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Cyberattacks have been progressed in the fields of Internet of Things, and artificial intelligence technologies using the advanced persistent threat (APT) method recently. The damage caused by ransomware is rapidly spreading among APT attacks, and the range of the damages of individuals, corporations, public institutions, and even governments are increasing. The seriousness of the problem has increased because ransomware has been evolving into an intelligent ransomware attack that spreads over the network to infect multiple users simultaneously. This study used open source endpoint detection and response tools to build and test a framework environment that enables systematic ransomware detection at the network and system level. Experimental results demonstrate that the use of EDR tools can quickly extract ransomware attack features and respond to attacks.

In this work, a 2-by-2 array of a low-profile EBG ground plane is used as a means of sustaining the radiation performance of a 900-MHz LoRa antenna that could be installed at various construction sites. The proposed semi-circles added mushroom (SAM) structure enables a thin EBG height of 0.02λg on an FR-4 substrate at 900 MHz frequencies. A planar electric meander antenna for the 900-MHz LoRa band is integrated with the proposed 2-by-2 SAM plane. From a simulation and demonstration, it is found that the impedance and radiation properties of the integrated prototype in free space are well maintained with a minimum degradation even when it is placed on a concrete medium.

IEEE 802.15.4 is the global standard protocol designed for low-power and low-rate wireless personal area networks. When applied to sensor networks, extra care should be taken due to their requirements for multihop communication with minimum energy consumption. In this article we first discuss potential problems with the energy consumption in sensor networks using IEEE 802.15.4. Then six representative categories of algorithms are presented. The algorithms reside in between the MAC and a network layer. All operations of the MAC are performed through the standard interfaces of IEEE 802.15.4 without altering the standard protocol. The energy consumption and latency of the algorithms are evaluated by analysis and experiments, and the feasibility of real implementations is also discussed.

A 32-year-old male patient, diagnosed as a hepatic solitary angiomyolipoma post-operatively, is reported. The tumor was well definedly inhomogenous fat density mass on ultrasonography, computerized tomography (CT) and magnetic resonance imaging (MRI). The lesion was hypervascular on arteriography. The diagnosis was confirmed by an extended right lobectomy and histological examination.

In short range and low-rate wireless networks, energy saving has been one of the hottest issues. Compared to high-rate networks designed for multi-media data streaming, the low-rate networks mainly focus on monitoring and control applications. In most of the applications, nodes are expected to operate on battery. For saving energy in those types of networks, medium access control (MAC) protocols have been considered as one of the most essential and actively researched areas. In this chapter, we investigate the energy saving MAC issues and protocols of short range and low rate wireless networks.

In this paper, we propose an adaptive frequency hopping algorithm, entitled robust adaptive frequency hopping (RAFH), for increased reliability of wireless medical telemetry system (WMTS) under coexistence environment with non-medical devices. The conventional adaptive frequency hopping (AFH) scheme classifies channels into "good" or "bad" according to the threshold-based on-off decision, and uses good channels with a uniform hop probability. Unlike the conventional AFH scheme, RAFH solves a constrained entropy maximization problem and assigns each channel a different hop probability, which is a decreasing function of the measured PER. By adopting constrained entropy maximization, RAFH not only improves the average PER, but also reduces the PER fluctuation under dynamic interference environment. Our simulation studies show that RAFH outperforms the basic FH and the conventional AFH with respect to the PER under various scenarios of dynamic interference.

This paper focus on the testbed experimentation of a meshed tree routing algorithm with local link state for wireless personal area networks (WPANs) based on current IEEE 802.15.4 MAC and PHY. The meshed tree uses a block addressing scheme based on tree structure and local link state information for mesh routing. Our approach exploits the information from the global tree structure for the direction of packet forwarding and local link state for choosing the next hop toward the destination. It has two prominent features: scalability and fault tolerance. Each node maintains a local link state of k-hop(usually 2-hop) information regardless of network size, which makes the approach scalable. Being a mesh, our approach shows good fault tolerance and load balancing. Testbed experiments show that the meshed tree displays superior performance when compared with AODV and a tree based algorithm. Comparisons were made with respect to packet deliver ratio, energy consumption and memory usage. The proposed algorithm is being considered as the routing algorithm for IEEE 802.15.5 WPANMesh standard.

In wireless sensor networks, a periodic broadcast message or a beacon with strict time requirement can be con- tinuously collided when there are multiple nodes with the same period in the same space. This type of collision prevents a network from operating normally: a node is unable to join a network, and a network topology breaks if the periodic message contains critical information such as network and timing parameters as in IEEE 802.15.4. We show that the affected area by the collision occupies significant percentage of an original service area. This paper proposes a new algorithm to solve the permanent collision problem in periodic broadcasting or beaconing. The proposed stochastic beacon algorithm avoids the collision by incorporating randomness in beacon transmission while main- taining a fixed beacon period. The algorithm is evaluated by analysis and simulation based on IEEE 802.15.4, and compared with other 7 methods. The results show that our algorithm can avoid permanent beacon collision and reduces substantially the collision probability with very low added complexity.

In this paper, a new method, named adjustable timer resolution (ATR) is proposed to control tasks in a timely manner, with enhanced performance on real-time operating systems. It prevents useless execution of the timer interrupt service routine (ISR). Features of the proposed method are compared with the conventional method, and the schedulability is analyzed to estimate the performance. As an implementation model, uC/OS-II is modified and ported to a power PC processor system. The metrics and results of the model are presented and discussed.