Decoding and encoding data

• US 8,666,079 B2
• Filed: 05/29/2008
• Issued: 03/04/2014
• Est. Priority Date: 05/29/2008
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Kendall, Chad William, Sankar, Narendra
• Primary Examiner(s): Hailu, Teshome
• Application Number:
  US12/129,348
• Publication Number:
  US 20090296935A1
• Time in Patent Office: 2,105 Days
• Field of Search: 380/277, 380/44, 380/45, 380/255, 380/269, 380/200, 380/201, 380/210, 380/217
• US Class Current: 380/277
• CPC Class Codes: H04L 2209/12 Details relating to cryptographic hardware or logic circuitry
• CPC Class Codes: H04L 2209/30 Compression, e.g. Merkle-Damgard construction
• CPC Class Codes: H04L 9/088 Usage controlling of secret information, e.g. techniques for restricting cryptographic keys to pre-authorized uses, different access levels, validity of crypto-period, different key- or password length, or different strong and weak cryptographic algorithms network architectures or network communication protocols for using time-dependent keys in a packet data network H04L63/068

Abstract

A method includes receiving data which has been encoded according to a first higher complexity protection scheme and compressed. The method also includes decompressing the data. The method also includes decoding the data according to the first higher complexity protection scheme using a first higher complexity key. The method also includes encoding at least the first portion of the data according to a second higher complexity protection scheme using a second higher complexity key. The method also includes encoding at least a second portion of the data according to a lower complexity protection scheme using a lower complexity key.

Claims

1. A method comprising:

receiving data which has been encrypted and compressed;

decrypting, by a processor, the data using a decryption key;

decompressing, by a processor, the data;

generating, by a processor, a scrambling key based on a first portion of the data after the first portion of the data has been decrypted according to a decryption scheme using the decryption key and decompressed;

encrypting, by a processor, the first portion of the data using an encryption key; and

scrambling, by a processor, a second portion of the data different from the first portion of the data using the scrambling key, the scrambling having a lower complexity than the encrypting.

2. The method of claim 1, wherein the scrambling the second portion of the data includes scrambling all of the data, except the first portion of the data which is encrypted, using the scrambling.

3. An apparatus comprising:

at least one processor; and

at least one memory device coupled to the at least one processor, the at least one memory device comprising instructions stored thereon that, when executed by the at least one processor, are configured to cause the apparatus to;

receive data which has been encrypted and compressed;

decrypt the data using a decryption key;

decompress the data;

generate a scrambling key based on a first portion of the data after the first portion of the data has been decrypted according to a decryption scheme using the decryption key and decompressed;

encrypt the first portion of the data using an encryption key; and

scramble a second portion of the data different from the first portion of the data using the scrambling key, the scrambling having a lower complexity than the encrypting.

4. The apparatus of claim 3, wherein the scrambling includes scrambling all of the data, except the first portion of the which is encrypted, using the scrambling key.

5. The apparatus of claim 3 wherein:

the data includes video data which has been encrypted and compressed;

the decrypting includes decrypting the video data scheme using the decryption key;

the decompressing includes decompressing the video data;

the generating includes generating the scrambling key based on a first portion of the video data;

the encrypting the first portion includes encrypting at least the first portion of the video data using the encryption key; and

the scrambling the second portion includes scrambling at least a second portion of the video data using the scrambling key.

6. The apparatus of claim 3 wherein:

the receiving includes successively receiving data frames which have been encrypted and compressed;

the decrypting includes successively decrypting each data frame using the decryption key;

the decompressing includes successively decompressing each data frame;

the generating includes generating a scrambling key for each data frame based on a first portion of the data frame;

the encrypting the first portion includes successively encrypting at least a first portion of each data frame using encryption key; and

the scrambling the second portion includes successively scrambling at least a second portion of the data using the scrambling key generated for the respective data frame.

7. A non-transitory computer-readable storage medium including executable code that, when executed, is configured to cause a computing device to:

receive data;

decrypt a first portion of the data using a decryption key;

decompress the first portion of the data;

generate a scrambling key based on the decrypted first portion of the data after the first portion of the data has been decrypted according to a decryption scheme using the decryption key and decompressed; and

descramble a second portion of the data different from the first portion of the data using the scrambling key, the descrambling having a lower complexity than the decrypting.

8. The storage medium of claim 7, wherein the code is further configured to cause the computing device to send the decrypted and descrambled data to a graphics processor.

9. The storage medium of claim 7, wherein code is further configured to cause the computing device to:

receive video data;

decrypt a first portion of the video data using the decryption key;

generate the scrambling key based on the decrypted first portion of the video data; and

descramble a second portion of the video data using the scrambling key.

10. The storage medium of claim 7, wherein the code is further configured to cause the computing device to:

successively receive data frames;

successively decrypt a first portion of each data frame using the decryption key;

successively generate a scrambling key for each respective data frame based on the decrypted first portion of the respective data frame; and

successively decrypt a second portion of each respective data frame using the generated scrambling key for the respective data frame.