DS-CKDSE: A Dual-Server Conjunctive Keyword Dynamic Searchable Encryption with Forward and Backward Security.

Area of Science:

• Computer Science
• Cryptography
• Cloud Security

Background:

• Dynamic Searchable Encryption (DSE) is crucial for secure cloud data searching.
• Existing single-server DSE schemes suffer from Keyword Pair Result Pattern (KPRP) leakage and lack simultaneous forward/backward security.

Purpose of the Study:

• To propose a novel dual-server conjunctive keyword DSE scheme (DS-CKDSE).
• To address KPRP leakage and achieve robust forward and backward security.
• To support efficient conjunctive queries over encrypted data.

Main Methods:

• A dual-server architecture is employed.
• A secure index is constructed using a full binary tree and an Indistinguishable Bloom Filter (IBF).
• Random state updates, dual-state arrays, and timestamp trapdoors ensure security and functionality.

Main Results:

• The DS-CKDSE scheme mitigates KPRP leakage by separating index storage and trapdoor verification.
• The scheme satisfies adaptive security under a defined leakage function.
• Experimental results demonstrate high efficiency in update and search operations.

Conclusions:

• The proposed dual-server DSE scheme effectively enhances security and efficiency for confidential cloud data searching.
• It provides a robust solution against known leakage attacks while maintaining performance.