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Telecommunications profoundly impacts all major aspects of our everyday life. As a consequence, student instruction typically includes a series of specialized courses, each addressing a distinct telecommunication area, separating wireless from fixed (optical) communications. This creates the problem of knowledge fragmentation, hindering the student's perception of the topic since, at the service level, the applications and services offered to the users seem "virtually" independent from the underlying infrastructure. In this paper, to address this problem, we designed, analyzed, and implemented a 6 h course module on the five generations of wireless and fixed networks, which was presented as an integral part of the undergraduate course "Broadband Communications", which was offered at the Dept. of Electrical and Electronic Engineering, School of Pedagogical and Technological Education (ASPETE), Athens, Greece. The main targets of this module are the following. Firstly, it aims to familiarize students with the fixed generations taxonomy, defined by the ETSI Industry Specification Group (ISG) F5G. This taxonomy serves as a foundation for understanding the evolution of telecommunications technologies. Secondly, the module seeks to integrate the acquired knowledge of the students in their previous telecommunication-related courses. During their curriculum, this knowledge was divided into two separate parts: wireless and fixed (optical). By coupling these two areas, students can develop a deeper understanding of the field. Lastly, the module aims to explore cutting-edge technologies and advancements in the telecommunications industry. In this way, it prepares students to enter the professional world during the fifth-generation era. Additionally, it provides them with valuable insights into the ongoing research and development in the field of 6G. Overall, this module serves as a comprehensive platform for students to enhance their understanding of telecommunications, from the foundational concepts to the latest advancements. To evaluate the impact of this module, the students were asked to fill out a questionnaire that included seven questions upon module completion. This questionnaire was completed successfully by 32 students in the previous academic year and by 16 students in this academic year. Moreover, a 20-question multiple choice quiz was offered to the students, allowing us to probe more into the typical errors and misconceptions about the topic. [ABSTRACT FROM AUTHOR]

In recent years, we have been experiencing fast proliferation of different types of ransomware targeting home users, companies and even critical telecommunications infrastructure elements. Modern day ransomware relies on sophisticated infection, persistence and recovery prevention mechanisms. Some recent examples that received significant attention include WannaCry, Petya and BadRabbit. To design and develop appropriate defense mechanisms, it is important to understand the characteristics and the behavior of different types of ransomware. Dynamic analysis techniques are typically used to achieve that purpose, where the malicious binaries are executed in a controlled environment and are then observed. In this work, the dynamic analysis results focusing on the infamous WannaCry ransomware are presented. In particular, WannaCry is examined, during its execution in a purpose-built virtual lab environment, in order to analyze its infection, persistence, recovery prevention and propagation mechanisms. The results obtained may be used for developing appropriate detection and defense solutions for WannaCry and other ransomware families that exhibit similar behaviors. [ABSTRACT FROM AUTHOR]

The authors study and evaluate a mobility‐aware call admission control algorithm in a mobile hotspot. More specifically, a vehicle which has an access point of a fixed capacity and may alternate between stop and moving phases is considered. In the stop phase, the vehicle services new and handover calls. To prioritise handover calls a probabilistic bandwidth reservation policy is considered where a fraction of the capacity is reserved for handover calls. Based on this policy, new calls may enter the reservation space with a predefined probability. In addition, handover calls have the option to wait in a queue of finite size if there are no available resources at the time of their arrival. In the moving phase, the vehicle services only new calls under the classical complete sharing policy. In both phases, calls arrive in the system according to a quasi‐random process, require a single bandwidth unit for their acceptance in the system and have an exponentially distributed service time. To analytically determine the various performance measures, such as time congestion probabilities, call blocking probabilities and link utilisation, an accurate analytical method is presented based on three‐dimensional Markov chains. [ABSTRACT FROM AUTHOR]