Identity-based verifiably committed signature scheme without random oracles

An identity-based verifiably committed signature scheme （IB-VCS） was proposed, which is proved secure in the standard model （i.e., without random oracles）. It enjoys the setup-free property and stand-alone property, both of which make an exchange protocol more practical. The scheme is unconditionally secure against the cheating signer, its security against the cheating verifier is reduced to the computational Diffie-Hellman （CDH） problem in the underlying group, it is secure against the cheating trusted third party if the underlying Paterson Schuldt＇s identity based signature （IBS） scheme is secure, which is proven true based on the CDH assumption in the standard model.     

A secure trust model for P2P systems based on trusted computing

Trust is one of the most important security requirements in the design and implementation of peer-to-peer （P2P） systems. In an environment where peers＇ identity privacy is important, it may conflict with trustworthiness that is based on the knowledge related to the peer＇s identity, while identity privacy is usually achieved by hiding such knowledge. A trust model based on trusted computing （TC） technology was proposed to enhance the identity privacy of peers during the trustworthiness evaluation process between peers from different groups. The simulation results show that, the model can be implemented in an efficient way, and when the degree of anonymity within group （DAWG） is up to 0.6 and the percentage of malicious peers is up to 70%7 the service selection failure rate is less than 0.15.     

Bi-slotted binary tree algorithm with stack for radio frequency identification tag anti-collision

A radio frequency identification (RFID) reader will fail to identify tags if a collision occurs. This paper proposes a bi-slotted binary tree algorithm (BSBTA) with stack for RFID tag anti-collision to improve the performance of binary tree algorithm (BTA). In BSBTA, the reader detects collisions by Manchester code and stores colliding prefixes in a stack. The query is composed of a two-bit prefix and an index value. Following every reader query, there are two timeslots for tags whose pointers and identities (IDs) match the query to respond, one for the tag whose next bit is 0 and the other for the tag with 1 as its next bit. Performance analysis and evaluation are also given. The time complexity and the communication complexity of BTA and BSBTA are derived. The simulation results compare the performance of BSBTA with several related anti-collision algorithms. It is shown that BSBTA outperforms BTA in terms of the average number of responded bits and timeslots for one tag identification.