A New ID-Based Key Sharing System

Shigeo Tsujii

Xueyan Liu, Qiang ZHANG, Caifen Wang

Yun Wei, Fushan Wei, Chuangui Ma

Non-interactive key exchange (NIKE) allows two parties to establish a shared key without communications. In ID-based non-interactive key exchange (ID-NIKE) protocols, private key generator (PKG) knows user's private key, so it can calculate the shared key between two participants, and most constructions of ID-NIKE need expensive pairing operation. To overcome these disadvantages, a security model of certificateless non-interactive key exchange (CL-NIKE) is proposed in this paper. And a scheme without pairings is also given. The proposed protocol is proved secure in the Random Oracle Model (ROM) based on the gap Diffie-Hellman (GDH) and computational Diffie-Hellman (CDH) problem. In the new protocol, key generation center (KGC) only knows user's partial key and is not able to calculate the shared key. Moreover, the new protocol is more efficient than the existing ID-NIKE schemes because it is pairing-free.

Hyunjue Kim, Nam Junghyun, Kim Seungjoo +1 more

A group key agreement protocol allows a group of user to share a key which may later be used to achieve certain cryptographic goals. In this paper, we propose a new scalable two-round ID-based group key agreement protocol which would be well fit to a Pay-TV system, additionally. to the fields of internet stock quotes, audio and music deliveries, software updates and the like. Our protocol improves the three round poop key agreement protocol of Nam et al., resulting in upgrading the computational efficiency by using the batch verification technique in pairing-based cryptography. Also our protocol simplifies the key agreement procedures by utilizing ID-based system. We prove the security of our protocol under the Computational Diffie-Hellman assumption and the Bilinear Decisional Diffie-Hellman assumption. Also we analyze its efficiency.

Hatsukazu Tanaka

Caifen Wang

Authenticated key agreement protocol allows a group of users in an open network environment to identify each other and share a security session key.This article proposed a new scheme of ID-based authenticated multi-party key agreement based on McCullagh-Barreto scheme.Key seed was introduced to update temporary public/private key pairs.The new scheme is able to realize the authentication,improve the security,resist Reveal query attack and the key compromise impersonation attack successfully,and it has many properties such as non-key control and equal contribution.