Networked multimedia overlay system

• US 20050005287A1
• Filed: 05/11/2004
• Published: 01/06/2005
• Est. Priority Date: 10/04/2002
• Status: Active Grant

• Current Assignee: Tech 5 SAS
• Original Assignee: Scientific-Atlanta LLC (Cisco Systems, Inc.)
• Inventors: Claussen, Paul J.
• Granted Patent: US 7,545,935 B2
• Time in Patent Office: Days
• US Class Current: 725/31
• CPC Class Codes: H04N 21/4147 PVR [Personal Video Recorder] H04N5/76 takes precedence ; arrangements for broadcast with accumulation-type receivers H04H20/40
• CPC Class Codes: H04N 21/4334 Recording operations recording of a television signal H04N5/76; arrangements for recording or accumulating broadcast information or broadcast-related information H04H60/27
• CPC Class Codes: H04N 21/43615 Interfacing a Home Network, e.g. for connecting the client to a plurality of peripherals home Audio Video Interoperability [HAVI] data switching networks H04L12/2805
• CPC Class Codes: H04N 21/4363 Adapting the video stream to a specific local network, e.g. a Bluetooth® network
• CPC Class Codes: H04N 21/440245 the reformatting operation being performed only on part of the stream, e.g. a region of the image or a time segment
• CPC Class Codes: H04N 21/44029 for generating different versions
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/44055 by partially decrypting, e.g. decrypting a video stream that has been partially encrypted
• CPC Class Codes: H04N 7/163 by receiver means only
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58

Abstract

Systems and methods are disclosed for providing encrypted downstream signals to a plurality of receiver devices 130, 135, 140, where the devices 130, 135, 140 may have different decryption devices. A receiver network (i.e., a networked multimedia system) includes a splitter/isolation module (SIM) 125, a primary set-top terminal (STT) 130, and at least one remote device 135, 140. The remote devices 135, 140 communicate with the primary STT 130 via the SIM 125 over coaxial cable. Accordingly, the remote devices 135, 140 are capable of requesting and receiving stored programs via the networked multimedia overlay system. Depending upon the decryption device included in the requesting remote STT 135, 140, the primary STT 130 sends a stored program encrypted according to that decryption device.

Claims

1. A network overlay system, comprising:

a primary device for receiving downstream signals having a first encrypted scheme from a communications network, the downstream signals including a plurality of programs, for selectively storing at least one program in a second encrypted scheme and portions of the at least one program having the first encrypted scheme, and for providing requested stored programs; and

a plurality of remote devices coupled to the primary device, each remote device for receiving the downstream signals having the first encrypted scheme, and for requesting and receiving a stored program,

wherein the requested program received by a requesting remote device is one of a partially encrypted program or a program having the second encrypted scheme.

2. The system of claim 1, the primary device comprising:

a modulator for modulating the requested program to a predetermined frequency.

3. The system of claim 1, the primary device comprising:

a first decryptor for decrypting the at least one program providing a clear program;

a second encryptor for encrypting the clear program providing a second encrypted program; and

a storage device for storing the second encrypted program.

4. The system of claim 3, the primary device further comprising:

a first buffer for receiving the clear program, the clear program having packets;

a second buffer for receiving the at least one program, the at least one program having packets;

a critical packet selector coupled to the first buffer for detecting predetermined critical packets;

a switch coupled to the second buffer and controlled by the critical packet selector, wherein the switch is in position for dropping packets of the at least one program until such time as a predetermined critical packet is identified and the switch allows a critical packet in the at least one program that is in accordance with the identified critical packet in the clear program to pass to the storage device.

5. The system of claim 4, wherein the storage device includes the at least one stored program having the second encrypted scheme and first encrypted critical packets of the at least one program.

6. The system of claim 5, the primary device further comprising:

a second decryptor for decrypting the requested second encrypted program to provide a requested clear program;

a third buffer for receiving the requested clear program;

a fourth buffer for receiving the first encrypted critical packets;

a second critical packet selector for detecting the predetermined critical packets included in the requested clear program;

a first switch coupled to the third buffer and controlled by the critical packet selector, wherein the switch is in position to pass the requested clear program until such time as the predetermined critical packet is detected and the switch allows the predetermined critical packet to drop; and

a combiner for combining the passed clear program with the first encrypted critical packets to provide a partially encrypted program.

7. The system of claim 1, further comprising a splitter isolator module (SIM) for receiving the downstream signals and for providing the downstream signals to at least one of the primary device and the plurality of remote devices;

for receiving the requested program and for providing the stored program to the plurality of remote devices, and for receiving at least one reverse command signal provided by at least one of the plurality of remote devices and for providing the reverse command signal to the primary device.

8. The system of claim 7, further comprising a modulator for modulating the requested program to a predetermined frequency.

9. The system of claim 8, wherein the predetermined frequency is excluded from a frequency range of the downstream signals.

10. A method for providing a networked overlay system, the method comprising the steps of:

receiving downstream signals having a first encrypted scheme at a primary device and a plurality of remote devices, the downstream signals including a plurality of programs;

in the primary device, decrypting at least one of the plurality of programs to provide a clear program;

encrypting the clear program to provide a second encrypted program;

storing the second encrypted program;

storing a portion of the at least one program having the first encrypted scheme; and

providing a requested stored program to a requesting remote device,

wherein the requested stored program provided is one of a partially encrypted program including the portion of the at least one program having the first encrypted scheme or the second encrypted program.

11. The method of claim 10, further comprising the step of modulating the requested stored program to a predetermined frequency.

12. The method of claim 10, further comprising the steps of:

buffering the clear program, the clear program having packets;

buffering the at least one program, the at least one program having packets;

detecting at least one predetermined critical packet in the clear program;

wherein packets of the at least one first encrypted program are dropped until such time as a predetermined critical packet is identified, wherein a critical packet in the at least one first encrypted program that is in accordance with the predetermined critical packet is stored.

13. The method of claim 12, further comprising the steps of:

in response to a requesting remote device for a stored program,

determining the decryption device of the requesting remote device;

dependent upon the decryption device, accessing the stored program,

wherein if the decryption device decrypts the second encrypted program, providing the stored second encrypted program;

wherein if the decryption device decrypts the first encrypted scheme, providing the stored second encrypted program to a second decryptor device;

decrypting the stored second encrypted program to provide a clear program;

buffering the clear program;

buffering the portion of the at least one program;

detecting the at least one predetermined critical packet in the clear program;

wherein packets of the clear program are passed through until such time as the at least one predetermined critical packet is detected and the at least one predetermined critical packet is dropped from the program; and

combining the passed clear program packets with the buffered portion of the at least one program to provide the partially encrypted program.

14. The method of claim 12, further comprising the step of modulating the second encrypted program or the partially encrypted program to a predetermined frequency.

15. A method for requesting and receiving a stored program depending upon a remote device'"'"'s decryptor in a networked overlay system including a primary device, a splitter isolator module (SIM), and a plurality of remote devices, the method comprising the steps of:

at at least one of a plurality of remote devices,

receiving user input signals;

processing the user input signals to determine whether the stored program is indicative of one of a downstream signal or a stored program; and

transmitting the user input signals that are indicative of the stored program to the primary device via the SIM; and

at the primary device,

processing the user input signals and determining the requesting remote device'"'"'s decryptor device;

providing the stored program depending upon the remote decryptor device,

wherein the stored program comprises a second encrypted program and a portion of a first encrypted program, and

wherein the second encrypted program is provided if the requesting remote device includes a decryptor device for decrypting the second encrypted program, and wherein a partially encrypted program including the portion of the first encrypted program is provided if the requesting remote device includes a decryptor device for decrypting a first encryption scheme.

16. The method of claim 15, wherein the downstream signal is encrypted with the first encryption scheme.