| 摘要 |
PROBLEM TO BE SOLVED: To provide transmission system and method that can reduce a network load with enhancing security.SOLUTION: A first head encryption unit 2a encrypts a head block D0 by using ID. A non-head encryption unit 2b encrypts a next block by using an encrypted block. A first transmitter 2c transmits first encrypted data 6 and ID to a second transmission device 3. A first holding unit 2d holds end encrypted data. A second head encryption unit 2e encrypts a head block D4 by using end encrypted data E(D3). A second transmitter 2f transmits a second encrypted data 7 to a second transmission device 3 with the second head encryption unit 2e. A first decoder 3a performs decoding from the first encrypted data 6 and ID. A second decoder 3c decodes the second encrypted data 7 received from the first transmission device 2 by using the end encrypted data held by the second holding unit 3b. |
