Pointers to encrypted data in RTP header

• US 20020090086A1
• Filed: 12/18/2001
• Published: 07/11/2002
• Est. Priority Date: 12/18/2000
• Status: Active Grant

• Current Assignee: Irdeto B.V. (MultiChoice Group Ltd.)
• Original Assignee: Irdeto Eindhoven BV (MultiChoice Group Ltd.)
• Inventors: Van Rijnsoever, Bartholomeus Johannes
• Granted Patent: US 7,447,313 B2
• Time in Patent Office: Days
• US Class Current: 380/207
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/65 Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04N 21/23476 by partially encrypting, e.g. encrypting the ending portion of a movie
• CPC Class Codes: H04N 21/23897 by partially encrypting, e.g. encrypting only the ending portion of a movie
• CPC Class Codes: H04N 21/8455 involving pointers to the content, e.g. pointers to the I-frames of the video stream
• CPC Class Codes: H04N 5/783 Adaptations for reproducing at a rate different from the recording rate
• 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

Frame-formatted user data is real-time transmitted whilst thereon effecting before transmission a frame-based encryption procedure. In particular, before subjecting to the encryption procedure, localizing data is joined to the data frame and placed into predetermined governance locations that are excluded from the subsequent encrypting.

Claims

1. A method for real-time transmitting or retransmitting frame-formatted user data whilst thereon effecting before such (re-)transmitting an encryption procedure,

said method being characterized by the step of, associated to subjecting said user data to said encryption procedure, joining to said user data appropriate frame localizing data and placing such frame localizing data into predetermined governance locations which, just as well as header informations, are excluded from subsequent said encryption procedure.

2. A method as claimed in claim 1, whilst subjecting only a part of said user data to said encryption procedure whilst providing for encryption localizing data in said governance locations to discriminate between encrypted and non-encrypted parts of said user data.

3. A method as claimed in claim 1 or 2, wherein such governance locations are header extension information locations.

4. A method as claimed in claim 1 or 2, wherein said user data after encryption are transmitted in RTP-packets, and wherein said user data are encrypted on a level of said RTP packet.

5. A method as claimed in claim 1 or 2, wherein said user data are encrypted on a frame level.

6. A method as claimed in claims 4 or 5 wherein said transmission allows for imparting partial frames to a packet, as well as allowing to impart a plurality of frames to a single packet.

7. A method as claimed in claim 3, wherein such header extension information location has a plurality of frame localizing data.

8. A method as claimed in claim 1 or 2, wherein such governance locations are placed within a separate hint track.

9. A system arranged for implementing a method as claimed in claim 1 and having transmission means for real-time transmitting or retransmitting frame-formatted user data and encryption means for effecting before such (re-)transmitting an based encryption procedure on said user data,

said system being characterized by comprising next to said encryption means joining means for joining to said user data frame localizing data and placing such frame localizing data into predetermined governance locations which, just as well as header informations, are excluded from subsequent said encryption.

10. A system as claimed in claim 9, and being arranged for interfacing to Internet as a transmission medium.

11. A transmitter apparatus being arranged for use as a station in a system as claimed in claim 9.

12. A signal produced by a station as claimed in claim 11.

13. A receiver apparatus being arranged for use as a station in a system as claimed in claim 9 and having decryption means for upon reception decrypting user data that had been subject to said encryption procedure for outputting user data so decrypted as based on frames containing said user data.

14. A receiver apparatus as claimed in claim 13, wherein said decryption means are operational on a frame level.

15. A receiver apparatus as claimed in claim 13, wherein said decryption means are operational on a packet level.