Search

With the widespread application of Internet of things (IoT), the interference problem becomes more and more serious, which results in not only the poor network performance but also the increased energy consumption of IoT nodes. Therefore, in this paper, we investigate the problem of how to locate the interference sources and infer their communication relationships in the cognitive radio IoT (CR-IoT) deployment scenario. First, we utilize MDS-MAP(P) algorithm with dynamic power control to realize cooperative self-localization of the CR-IoT nodes, which is more energy-efficient than all the IoT nodes equipped with global positioning system (GPS) receivers. Then, we propose a non-cooperative localization method to determine the inference sources with the angle of arrivals (AoAs) measured by the CR-IoT nodes. Finally, the communication relationship between interference sources can be inferred based on the association rule of signals. The network simulation results validate that the proposed methods can locate the interference sources accurately with low energy consumption and correctly infer their communication relationships, which is helpful for the interrupted CR-IoT nodes to take a specific opportunistic transmission policy to reduce their energy consumption.

MIFARE CLASSIC CARD (hereinafter referred to as Mifare Classic) produced by NXP is the most common contactless smartcard on the market. Mifare Classics uses NXP's licensed patent stream cipher algorithm, CRYPTO-1, whose internal structure and algorithm parameters are commercial secrets and unknown to the outside world. At present, there is much research on the security of Mifare Classics. We analyze the security of the CRYPTO-1 algorithm in the Mifare Classics from the point of generating function of the linear feedback shift register (Linear feedback shift register, hereinafter referred to as LFSR) of the card and propose an optimization method for the vulnerability of generating function to improve the security of the Mifare Classics. Furthermore, the optimization method is generally applicable to the encryption algorithm based on the LFSR generating of pseudo-random sequences.

Identifying critical nodes from the point of view that destructiveness equals to criticality, the traditional identification methods usually consider the degree of damage but does not analyze the type of damage. The critical nodes identified have a certain universality, but the pertinence is not strong. In this paper, a critical node identification method based on the analysis of network partition for Ad Hoc network is proposed. Firstly, the Kernighan-Lin algorithm is applied to group the nodes in the network, and then the boundary nodes between different groups are selected from the grouping results. Finally, the boundary nodes are re-screened by combining the node’s degree value to select the nodes that can lead to the partition of the network. The experimental results show that the failure of identified critical nodes can directly lead to network partitioned into multiple subnets, destroy the connectivity of the network seriously.

In this paper, we propose a practical image encryption algorithm for privacy protection and analyze its security. This algorithm will generate a permutation on the pixels of the image and need not share a permutation list for the sender and receiver anymore. The parameters of the algorithm are correlative to the size of the image and can be generated with the image. The image encryption algorithm is suitable for image outsourcing on cloud computing platform, image secret transmission in Wireless Sensor Network (WSN) and image transmission in Unmanned Aerial Vehicle (UAV) photography.

In this paper, we propose a secret sharing scheme based on Hadamard matrix and prove its security properties. This secret sharing scheme enjoys both the lower computation complexity and the lower space complexity. This secret sharing scheme can be widely used in many light-weight computation and storage devices, such as smart phones, sensors in Internet of things.

In this paper, we explore a linear secret sharing scheme based with multiple prime muduli, explore the security properties and assess the computation and space complexity. This novel secret sharing scheme enjoys both the lower computation complexity and the lower space complexity than previous schemes, which can be widely used in light-weight computation and storage devices, such as smart phones, sensors in Internet of things.