| 摘要 |
The invention concerns a method for encryption of information that is sent as a digital signal in packet- form, wherein the packet to be encrypted is chosen according to a predetermined selection strategy, encryption data is introduced into the packet being encrypted, and at least one portion of the packet that is recorded for encryption is encrypted. The invention further concerns an arrangement 1 for encryption of a digital signal to be sent in packet form, containing elements 2, 4, 5, 7, 8 for selecting the packet to be encrypted among the packets being sent, an element 23 for recording the encryption data in the packet, and an element 24 for encrypting the packet that is recorded for encryption. The system according to the invention for encryption of information to be sent as a digital signal in packet form comprises elements 25, 26, 27 for encoding video, audio and data signals and for forming a packet, a multiplexer 28 for combining in packet form converted signals connected to a program, a program multiplexer 29 for combining several programs into a bit stream, an element 1 for encoding a signal, a channel encoder 30 for transforming the bit stream being transferred to the transmission channel 31, an element 32 for decoding the channel code, an element 33 for decoding the encryption, an element 34 for separating the signals in packet form connected to the program, and elements 35, 36, 37 for decompiling the packet and decoding the video, audio and data signals. The element 1 for encryption of a signal contains furthermore elements 2, 4, 5, 7, 8 for selecting the packet to be encoded among the packets being sent, an element 23 for introducing the encryption data into the packet, and an element 24 for encrypting the packet that is registered for encryption. <IMAGE>
|
