Secret Sharing for Secure Offline Digital Content Distribution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for secure distribution of digital information are vulnerable to hacking, especially in off-line scenarios where trusted security hardware is not available, and lack effective mechanisms for reporting and incentivizing honest client collaboration.
Innovation Solution
A method and system that utilize secret sharing techniques to distribute encrypted information, requiring clients to collaborate over a local communication link to decrypt content, with a server recording transactions and providing incentives for honest reporting, ensuring security and reducing revenue loss from unreported off-line purchases.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If secret sharing is used to distribute encrypted information to multiple clients, then security against hacking is improved, but device complexity increases due to the need for key-share management and collaboration protocols
Solution Approach 1:
The decryption key is segmented into multiple key-shares distributed to different clients. Each key-share is useless alone but combines to reconstruct the full decryption key, providing security without requiring complex trusted hardware in each device
Solution Approach 2:
A server acts as an intermediary to manage the secret sharing scheme. The server distributes key-shares, receives collaboration reports from clients, and coordinates the system operation, simplifying the complexity burden from individual devices to a centralized management system
2Reliability
If clients are required to collaborate locally to decrypt content, then security in off-line scenarios is improved, but ease of operation deteriorates due to the need for peer-to-peer key-share exchange
Solution Approach 1:
Clients autonomously perform local collaboration to exchange key-shares and reconstruct decryption keys without requiring continuous server connection. This enables secure off-line content access while maintaining operational simplicity through automated protocols
3Loss of energy
If a server records transactions based on client reports, then loss of revenue from unreported off-line purchases is reduced, but device complexity increases due to the reporting and verification mechanism
Solution Approach 1:
Clients provide feedback reports to the server about their collaboration and content access activities. The server uses this feedback to record transactions and verify compliance, reducing revenue loss through accountable tracking without requiring complex local enforcement mechanisms in client devices
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A method for distributing information includes distributing an item of encrypted information to a plurality of clients and distributing respective key- shares to the clients, such that each client will require a key-share that has been distributed to at least one other client in order to reconstruct a key for decrypting the encrypted information. Upon receiving from a first client a report that a second client requested and received a respective one of the key-shares from the first client, a record of a delivery of the item to the second client is made responsively to the report.