Condition receiving method, condition receiving equipment and condition receiving system

Abstract

The embodiment of the invention provides a condition receiving method, condition receiving equipment and a condition receiving system. The method comprises the following steps of receiving an encrypted program data packet transmitted by a front-end server, wherein the encrypted program data packet carries authorization management information and authorization control information; acquiring an encrypted authorization key and encryption mode descriptive information of the authorization key from the authorization management information carried in the encrypted program data packet; decrypting the encrypted authorization key according to the encryption mode descriptive information, so as to obtain the authorization key; decrypting encryption control words in the authorization control information carried in the encrypted program data packet according to the authorization key, so as to obtain control words; decrypting the encrypted program data packet according to the control words, so as to obtain program content. The method, the equipment and the system provided by the embodiment of the invention can be used for improving the safety of a condition receiving mode and ensuring the benefits of an operator.

Description

technical field [0001] The present invention relates to the technical field of communication, in particular to a conditional access method, device and system. Background technique [0002] The conditional access (CA) system is used to protect the security of program content. In order to prevent illegal users from viewing, suppliers usually use scrambling and descrambling technology to protect programs under the CA system. The method is usually to generate a control word and use the The control word encrypts the program through the internationally accepted encryption algorithm, and transmits the generated encryption key AK to the terminal through the EMM system, so that the terminal obtains the control word CW through the encryption key AK in the EMM system, and then according to the general algorithm The video is played after decryption. Usually, different CA manufacturers have different encryption and decryption methods for AK, but the same manufacturer usually uses the sa...

AI Technical Summary

Problems solved by technology

Usually, different CA manufacturers have different encryption and decryption methods for AK, but the same manufacturer usually uses the same encryption and decryption algorithm for CW on the same project, so once the CA encryption and decryption algorithm is cracked, it will Bring great losses to suppliers

[0003] To solve this problem, the prior art provides a method of constantly changing the control word cw. By continuously changing the control word CW, it is difficult for hackers to crack in a short time to achieve the purpose of protecting program information. However, with the computing power of computers It is becoming more and more powerful, especially with the introduction of cloud computing. The powerful computing power makes CA still unable to avoid the threat of being cracked in a short time

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