HK1112361A - Multimedia content distribution system and method for multiple dwelling unit - Google Patents

Description

Multimedia content distribution system and method for multiple dwelling units

Technical Field

The present invention relates to the field of broadcast program reception systems, and more particularly to subscription-based broadcast program reception and distribution to multiple dwelling units.

Background

Subscription-based broadcast programming distribution for multi-dwelling units facilities such as hotels, apartment buildings, and university campuses can be likened to multiple implementations of a receiving system for a single dwelling unit such as a single household. Will be directed from the present invention to a satellite television broadcast receiving system (e.g., based on DIRECTV)^TMDigital Broadcast System (DBS)) the present invention is discussed. It should be understood, however, that the present invention has applicability to a wide range of broadcast distribution systems, such as cable television systems and distribution systems using the global interconnection of computers and computer networks commonly referred to as the internet.

In general, a satellite television system includes an antenna (including a dish), a low noise block down converter (LNB), a satellite receiver (set-top box), and a television set (TV). Satellite receivers enable users to tune to a desired channel for viewing and are typically connected directly to a TV. Traditionally, if another user desires another television with independent channel control, that user needs a separate set-top box along with the television.

Limited content is typically provided via satellite television systems, a non-limiting example being pay-per-view (PPV) reception of programming. To provide for the reception of such programming, a Conditional Access (CA) module is typically provided with each receiver. However, the CA module itself may be relatively insecure due to the distributed nature of the receivers. This is particularly problematic in hotel rooms (it is believed that such places are often susceptible to thieves stealing the CA module in the receiver).

Also, to provide satellite services to several units in a multi-dwelling unit, a separate satellite receiver box is typically used with each television. In addition to the cost of purchasing additional satellite receivers, each additional satellite receiver is typically placed in a different dwelling unit. Thus, each dwelling unit typically requires a telephone jack to provide a telephone callback link to the set-top box housed therein. It will be understood by those of ordinary skill in the art that the callback link is provided for transmitting billing or other information from the satellite receiver to the video source. In the case where the billing data is temporarily stored at distributed locations, there is a risk that: communication with one or more of the local set-top boxes is interrupted, resulting in billing information not being reported to the broadcast source in a timely manner. This can result in a loss of revenue for the broadcast provider.

It is therefore desirable to provide a multi-dwelling unit multimedia content distribution system and method that enables centralized billing information collection and provision to service providers, as well as security of the CA module itself.

Disclosure of Invention

A method of distributing a video program in a multiple dwelling unit from a receiver device associated with the unit to a plurality of client devices located in the multiple dwelling unit, comprising: receiving a plurality of video programs associated with a plurality of television channels from a signal source; receiving a request for a particular video program associated with a particular television channel from a selected one of a plurality of client devices; confirming that an account associated with the selected client device is authorized to receive the particular video program on the particular television channel; in response to the confirmation, descrambling the particular video program using account data associated with the selected client device; re-scrambling the descrambled particular video program using a local key associated with the selected client device and transmitting the re-scrambled video program to the selected client device; and maintaining account data associated with each client device in the receiver and sending the updated account data to the signal source.

Drawings

An understanding of the present invention will be facilitated by consideration of the following detailed description of the preferred embodiments of the invention taken in conjunction with the accompanying drawings, in which like reference numerals refer to like parts, and:

FIG. 1 shows a block diagram of a system according to an aspect of the invention;

FIG. 2 illustrates a block diagram of a receiver in accordance with an aspect of the subject invention;

FIG. 3 illustrates a flow diagram of a process in accordance with an aspect of the present invention; and the number of the first and second groups,

FIG. 4 illustrates a block diagram of a client device in accordance with an aspect of the subject invention.

Detailed Description

It is to be understood that the figures and descriptions of the present invention have been simplified to illustrate elements that are relevant for a clear understanding of the present invention, while eliminating, for purposes of clarity, many other elements found in typical subscription-based broadcast, reception, and presentation systems and methods. Those of skill in the art may recognize that other elements and/or steps are desirable and/or required in implementing the present invention. However, because such elements and steps are well known in the art, a detailed discussion of such elements and steps will not be presented herein.

In accordance with one aspect of the present invention, the video head-end (head-end) relieves the conditional access and PPV billing functions of the various video set-top boxes in a multiple dwelling unit architecture. As used herein, "video headend" generally refers to a control center of a subscription-based programming transmission system where broadcast signals are received and distributed to multiple dwelling units. In this configuration, the video headend tunes to the desired transponder, de-multiplexes (de-multiplexes) the program stream, and transmits the program stream to various client devices (e.g., set-top boxes) located in the dwelling units. By essentially relocating the conditional access module to the head end, the CA module can be placed in theft by securing the head end (e.g., in a wiring closet).

The headend may utilize conventional copy protection mechanisms to ensure that the content representative signal it delivers to the client device is not "in the clear" on the transmission medium (which may take the form of category 5(Cat5) cabling or QAM-based ethernet, for example). Alternative copy protection schemes include SmartRight (commercially available from Thomson Multimedia, the assignee of the present invention) and IPsec implementation. For purposes of explanation with no limitation, IPsec (abbreviation of IP security protection) is a set of protocols developed by the Internet Engineering Task Force (IETF) to support the secure exchange of packets at the Internet Protocol (IP) layer. IPsec is traditionally employed to implement Virtual Private Networks (VPNs). IPsec supports two encryption modes: a transport mode and a tunnel mode. The transport mode encrypts only the data portion (payload) of each packet, but does not touch the header. The more secure tunnel mode will encrypt both the header and the payload. On the receiving side, the IPsec-compliant device decrypts each packet. The content distribution system and method of the present invention may use either a transport mode or a tunnel mode.

According to one aspect of the invention, each client device transmits a request for programming, such as pay-per-view (PPV), to the headend, which authorizes the transaction (transaction) and sends the requested program to the requesting client device. The headend aggregates the purchase behavior from the client devices and communicates with the service provider (e.g., DIRECTVs) via a callback link in the same manner as a conventional standalone set-top box^TM) Communication is performed. However, the headend sends aggregated program billing information (e.g., multi-service provider accounts) for multiple dwellings to the service provider for processing. It will be readily appreciated that this makes billing easier for the service provider and eliminates the need for a separate callback link (such as a telephone line) to be connected to the client device installed in each dwelling unit.

Referring now to FIG. 1, there is illustrated a block diagram of a system 100 in accordance with an aspect of the subject invention. The system 100 includes an antenna 10 for receiving broadcast video program signals from a broadcast source 15 and a receiver 20 for selectively distributing the received signals to televisions 30, 50, 60. It should be understood that although three televisions are shown, the actual number of televisions may vary widely and may support a significant number of televisions and dwelling units. In the case where the broadcast source includes a satellite 15, the antenna 10 typically includes a dish and a feedhorn for receiving satellite video signals and a Low Noise Block (LNB) for amplifying the received satellite video signals and converting all satellite carrier frequencies to a first IF frequency (intermediate frequency), which is typically about 950 to 1450MHz (megahertz) in the L-band. This down-conversion of the satellite carrier frequency enables connection to the antenna 10 and satellite receiver via the coaxial cable 12 rather than through an expensive waveguide. The feedhorns and LNBs are not shown in the drawing.

Each television 30, 50, 60 is associated with a remote control (not shown) for transmitting a wireless remote control signal including channel selection information to the satellite receiver 20 for which the satellite receiver 20 tunes to the specified channel. The satellite receiver 20 may tune to a different channel for each television set so that each television set may display a different program at the same time. Upon receiving the broadcast video signal from the antenna 10 at the input terminal or port 21, the satellite receiver 20 tunes to a plurality of channels in response to respective remote controller signals, and supplies the video signals from the respective channels to the televisions 30, 50, 60 via the port 22.

Each television 30, 50, 60 may be, but is not limited to, a display supporting HDTV (high definition television) format and/or SDTV (standard definition television) format. Each television 30, 50, 60 is communicatively coupled with an associated client device 35, 55, 65, which client devices 35, 55, 65 are in turn coupled with receiver 20 via communication network 40. The devices 35, 55, 65 may be communicatively coupled with the televisions 30, 50, 60, respectively, via conventional coaxial cables, component connections, and/or digital links (e.g., high-density multimedia input (HDMI) connections).

Network 40 may take the form of a data network, such as a wireless and/or wired network, for example, a User Datagram Protocol (UDP) compatible network, such as a TCP/IP network. In the case where a wireless network 40 (e.g., an 802.11x compatible network) is used, receiver 20 optionally includes a transceiver, such as a Radio Frequency (RF) transmitter, receiver, and antenna. Alternatively, a separate wireless network interface may be used and communicatively coupled with receiver 20. In either case, the satellite receiver 20 and the client devices 35, 55, 65 communicate over the network 40, and the satellite receiver 20 converts the tuned video signals into packets having the network 40 address of the network clients 35, 45, 55 (which may be wireless or wired) as the destination address, thereby enabling the received content to be provided to the televisions 30, 50, 60.

The satellite receiver 20 also includes a callback link 25 port 23 for billing and other administrative purposes associated with each client 35, 45, and 55. The call back link 25 may take the form of a Plain Old Telephone System (POTS) link to a service provider to enable a user to purchase, for example, PPV programming. This callback link may be shared by all televisions 30, 50, 60, operate in response to user interaction with devices 35, 55, 65, and operate depending on the user accounts associated with these devices. Thus, multiple callback data streams from the various devices 35, 55, 65 corresponding to different users' accounts with the service provider may be aggregated and communicated using the same callback link. Advantageously, this enables the operator of the system 100 to store the billing information in a secure location, for example in the receiver 20, rather than in each of the devices 35, 55, 65. In this way, even if any of the devices 35, 55, 65 are individually disconnected, previous billing information (which may correspond to a purchased PPV event) that has not yet been delivered to the broadcast provider is not lost or delayed.

Referring now to fig. 2, a block diagram of a satellite receiver 20' suitable for use in the system 100 of fig. 1 is shown. Receiver 20 'includes a controller 230, e.g., tuners (e.g., tuner/demodulators shown in fig. 2) 205, 210, 215, for controlling the operation of receiver 20'. The controller 230 communicates with other modules using a bus (not shown), such as an inter-integrated circuit (IIC) bus. The term "controller" as used herein represents a variety of different devices including, but not limited to, microprocessors, microcomputers, microcontrollers and controllers. For purposes of simplicity, certain conventional elements associated with satellite receivers such as certain control signals, power signals and/or other elements may not be shown in fig. 2.

Each tuner 205, 210, 215 may be associated with a television/client device pair 30/35, 50/55, 60/65. Alternatively, each tuner may be associated with a separate transponder that is available for tuning. As such, the number of tuners provided may be associated with any of the number of television/client device pairs and/or the number of transponders available for tuning in system 10. Of course, statistical considerations may be applied in determining the number of regulators needed, such that a one-to-one correspondence may not be required. In the case shown in fig. 2, tuners 205, 210, 215 are associated with television/client device pairs 30/35, 50/55, 60/65, respectively. Each tuner tunes to the channel indicated by the controller 230 in response to a request from the corresponding television/client device pair 30/35, 50/55, 60/65 and demodulates the video signal from the channel into a demodulated video stream. The demodulated video stream is fed to the conditional access module 240 for decryption before further distribution.

CA module 240 may take the form of a collection of regular conditional access services that provide the smart card. Each smart card provides the ability to facilitate descrambling a collection of transport streams (associated with a program). When receivers are added to the distribution network, the smart cards may be assigned on a one-to-one basis (one smart card, one receiver). In this process, whenever a new receiver is added to the network, the receiver is authenticated by securely collecting the receiver ID information and associating that information with a particular customer account and a particular smart card. This may be accomplished by having the smart card securely "call back" to the service with information sufficient for association and authentication. Once it is complete, the service sends enough secret information to the smart card to enable it to support program descrambling for a particular receiver ID. In such a configuration, the controller may maintain a mapping of receiver IDs to specific smart cards in order to properly process program requests from the receivers.

Depending on the smart card's capabilities (internal memory, processing power, bandwidth access) and system services, multiple receivers, or even multiple accounts, may be associated with a single card. The mapping may be the same as described above except that a single card may support multiple programs and accounts.

Still further, a secure multi-program, multi-account conditional access processor may be implemented. In this case, a single conditional access processor may be used to support all or multiple groups of receivers on the distribution network. The assignment and authentication process may be the same as described above. Sufficient secure memory, processing power and interface bandwidth can be integrated into the device to support the maximum number of receivers on the distribution network. In such a case, a conventional high-speed secure processor and Field Programmable Gate Array (FPGA) may be used to aggregate the conditional access functions of the multiple smart cards. In either way, reassigning CA services to the headend may reduce the costs and user confusion associated with implementing a CA for the set-top box and simplify the billing functions for users and service providers. For purposes of non-limiting explanation only, receiver 20 'will be discussed in terms of receiver 20' referring to CA module 240 containing a plurality of conventional conditional access modules (e.g., smart cards).

Receiver 20' also includes a packet formatter 250 and a network interface 260. Packet formatter 250 is preferably adapted for use with network interface 260 and network 40. The demodulated video stream (which may comprise MPEG-2 packets, for example) is fed to a packet formatter 250 which formats the transmitted packets into packets, such as IP packets, that are transmittable by the network 40, using conventional methods. The IP packets are then transmitted over the network 40 to the client devices 35, 55, 65, respectively, using the network interface 260. The packet formatter 250 may attach the IP address of one of the devices 35 associated with the tuner 205. Like packet formatter 250, network interface 260 is preferably adapted for use with network 40 (e.g., a TCP/IP network). In the illustrated embodiment, the network interface 260 is communicatively coupled with the packet formatter 250 to receive formatted packets that are communicated to the client devices 35, 55, 65 via the network 40; communicatively coupled with CA module 240 to provide interconnectivity between CA module 240 and client devices 35, 55, 65 via network 40; communicatively coupled with the controller 230 to provide interconnectivity between the controller 230 and the client devices 35, 55, 65 via the network 40. The construction and use of packet formatters and network interfaces is well known in the art.

Receiver 20' also includes a modulator/demodulator (MODEM)270 adapted to communicate with a broadcast (e.g., programming) source via a callback link (e.g., a POTS or internet connection) via port 23.

Referring now to FIG. 3, a process flow 300 is shown in accordance with an aspect of the present invention. Process flow 300 is suitable for use in conjunction with system 100 (fig. 1) including receiver 20' (fig. 2). By way of non-limiting example, controller 230 receives a request for content, such as a particular video program to be viewed, from television set 30 via conventional user interaction with the associated client device 35 (process 310). That is, the device 35 transmits data representing the user request to the receiver 20' via the network 40. Receiver 20' receives the request on port 22 using network interface 260. The request is then forwarded to the controller 230. The controller 230 processes the request and commands the tuner 205 corresponding to the television/client device pair 30/35 to tune the transponder corresponding to the requested channel and video program (process 320). The tuner 205 generates a data stream representative of the signal received via port 21 in response to tuning the transponder corresponding to the requested content, although the other tuners 210, 215 may simultaneously generate their own data streams representative of other channels and video programs being tuned. Controller 230 also processes the request to confirm 30/35 that the requesting television/client device pair is authorized to receive the requested content (process 330). This determination may be similar to the determination conventionally used by CA-enabled satellite receiver set-top boxes. The request may also be forwarded to CA module 240.

If the requesting client device 35 is authorized to receive the requested content, the CA of CA module 240 associated with tuner 205 and/or television/client device pair 30/35, implementing a smart card, receives a data stream representing the requested content from tuner 205 and performs conventional conditional access processing on the received data stream to enable television/client device pair 30/35 to render the content (process 340). For example, the CA module 240 may receive the descrambling key and descramble data representing the content using account data associated with the client device 35 in a conventional manner. The received content may then be re-protected for delivery 30/35 to the television/client device pair via network 40. The processed data stream is then provided to packet formatter 250 for conventional formatting and the formatted, processed data stream is then provided to network interface 260 for provision to client device 35 via network 40 (process 360). Finally, controller 230 may maintain account data associated with television/client device pair 30/35 (process 370), such as by updating account billing information associated with the requesting client device 35 to reflect that the content request was received and/or authorized.

As another non-limiting example, a user may interact with the client device 35 in a conventional manner using a remote control and a Graphical User Interface (GUI) to request presentation of a particular program, such as a PPV event. Receiver 20' receives data representing a user request from client device 35 via network 40, port 22, and network interface 260. According to one aspect of the invention, the controller 230 processes the received request to identify and authenticate the requesting client device 35. Alternatively, the CA module 240 may authenticate the requesting device 35. In either case, the device 35 may be identified and authenticated in a conventional manner, such as by checking the source address of the request, the time of the request, and a digital signature appended to the request. According to alternative aspects of the invention, the tuner 205 may be instructed to tune the transponder corresponding to the received request before, during, or after device identification and/or authentication.

Once identified and authenticated, the controller 230 may process account data corresponding to or related to the requesting client device 35 and the service provider to confirm that the account associated with the requesting client device is authorized to receive the requested content. For example, in the case of a PPV event, controller 230 may confirm authorization to transmit the requested PPV content by: the subscription data for the account associated with the requesting device 35 is checked and updated to reflect the PPV event if the PPV event has not been previously purchased and is available for purchase by the client device 35.

Thereafter, controller 230 may notify CA module 240 of the permission to receive, authorizing CA module 240 to operate with the requesting device 35 to deliver the requested content. In response, the CA module 240 receives the authorized content using conventional conditional access processing, e.g., using account information associated with the requesting device 35 to receive a descrambling key and descramble the authorized content. The CA module 240 may communicate with the requesting device 35 via the network 40 to establish one or more re-scrambling keys for preventing unauthorized reception of content transmissions from the receiver 20' to the requesting device 35. For example, CA module 35 may encrypt a local scrambling key, such as a symmetric key, that is used to re-scramble the content, first using the key to authenticate the digital signature associated with the request. In such a case, only authenticated and authorized requesting devices may receive the key, which may then be used to descramble the requested content in the conventional manner as it is received. By way of further non-limiting explanation, device 35 may sign the request using a private key of a public/private key pair corresponding to device 35 and receive a symmetric key; while the public key of the public/private key pair is used to authenticate the device 35 and to encrypt the symmetric key that is transmitted to the device 35 by the receiver 20'.

Referring now to FIG. 4, there is shown a block diagram of an apparatus 35' in accordance with an aspect of the present invention. The device 35' is suitable for use as any of the client devices 35, 55, 65 in the system 100 of fig. 1. The device 35' includes a port 405 adapted to communicatively connect with the network 40 and a port 465 adapted to couple with a television, such as 30 (fig. 1). The device 35' includes a network interface 410 similar to the network interface 260 (fig. 2). The apparatus 35 'includes a controller 480 for controlling the operation of the apparatus 35', such as the descrambler 420 and the user interface 470. The controller 480 communicates with the other modules using a bus (not shown), such as an inter-integrated circuit (IIC) bus. Likewise, the term "controller" represents various devices including, but not limited to, microprocessors, microcomputers, microcontrollers and controllers. For purposes of simplicity of explanation, certain conventional elements associated with a receiver such as certain control signals, power signals and/or other elements may not be shown in fig. 4.

The controller 480 may be configured to receive a scrambling key (e.g., a symmetric key) from the CA module 240 and forward it to the descrambler 420 for processing the received data representing the content. Descrambler 420 then feeds a conventional decoder, such as an MPEG decoder, for decoding the received content data stream into a decoded stream. Where the associated television 30 is a digital television or other device capable of directly processing the decoded stream, the resulting signal may be provided directly via port 465. In the case of an analog television set 30, the signal may be encoded in a standard television format (such as NTSC, PAL or SECAM) using a conventional encoder 440, processed by a conventional digital-to-analog converter 450, and modulated for reception and presentation by television set 30 using a conventional modulator 460. Optionally, pictures, text, and/or video generated by user interface 470 in response to controller 480 may be combined with or substituted for the decoded video stream in a conventional manner prior to modulation for transmission to television 30.

The controller 480 may operate in conjunction with the user interface 470 in a conventional manner to facilitate user operation of the device 35'. For example, controller 480 and user interface 470 may cooperatively present PPV events available for purchase on a connected television in a conventional manner, check for user selection via user interaction with a remote control, and forward the selection to controller 230 of receiver 20'.

It will be apparent to those skilled in the art that modifications and variations can be made in the apparatus and process of the present invention without departing from the spirit or scope of the invention. It is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims (20)

1. A method of distributing a video program from a receiver device to a plurality of client devices located in a multiple dwelling unit in the multiple dwelling unit, comprising:

receiving a plurality of video programs associated with a plurality of television channels from a signal source;

receiving a request for a particular video program associated with a particular television channel from a selected one of a plurality of client devices;

determining whether an account associated with the selected client device is authorized to receive the particular video program on the particular television channel;

upon confirmation, descrambling the particular video program using account data associated with the selected client device;

re-scrambling the descrambled particular video program using a local key associated with the selected client device and transmitting the re-scrambled video program to the selected client device; and the number of the first and second groups,

account data associated with each client device in the receiver is maintained, and updated account data is sent to the signal source.

2. The method of claim 1, wherein the step of receiving a plurality of video programs comprises tuning to a plurality of transponders.

3. The method of claim 1, wherein the confirming step comprises authenticating the selected client device.

4. The method of claim 3, wherein the confirming step further comprises correlating account data with the selected client device.

5. The method of claim 4, wherein the confirming step is further dependent on the associated account data.

6. The method of claim 5, wherein the maintaining step includes updating the associated account data.

7. The method of claim 1, wherein the descrambling step comprises decrypting at least one scrambling key.

8. The method of claim 7, wherein the re-scrambling step comprises using at least one key different from the scrambling key.

9. The method of claim 1, further comprising sending data representative of the at least one key different from the scrambling key to the selected client device.

10. An apparatus for distributing subscription account based programming of a programming feed to a plurality of client devices located in multiple dwelling units, respectively, the apparatus comprising:

a controller communicatively coupled with the plurality of client devices and operable to receive programming requests from the client devices;

a plurality of tuners responsive to the controller to receive a plurality of programming channels;

a conditional access module responsive to the controller to selectively provide access to the programming channel; and

a memory storing billing information and a plurality of programming source subscription accounts associated with the client device.

11. The apparatus of claim 10, further comprising controller executable code stored in the memory, the code, when executed by the controller, operable to confirm that an account corresponding to a programming request client device is entitled to receive the requested programming.

12. The apparatus of claim 11, wherein the code, when executed by the controller, is operable to cause the conditional access module to descramble a requested programming.

13. The apparatus of claim 12, wherein the code, when executed by the controller, is operable to re-scramble the requested programming.

14. The apparatus of claim 13, wherein the code, when executed by the controller, is operable to transmit the re-scrambled video program to the requesting client device.

15. The apparatus of claim 11, wherein the code, when executed by the controller, is operable to maintain corresponding account data.

16. A method of distributing subscription account based programming of a programming feed to a plurality of associated multiple dwelling units at a common location, comprising:

providing at least one client device in each living unit;

receiving a subscription-based programming at a head end of the common site;

receiving, at the headend, a request for a particular portion of the programming from a selected one of the client devices;

confirming, at the head end, that an account associated with the selected client device is authorized to receive the particular programming;

descrambling, at the headend in response to the confirmation, the particular programming using account data associated with the selected client device;

re-scrambling the descrambled particular programming using a local key associated with the selected client device and transmitting the re-scrambled particular programming to the selected client device; and

account data associated with each client device in the receiver is maintained at the headend and updated account data is sent from the headend to the signal source.

17. The method of claim 16, wherein the confirming step comprises authenticating the selected client device.

18. The method of claim 16, wherein the step of receiving the programming comprises tuning to a plurality of transponders.

19. The method of claim 16, further comprising transmitting data associated with the re-scrambling to the selected client device.

20. The method of claim 16, wherein the maintaining step includes updating the associated account data.