Direct Chosen-Ciphertext-Attack hierarchical computing technique for identity-based encryption

作者：Zhang Leyou^*; Wu Qing; Hu Yupu

来源：ICIC Express Letters, 2013, 7(2): 571-576.

• Ciphertexts
• Computing techniques
• Diffie Hellman
• Direct CCA technique
• HIBE
• Hierarchical identity-based encryptions
• Identity Based Encryption
• Message authentication codes
• One-time signature
• Private key
• Provable security
• Standard model
• The standard model
• Transformation methods

In the previous works, the Chosen-Ciphertext-Attack (CCA) secure hierarchical identity-based encryption (HIBE) is always based on some transformation methods such as one-time signature and message authentication code (MAC). These methods result in the CCA schemes that are inefficient in the practice. To construct directly CCAsecure HIBE scheme is always a challenge at present. In this paper, a new direct CCA secure HIBE is proposed. The new scheme also has many advantages in the available, such as constant size ciphertexts, which is not relying on the hierarchy depth. In addition, the private keys in our system shrink as the identity depth increases. Under the standard model, the security of the new scheme is reduced to the hardness assumptiondecision bilinear Diffie-Hellman exponent problem (BDHE). This assumption is more natural than many of the hardness assumptions recently introduced to CCA HIBE in the standard model.

• 出版日期2013