Information Recording Device Controller Unique Key Generation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing content distribution systems face challenges in protecting digital content from unauthorized duplication and playback, as encryption methods can be compromised, leading to the creation of clone storage media and unauthorized use of content.
Innovation Solution
An information recording device with a data storage unit and controller that employs a public key cryptosystem, using a controller unique key to encrypt a medium device key and certificate, enabling secure authentication and key exchange processes to establish a secure channel for data communication, thereby preventing unauthorized access and duplication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional encryption methods are used to protect digital content, then content security is improved, but the system becomes vulnerable to cryptographic attacks and clone media creation
Solution Approach 1:
The encryption system is segmented into multiple independent components: content encryption keys are separated from decryption capabilities, and multiple key hierarchies (content keys, title keys, medium device keys) are implemented. This segmentation ensures that compromising one layer does not enable full decryption, thereby preventing clone media creation while maintaining content security.
Solution Approach 2:
A controller acts as an intermediary between the encrypted content and potential unauthorized devices. The controller manages key storage, performs authentication, and controls decryption operations. This intermediary layer prevents direct access to encryption keys, blocking cryptographic attacks and unauthorized playback while preserving legitimate content access.
2Reliability
If strong encryption and authentication mechanisms are implemented, then unauthorized access is prevented, but device complexity increases
Solution Approach 1:
Multiple security functions are merged into a single integrated controller: key generation, key storage, authentication verification, and decryption management are combined in one component. This merging reduces overall system complexity by eliminating the need for separate hardware modules for each function while maintaining strong security through the controller's coordinated execution of all security operations.
Data Source
AI summary
The data storage portion stores an encrypted medium device key Enc (Kcu, Kmd_i) generated by encrypting a medium device key (Kmd_i), a medium device key certificate (Certmedia), and encrypted content data generated by encrypting content data, the controller stores a controller key (Kc) and first controller identification information (IDcu), the information recording device being configured to execute, after being connected to an external host device, an one-way function calculation based on the controller key (Kc) and the first controller identification information (IDcu) to generate a controller unique key (Kcu) used when decrypting the encrypted medium device key Enc (Kcu, Kmd_i), and second controller identification information (IDcntr) used when decrypting the encrypted content data.