Networked multimedia overlay system

• US 7,545,935 B2
• Filed: 05/11/2004
• Issued: 06/09/2009
• Est. Priority Date: 10/04/2002
• Status: Expired due to Fees

• Current Assignee: Tech 5 SAS
• Original Assignee: Scientific-Atlanta Incorporated (Cisco Systems, Inc.)
• Inventors: Claussen, Paul J.
• Primary Examiner(s): CERVETTI, DAVID GARCIA
• Application Number:
  US10/842,823
• Publication Number:
  US 20050005287A1
• Time in Patent Office: 1,855 Days
• Field of Search: 380/200, 380/210, 380/228, 380/239, 725/31, 725/74, 725/119, 725/131, 725/151
• US Class Current: 380/200
• 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 method for providing a networked overlay system, the method comprising the steps of:

receiving downstream signals encrypted according to a first encryption 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 according to a second encryption scheme to provide a second encrypted program;

storing the second encrypted program;

concurrently storing a portion of the at least one program encrypted according to the first encryption scheme by;

buffering the clear program, the clear program having packets;

buffering the at least one program encrypted according to the first encryption scheme, the at least one program having packets;

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

wherein packets of the clear program are dropped until such time as the at least one predetermined critical packet is identified, wherein a corresponding critical packet in the at least one program encrypted according to the first encryption scheme that is in accordance with the predetermined critical packet is stored;

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 is capable of decrypting programs encrypted according to the second encryption scheme, providing the stored second encrypted program to the requesting remote device;

wherein if the decryption device is capable of decrypting programs encrypted according to the first encryption scheme but not the second encryption 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;

concurrently buffering the at least one corresponding critical packet in the at least one program encrypted according to the first encryption scheme;

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;

combining the passed clear program packets with the buffered at least one corresponding critical packet encrypted according to the first encryption scheme to provide a partially encrypted program; and

providing the partially encrypted program to the requesting remote device.

2. The method of claim 1, further comprising the step of modulating the requested stored program to a predetermined frequency.

3. The method of claim 1, further comprising the step of modulating the second encrypted program or the partially encrypted program to a predetermined frequency.