An inter-entity location checking method and digital content protection system

Abstract

The invention discloses a method for checking the location between entities and a digital content protection system; the method includes: the initiator calculates the first message authentication code based on the maintained sequence number, intercepts the first location checking information from the code, and converts the first message authentication code A location check information and serial number are sent to the responder to start counting down; the responder calculates the second message authentication code based on the maintained serial number in advance, and selects when receiving the first location check information and serial number: whether to authenticate from the second message The code intercepts the second location check information and returns it to the initiator and whether to update the serial number and the second message authentication code; when the initiator receives the second location check information before the end of the countdown, it determines the location check result based on the second location check information; If not received, if the serial number does not reach the upper limit, perform the next position check, and if it reaches the upper limit, end the position check. The invention can effectively reduce the communication overhead caused by the position check between entities in the digital content protection system.

Description

Technical field [0001] The present invention belongs to the field of information security technology, and particularly relates to a method for checking the position of the digital content protection system between an entity. Background technique [0002] Digital and popularity of consumer digital electronic terminal multimedia content so that the user can easily obtain digital content and communication, which makes digital content can easily be pirated in the inter-entity transfer, resulting in the interests of the copyright owner of the digital content a lot of damage. Wherein the called entity, such as a digital electronic apparatus interface, and electronic devices may receive decode and play the digital content; a digital interface such as HDMI (High Definition MultimediaInterface, high definition multimedia interface), DVI (Digital Visual Interface, a digital video interface), and IEEE1394 -1995 and so on. [0003] In order to prevent digital content from being illegally cop...

AI Technical Summary

Problems solved by technology

[0004] Among them, the HDCP standard location check scheme includes two types: one kind of location check scheme requires the responder to use the shared key to answer a random number within a certain period of time, and the waiting time set by the initiator includes the time for the responder to calculate the message authentication code , not only low efficiency but also long waiting time is easy to introduce more unreliable factors; another location check scheme requires the responder to use the shared key to calculate the response of a random number sent by the initiator in advance, and then notify the initiator to calculate Complete, and then the responder returns the calculated value within a certain period of time. The entire location check process requires 4 rounds of sending and receiving messages, and the communication overhead is large.

The DTCP standard location check process also requires the responder to return a value pre-calculated using the shared key within a certain period of time to complete the location check, and the entire location check process requires 6 rounds of sending and receiving messages to complete, which seriously prolongs the location check process. process, which increases the communication overhead between the initiator and the responder

Therefore, in the prior art, there is no practical solution for how to reduce the communication overhead caused by the location check between entities in the digital content protection system

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