Method and system for acquiring service key, conditional access module and subscriber terminal

Abstract

The invention provides a method and a system for acquiring a service key. The method comprises the following steps: a subscriber terminal acquires authorization directing at the present type of service from the network terminal; the authorization is set based on the type of service; if the authorization is broadcasting authorization, the subscriber terminal receives an authorization key from the network terminal by means of broadcasting authorization; if the authorization is bidirectional authorization, the subscriber terminal receives the authorization key from the network terminal by means of bidirectional authorization; wherein, the authorization key is generated by the network terminal based on service information. The invention further provides a conditional access module and the subscriber terminal. In the invention, the subscriber terminal which has broadcasting authorization and bidirectional authorization combines the advantages of the two authorizations, satisfies the need of different subscribers flexibly, improves the subscriber authorization efficiency, promotes subscriber experience and saves resources and power dissipation.

Description

Technical field [0001] The present invention relates to the field of data communication of conditional access systems, in particular to a method and system for obtaining service keys, a user terminal and a conditional access module. Background technique [0002] Conditional acceptance is to implement different protections for various service businesses through effective means and control the users who purchase the corresponding authorization. For example, for various existing fee-paying services, such as pay-TV, pay-per-view TV, video-on-demand, etc., users need to authorize when and what channels they watch. [0003] On the network side, the video, audio or data stream must first be scrambled and encrypted under the control of a control word. These control words are also called keys. For the conditional access system authorized by broadcast mode, the service key is encrypted by the user key to form the authorization management message (EMM: Entitlement Management Message). For s...

AI Technical Summary

Problems solved by technology

[0006] For China Mobile's mobile broadcast business management system (MBBMS: Mobile Broadcast Business Management System) with the help of two-way authentication of telecommunication channels, due to the use of two-way authentication, flexible business authorization can be realized and the success of authorization can be guaranteed. However, it requires The terminal must have a return channel, and the implementation cost is higher than that of broadcast authorization

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