Cryptographic Algorithm In Digital Transmission Content Protection To Achieve

With the development of the network, computer calculation ability and the high volume storage devices, the multimedia contents are used and spread widely. On the other hand, because of the easy copy feather of the multimedia contents, they are copied and distributed illegally with little costs, which leads the content creator under the awkard condition. Content protection technology gives an effect solution to the above circumstance. The media contents transmitting in the network are under the protection of the content protect protocol which combined the cryptology and the authentication method. But how the content protection protocol satisfies the high throughout of data process of the multimedia is a hard nut.The prime point for the implementation of the content protection protocol, which is based on the cryptography field: encryption and decryption of the data, is to implement the cryptography algorithms used in the content protection protocol effectively. For the DTCP(Digital Transmission Content Protection)system, our focus is on one the achievement of the hard core for hash algorithm; SHA-1 and SHA-256, the AES algorithm and the ECC point multiplication on Prime field.For SHA-1 function, implemented with 4 stage pipelines, there is only on adder operation on the critical path, which can work with the throughout of 3.1Gb/s. Under the basis of analyzing SHA-1 algorithm, the improvement for the circuit structure of SHA-256 can be got: working under the max frequency of 370Mhz, the hard core have the throughout of 2.9Gb/s. In the protocol of the DTCP, the broadcasting mode of the source devices requires the AES module must have the G/s above data process ability. Using the deep pipeline method to achieve the hardware, we get the AES module has the throughout of 50Gb/s under the frequency of 410MHz. The prime field ECC point multiplication module used the 3 stages parallel Montgomery modular multiplier, for the modulo which is the 160bits prime, the core can do the point multiplication 500 times per second.