Note: Descriptions are shown in the official language in which they were submitted.
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Method for transferrina information
FIELD OF THE INVENTION
The present invention relates generally to a method of
information transfer, for example an electronic map,
multimedia applications or the like, with one or more
radiofrequency receivers such as mobile, portable, and
stationary radiofrequency receivers, especially to a single
predetermined digital video broadcasting (DVB) receiver.
BACKGROUND TO THE INVENTION
There exists a number of different methods of transferring
information from an information/content provider to an
information consumer, i.e. to the destination where the
information/content is intended to be used. In order to
transfer information to an information consumer there must
be some means for localizing the information consumer,
which in some circumstances can be a problem. If the
information consumer is stationary then the problem might
arise the first time an information transfer is to take
place. On the other hand if the information consumer is
mobile, then, depending on the method of transfer, the
information consumer might have to be localized anew for
each information transfer that is to take place. Another
problem is how to transfer the information in an effective
manner, both from an economic as well as from a time point
of view, the information is perhaps no good tomorrow and it
must be affordable to get it.
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A mobile telephone system is an information transfer
system. Voice information in the form of analog or digital
information and also possibly pure digital data. A mobile
telephone system addresses the previously mentioned
problems in a manner intended to be efficient mainly for
speech. A mobile telephone system, GSM (Global System for
Mobile communication) for example, is a two-way
communications system that uses cells in which transfer of
information between a mobile telephone and a base station
occur. As long as a mobile telephone is powered up (and
even when on-hook) an intermittent exchange of information
between the mobile phone and the base station of a cell in
question takes place. The information exchange that takes
place when the mobile phone is on-hook is, among other
things, used for keeping track of the mobile phone. The
base station in question passes this information on to a
central database that the mobile telephone operator
maintains to keep track of where all the mobile telephones
are located, i.e. in what cell or group of cells they are
for the moment. When a request to establish contact with
a mobile phone is made then an inquiry to the central
database is made to find out in which cell the mobile phone
is located so that the call can be directed to the
appropriate base station for a subsequent correct radio
communication setup. Unfortunately a mobile telephone
system has a relatively narrow bandwidth, i.e. the
information transfer rate capacity is fairly low as its
main purpose is to bidirectionally transfer speech which
does not require a very high transfer rate.
A DVB (Digital Video Broadcasting) system, i.e. a
broadcasting system, can have a similar cell structure as
a mobile telephone system has, but DVB is a one-way
broadcasting system, i.e. there is no way a DVB receiver
can communicate with a DVB transmitter within the DVB
system. The local DVB transmitter does not know which DVB
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receivers are tuned in or which DVB receivers can receive
the transmitter or if any DVB receiver at all can or is
receiving for that matter. A desire to transfer
information to a specific DVB receiver and ensure that the
DVB receiver has a theoretical chance of receiving the
information would therefore involve transmitting this
information across all cells that the DVB receiver might be
located in, which usually means the whole DVB network and
also over all the different frequencies used in the DVB
network. This will result in an extremely poor usage
efficiency of a DVB network even though a DVB system has a
relatively large bandwidth, i.e. the information transfer
rate capacity is very large to be able to serve its main
purpose of broadcasting television to a large number of
recipients. Unfortunately it could be argued that the
described method does not use the DVB broadcasting system
in a very effective manner since system bandwidth in the
whole DVB network is used for the purpose of an information
transfer of information which only has a value in a very
limited area to perhaps a very limited number of receivers .
There seems to be no manner in which to transfer
information in a DVB system to a predetermined single DVB
receiver without having to download the whole system with
the information, and especially not how to transfer this
information in a secure manner.
SUMMARY OF THE INVENTION
An object of the invention is to define a method for
providing an efficient manner of transferring information
via a digital video broadcasting system to one or more
predetermined information consumers.
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Another object of the invention is to define a method which
is able to transfer information in a digital video
broadcasting system in a safe, error tolerant and efficient
manner without using more bandwidth than necessary of the
digital video broadcasting system.
The above-mentioned objects are achieved in accordance with
the invention by a method for transferring information from
an information provider to an information consumer in a
highly efficient manner by means of a digital video
broadcasting (DVB) system and a secondary bidirectional
transfer network. The secondary bidirectional transfer
network provides information of where the DVB receiver of
the information consumer is located so that only suitable
DVB transmitters in the area are used for the information
transfer itself. The location is determined by having for
example a network identification of the transmission stream
that the receiver can receive transferred via the secondary
bidirectional transfer network for identification of the
transmitter or transmitters used. Thereby only the minimum
number of necessary DVB transmitters needs to be used for
the information transfer, thus relieving the rest of the
DVB transmitters from an unnecessary downloading.
The aforementioned objects are also achieved according to
the invention by a method for transferring information from
an information provider to a predetermined information
consumer. The information is transferred by means of a
digital video broadcasting system to a digital video
broadcasting receiver of the predetermined information
consumer. To enable an efficient information transfer when
a demand to transfer information to the predetermined
information consumer is originated by the information
provider the information transfer is supported by a
secondary bidirectional transfer network such as NMT
(Nordic Mobile Telephone), GSM (Global System for Mobile
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communication), PSTN (Public Switched Telephone Network),
Internet, or the like. The method comprises a number of
steps. First the information provider establishes contact
with an information transfer point for requesting transfer
5 of information to the predetermined information consumer.
The information transfer point can be part of the
information provider, part of the DVB system, or a separate
service. Thereafter the information transfer point
retrieves access information of the predetermined
information consumer based on the request from the
information provider. As a third step the information
transfer point establishes an initial contact with the
predetermined information consumer based on the retrieved
access information about the predetermined information
consumer. Thereafter the predetermined information
consumer provides the information transfer point, via the
secondary bidirectional transfer network, with transfer
configuration information comprising, in dependence on the
specific DVB network, at least one of the transport stream
identification, the network identification, the original
network identification, and/or the transmitter frequency
which identifies a transmitter and transport stream that
the digital video broadcasting receiver of the
predetermined information consumer receives or can receive.
Finally the information provider via the information
transfer point, based on the transfer configuration
information, transfers information over the digital video
broadcasting system to the digital video broadcasting
receiver of the predetermined information consumer to
thereby transfer information from the information provider
to the predetermined information consumer in an efficient
way.
Suitably the method advantageously also, based on the
transfer configuration information, has the information
transfer point transfer the information to the digital
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video broadcasting receiver of the predetermined
information consumer over a selected transmitter or
transmitters in the digital video broadcasting system.
The access information of the predetermined information
consumer preferably provides information of how contact can
be made with the predetermined information consumer via the
secondary bidirectional transfer network and that the step
of establishing an initial contact with the predetermined
information consumer is done via the secondary
bidirectional transfer network based on the access
information of the predetermined information consumer. If
the step of establishing initial contact with the
predetermined information consumer via the secondary
bidirectional transfer network cannot be concluded then
preferably a broadcast over the digital video broadcasting
system is performed to alert the predetermined information
consumer to establish contact with the information transfer
point. If the information transfer point after a timeout
has not been able to establish contact with the
predetermined information consumer then preferably the
information provider is notified that the predetermined
information consumer cannot be positively contacted.
The access information of the predetermined information
consumer can alternatively advantageously either provide no
information on how contact can be made with the
predetermined information consumer via the secondary
bidirectional transfer network or provide information of
how the predetermined information consumer is to be
contacted by means of broadcasting over the digital video
broadcasting system to thereby alert the predetermined
information consumer to establish contact with the
information transfer point and that the step of
establishing an initial contact with the predetermined
information consumer is done via a broadcast over the
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digital video broadcasting system to thereby alert the
predetermined information consumer to establish contact
with the information transfer point. If the information
transfer point after a timeout has not been able to
establish contact with the predetermined information
consumer then preferably the information provider is
notified that the predetermined information consumer cannot
be positively contacted.
The transfer configuration information can further
advantageously also comprise at least one of either the
transport stream identification, the network
identification, the original network identification, and/or
the transmitter frequency which identifies the transmitter
and transport stream of all transmitters receivable by the
digital video broadcasting receiver of the predetermined
information consumer, the field strengths of all receivable
transmitters, what program/transport, stream if any the
digital video broadcasting receiver of the predetermined
information consumer is currently receiving, or alternative
information transfer routes. The information transfer
point can, based on the transfer configuration information,
in some embodiments of the invention determine when and
with what transport stream the information transfer is to
take place and by means of the secondary bidirectional
transfer network notify the predetermined information
consumer of when and with what transport stream the
information transfer is to take place. In some other
embodiments the decision for what, if any, alternative
transport stream the information transfer should use can
suitably be made by the information consumer or the digital
video broadcasting receiver of the information consumer.
In some versions/embodiments of the invention increased
security of the information that is to be transferred is of
increased concern and these comprise further steps. In a
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first additional step the information transfer point
transfers a crypto key to the predetermined information
consumer by means of the secondary bidirectional transfer
network before, during or after transferring information
over the digital video broadcasting system. The
information to be transferred is encoded either by the
information provider or by the information transfer point.
Decoding of the transferred information is performed by
means of the transferred crypto key either in the digital
video broadcasting receiver of the predetermined
information consumer or by the predetermined information
consumer. When a high reliability of the transfer of the
information is necessary the method according to the
invention further comprises the following steps. First
transferring checksums or the like, of the information that
has or will be transferred via the digital video
broadcasting system, via the secondary bidirectional
transfer network to the predetermined information consumer.
Secondly checking the transferred information if it is
uncorrupted based on the transferred checksums or the like.
Checking is performed in the digital video broadcasting
receiver of the predetermined information consumer or by
the predetermined information consumer. Thirdly the
digital video broadcasting receiver of the predetermined
information consumer or the predetermined information
consumer makes a request to the information transfer point
of a resending of corrupted transferred information. The
request is made via the secondary bidirectional transfer
network.
The aforementioned objects are also achieved by a method
for transferring information from an information provider
to an information consumer by means of a digital video
broadcasting system to a digital video broadcasting
receiver of the information consumer. The transfer is
executed with support of a secondary bidirectional transfer
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network to thereby enable an efficient information transfer
when a demand to transfer information to the information
consumer is originated by the information consumer. The
method comprises a number of steps. First of all the
information consumer establishes an initial contact with an
information transfer point via the secondary bidirectional
transfer network with a request for an information transfer
from the information provider to the information consumer.
The information transfer point can be part of the
information provider, part of the DVB system, or a separate
service. Then the information consumer provides the
information transfer point, via the secondary bidirectional
transfer network, with transfer configuration information
comprising, in dependence on the specific DVB network, at
least one of the transport stream identification, the
network identification, the original network
identification, and/or the transmitter frequency which
identifies a transmitter and transport stream that the
digital video broadcasting receiver of the predetermined
information consumer receives or can receive. The
information transfer point retrieves the requested
information. Thereafter the information provider via the
information transfer point, based on the transfer
configuration information, transfers information over the
digital video broadcasting system to the digital video
broadcasting receiver of the information consumer to
thereby transfer information from the information provider
to the information consumer in an efficient manner.
The method advantageously also, based on the transfer
configuration information, has the information transfer
point transfer the information to the digital video
broadcasting receiver of the information consumer over a
selected transmitter or transmitters in the digital video
broadcasting system. The transfer configuration
information can further advantageously also comprise at
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least one of either the transport stream identification,
the network identification, the original network
identification, and/or the transmitter frequency which
identifies the transmitter and transport stream of all
5 transmitters receivable by the digital video broadcasting
receiver of the predetermined information consumer, the
field strengths of all receivable transmitters, what
program/transport stream if any the digital video
broadcasting receiver of the predetermined information
10 consumer is currently receiving, or alternative information
transfer routes. The information transfer point based on
the transfer configuration information can in some
embodiments of the invention determine when and with what
channel the information transfer is to take place and by
means of the secondary bidirectional transfer network
notify the information consumer of when and with what
channel the information transfer is to take place.
The information transfer point can preferably confirm the
availability or non-availability of the requested
information to the information consumer via the secondary
bidirectional transfer network or via the digital video
broadcasting system.
In some versions/embodiments of the invention increased
security of the information that is to be transferred is of
increased concern and these versions/embodiments comprise
further steps. In a first additional step the information
transfer point transfers a crypto key to the information
consumer by means of the secondary bidirectional transfer
network before, during or after transferring information
over the digital video broadcasting system. The
information to be transferred is encoded either by the
information provider or by the information transfer point.
Decoding of the transferred information is performed by
means of the transferred crypto key either in the digital
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video broadcasting receiver of the information consumer or
by the information consumer. When a high reliability of
the transfer of the information is necessary the method
according to the invention further comprises the following
additional steps. First transferring checksums or the
like, of the information that has or will be transferred
via the digital video broadcasting system, via the
secondary bidirectional transfer network to the information
consumer. Secondly checking the transferred information if
it is uncorrupted based on the transferred checksums or the
like. Checking is performed in the digital video
broadcasting receiver of the information consumer or by the
information consumer. Thirdly the digital video
broadcasting receiver of the information consumer or the
information consumer requesting, via the secondary
bidirectional transfer network, to the information transfer
point a resending of corrupted transferred information.
The aforementioned objects are also achieved by a method
for transferring information from an information provider
to an information consumer by means of a digital video
broadcasting system to a digital video broadcasting
receiver of the information consumer. The tranfer is
executed with the support of a secondary bidirectional
transfer network to thereby enable an efficient information
transfer when a demand to transfer information to the
information consumer is originated by the information
consumer. This method according to the invention is
specifically advantageous when an information consumer is
receiving a programme/channel generated from a service
provider and the information consumer desires more
information from that service provider. The
programme/channel can, for example, be a historical
programme that comprises tags that an information consumer
can interpret and use as a request for more information
(such as background information) to the service provider
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which then also becomes an information provider. In
another example the programme/channel can be fed by an
Internet server that continuously feeds the transport
stream with information from the Internet (the information
provider), requested and/or from a standard set, together
with its own IP-address or other server identification.
The information consumer will then provide the information
transfer point with requests for, for example, home pages
and the IP-address these home pages should be sent to, i . a .
the IP-address of the server that the information consumer
is listening to via the digital broadcasting system. The
information transfer point will then provide Internet with
the request for information and where the requested
information should be sent, by means of the IP-address.
The Internet server with the mentioned IP-address will
receive the requested information and add this to the
transport stream that the information consumer receives.
The method according to the invention comprises a number of
steps. First of all the information consumer establishes
an initial contact with an information transfer point via
the secondary bidirectional transfer network with a request
for an information transfer from the information provider
to the information consumer. The information transfer
point can be a part of the information provider, part of
the DVB system, or a separate service. Then the
information consumer provides the information transfer
point, via the secondary bidirectional transfer network,
with transfer configuration information comprising at least
one of either what currently received programme/transport
stream (such as BBC4) or information therein (such as an
IP-address) that the digital video broadcasting receiver of
the information consumer receives. Thereafter the
information transfer point forwards the information request
and the transfer configuration information to the
information provider. Finally the information provider,
based on the transfer configuration information, transfers
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information over the digital video broadcasting system to
the digital video broadcasting receiver of the information
consumer to thereby transfer information from the
information provider to the information consumer in an
efficient way.
The transfer configuration information can further also
advantageously comprise at least one of either a
transmitter frequency, an original network identification,
a transport stream identification, and/or a network
identification of a transport stream of a digital video
broadcasting transmitter that the digital video
broadcasting receiver of the information consumer can
receive.
The method advantageously also, based on the transfer
configuration information, transfers the information to be
transferred to the digital video broadcasting receiver of
the information consumer over a selected transmitter or
transmitters in the digital video broadcasting system. The
transfer configuration information can still further also
advantageosuly comprise at least one of either a
transmitter frequency, an original network identification,
a transport stream identification, and/or a network
identification, of transport streams of transmitters
receivable by the digital video broadcasting receiver of
the predetermined information consumer, the field strengths
of receivable transmitters, or alternative information
transfer routes .
In some versions/embodiments of the invention an increased
security of the information that is transferred is obtained
by having the method according to the invention comprise
further steps. In a first additional step the information
transfer point transfers a crypto key to the information
consumer by means of the secondary bidirectional transfer
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network before, during or after transferring information
over the digital video broadcasting system. The
information to be transferred by the information provider
is encoded. In a final additional step decoding of the
transferred information is performed by means of the
transferred crypto key either in the digital video
broadcasting receiver of the information consumer or by the
information consumer. The method can advantageosuly also
comprise a number of additional steps to ensure a high
reliability. This is accomplished by first transferring
checksums or the like, of the information that has or will
be transferred via the digital video broadcasting system,
via the secondary bidirectional transfer network to the
information consumer. Thereafter checking the transferred
information if it is uncorrupted, based on the transferred
checksums or the like, checking is performed in the digital
video broadcasting receiver of the information consumer or
by the information consumer. Finally the digital video
broadcasting receiver of the information consumer or the
information consumer requesting, via the secondary
bidirectional transfer network, to the information transfer
point a resending of corrupted transferred information.
By providing a method for transferring information from an
information provider to an information consumer over only
selected parts of a digital video broadcasting
system/network, a plurality of advantages over prior art
systems are obtained. By providing information to an
information transfer point of which DVB transmitters is and
optionally which can be received by the information
consumer then the information transfer can be directed
accordingly without having to download the whole system.
The information needed by the information transfer point is
transferred to it by means of a secondary bidirectional
transfer network which can be a readily available telephone
network such as GSM. A high security is obtained by
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transferring crypto keys and the like directly to the
information consumer by means of the secondary
bidirectional transfer network which in that case
preferably is a point to point transfer network. High
5 reliability is obtained by using the secondary
bidirectional transfer network as a back channel for
requests for resending faulty blocks of data. By combining
a cheap, since the whole system bandwidth is not used, high
capacity broadcasting system and a lower capacity or more
10 expensive secondary bidirectional transfer network an
efficient manner of transferring information is obtained
according to the invention. Another advantage of the
invention is the ability to be able to identify an
information consumer either by the DVB receiver identity,
15 the identity of the secondary bidirectional transfer
network transceiver, another identifier which is hardware
independant, or an arbitrary combination of the above.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail for
explanatory, and in no sense limiting, purposes, with
reference to the following figures, in which
Fig. 1 shows a block diagram of one embodiment of a
system according to the invention,
Fig. 2 shows a flow chart of a method according to the
invention,
Fig. 3 shows a flow chart of another method according
to the invention,
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Fig. 4 shows a flow chart of how a high security and
error tolerance is accomplished according to one
method of the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
In order to clarify the system according to the invention,
some examples of its use will now be described in
connection with Figures 1 to 4.
Figure 1 shows a block diagram of one embodiment of a
system according to the invention. As indicated in the
figure and below, certain parts can form smaller or larger
groups. The information that is to be transferred to an
information consumer / terminal 190 can be found at an
information / content provider 100. The other parts that
make up the system are an information transfer point / a
service provider 110, an access information database 120,
a digital video broadcasting (DVB) network / a network
provider 140 with associated cells 145, 146, 147, a
secondary bidirectional transfer network / an interaction
network 130, an information consumer r terminal 190 with a
DVB receiver 191 and a transceiver 192 for the secondary
bidirectional transfer network 130 and optionally means 199
for handling encrypted transmission. The access
information database 120 is used to identify the secondary
bidirectional transfer network 130 and access in that
network to an information consumer. The invention is not
dependent on the exact physical closeness of the different
parts, logically the information consumer 190 is preferably
apart from the other parts 100, 110, 120, 130, 140 of the
system. For example the information transfer point 110
might be part of the information provider 100, or form part
with the access information database 120 and the DVB
network / system 140, or be a completely independent
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service. As mentioned there are many possibilities, but
they do not affect the invention.
Basically the invention locates the information consumer
190 and directs the information only to the whereabouts of
the information consumer 190. The invention utilizes a
broadcasting system 140 for transfer of information to the
information consumer 190. A broadcasting system is very
effective in transferring information to many receivers.
Sometimes a broadcasting system is referred to as a point
to multi point transfer system. A customary manner to
transfer information to ( and from) a single recipient is to
use a so called point to point transfer system. A common
disadvantage with a point to point system is that it is
very expensive per unit of transferred information. A very
attractive advantage with using a DVB system for transfer
of information is its extremely large bandwidth, i.e. it
can transfer large (huge) amounts of data / information in
a very short space of time. By locating a receiver /
consumer of information 190 in a broadcasting system 145,
146, 147 the transfer of information can be directed to
that locality 146, enabling simultaneous use of the network
by spatially separated receivers making the transfer of
information very cost effective. A DVB system can be of a
SFN (Single Frequency Network) nature, be of a more
traditional television broadcasting nature with different
frequency regions / cells 145, 146, 147 or a combination of
both where there can be a SFN covering a nation or large
region and also several different DVB frequency regions
within the same coverage area, each of which can be a small
SFN system. It is possible to direct and send different
information within a SFN as well as in the traditional cell
structure. Sending different information in a SFN requires
great care, but is possible. However, both methods
preferably require that the locality of the receiver to be
known if transmission of information to a single
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information consumer 190 is to be efficient. References in
this application to the identification of a transmitter
means identification of the number of transmitters in a
single frequency network. Broadcasting of information in
a DVB network is done by means of something called a
transport stream that is transmitted at a predetermined
carrier frequency from one or more transmitters. A
transport stream is a multiplex of information comprising
for example elementary streams for one or more programmes
(i.e. programme channels such as BBG1 or SVT1 and not a
time limited show), data, service infarmation, conditional
access control, and synchronization information to mention
a few. The transport stream was devised for multi-
programme applications, i.e. it will usually comprise
elementary streams for more than one programme. An
elementary stream can, for example, be sound (audio),
video, teletext, and data, where, for example, a television
broadcast (a programme) comprises several elementary
streams such as video, mono audio, stereo audio, teletext
etc. The transport stream according to DVB also comprises
data structures comprising a multitude of information. The
invention makes use of one or more pieces of information
within these data structures in dependence on the specific
DVB network. Specifically the invention makes use of a
combination of one or more of the original network
identification (original network id), the transport stream
identification (transportstream id), and the network iden-
tif ication ( network-id ) available in the data structures of
a DVB transport stream.
According to the invention a secondary bidirectional
transfer network 130 is used to transfer the information of
the locality of the information consumer to the information
transfer point 110. One method of acquiring the locality
itself of the information consumer would be to use a GPS
(Global Positioning System) and send the information to the
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information transfer point 110 via the secondary
bidirectional transfer network 130. However, it could be
seen as a disadvantage at times to have to include a GPS
with the information consumer.
Another method of locating the information consumer 190
would be to use the information that a cell based secondary
bidirectional transfer network 130, such as GSM, generates.
Unfortunately that information is usually the propriety of
the operator to that network and thus unavailable to users
outside of that network. The use of that method would then
be specific to a specific secondary bidirectional transfer
network 130 which could be considered a disadvantage at
times.
According to the invention information contained in the
transport stream of a DVB broadcast and possibly the fre-
quency of the transmitter of the received transport stream
is used to locate the information consumer 190. A combi-
nation of one or more of either the transmitter frequency,
the original network identification (original network id),
the transport stream identification (transportstream id),
and/or the network identification (network id), all of the
transport stream in question, will uniquely identify the
transmitter or transmitters (in a SFN) and transport stream
received by the receiver. Different DVB networks will
provide different types of information in the transport
stream and provide a different meaning to original network
identification, transport stream identification, and
network identification. In some DVB networks it is
sufficient with the original network identification which
gives the source of the transport stream and this together
with the transport stream identification will uniquely
identify where and to what transport stream the information
that is to be transferred should be added. If there is no
possibility to add the information to the currently
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received transport stream then there might be a need to
also make use of the network identification which should
give the network from which the transport stream is
received and possibly also the received frequency to thus
5 be able to correctly identify the transmitter from which
the transport stream is received. If the transmitter is
identified then at least a rough location of the
information consumer 190 with its DVB receiver 191 and
secondary bidirectional transfer network transceiver 192 is
10 possible to identify to enable alternative transport
streams that the DVB receiver 191 is able to receive, for
example from the identified transmitter, to be taken into
consideration. In other DVB.networks the original network
identification might have no meaning but the network
15 identification uniquely identifies transmitter and
frequency. In these DVB networks it is fully sufficient to
make use of the network identification and only optionally
the transport identification. Thus according to the
invention, in dependence of the DVB network in question, at
20 least one of either the transmitter frequency, the original
network identification, the transport stream
identification, and/or the network identification is
acquired and transferred to the information transfer point
110 via the secondary bidirectional transfer network 130.
In still other embodiments of the invention the received
programme/channel and/or information within the received
transport stream such as server identification. One is, as
described, enough to at least roughly locate the
information consumer 190 with its DVB receiver 191 and
secondary bidirectional transfer network transceiver 192.
Optionally more receivable transport streams and their
corresponding transmitter frequency, original network
identification, transport stream identification, and/or
network identification, are transferred and optionally
together with their respective field strengths. This
enables the information transfer point 110 to fairly
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exactly pinpoint the information consumer 190 and thereby
determine the most efficient manner in which to transfer
the information. Criteria that the information transfer
point 110 can use could for example be the direction of
travel, free capacity in the different transport streams,
the amount of information to transfer, what transport
streams are receivable, urgency / priority of the request
to transfer information, and so on.
Figure 2 shows a flow chart of a method according to the
invention utilizing, for example, a system according to
figure 1. The method according to figure 2 describes when
a demand for transferring information to an information
consumer arises from an information provider, i.e. a push
system. In a first step, a demand step 210, a demand to
transfer information to an information consumer originates
at an information provider. This demand is transferred as
a request to an information transfer point in a request
step 220. The information transfer point executes a lookup
in a lookup step 230 to establish the known methods of
establishing contact with the information consumer. Based
on the lookup in an establish contact step 240, contact
with the information consumer is established. The step of
establishing contact 240 can optionally involve the
following substeps. Substep SBTN or DVB ? 241 establishes
if the initial contact with the information consumer is to
be done via the secondary bidirectional transfer network
( SBTN ) or via the digital video broadcasting network ( DVB ) .
This information is usually available and established in
the lookup step 230. If the secondary bidirectional
transfer network is to be used then a substep contact ? 242
determines if it is possible to establish contact with the
information consumer. If it is possible to establish
contact with the information consumer, then in substeps DVB
on ? 243 and turn on 244 it is made sure that the DVB
receiver of the information consumer is turned on
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whereafter the procedure continues with step minimum info
250. If no contact was possible to establish in substep
contact ? 242 due to, for example, the fact that the
secondary bidirectional transfer network transceiver of the
information consumer is turned off or the information
transfer point has no or erroneous information about the
secondary bidirectional transfer network of the information
consumer, then one method to continue is to go to substep
DVB broadcast 245. In the substep DVB broadcast 245 a
general call is made via a part of or the complete DVB
network to alert the information consumer that a demand to
transfer information has arisen. If the general call is
received by the information consumer in a substep received
broadcast 246 then the information consumer should turn on
its secondary bidirectional transfer network transceiver
and confirm to the information transfer point in a substep
confirm 247 that it has received the call and thereafter
continue with step minimum info 250. On the other hand if
the information transfer point does not receive a
confirmation or any other contact with the information
consumer within a predetermined space of time then in a
substep timeout 248 the information provider is notified
that no contact was possible to reach with the information
consumer. After initial contact has been made with the
information consumer then in the step minimum info 250 the
information consumer transfers to the information transfer
point via the secondary bidirectional transfer network
transfer configuration information comprising at least one
of either the transmitter frequency, the original network
identification, transport stream identification, and/or
network identification, of the transport stream that the
DVB receiver of the information consumer can receive.
Optionally in a substep optional info 251 the information
consumer also provides the information transfer point with
additional transfer configuration information such as
additional receivable transport streams and corresponding
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information, field strengths of received transmitters,
optional transfer routes etc. Also optionally in a substep
select 252 the information transfer point determines /
selects an optimal route / transport stream to send the
information. Finally in a transfer step 260 the
information is transferred from the information provider to
the information consumer via the digital video broadcasting
network.
Figure 3 shows a flow chart of another method according to
the invention utilizing, for example, a system according to
figure 1. The method according to figure 3 describes when
a demand for transferring information to an information
consumer arises from the information consumer, i.e. a pull
system. In a first step, a need step 210, a need for a
transfer of information to the information consumer
originates in the information consumer itself. In the
optional substeps DVB on ? 311, turn on 312 , SBTN on ? 313 ,
and turn on 314 the information consumer makes sure that
the necessary equipment is turned on. Thereafter the
information consumer in the step minimum info 320 makes an
initial contact with and also transfers to the information
transfer point via the secondary bidirectional transfer
network the request for information and transfer
configuration information comprising at least one of either
the transmitter frequency, the original network
identification, the transport stream identification, and/or
the network identification, of a transport stream that the
DVB receiver of the information consumer can receive.
Optionally in a substep optional info 321 the information
consumer also provides the information transfer point with
additional transfer configuration information such as
additional transport streams, field strengths of received
transmitters, optional transfer routes etc. In a data step
330 the information transfer point retrieves the requested
information from an information provider. Optionally in a
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substep confirmation 331 the information transfer point
confirms to the information consumer if the requested
information is available or not. Also optionally in a
substep select 332 the information transfer point
determines / selects an optimal route / transport stream to
send the information. Finally in a transfer step 360 the
information is transferred from the information provider to
the information consumer via the digital video broadcasting
network.
Figure 4 shows a flow chart of how high security and error
tolerance is accomplished according to one method of the
invention which can be implemented in the methods according
to figures 2 and 3 as substeps to the transfer steps 260
and 360 respectively. In a first step key 461, a crypto
key or the like is transferred to the information consumer
via the secondary bidirectional transfer network. In a
second step transfer 462, encoded information is
transferred to the information consumer via DVB. The
information is decoded / decrypted and a test is made in a
step OK ? 463 to determine if the information was received
intact. If it was received without any errors then in a
step confirmation 466 the information consumer can
optionally confirm, via the secondary bidirectional
transfer network, the reception of the information to the
information transfer point. To make the transfer as
efficient as possible it is probably in most embodiments of
the invention suitable not to confirm correctly received
information. On the other hand if there is an error in the
received information then the information consumer in a
step demand resend 464 makes a demand, via the secondary
bidirectional transfer network, to the information transfer
point to resend the faulty information. The information is
resent in a step resend 465 over the DVB network after
which the procedure proceeds with step OK ? 363.
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The present invention can be put into apparatus-form either
as pure hardware, as pure software or as a combination of
hardware and software. If the method according to the
invention is realised in the form of software, it can be
5 completely independent or it can be one part of a larger
program. The software can suitably be located in a general
purpose computer or in a dedicated computer.
As a summary, the invention can basically be described as
a method which provides an efficient manner of transferring
10 information to an information consumer within a DVB network
using a secondary bidirectional transfer network.
The invention is not limited to the embodiments described
above but may be varied within the scope of the appended
patent claims.
