Biblio

Propagation delay in blockchain networks is a major impairment of message transmission and validation in the bitcoin network. The transaction delay caused by message propagation across long network chains can cause significant threats to the bitcoin network integrity by allowing miners to find blocks during the message consensus process. Potential threats of slow transaction dissemination include double-spending, partitions, and eclipse attacks. In this paper, we propose a method for minimizing propagation delay by reducing non-compulsory message broadcasts during transaction dissemination in the underlying blockchain network. Our method will decrease the propagation delay in the bitcoin network and consequently mitigate the security threats based on message dissemination delay. Our results show improvement in the delay time with more effect on networks with a large number of nodes.

This paper proposes a proximity-aware extensions to the current Bitcoin protocol, named Master Node Based Clustering (MNBC). The ultimate purpose of the proposed protocol is to evaluate the security and performance of grouping nodes based on physical proximity. In MNBC protocol, physical internet connectivity increases as well as the number of hops between nodes decreases through assigning nodes to be responsible for propagating based on physical internet proximity.

Globalization of IC manufacturing has led to increased security concerns, notably IP theft. Several logic locking techniques have been developed for protecting designs, but they typically display very large overhead, and are generally susceptible to deciphering attacks. In this paper, we propose latch-based logic locking, which manipulates both the flow of data and logic in the design. This method converts an interconnected subset of existing flip-flops to pairs of latches with programmable phase. In tandem, decoy latches and logic are added, inhibiting an attacker from determining the actual design functionality. To validate this technique, we developed and verified a locking insertion flow, analyzed PPA and ATPG overhead on benchmark circuits and industry cores, extended existing attacks to account for the technique, and taped out a demonstration chip. Importantly, we show that the design overhead with this approach is significantly less than with previous logic locking schemes, while resisting model checker-based, oracle-driven attacks. With minimal delay overhead, large numbers of decoy latches can be added, cheaply increasing attack resistance.

The position information leakage of under-water sensor networks has been widely concerned. However, the underwater environment has unique characteristics compared with the terrestrial environment, for example, the asynchronous clock, stratification compensation. Therefore, the privacy preserving localization algorithm for terrestrial is not suitable. At present, the proposed privacy preserving localization algorithm is at the cost of reducing the localization accuracy and increasing the complexity of the algorithm. In this paper, a privacy preserving localization algorithm for underwater sensor networks with ray compensation is proposed. Besides, the localization algorithm we designed hides the position information of anchor nodes, and eliminates the influence of asynchronous clock. More importantly, the positioning accuracy is improved. Finally, the simulation results show that the location algorithm with privacy preserving and without privacy preserving have the same location accuracy. In addition, the algorithm proposed in this paper greatly improves the positioning accuracy compared with the existing work.

The mechanism of peers randomly choosing logical neighbors without any knowledge about underlying physical topology can cause a delay overhead in information propagation which makes the system vulnerable to double spend attacks. This paper introduces a proximity-aware extensions to the current Bitcoin protocol, named Master Node Based Clustering (MNBC). The ultimate purpose of the proposed protocol is to improve the information propagation delay in the Bitcoin network.

As the ocean covers 70% of the Earth's surface, it becomes inevitable to develop or extend underwater applications. Compared to Visible Light medium, Acoustic medium has been widely used to transmit the data from source to destination in underwater communication. Data transmission, however, has the limitation such as propagation delay, reliability, power constraints, etc. Although underwater MAC protocols have been developed to overcome these challenges, there are still some drawbacks due to the harsh underwater environment. Therefore, the selection mechanism for underwater multi-media communication is proposed inside Medium Access Control (MAC) layer. In this paper, the main focus is to select the appropriate medium based on the distance between nodes and transmission power. The result of performance evaluation shows that this multimedia approach can complement the existing underwater single medium communication. As a result, underwater multimedia mechanism increases the reliability and energy efficiency in data transmission.