Secret Handshakes from CA-Oblivious Encryption

Secret handshakes were recently introduced [BDS+ 03] to allow members of the same group to authenticate each other secretly, in the sense that someone who is not a group member cannot tell, by engaging some party in the handshake protocol, whether that party is a member of this group. On the other hand, any two parties who are members of the same group will recognize each other as members. Thus, a secret handshake protocol can be used in any scenario where group members need to identify each other without revealing their group affiliations to outsiders. The work of [BDS+ 03] constructed secret handshakes secure under the Bilinear Diffie-Hellman (BDH) assumption in the Random Oracle Model (ROM). We show how to build secret handshake protocols secure under a more standard cryptographic assumption of Computational Diffie Hellman (CDH), using a novel tool of CA-oblivious public key encryption, which is an encryption scheme s.t. neither the public key nor the ciphertext reveal any informat...

• Type: Conference
• Year: 2004
• Where: ASIACRYPT
• Authors: Claude Castelluccia, Stanislaw Jarecki, Gene Tsudik
• Keywords: ASIACRYPT 2004, Cryptology, Handshake Protocols, Secret Handshake, Secret Handshake Protocols