Low-Complexity Address Generation for Multiuser Detectors in IDMA Systems

This paper presents a low-complexity address generation unit (AGU) for multiuser detectors in interleave division multiple access (IDMA) systems. To this end, for the first time, all possible options for designing AGUs are first analyzed in detail. Subsequently, a complexity reduction technique is applied to each of those architectures. More specifically, some components in AGUs are relocated to make them shareable and removable without affecting the functionality. The complete transparency of such renovation makes it applicable to any existing multiuser detector without tailoring the interfacing components therein. Measuring the hardware complexity, all the resulting AGUs are compared with each other, and a new architecture simpler than the state-of-the-art one is developed. Implementation results in a 65 nm CMOS process, demonstrating that the proposed AGU can alleviate the equivalent gate count and the power consumption of the prior process by 13% and 31%, respectively.

A Small Subgroup Attack on Bitcoin Address Generation

We show how a small subgroup confinement-like attack may be mounted on the Bitcoin addresses generation protocol, by inspecting a special subgroup of the group associated to point multiplication. This approach does not undermine the system security but highlights the importance of using fair random sources during the private key selection.

Network dynamic defense system based on holographic transformation

Aimed at the problem of the boundary defense easily being out of availability caused by the static network structure, a novel dynamic enterprise network defense system based on holographic transformation is designed and implemented. To increase the uncertainty of network structure and the position of target nodes, the network view is dynamically changed by constantly transforming endpoint information. Virtual endpoint mutation and hopping period selection are achieved by the hopping address generation module. It takes the advantages of anti-collision and good randomicity of the Chinese national SM3 hash algorithm. The full-cycle hopping period is managed and controlled by the hopping period management mechanism based on the ciphertext policy attribute-based broadcast holographic transformation. Experiments show that the system achieves expected security goals and has good interactivity and high stability.