Broadcast data access controller communication system

• US 5,999,623 A
• Filed: 11/05/1997
• Issued: 12/07/1999
• Est. Priority Date: 11/05/1997
• Status: Expired due to Term

• Current Assignee: Globalstar Incorporated
• Original Assignee: Globalstar Incorporated
• Inventors: Wiedeman, Robert A., Monte, Paul A., Bowman, Philip J.
• Primary Examiner(s): Swann, Tod R.
• Assistant Examiner(s): Darrow, Justin T.
• Application Number:
  US08/964,539
• Time in Patent Office: 762 Days
• Field of Search: 380/20, 380/21, 380/49, 348/5.5, 395/186
• US Class Current: 380/239
• CPC Class Codes: H04H 60/15 on receiving information
• CPC Class Codes: H04H 60/23 using cryptography, e.g. encryption, authentication, key distribution
• CPC Class Codes: H04L 2209/601 Broadcast encryption
• CPC Class Codes: H04L 9/00 Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
• CPC Class Codes: H04L 9/083 involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP]
• CPC Class Codes: H04N 21/2347 involving video stream encryption
• CPC Class Codes: H04N 21/26613 for generating or managing keys in general key distribution for secret or secure communication involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP] H04L9/083; network support of key management H04L63/06; key management for network security in communication control or processing H04W12/04
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• 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

Disclosed is a method and apparatus for enabling an authorized receiver station to decrypt encrypted information broadcast by a transmitter station, and for decrypting the information within the authorized receiver station. The method includes steps of storing a predetermined Subscription Key value in the authorized receiver station and, using the predetermined Subscription Key value, generating a Decryption Key value. In a next step the transmitter station broadcasts a signal which includes the encrypted information. After the broadcasted signal is received at the authorized receiver station, the authorized receiver station performs a predefined algorithm. The predefined algorithm uses the generated Decryption Key value to decrypt the encrypted information from the received signal.

Claims

1. A method for enabling only authorized ones of a plurality of receiver stations to obtain access to first information transmitted by a transmitter station, the method comprising the steps of:

at the transmitter station, performing a first predefined algorithm to generate Subscription Key values for individual ones of the respective authorized receiver stations, wherein the first predefined algorithm is a function of a predetermined Decryption Key value;

providing the Subscription Key values to the individual ones of the respective authorized receiver stations;

at each of the authorized receiver stations, performing a second predefined algorithm using the Subscription Key value provided to the authorized receiver station, and generating a resultant value that equals the predetermined Decryption Key value;

transmitting a first signal from the transmitter station, the first signal including an encrypted version of the first information;

receiving the first signal at each of the receiver stations, and within each individual one of the authorized receiver stations, performing a third predefined algorithm using the resultant value to decrypt the encrypted version of the first information, thereby enabling the authorized receiver station to obtain access to the first information in decrypted form.

2. A method as set forth in claim 1, wherein the step of performing the first predefined algorithm is performed using User Key values of the respective authorized receiver stations, and wherein the step of performing the second predefined algorithm within each authorized receiver station is performed using the User Key value of the respective authorized receiver station.

3. A method as set forth in claim 1, wherein the step of providing the Subscription Key values is performed by:

transmitting an information signal from the transmitter station, the information signal including (a) the Subscription Key values for the respective authorized receiver stations, (b) Tag values corresponding to respective ones of the Subscription Key values, and (c) UID values;

receiving the information signal at each of the receiver stations, and within each receiver station;

comparing the UID values from the information signal to a UID value stored in the receiver station, and, if any of the UID values from the information signal are equal to the UID value stored in the receiver station,

storing the Subscription Key value and the Tag value corresponding to the Subscription Key value in the receiver station at a storage location identified by the Tag value.

4. A method as set forth in claim 1, wherein the step of providing the Subscription Key values is performed by:

transmitting an information signal from the transmitter station, the information signal including the Subscription Key values for the respective authorized receiver stations;

receiving the information signal at each of the receiver stations; and

within each receiver station;

deriving Tag values and UID values corresponding to respective ones of the Subscription Key values,

comparing the derived UID values to a UID value stored in the receiver station, and, if any of the derived UID values are equal to the UID value stored in the receiver station,

storing the Subscription Key value and the derived Tag value corresponding to the Subscription Key value in the receiver station at a storage location identified by the derived Tag value.

5. A method as set forth in claim 4, wherein the step of deriving Tag values and UID values includes the steps of:

parsing the information signal received at each of the receiver stations according to a predetermined data transmission format; and

assigning a predetermined Tag value and UID value corresponding to respective one of the Subscription Key values parsed from the information signal according to the predetermined data transmission format.

6. A method as set forth in claim 1, wherein the step of providing the Subscription Key values is performed by storing the respective Subscription Key values in the respective authorized receiver stations.

7. A method as set forth in claim 6, wherein the step of storing the respective Subscription Key values in the respective authorized receiver stations is performed via a user-interface.

8. A method as set forth in claim 7, wherein prior to the step of storing the respective Subscription Key values, a step is performed of:

providing storage devices wherein are stored respective ones of the Subscription Key values, and wherein the step of storing is performed by loading the Subscription Key values from the storage devices into the respective authorized receiver stations.

10. A method as set forth in claim 1, wherein the step of transmitting is performed prior to the step of performing the second predefined algorithm, and the provided Subscription Key values are stored in the respective authorized receiver stations at storage locations identified by respective first Tag values, wherein the first signal also includes respective second tag values for the respective authorized receiver stations, and wherein within each authorized receiver station, the step of performing the second predetermined algorithm further includes the steps of:

prior to performing the second predetermined algorithm and in response to receiving the first signal, comparing the second Tag value of the first signal to each of the Tag values stored in the authorized receiver station, and if any of the stored Tag values are equal;

retrieving the Subscription Key value stored in the authorized receiver station at the storage location identified by the second Tag value; and

performing the second predetermined algorithm with the retrieved Subscription Key value.

29. A method as set forth in claim 1, wherein the step of providing includes the steps of:

transmitting an information signal from the transmitter station, the information signal including the predetermined Subscription Key values, the predetermined Subscription Key values being in a predetermined sequence;

receiving the information signal at the authorized receiver stations; and

within each authorized receiver station, performing steps of;

selecting at least one of the Subscription Key values from the information signal, based on the predetermined sequence of the Subscription Key values; and

storing the selected at least one Subscription Key value.

9. A method for enabling only authorized ones of a plurality of receiver stations to obtain access to first information transmitted by a transmitter station, the method comprising the steps of:

at the transmitter station, performing a first redefined algorithm to generate Subscription Key values for the respective authorized receiver stations, wherein the first predefined algorithm is a function of a predetermined Decryption Key value;

providing the Subscription Key values to the respective authorized receiver stations;

at each of the authorized receiver stations, performing a second predefined algorithm using the Subscription Key value provided to the authorized receiver station, and generating a resultant value that equals the predetermined Decryption Key value;

transmitting a first signal from the transmitter station, the first signal including an encrypted version of the first information;

receiving the first signal at each of the receiver stations, and within each individual one of the authorized receiver stations, performing a third predefined algorithm using the resultant value to decrypt the encrypted version of the first information, thereby enabling the authorized receiver station to obtain access to the first information in decrypted form,

wherein the provided Subscription Key values are stored in the respective authorized receiver stations at storage locations identified by Tag values, the step of performing the second predetermined algorithm further includes the steps of;

prior to performing the second predetermined algorithm and in response to an expiration of a predetermined time period, retrieving the stored Subscription key value associated with the Tag value corresponding to the predetermined time period; and

performing the second predetermined algorithm with the retrieved Subscription Key value.

11. A method for enabling only authorized ones of a plurality of receiver stations to obtain access to first information transmitted by a transmitter station, the method comprising the steps of:

at the transmitter station, performing a first predefined algorithm to generate Subscription Key values for the respective authorized receiver stations, wherein the first predefined algorithm is a function of a predetermined Decryption Key value;

providing the Subscription Key values to the respective authorized receiver stations;

at each of the authorized receiver stations, performing a second predefined algorithm using the Subscription Key value provided to the authorized receiver station, and generating a resultant value that equals the predetermined Decryption Key value;

transmitting a first signal from the transmitter station, the first signal including an encrypted version of the first information;

receiving the first signal at each of the receiver stations, and within each individual one of the authorized receiver stations, performing a third predefined algorithm using the resultant value to decrypt the encrypted version of the first information, thereby enabling the authorized receiver station to obtain access to the first information in decrypted form,

wherein the step of providing includes providing the Subscription Key values and respective Tag values to the respective authorized receiver stations, and the step of generating the resultant value further includes the step of;

storing in the authorized receiver station the resultant value and the Tag value corresponding to the Subscription Key value provided to the authorized receiver station at a storage location identified by the Tag value.

30. A method as set forth in claim 11, wherein the Tag value stored in the authorized receiver station specifies a particular time, and within the authorized receiver station, prior to the performance of the third predefined algorithm, steps are performed of:

recognizing an occurrence of the particular time specified by the Tag value stored in the authorized receiver station; and

retrieving the stored resultant value associated with the Tag value specifying the particular time, wherein the step of performing the third predefined algorithm within the authorized receiver station is performed in response to the retrieving step.

31. A method as set forth in claim 11, wherein the first signal also includes respective Tag values for the respective authorized receiver stations, and wherein within each authorized receiver station, further steps are performed of:

prior to performing the third predefined algorithm and in response to receiving the first signal, comparing the Tag values from the first signal to the Tag value stored in the authorized receiver station to determine whether any of the Tag values from the first signal are equal to the Tag value stored in the authorized receiver station, and if any one of the Tag values from the first signal is determined to be equal to the Tag value stored in the authorized receiver station, performing steps of;

retrieving the resultant value from the storage location identified by the Tag value stored in the authorized receiver station, and wherein the step of performing the third predefined algorithm is performed in response to the retrieving step.

12. A method for enabling only authorized ones of a plurality of receiver stations to obtain access to first information transmitted by a transmitter station, the method comprising the steps of:

at the transmitter station, performing a first predefined algorithm to generate Subscription Key values for the respective authorized receiver stations, wherein the first predefined algorithm is a function of a predetermined Decryption Key value;

providing the Subscription Key values to the respective authorized receiver stations;

at each of the authorized receiver stations, performing a second predefined algorithm using the Subscription Key value provided to the authorized receiver station, and generating a resultant value that equals the predetermined Decryption Key value;

transmitting a first signal from the transmitter station, the first signal including an encrypted version of the first information;

receiving the first signal at each of the receiver stations, and within each individual one of the authorized receiver stations, performing a third predefined algorithm using the resultant value to decrypt the encrypted version of the first information, thereby enabling the authorized receiver station to obtain access to the first information in decrypted form,

wherein the third predefined algorithm is performed in response to an occurrence of a triggering event, the triggering event being an occurrence of a predetermined time.

13. A method for enabling only authorized ones of a plurality of receiver stations to obtain access to first information transmitted by a transmitter station, the method comprising the steps of:

at the transmitter station, performing a first predefined algorithm to generate Subscription Key values for the respective authorized receiver stations, wherein the first predefined algorithm is a function of a predetermined Decryption Key value;

providing the Subscription Key values to the respective authorized receiver stations;

at each of the authorized receiver stations, performing a second predefined algorithm using the Subscription Key value provided to the authorized receiver station, and generating a resultant value that equals the predetermined Decryption Key value;

transmitting a first signal from the transmitter station, the first signal including an encrypted version of the first information;

receiving the first signal at each of the receiver stations, and within each individual one of the authorized receiver stations, performing a third predefined algorithm using the resultant value to decrypt the encrypted version of the first information, thereby enabling the authorized receiver station to obtain access to the first information in decrypted form,

wherein the third predefined algorithm is performed in response to an occurrence of a triggering event, the triggering event being an occurrence of a predetermined time-of-day.

14. A method as set forth in claim 13, wherein upon the occurrence of the triggering event, the transmitter station broadcasts the first signal.

15. A method for enabling an authorized receiver station to decrypt encrypted information transmitted by a transmitter station, and for decrypting the encrypted information with the authorized receiver station, the method comprising the steps of:

storing a predetermined Subscription Key value in the authorized receiver station;

retrieving the predetermined Subscription Key value stored in the authorized receiver station;

performing a first predefined algorithm within the authorized receiver station using the predetermined Subscription Key value and a unique non-public value that is prestored in the authorized receiver station, to generate a Decryption Key value;

transmitting a signal from the transmitter station, the signal including the encrypted information;

receiving the signal at the authorized receiver station; and

within the authorized receiver station, performing a second predefined algorithm using the Decryption key value to decrypt the encrypted information.

18. A method as set forth in claim 15, wherein the first predefined algorithm is a function of (a) the predetermined Subscription Key value and (b) the unique, non-public value that is prestored in the authorized receiver station as a User Key value.

20. A method as set forth in claim 15, wherein prior to the performance of the step of storing, steps are performed of:

transmitting an information signal from the transmitter station, the information signal including the predetermined Subscription Key value, a corresponding Tag value, and a corresponding UID value;

receiving the information signal at the authorized receiver station;

within the authorized receiver station, comparing the UID value from the information signal to a UID value stored in the authorized receiver station; and

if they are equal,

performing the step of storing; and

performing a further step of storing the Tag value in a manner so that the Tag value identifies the predetermined Subscription Key value stored in the authorized receiver station.

21. A method as set forth in claim 20, wherein the first information specifies the Tag value, and wherein the step of retrieving is performed by:

comparing the Tag value of the first information to the Tag value stored in the authorized receiver station, and if they are equal,

retrieving the Subscription Key and generating decryption Key values identified by the Tag value stored in the authorized receiver station.

16. A method for enabling an authorized receiver station to decrypt encrypted information transmitted by a transmitter station, and for decrypting the encrypted information with the authorized receiver station, the method comprising the steps of:

storing a predetermined Subscription Key value in the authorized receiver station;

retrieving the predetermined Subscription Key value stored in the authorized receiver station;

performing a first predefined algorithm within the authorized receiver station using the predetermined Subscription Key value, to generate a Decryption Key value;

transmitting a signal from the transmitter station, the signal including the encrypted information;

receiving the signal at the authorized receiver station; and

within the authorized receiver station, performing a second predefined algorithm using the Decryption key value to decrypt the encrypted information,

wherein the second predefined algorithm is performed in response to an occurrence of a triggering event, the triggering event being an occurrence of a predetermined time.

17. A method as set forth in claim 16, wherein the predetermined time is specified by the transmitter station.

19. A method for enabling an authorized receiver station to decrypt encrypted information transmitted by a transmitter station, and for decrypting the encryted information with the authorized receiver station, the method comprising the steps of:

storing a predetermined Subscription Key value in the authorized receiver station;

retrieving the predetermined Subscription Key value stored in the authorized receiver station;

performing a first predefined algorithm within the authorized receiver station using the predetermined Subscription Key value, to generate a Decryption Key value;

transmitting a signal from the transmitter station, the signal including the encrypted information;

receiving the signal at the authorized receiver station; and

within the authorized receiver station, performing a second predefined algorithm using the Decryption key value to decrypt the encrypted information,

wherein the first predefined algorithm is a function of (a) the predetermined Subscription Key value and (b) a User Key value stored in the authorized receiver station,

and wherein prior to the performance of the step of storing, the predetermined Subscription Key value is determined by performing the first predefined algorithm using a first value that is predetermined to be equal to the Decryption Key value and a second value that equals the User Key value.

22. A Broadcast Data Access Controller (BDAC) communication system, comprising:

at least one transmitter station;

at least one authorized receiver station, said at least one authorized receiver station including storage means for storing at least one predetermined Subscription Key value and a unique, non-public value;

first control means coupled to said transmitter station, said first control means for transmitting a first signal from said transmitter station to said authorized receiver station, said first signal including first information encrypted in accordance with a predefined encryption algorithm and second information specifying that said predetermined Subscription Key value be accessed within said authorized receiver station;

second control means coupled to said receiving station, said second control means being responsive to said second information for accessing said Subscription Key value and said unique, non-public value stored in said storage means and for performing a first predefined algorithm based on said accessed Subscription Key value and on said unique, non-public value to generate a Decryption Key value; and

means coupled to said second control means for performing a second predefined algorithm based on said Decryption Key value to decrypt said encrypted first information of said first signal.

23. A BDAC communication system as set forth in claim 22, wherein said unique, non-public value is a User Key value, and wherein said first predefined algorithm operates on said User Key value and said Subscription Key value accessed by said second control means.

24. A BDAC communication system as set forth in claim 22, wherein said receiver station further stores a UID value, wherein said first control means is also for transmitting a second signal from said transmitter station prior to said transmission of said first signal, wherein said second signal includes said at least one predetermined Subscription Key value and a corresponding at least one UID value, and wherein said second control means is responsive to said second signal for comparing said at least one UID value from said second signal to said stored UID value and for storing said at least one Subscription Key value from said second signal in said first storage means if said at least one UID value from said second signal equals said stored UID value.

25. A BDAC communication system as set forth in claim 22, wherein said second control means and said means for performing said second predefined algorithm form a Decryption module, said Decryption module being detachably coupled to said at least one receiver station.

26. A BDAC communication system as set forth in claim 25, wherein said unique, non-public value is a User Key value, wherein said Decryption module further comprises a further storage means for storing said User Key value, and wherein said first predefined algorithm operates on said User Key value and said Subscription Key value accessed by said second control means.

27. A BDAC communication system as set forth in claim 26, wherein said further storage means also stores a UID value, and wherein said UID value is externally readable and said User Key value is not externally readable.

28. A method for enabling only authorized ones of a plurality of receiver stations to obtain access to first information transmitted by a transmitter station, the method comprising the steps of:

performing a first predefined algorithm to generate Subscription Key values for the respective authorized receiver stations, wherein the first predefined algorithm is function of a predetermined Decryption Key value;

providing the Subscription Key values to the respective authorized receiver stations;

transmitting a signal from the transmitter station, the signal including an encrypted version of the first information, the signal also including second information;

receiving the signal at each of the receiver stations; and

within each individual one of the authorized receiver stations;

performing a second predefined algorithm using the Subscription Key value provided to the authorized receiver station in combination with a unique, non-public value that is prestored in the authorized receiver station, and generating a resultant value that equals the predetermined Decryption Key value, and

performing a third predefined algorithm using the resultant value to decrypt the encrypted version of the first information, thereby enabling the authorized receiver station to obtain access to the first information in decrypted form.

35. A method as set forth in claim 28, wherein the step of providing the Subscription Key values is performed by:

transmitting an information signal from the transmitter station, the information signal including (a) the Subscription Key values for the respective authorized receiver stations, (b) Tag values corresponding to respective ones of the Subscription Key values, and (c) identification values associated with respective ones of the authorized receiver stations;

receiving the information signal at each of the receiver stations, and within each receiver station;

comparing the identification values from the information signal to an identification value stored in the receiver station, and, if any one of the identification values from the information signal is equal to the identification value stored in the receiver station,

storing the Subscription Key value and corresponding Tag value associated with the one identification value in the receiver station at a storage location identified by the Tag value.

36. A method as set forth in claim 28, wherein the second information specifies Tag values, wherein the provided Subscription Key values are stored in the authorized receiver stations at storage locations identified by respective Tag values, and wherein in response to receiving the second information, and prior to the performance of the second predefined algorithm, each authorized receiver station performs steps of:

comparing the Tag values from the second information to the Tag values stored in the authorized receiver station, and, if any of the Tag values from the second information signal are equal to any one of the Tag values stored in the authorized receiver station, retrieving the Subscription Key value stored at the storage location identified by the stored Tag value, wherein the second predefined algorithm is performed using the Subscription Key value retrieved in the retrieving step.

32. A method for enabling an authorized receiver station to decrypt encrypted information transmitted by a transmitter station, and for decrypting the encrypted information with the authorized receiver station, the method comprising the steps of:

storing a predetermined Subscription Key value in the authorized receiver station;

retrieving the predetermined Subscription Key value stored in the authorized receiver station;

performing a first predefined algorithm within the authorized receiver station using the predetermined Subscription Key value, to generate a Decryption Key value;

transmitting a signal from the transmitter station, the signal including the encrypted information;

receiving the signal at the authorized receiver station; and

within the authorized receiver station, performing a second predefined algorithm using the Decryption key value to decrypt the encrypted information,

wherein prior to the storing step, steps are performed of;

transmitting an information signal from the transmitter station, the information signal including first and second information, the first information specifying that the predetermined Subscription Key value is being transmitted, the second information including the predetermined Subscription Key value;

receiving the information signal at the authorized receiver station; and

within the authorized receiver station, performing steps of;

recognizing that the predetermined Subscription Key value is included in the received information signal, based on the first information included in the information signal, and then performing the step of storing the predetermined Subscription Key value in the authorized receiver station.

33. A method for enabling an authorized receiver station to decrypt encrypted information transmitted by a transmitter station, and for decrypting the encrypted information with the authorized receiver station, the method comprising the steps of:

storing a predetermined Subscription Key value in the authorized receiver station;

retrieving the predetermined Subscription Key value stored in the authorized receiver station;

performing a first predefined algorithm within the authorized receiver station using the predetermined Subscription Key value, to generate a Decryption Key value;

transmitting a signal from the transmitter station, the signal including the encrypted information;

receiving the signal at the authorized receiver station; and

within the authorized receiver station, performing a second predefined algorithm using the Decryption key value to decrypt the encrypted information,

wherein prior to the performance of the retrieving step, the authorized receiver station performs a step of recognizing an occurrence of a particular time, wherein the retrieving step is performed in response to the recognizing step, and wherein the first predefined algorithm is performed in response to the retrieving step.

34. A method as set forth in claim 33, wherein the particular time is specified by a tag value stored in said authorized receiver station.

37. A method for enabling only authorized ones of a plurality of receiver stations to obtain access to first information transmitted by a transmitter station, the method comprising the steps of:

performing a first predefined algorithm to generate Subscription Key values for the respective authorized receiver stations, wherein the first predefined algorithm is function of a predetermined Decryption Key value;

providing the Subscription Key values to the respective authorized receiver stations;

transmitting a signal from the transmitter station, the signal including an encrypted version of the first information, the signal also including second information;

receiving the signal at each of the receiver stations;

and within each individual one of the authorized receiver stations;

performing a second predefined algorithm using the Subscription Key value provided to the authorized receiver station, and generating a resultant value that equals the predetermined Decryption Key value, and

performing a third predefined algorithm using the resultant value to decrypt the encrypted version of the first information, thereby enabling the authorized receiver station to obtain access to the first information in decrypted form,

wherein in response to the resultant value being generated, the resultant value is stored at a storage location identified by a respective Tag value, wherein the receiving step is performed after the performance of the second predefined algorithm, wherein the second information specifies Tag values, and wherein in response to receiving the signal, the authorized receiver station performs steps of;

comparing the Tag values from the second information to the respective Tag value stored in the authorized receiver station, and, if any of the Tag values from the second information signal are equal to the respective Tag value stored in the authorized receiver station,

retrieving the resultant value stored at the storage location identified by the Tag value stored in the authorized receiver station, and wherein the third predefined algorithm is performed in response to the retrieving step.

38. A decryption module, comprising:

a memory, said memory storing at least one first predetermined value and a second predetermined value that comprises a unique, non-public value;

a controller, said controller being bidirectionally coupled to said memory, said controller for retrieving the at least one first predetermined value and said second predetermined value that comprises said unique, non-public value from said memory for performing a first predefined algorithm based on the at least one first predetermined value and said second predetermined value to generate a resultant value; and

a decryption processor, said decryption processor being bidirectionally coupled to said controller, said decryption processor also for being bidirectionally coupled to a front end block of a receiver station that is in communication with a transmitter station which broadcasts encrypted information, said decryption processor for performing a second predefined algorithm using the resultant value generated by said controller to decrypt the encrypted information after the encrypted information is received by said front end block and provided to said decryption processor.

40. A decryption module as set forth in claim 38, wherein after said controller generates said resultant value said controller stores said resultant value in said memory at a storage location identified by a respective Tag value, the respective Tag value specifying a particular time, wherein the controller includes means for recognizing an occurrence of the particular time specified by the Tag value, and wherein the controller retrieves the resultant value from said memory and provides said resultant value to said decryption processor in response to said recognizing means recognizing the occurrence of the particular time specified by the Tag value, said decryption processor being responsive to receiving said resultant value for performing said second predefined algorithm.

42. A decryption module as set forth in claim 38, wherein said at least one first predetermined value is stored in said memory at a storage location identified by a respective Tag value, wherein said transmitter station broadcasts information specifying the Tag value along with the encrypted information, wherein the controller is bidirectionally coupled to said front end block for receiving the information specifying the Tag value from the front end block after the information is received by the front end block from the transmitter station, said controller being responsive to receiving the information for associating the information with the Tag value stored in said memory, for subsequently retrieving the at least one first predetermined value from said memory, and for then performing the first predefined algorithm to generate the resultant value, wherein after generating the resultant value said controller provides the resultant value to said decryption processor, said decryption processor being responsive to receiving resultant value for performing said second predefined algorithm.

39. A decryption module, comprising:

a memory, said memory storing at least one first predetermined value;

a controller, said controller being bidirectionally coupled to said memory, said controller for retrieving the at least one first predetermined value from said memory for performing a first predefined algorithm based on the at least one first predetermined value to generate a resultant value; and

a decryption processor, said decryption processor being bidirectionally coupled to said controller, said decryption processor also for being bidirectionally coupled to a front end block of a receiver station that is in communication with a transmitter station which broadcasts encrypted information, said decryption processor for performing a second predefined algorithm using the resultant value generated by said controller to decrypt the encrypted information after the encrypted information is received by said front end block and provided to said decryption processor,

wherein the at least one first predetermined value is stored in the memory at a storage location identified by a respective Tag value, the respective Tag value specifying a particular time, wherein the controller includes means for recognizing an occurrence of the particular time specified by the Tag value, and wherein the controller retrieves the at least one first predetermined value from said memory for performing the first predefined algorithm in response to said recognizing means recognizing the occurrence of the particular time specified by the Tag value.

41. A decryption module, comprising:

a memory, said memory storing at least one first predetermined value;

a controller, said controller being bidirectionally coupled to said memory, said controller for retrieving the at least one first predetermined value from said memory for performing a first predefined algorithm based on the at least one first predetermined value to generate a resultant value; and

a decryption processor, said decryption processor being bidirectionally coupled to said controller, said decryption processor also for being bidirectionally coupled to a front end block of a receiver station that is in communication with a transmitter station which broadcasts encrypted information, said decryption processor for performing a second predefined algorithm using the resultant value generated by said controller to decrypt the encrypted information after the encrypted information is received by said front end block and provided to said decryption processor,

wherein after said controller generates said resultant value said controller stores said resultant value in said memory at a storage location identified by a respective Tag value, wherein said transmitter station broadcasts information specifying the Tag value along with the encrypted information, wherein the controller is bidirectionally coupled to said front end block for receiving the information specifying the Tag value from the front end block after the information is received by the front end block from the transmitter station, said controller being responsive to receiving the information for associating the information with the Tag value stored said memory, for subsequently retrieving the resultant value from said memory, and for then providing said resultant value to said decryption processor, said decryption processor being responsive to receiving said resultant value for performing said second predefined algorithm.

43. A communication system, comprising:

a transmitter station for broadcasting a signal that includes encrypted information;

at least one receiver station for receiving said signal, said at least one receiver station storing at least one first predetermined value that is input to said at least one receiver station and further storing a non-public value, related to an identification of the receiver station, that is prestored in said at least one receiver station, said at least one receiver station for performing a first predefined algorithm using the at least one predetermined value and the non-public value to generate a resultant value, said at least one receiver station also for performing a second predefined algorithm using the resultant value to decrypt the encrypted information included in the received signal.