Key Shard Verification Using Challenge Responses Against Device Substitution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Physical key devices are susceptible to interception and substitution by unauthorized entities, leading to unauthorized access and compromised security, especially when sharded keys cannot be verified without complete shard collection.
Innovation Solution
A set of batteryless security devices, each storing a shared encryption key and unique authentication key, perform cryptographic verification using challenge responses to confirm key registration, even when not all shards are available.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If key sharding is used to improve security, then key safety is improved, but key verification becomes impossible without complete shard collection
Solution Approach 1:
The private key is divided into multiple key shards distributed across different devices. Each device holds a portion of the key, and no single device has the complete key. This segmentation prevents unauthorized access while enabling verification when sufficient shards are collected.
Solution Approach 2:
A verification server acts as an intermediary between the key shards and the verification process. The server receives challenge requests from authentication servers, coordinates the collection of key shards, and manages the verification process. This intermediary enables verification without requiring direct possession of the complete key.
2Reliability
If physical key devices are used for authentication, then authentication security is improved, but device interception and substitution become more feasible
Solution Approach 1:
The authentication key is divided into multiple key shards that are physically distributed across different key storage devices. To compromise the authentication, an attacker would need to intercept and substitute multiple devices simultaneously, which is significantly more difficult than substituting a single device.
Solution Approach 2:
The system performs preliminary verification by challenging the authentication server to prove it possesses the complete key before allowing access. This preliminary action prevents substitution attacks by verifying the authenticity of the key material before it is used for authentication.
3Ease of operation
If conventional key verification operations are used, then verification simplicity is maintained, but verification fails when shards are incomplete
Solution Approach 1:
The verification process is dynamic and adaptive. The system determines how many key shards are required for verification based on the threshold parameter, and the verification server dynamically collects and validates the necessary shards. This dynamic approach maintains simplicity for the user while ensuring reliable verification.
Data Source
AI summary
In certain embodiments, verification operations are performed. A first device packaged with a second device may store a first key shard and a second key. The first key shard may be a same key shard as a corresponding key shard stored on the second device, where the second key is different from a corresponding key stored on the second device. Additionally, the first key shard and the corresponding key shard are associated with a user. In connection with a request from a web service, the first device or a computing device may generate a response to the request using the second key by identifying the second key using an identifier of the request. Furthermore, the first device or the computing device may send the response to the web service, where the web service confirms registration of the first key shard based on the response.