Method and system for distributing service secret keys

Abstract

The invention discloses a method for distributing service secret keys; the method sets a corresponding secret key seed set aiming at each service and stores a corresponding relation between the service and the secret key seed set in a safety region of a condition receiving card; when service information needs to be broadcast, the network side selects a secret key seed from the corresponding secretkey seed set to generate a service secret key; a corresponding identifier of the secret key seed contained in EMM is issued to the terminal through a broadcasting channel; the terminal sends the received EMM to the condition receiving card; the condition receiving card obtains the identifier of the secret key seed from the EMM and determines the corresponding secret key seed; and according to thesecret key seed, a mode which is the same as the network side is adopted to generate the service secret key. The invention also discloses a system and the method for distributing the service secret keys. The invention is applied, can realize the user authentication and the secret key distribution in a unidirectional broadcasting network, and can reduce the broadcasting amount of the service secret key, save the channel resource and reduce the time delay for a user to wait the service secret key.

Description

technical field [0001] The invention relates to multimedia broadcasting technology, in particular to a service key distribution method and system, and a key distribution method. Background technique [0002] In the current multimedia broadcasting system, the conditional access method based on the hierarchical key system is widely used for conditional access, that is, the user key (UK) is used to encrypt the service key (SK), and the service key (SK) is used to encrypt the program stream key (CW), and use the program stream key CW to encrypt the program stream. figure 1 It is a schematic structural diagram of the hierarchical key system of the existing multimedia broadcasting system. see figure 1 , the existing hierarchical key system is divided into four layers, and the key distribution scheme based on the hierarchical key system includes the following four levels of interaction: [0003] The first layer: authentication. Through the authentication process, the mobile TV ...

AI Technical Summary

Problems solved by technology

[0008] 1) When the number of users reaches a certain level, the amount of encrypted service keys that need to be broadcast will be very large, which increases the burden on the server, wastes precious channel resources, and lengthens the delay for users to wait for the service key

[0009] 2) The hierarchical key system is based on a two-way communication network, which requires users to upload their user keys to verify the legitimacy of users, therefore, it is not suitable for one-way broadcast networks

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