Scholarlink

The double ratchet algorithm, widely used in secure messaging systems like Signal and WhatsApp, ensures forward secrecy and robust key management. This paper proposes two enhancements to strengthen its security and efficiency. First, pre-shared keys (PSKs) are introduced during initialization to improve entropy and defend against active attacks such as state injection and desynchronization. Second, a comparative analysis of SHA-256, BLAKE2s, and BLAKE3 is conducted to evaluate their performance as key derivation functions (KDFs) within the algorithm. Results show that BLAKE3 achieves a strong balance between speed and security. The improved design reduces computational overhead and enhances resilience, making it suitable for resource-limited and latency-sensitive applications.

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Enhancing Double Ratchet Algorithm with Pre-Shared Key Mechanism and Optimal KDF Selection

  • 会议论文

  • 发表日期：

    2026年

查看全文
  • Yutong Chu,
  • Shijia Hong,
  • Huijie Yang,
  • Tianqi Zhou

摘要

The double ratchet algorithm, widely used in secure messaging systems like Signal and WhatsApp, ensures forward secrecy and robust key management. This paper proposes two enhancements to strengthen its security and efficiency. First, pre-shared keys (PSKs) are introduced during initialization to improve entropy and defend against active attacks such as state injection and desynchronization. Second, a comparative analysis of SHA-256, BLAKE2s, and BLAKE3 is conducted to evaluate their performance as key derivation functions (KDFs) within the algorithm. Results show that BLAKE3 achieves a strong balance between speed and security. The improved design reduces computational overhead and enhances resilience, making it suitable for resource-limited and latency-sensitive applications.