Method of recovering and managing security-related information for downloadable conditional access system

A method of managing security-related information in a DCAS, the method comprising:

• storing a session key and security-related information of a target server, the session key being used by the target server and based on a predetermined security protocol, the security-related information being required to be securely maintained and being encrypted using a particular key, the session key and the encrypted security-related information being mapped to each other;
• transmitting a recovery key to the target server in preparation for a loss of the security-related information, encrypted using the particular key, in the target server;
• receiving a recovery request message about the security-related information, encrypted using the particular key, from the target server, the recovery request message including information associated with the session key;
• extracting the security-related information, encrypted using the particular key, using the session key-associated information included in the recovery request message;
• encrypting the security-related information, encrypted by the particular key, using the recovery key;
• and
• transmitting the security-related information encrypted using the recovery key to the target server.

A method of managing security-related information in a DCAS, the method comprising:

• receiving a request for storage of security-related information for an authenticated SM from an AP server;
• receiving a first recovery request message including identification information of the AP server and identification information of the authenticated SM;
• and
• querying a previously prepared database to extract the security-related information.