The Research And Implementation Of The Integration Of Conditional Access System Based On Advanced Security Chip

With the rapid development of network information technology,operators of broadcasting and television are facing with severe security challenges.The traditional set-top boxes that base on normal chips are becoming more and more easily to be clone,so the operators' interests are seriously threatened.How to deal with these challenges can protect the interests of operators from the pirated set-top boxes and provide information security for operators' security.Condition access corporations propose the base on hardware & software approach that the software boot and run the hardware architecture of the security chip.How to integrate CA system into set-top box products is the main problem that solves in this thesis.The process of integrated CA system is always facing many problems,such as different API,long software development cycle,high requirements for safety performance,and unstable operation of CA system.This thesis focuses on the method and performance of integrated CA system on advanced security chip.At first,the thesis introduced the research status of CA integrated software at domestic and abroad,and then analyzed the problems that existed in the software architecture of the current CA system.Proposed a new achtecture to complete the integration software development and design.The workflow of system initialization and the CA system were reseached.How to fast integrated CA subsystem is the main problem for set top box manufacturers.This topic studied how to integrate the conditional access software successfully and run on the advanced security chip.The semaphore was used to solove the resources conflict of data storage,data receiver,data descrambler and smart card.The exclusive access of the mechanism for critical resources prevented the system from deadlocking.At the same time,the thesis designed mainly sub-modules in the CA system.The cycle of integrated CA has been shortened.This cycle is reduced from the average of three months to one and a half months and the timesheet wes reduced from 6 to 2.2 person months.In addtion,the thesis proposed a fast change channel solution based on the security chip.This topic supplied the design a more efficiency process of the change channel and verified the new flow in the actual environment.It proposed a design scheme that prioritized condition access descramble,reduced to operation the system IO and adopted multithread concurrent execution mode.The production which has been optimized reduced the time of FCC from 2000 ms to 1500 ms.The software of production design has good security and it solves the problem of balance of security and efficiency of the conditional access system.The integrated software developed based on this security chip is portable and easily applied for the system of DVB-C,DVB-T,and DVB-S.