Recording medium, recording method and apparatus, reproducing method and apparatus, data transmitting method, and data decrypting method

Abstract

A recording medium having an area in which data that has been encoded with a first error correction code is recorded, wherein data that can be decoded with a second error correction code that is different from the first error correction code is recorded to the area along with the data that has been encoded with the first error correction code, and wherein the data that can be decoded with the second error correction code composes at least part of encryption key data.

1 - 43 . (canceled)  
   
   
       44 . A reproducing method for a recoding medium, comprising the steps of: 
 decoding data that is read from an area of the recording medium, data that has been encrypted and that has been encoded with a first error correction code being recorded to the area, in the area, data that can be decoded with a second error correction code that is different from the first error correction code being recorded along with the data encoded with the first error correction code;    generating decryption key data using data that has been decoded with at least the second correction code; and    decrypting the data that has been encoded with the first error correction code using the generated key data.    
   
   
       45 . The reproducing method for the recording medium as set forth in  claim 44 , further comprising the step of: 
 generating the key data using an error pattern of the data that has been decoded with the second error correction code.    
   
   
       46 . The reproducing method for the recording medium as set forth in  claim 44 , 
 wherein a reading position of data that can be decoded with the second error correction code and that is read from the area is changed whenever the data is reproduced from the recording medium.    
   
   
       47 . The reproducing method for the recording medium as set forth in  claim 44 , 
 wherein a reading order of data that can be decoded with the second error correction code and that is read from the area is changed whenever the data is reproduced from the recording medium.    
   
   
       48 . The reproducing method for the recording medium as set forth in  claim 44 , 
 wherein the key data generating step is performed by reading the data from the area to a semiconductor memory and generating the key data using data that is read to the semiconductor memory.    
   
   
       49 . The reproducing method for the recording medium as set forth in  claim 44 , 
 wherein the data that can be decoded with the second error correction code is data that can be also decoded with the first error correction code.    
   
   
       50 . The reproducing method for the recording medium as set forth in  claim 44 , 
 wherein the first error correction code and the second error correction code are used to encode at least two encoding sequences in respective directions, the first error correction code and the second error correction being different only in the encoding sequences, the data that can be decoded being data of which predetermined data is repeated as one unit of one of the two encoding sequences in the respective directions.    
   
   
       51 . The reproducing method for the recording medium as set forth in  claim 44 , 
 wherein the first error correction code and the second error correction code are a code with which a C 1  sequence in a vertical direction is encoded and a code with which a C 2  sequence in a diagonal direction is encoded, respectively, the first error correction code and the second error correction code being different in their interleave lengths, the data that can be decoded being predetermined data repeated as one unit of the C 1  sequence.    
   
   
       52 . A reproducing apparatus for a recoding medium, comprising: 
 a head portion for reading data from the recording medium, data that has been encrypted and that has been encoded with a first error correction code being recorded to the area, in the area, data that can be decoded with a second error correction code that is different from the first error correction code being recorded along with the data encoded with the first error correction code;    a decoding process portion for performing a decoding process for an output signal of the head portion;    a generating portion for decoding output data of the decoding process portion with the second error correction code and generating decryption key data using data that has been decoded with at least the second correction code; and    a decrypting portion for decrypting output data of the decoding process portion using the generated key data.    
   
   
       53 . The reproducing apparatus for the recording medium as set forth in  claim 52 , 
 wherein the generating portion is configured to also generate the key data using an error pattern of the data that has been decoded with the second error correction code.    
   
   
       54 . The reproducing apparatus for the recording medium as set forth in  claim 52 , 
 wherein a reading position of data that can be decoded with the second error correction code and that is read from the area is changed whenever the data is reproduced from the recording medium.    
   
   
       55 . The reproducing apparatus for the recording medium as set forth in  claim 52 , 
 wherein a reading order of data that can be decoded with the second error correction code and that is read from the area is changed whenever the data is reproduced from the recording medium.    
   
   
       56 . The reproducing apparatus for the recording medium as set forth in  claim 52 , 
 wherein the data that is read from the area is read to a semiconductor memory and the key data is generated using data that is read to the semiconductor memory.    
   
   
       57 . The reproducing apparatus for the recording medium as set forth in  claim 52 , 
 wherein the data that can be decoded with the second error correction code is data that can be also decoded with the first error correction code.    
   
   
       58 . The reproducing apparatus for the recording medium as set forth in  claim 52 , 
 wherein the first error correction code and the second error correction code are used to encode at least two encoding sequences in respective directions, the first error correction code and the second error correction being different only in the encoding sequences, the data that can be decoded being data of which predetermined data is repeated as one unit of one of the two encoding sequences in the respective directions.    
   
   
       59 . The reproducing apparatus for the recording medium as set forth in  claim 52 , 
 wherein the first error correction code and the second error correction code are a code with which a C 1  sequence in a vertical direction is encoded and a code with which a C 2  sequence in a diagonal direction is encoded, respectively, the first error correction code and the second error correction code being different in their interleave lengths, the data that can be decoded being predetermined data repeated as one unit of the C 1  sequence.    
   
   
       60 - 67 . (canceled)  
   
   
       68 . A data decrypting method, comprising the steps of: 
 decoding data with a second error correction code, the data having been received as data that has been encrypted and that has been encoded with a first error correction code along with data that can be decoded with a second error correction code that is different from the first error correction code;    generating decryption key data using data that has been decoded with at least the second error code; and    decrypting the data that has been encoded with the first error correction code using the generated key data.    
   
   
       69 . The data decrypting method as set forth in  claim 68 , further comprising the step of: 
 generating the key data using an error pattern of the data that has been decoded with the second error correction code.    
   
   
       70 . The data decrypting method as set forth in  claim 68 , 
 wherein a reading position of data that can be decoded with the second error correction code is changed whenever the data is decoded.    
   
   
       71 . The data decrypting method as set forth in  claim 44 , 
 wherein a reading order of data that can be decoded with the second error correction code is changed whenever the data is decoded.    
   
   
       72 . The data decrypting method as set forth in  claim 68 , 
 wherein the key data generating step is performed by reading the data to a semiconductor memory and generating the key data using data that is read to the semiconductor memory.    
   
   
       73 . The data decrypting method as set forth in  claim 68 , 
 wherein the data that can be decoded with the second error correction code is data that can be also decoded with the first error correction code.    
   
   
       74 . The data decrypting method as set forth in  claim 68 , 
 wherein the first error correction code and the second error correction code are used to encode at least two encoding sequences in respective directions, the first error correction code and the second error correction being different only in the encoding sequences, the data that can be decoded being data of which predetermined data is repeated as one unit of one of the two encoding sequences in the respective directions.    
   
   
       75 . The data decrypting method as set forth in  claim 68 , 
 wherein the first error correction code and the second error correction code are a code with which a C 1  sequence in a vertical direction is encoded and a code with which a C 2  sequence in a diagonal direction is encoded, respectively, the first error correction code and the second error correction code being different in their interleave lengths, the data that can be decoded being predetermined data repeated as one unit of the C 1  sequence.