Broadcast Encryption Differential Ciphertext Generation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional broadcast encryption schemes are inefficient in reusing previous computation results during cryptography header generation and decryption, leading to performance degradation when the subscriber set changes, and they cannot accommodate an increasing number of content receiving clients.
Innovation Solution
The proposed solution involves differential ciphertext generation for optimized cryptography header generation and the use of a wide window point addition method for faster decryption, along with a clustering solution to expand the system's capacity and handle an unlimited client population.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional broadcast encryption schemes are used for cryptography header generation and decryption, then security and access control are maintained, but computation time increases and performance degrades when the subscriber set changes
Solution Approach 1:
The patent pre-computes and stores computation results (such as cryptographic headers and decryption keys) before they are needed. When the subscriber set changes, the system retrieves and reuses these pre-computed results rather than recalculating them from scratch, significantly reducing computation time while maintaining security.
Solution Approach 2:
The patent modifies cryptographic parameters and computation methods to enable efficient reuse of previous computation results. By changing how cryptographic headers are generated and how decryption keys are reconstructed, the system maintains security requirements while reducing the computational burden when subscriber sets change.
2Quantity of substance
If traditional broadcast encryption schemes are used, then the system can handle a fixed number of clients, but the system cannot accommodate an increasing number of content receiving clients
Solution Approach 1:
The patent implements a dynamic system where the subscriber set can change over time without requiring complete re-computation. The system adapts to an increasing number of clients by efficiently updating cryptographic parameters and reusing previous computation results, enabling scalability while maintaining security.
Solution Approach 2:
The patent creates a universal cryptographic framework that can handle variable subscriber sets of any size. The system uses generalized cryptographic parameters and computation methods that work for both small and large numbers of clients, eliminating the limitation of fixed client counts in traditional schemes.
3Reliability
If traditional broadcast encryption schemes are used for cryptography header generation, then security is maintained, but the amount of computation increases when the subscriber set changes
Solution Approach 1:
The patent selectively discards computation results that are no longer needed and recovers/reuses valid previous computation results when generating new cryptographic headers. This approach maintains security by validating reused results while avoiding redundant computation, significantly improving efficiency when subscriber sets change incrementally.
Data Source
AI summary
A content distribution method with broadcast encryption, comprising an encryption process that includes the computation of a ciphertext using a differential ciphertext generation method. The ciphertext needs to be recomputed whenever the subscriber set changes. The differential ciphertext generation method computes the new ciphertext by reusing previously preserved computational results of a previous ciphertext, thereby improving the efficiency of the system. A content distribution method with broadcast encryption also comprises a decryption process that includes the reconstruction of the encryption secret that is used for decrypting the encrypted content. A wide window point addition method is used in the encryption secret reconstruction. The wide window point addition method reuses previously preserved computational results of group-divided point additions of public parameters, thereby improving the efficiency of the system. A clustering solution with multiple instances of key server and entitlement server allows the expansion of user population in the content distribution network.