Oblivious Order-Preserving Encryption for Secure Cloud Database Queries
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Outsourced data stored in untrusted cloud databases loses order information upon encryption, hindering legitimate database operations like range queries and sorting, as encryption obscures the order, requiring decryption for these operations, which compromises data security and control.
Innovation Solution
Implementing an order-preserving encryption (OPE) tree that maintains the order of data through an OPE encoding system, allowing a data client to perform private order-based operations without revealing private information by using an oblivious comparison protocol and garbled circuits to traverse the OPE tree and determine OPE encodings for input values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If data is encrypted for secure storage in cloud databases, then data security is improved, but order information is lost and database operations like range queries and sorting cannot be performed
Solution Approach 1:
The patent introduces an intermediary OPE tree structure that mediates between the encrypted data storage and order-based query operations. The OPE tree maintains order information in an encrypted form, allowing the cloud service provider to perform range queries and sorting operations on ciphertext without decrypting them, thus resolving the contradiction between security and operability
Solution Approach 2:
The patent changes the parameter representation from plaintext to ciphertext while preserving order relationships through OPE encoding. By transforming data into ciphertext that maintains relative order (c1 < c2 iff p1 < p2), the system enables order-based operations on encrypted data, simultaneously achieving security and operational capability
2Object-affected harmful factors
If data is encrypted to prevent unauthorized access, then data protection is improved, but legitimate order-based operations require decryption which compromises security control
Solution Approach 1:
The OPE tree acts as an intermediary layer between the encrypted data and the query operations. It allows the cloud service provider to perform order-based operations directly on ciphertext without accessing plaintext, maintaining security control while enabling legitimate operations
Solution Approach 2:
The patent replaces the mechanical decryption process with an OPE-based system where order comparisons are performed directly on encrypted values. This substitution eliminates the need for decryption during query operations, preserving security control while enabling operations
3Ease of operation
If an OPE tree is implemented to preserve order, then order-based operations on encrypted data are enabled, but the system complexity increases
Solution Approach 1:
The patent segments the OPE tree into nodes with specific OPE encodings, allowing efficient traversal and query operations. This segmentation enables the cloud service provider to perform range queries by traversing only relevant portions of the tree, reducing the practical complexity despite the structured approach
Solution Approach 2:
The oblivious comparison protocol serves as an intermediary mechanism that simplifies the interaction between data owners and cloud service providers. It enables secure order comparisons without requiring complex cryptographic protocols or direct plaintext access, managing system complexity through a standardized interface
Data Source
AI summary
Methods, systems, and articles of manufacture are provided for oblivious order preserving encryption. A method may include: traversing, by a cloud service provider, an order preserving encryption (OPE) tree based on a result of an oblivious comparison performed by a data owner and a data client, the OPE tree having nodes that each correspond to a ciphertext of data associated with the data owner, the ciphertext of the data being stored at the cloud service provider, and a relative position of the nodes within the OPE tree corresponding to an order that is present in the data associated with the data owner; and determining, based on the traversing of the OPE tree, an OPE encoding for an input value from the data client, the OPE encoding for the input value indicative of a position of a node corresponding to the input value within the OPE tree.