Granted Patent B2

US 7,940,930 · App. 11/918,110 · Granted May 10, 2011

Abstract

Claims (58)

1. A system for scrambling/descrambling packets of a stream of content, each of the packets having a must stay clear (MSC) section which is always kept in the clear, the system comprising physical computing machinery including:

an input handler including:

a receiving module to receive the stream; and

mask module to create, for each of the packets, a data mask which includes all data of the MSC section except for at least one bit of data of the MSC section; and

a scrambling/descrambling device operationally associated with the input handler, the scrambling/descrambling device including:

a receiving module to receive the data mask for each of the packets from the input handler; and

an Initial Value module to determine an Initial Value for each of the packets as a function of the data mask of one of the packets being processed such that the Initial Value is not a function of the at least one bit of data of the MSC section of the one packet being processed, the scrambling/descrambling device being adapted to at least one of scramble and descramble the packets based on the Initial Value and a Control Word.

2. The system according to claim 1 , wherein the at least one bit is location dependent.

3. The system according to claim 1 , wherein the at least one bit is a first bit of a second byte of the MSC section.

4. A system for scrambling/descrambling packets of a stream of content, the stream being associated with a scheme, the system comprising physical computing machine including:

an input handler including:

a receiving module to receive the stream; and

a scheme analyzer to determine the scheme based on a data form of at least one of the packets, each of the packets having a must stay clear (MSC) section which is always kept in the clear;

a mask module to create, for each of the packets, a data mask which includes all data of the MSC section except for at least one bit of data of the MSC section, the data mask being based on the scheme;

an Initial Value module to determine an Initial Value for each of the packets based on the scheme, the Initial Value for each of the packets being a function of the data mask of one of the packets being processed such that the Initial Value is not a function of the at least one bit of data of the MSC section of the one packet being processed; and

a scrambling/descrambling device to at least one of scramble and descramble the packets based on the scheme, wherein the scrambling/descrambling for each of the packets is based on the Initial Value and a Control Word.

5. A method for scrambling/descrambling packets of a stream of content, each of the packets having a must stay clear (MSC) section which is always kept in the clear, the method comprising:

receiving the stream with physical computing machinery;

creating, with the physical computin machinery, for each of the packets, a data mask which includes all data of the MSC section except for at least one bit of data of the MSC section;

determining, with the physical computing machinery, an Initial Value for each of the packets as a function of the data mask of one of the packets being processed such that the Initial Value is not a function of the at least one bit of data of the MSC section of the one packet being processed; and

at least one of scrambling and descrambling the packets, with the physical computing machinery, based on the Initial Value and a Control Word.

6. The method according to claim 5 , wherein the at least one bit is location dependent.

7. The method according to claim 5 , wherein the at least one bit is a first bit of a second byte of the MSC section.

8. A method for scrambling/descrambling packets of a stream of content, the stream being associated with a scheme, the method comprising:

receiving the stream with physical computing machinery;

determining, with the physical computing machinery, the scheme based on a data form of at least one of the packets, each of the packets having a must stay clear (MSC) section which is always kept in the clear;

creating, with the physical computing machinery, for each of the packets, a data mask which includes all data of the MSC section except for at least one bit of data of the MSC section, the data mask being based on the scheme;

determining, with the physical computing machinery, an Initial Value for each of the packets based on the scheme, the Initial Value for each of the packets being a function of the data mask of one of the packets being processed such that the Initial Value is not a function of the at least one bit of data of the MSC section of the one packet being processed; and

scrambling/descrambling, with the physical computing machinery, the packets based on the scheme, wherein the scrambling/descrambling for each of the packets is based on the Initial Value and a Control Word.

9. A system for scrambling/descrambling packets of a stream of content, each of the packets having a must stay clear (MSC) section which is always kept in the clear, the system comprising:

means for receiving the stream;

means for analyzing the stream in order to determine at least one data independent characteristic of each of the packets;

means for receiving the at least one data independent characteristic for each of the packets;

means for determining an Initial Value for each of the packets as a function of the at least one data independent characteristic of one of the packets being processed;

means for introducing entropy into the Initial Value of the packets by performing one of:

artificially creating an adaptation field in at least some of the packets; and

enlarging an existing adaptation field of the at least some packets, such that a length of the adaptation field of the packets is selectable, wherein the adaptation field forms part of the MSC section, the at least one independent characteristic being at least one of a length of the MSC section and the length of the adaptation field; and

means for scrambling/descrambling the packets based on the Initial Value and a Control Word.

10. A system for scrambling/descrambling packets of a stream of content, each of the packets having a must stay clear (MSC) section which is always kept in the clear, the system comprising physical computing machinery including:

an input handler including:

a receiving module to receive the stream;

a characteristic analyzer to analyze the stream in order to determine at least one data independent characteristic of each of the packets; and

a scrambling/descrambling device operationally associated with the input handler, the scrambling/descrambling device including:

a receiving module to receive the at least one data independent characteristic for each of the packets from the input handler; and

an Initial Value module to determine an Initial Value for each of the packets as a function of the at least one data independent characteristic of one of the packets being processed,

wherein the scrambling/descrambling device is adapted to at least one of scramble and descramble the packets based on the Initial Value and a Control Word; and

an adaptation field manager for introducing entropy into the Initial Value of the packets by performing one of:

artificially creating an adaptation field in at least some of the packets; and

enlarging an existing adaptation field of the at least some packets, such that a length of the adaptation field of the packets is selectable,

wherein the adaptation field forms part of the MSC section, the at least one independent characteristic being at least one of a length of the MSC section and the length of the adaptation field.

11. The system according to claim 10 , wherein the Initial Value for each of the packets is also a function of the data content of the MSC section of the one packet being processed.

12. A method for scrambling/descrambling packets of a stream of content, each of the packets having a must stay clear (MSC) section which is always kept in the clear, the method comprising:

receiving the stream with physical computing machinery;

performing, with the physical computing machinery, one of artificially creating an adaptation field in at least some of the packets and enlarging an existing adaptation field of the at least some packets, such that a length of the adaptation field of the packets is selectable, the adaptation field forming part of the MSC section;

analyzing, with the physical computing machinery, the stream in order to determine at least one data independent characteristic of each of the packets, the at least one independent characteristic being at least one of a length of the MSC section and the length of the adaptation field;

determining, with the physical computing machinery, an Initial Value for each of the packets as a function of the at least one data independent characteristic of one of the packets being processed; and

at least one of scrambling and descrambling, with the physical computing machinery, the packets based on the Initial Value and a Control Word.

13. The method according to claim 12 , wherein the determining also includes determining the Initial Value for each of the packets as a function of the data content of the MSC section of the one packet being processed.

Assignments (8)