided via such an infrastructure, for
instance data services, Internet, voice and digital video services (Triple
Play). Often in
such a context the IP protocol is used combined with other communication
protocols
such as FTTH (fiber to the home), ADSL (asymmetric digital subscriber line) or
VDSL
(very high speed digital subscriber line). An end-user device can for example
be a
personal computer system, a television set, a set-top box or a telephone.
However, an
end-user device can also be any other type of device that resides at the
customer
premise such as a residential gateway, a DSL modem or a set-top box.
The access infrastructure may be comprised of copper, fiber or wireless
components
(or a combination of these). For example, in the case of an ADSL access
infrastructure
the communication path between a customer premise and a public telephone
exchange is partly comprised of fiber, i.e. between the public telephone
exchange and
the DSLAM there is fiber, while between the DSLAM and the customer premise
there is
copper wire. It is also possible that the access infrastructure is a mobile
infrastructure
enabling mobile end-user devices (such as 3G and 4G handsets) to connect to a
network.
In the case of digital television services the present invention enables,
inter alia,
individual information addressed to a specific customer to appear on the
television
screen. This is accomplished by transmitting this individual information via
the barker
channel from a server to the set-top box via which the television is connected
to the
access infrastructure. Individual information in this context can for instance
be data that
appears on the television screen indicating that the customer has received a
phone
call. In the prior art it is generic information (information that is
accessible to multiple
users) and not individual information that can be transmitted via the barker
channel.
The present invention also is applicable in relation to other types of end-
user devices
such as (personal) computer devices, gameboxes, 3G handsets, PDA's and IP
CA 02610168 2007-11-29
WO 2006/128491 PCT/EP2005/011543
4
telephones. For instance, according to the present invention it may be
possible to
transmit individual information such as a software update to a personal
computer.
According to another aspect of the invention there can be added an
identification
number to the individual information that is to be transmitted via the
barkerchannel. In
relation to digital television services, the present invention makes use of
the insight that
set-top boxes already are provided with a unique code. As a result of this,
adding to the
individual information of an identification number that is related to the
unique code of a
specific set-top box enables that specific set-top box to be addressed.
According to yet another aspect of the present invention an end-user device
may be
equipped (for instance by means of software measures) to detect the
identification
number that is added to individual information. In the case that the
identification
number equals (or is related to) the unique code of the end-user device, the
end-user
device will process the individual information. If, however, the
identification number
does not equal (or relate) to the unique code of a set-top box, then that
settop box
won't process the individual information.
CA 02610168 2007-11-29
WO 2006/128491 PCT/EP2005/011543
BRIEF DESCRIPTION OF THE DRAWING FIGURE
5 The foregoing aspects and many of the attendant advantages of this invention
will be
explained by reference to the following detailed description, when taken in
conjunction
with the accompanying drawing, wherein:
FIG. 1 is a block diagram illustrating an architecture whereby a customer
environment
(8) is connected to a broadband network (1).
FIG. 2 is a block diagram in which the concept of transmitting individual
information to
an end-user device in a multicast environment is depicted.
EXEMPLARY EMBODIMENTS
For the purpose of teaching of the invention, preferred embodiments of the
method and
devices of the invention are described in the sequel. It will be apparent to
the person
skilled in the art that other alternative and equivalent embodiments of the
invention can
be conceived and reduced to practice without departing form the true spirit of
the
invention, the scope of the invention being limited only by the appended
claims as
finally granted.
FIG. I shows a network (1), such as a broadband network, via which services
such as
triple play services can be provided to customers. The network (1) can be
based on
any type of communication technology such as FTTH (fiber to the home), ADSL,
VDSL,
MPLS, or mobile communication protocols. For the provisioning of such
services, a
server (2) is connected to the network (1). The server (2) can for
instancehost a video
server, although it is also possible that more than one media applications are
hosted by
server (2). There may also be more than one server (2) connected to the
network (1)
each covering a specific media service. In this embodiment the architecture is
based
on the IP protocol although this is not a limitation in relation to the
present invention. In
the architecture according to FIG. I there is a DSLAM (9) (Digital Subscriber
Line
Access Multiplexer) that is connected to the network (1) and to a customer
environment
CA 02610168 2007-11-29
WO 2006/128491 PCT/EP2005/011543
6
(8). The DSLAM (9) is in general part of an access infrastructure and may be
operated
by the same party that operates the network (1). Implementations of the access
infrastructure between the customer environment (8) and the network (1) may be
different, dependent on the technology (ADSL, VDSL, etc.) to be supported.
The DSLAM (9) takes connections from many customers and aggregates them onto a
single, high-capacity connection to the network (1). A DSLAM (9) is generally
flexible
and able to support multiple types of DSL (Digital Subscriber Line) in a
single central
office, and different varieties of protocol and modulation. For example,
different
customer environments (8) may be connected via a copper wire (xDSL) to the
DSLAM
(9). The DSLAM (9) may for instance support ADSL whereby the DSLAM (9) is
connected to the network (1) via a fiber infrastructure. The customer
environment (8)
can be connected to the DSLAM (9) by means of for instance a residential
gateway (3)
The residential gateway (3) is network device located at the customer premise
that
interfaces between the home network (comprising end-user devices) and the
public
access network (comprising e.g. the DSLAM (9)). The residential gateway (3)
may also
be able to connect the end-user devices that reside at the customer location
(8). End-
user devices may for instance be a personal computer (4) via which data or
Internet
services may be provided, a television (6) that is connected to the
residential gateway
(3) via a set-top box (STB) (5) for the provisioning of digital and/or
interactive television,
and an IP telephone (7) for the provisioning of IP telephony. The provisioning
of this
combination of services is often called triple play.
For digital interactive television there is often a broadcast based
architecture in relation
to the network (1). For example, there may be 50 television channels and 100
radio
channels broadcasted from the video server (which is hosted by serve- (2)) to
the
DSLAM's (9). Between the customer environment (8) and a DSLAM (9), however,
there
might be used a multicast mechanism instead of a broadcast mechanism. When a
set-
top box (5) has registered to a particular channel (one of the set of 100
television
channels) this channel will be routed by the DSLAM (9) to the residential
gateway to
which the STB (5) is connected. Registration in a multicast environment can
for
instance be accomplished using the Internet Group Management Protocol (IGMP).
Via a barker channel (12) that is defined between the server (2) and the STB
(5)
additional information can be provided to the customer. This additional
information can
for instance be background information relating the television program that is
watched
CA 02610168 2007-11-29
WO 2006/128491 PCT/EP2005/011543
7
by the customer or any type of promotional information. The customer can
request for
the additional information but in general the same information is being
broadcasted to
all the customers and each customer may choose whether or not to receive the
information. The barker channel (12) will provide data and system information
on all
content and services being broadcasted. The client derives a menu of services
available on the network from the barker channel (12). Client software in the
STB (5)
will use the barker channel (12) to capture material regardless of the channel
in which it
appears. In addition to the barker channel (12), the client software will
filter and capture
or display content based on metadata tags attached to the content.
FIG. 2 shows a number of aspects that are part of amethod according to the
present
invention for an architecture similar to that of FIG. 1. This method enables
individual
information (10) to be transmitted to an individual STB (5), i.e. information
that is
intended for a specific customer. This in contrary to the additional
information that
normally can be received by a STB (5) via a barker channel. According to an
aspect of
the invention individual information (10) is sent by the server (2) via the
barker channel
(12). In a best mode embodiment, the server (2) can add for addressing
purposes an
identification number (11) to the individual information (10). In general
STB's already
have a unique code that can be a reference for the identification code (11),
i.e. the
unique code can be used to address a set-top box (5). In an implementation it
is for
instance possible to add the unique code of the addressed STB (5) in the
header field
of a data packet. When a DSLAM (9) has received the individual information
(10) and
the corresponding identification number (11), both will be routed to every STB
(5) that
has registered to the barker channel (12) at an earlier stage. However, only
the STB (5)
with a unique code that corresponds to the identification number (11) will
process the
individual information (10). For this purpose an STB (5) needs to be upgraded
in order
to be able to handle incoming individual information (10) and a corresponding
identification number (11). This upgrading is however a small software
modification
since STB's (5) in general already comprise mechanisms in which encryption
keys are
used for accessing information sent to the STB (5).
In another embodiment it may also be possible that the individual information
(10)
comprises an announcement to a specific customer or end-user device informing
that
customer or end-user device that, for instance, a message is available at
server (2).
After having received this announcement the customer or end-user device is
able to
retrieve the message from server (2). The way for retrieving the message can
be
CA 02610168 2007-11-29
WO 2006/128491 PCT/EP2005/011543
8
according to any type of communication scheme or protocol. Not only messages
can
be retrieved but also any other type of information such as software updates,
files and
multi-media applications.
