Xiping Zhu

The security issue of WSNs based on cloud computing

The combination of WSNs and cloud computing actually does overcome the problems such as storage issues, real-time processing aporia, and ubiquitous accessibility challenge due to the low-power, small-size characteristics of WSNs. But there still exist some other issues, particularly security issues. In this paper, we present a pub/sub based framework of the combination paradigm, and we discuss about the advantages and disadvantages including the security challenges of the new paradigm. Finally, the solutions to security problem will be presented at last.

A P2P recommended trust nodes selection algorithm based on topological potential

Due to their open, distribution and anonymous nature, P2P systems are extremely susceptible to malicious users spreading harmful content. It is important to develop effective and efficient reputation based global trust model. This paper proposes a topological potential method derived from social network analysis to measure the recommendation degree of the recommended trust nodes by taken into account both the status and reputation. Having considered the reputation for each node and trust measurement between them, the method could appraise the integrated recommendation degree of P2P recommended trust nodes objectively. Thus, the goal to create the trust model is achieved by the help of selecting trust nodes effectively.

The performance of the MIMO physical layer security system with imperfect CSI

It is an important approach for achieving secure physical layer transmission using beamforming technology of multi-antenna, most of the transmission models are built on the perfect channel estimation model. The paper studies the secure physical layer transmission of multi-antenna beamforming with imperfect channel estimation information (CSI) and discusses the realization of the physical layer security in the actual communication environment with channel estimation error. We build a secure physical layer transmission model using beamforming technology of multi-antenna combined with SVD precoding technology, and we also prove the realization of the model with simulation under imperfect CSI.

Using Basis Expansion Model for Physical Layer Authentication in Time-Variant System

In this paper a physical layer authentication method is proposed to suit to time-variant wireless channels by taking advantage of the varied mutually orthogonal basis functions and the constant basis coefficients to approximate the state of separable paths, in which each sampling values of separable paths is related within a block transmission time in time-variant channels. Simulation experiments in orthogonal frequency division multiplexing (OFDM) system proves the validity of the novel authentication method. The novel method makes 2-4dB improvement compared to the physical-layer authentication using conventional Least Square (LS) channel sounding.

A novel detection scheme for malicious nodes in smart meter system

In this paper, we introduce a novel malicious nodes detection scheme in the smart meter system by the channel responses between nodes. By extraction the channel information of the different nodes and comparison them, the rough position of the nodes can be distinguished. When we detect the nodes located in the different position along with one ID or several nodes with different ID located in the same position, the malicious node attacks happened. The proposed schemes aim at achieving fast detection and minimizing the data transmission cost by taking advantage of temporal and spatial uniqueness in physical layer channel responses.