A Simulation Model of the Confrontation between an Organized Attacker and an Information Security System in the Implementation of an Attack on a Network Management System of Clock Network Synchronization

This article provides an overview of the interaction between the warring parties and the main stages of the confrontation between the organized attacker and the information security system in the implementation of an attack on the network management system of clock network synchronization. A simulation model has been developed that reflects all stages of the struggle, which allows, depending on the resources of an organized attacker and the information security system, to obtain probabilistic and temporal characteristics of the results of the confrontation. Simulation has been carried out for various scenarios of organizing an attack at all stages of the confrontation, from the overwhelming advantage of an organized malefactor to the overwhelming advantage of an information security system. The results obtained in the general case can be used by security administrators and network administrators to make adjustments to the strategy of organizing the protection of the network management system of clock network synchronization.

Entropic model of network dynamics of clocking network synchronization

The main task of the clocking network synchronization (CNS) network subsystem is the formation, transmission, distribution and delivery of synchronization signals to the telecommunication system (TCS) digital equipment for the purpose of its coordinated interaction. Indicators of the telecommunication services quality are inextricably linked with the indicators of the CNS network functioning quality, in this regard, the process of monitoring and managing the CNS network comes to the fore for the purpose of prompt detection of failures and their subsequent elimination. The article provides an overview of the main classes of CNS network equipment and their diagnostic parameters, and also indicates the significant influence of the CNS network functioning process on the entire TCS functioning. To assess the technical condition of the CNS network an approach using the entropy analysis of the diagnostic parameters of the CNS network elements is proposed. The entropy model of the network dynamics is obtained in CNS work, which can later be used to develop a methodology for monitoring the technical condition of the CNS network. Using this model, it is possible to estimate not only the differential entropy of each CNS network element, but also to estimate the differential entropy of the entire CNS network or a separate fragment of the CNS network. Differential entropy parameters reflect the technical state of the CNS network.

A METHOD FOR ELIMINATING LOOPS IN A CLOCK SYNCHRONIZATION NETWORK

Рассмотрены вопросы организации тактовой сетевой синхронизации (ТСС) в сетях пятого поколения. Предложен новый метод обнаружения и устранения петель в сети ТСС на основе определения компонент связности графа и анализа матрицы циклов графа сети синхронизации, оценена эффективность его использования. Основным математическим аппаратом, используемым для описания предложенного метода, является теория графов и матриц. The article discusses the issues of the organization of clock network synchronization in 5G networks. A new method of detecting and eliminating loops in a synchronization network basedondeterminingthecomponentsofthegraphconnectivity and analyzing the graph cycle matrix of a synchronization network is proposed, and the efficiency of its utilization is estimated. The main mathematical apparatus used to describe the proposed method is the theory of graphs and matrices.

Locus Coeruleus Degeneration Correlated with Levodopa Resistance in Parkinson’s Disease: A Retrospective Analysis

Background: The widely divergent responsiveness of Parkinson’s disease (PD) patients to levodopa is an important clinical issue because of its relationship with quality of life and disease prognosis. Preliminary animal experiments have suggested that degeneration of the locus coeruleus (LC) attenuates the efficacy of levodopa treatment. Objective: To explore the relationship between LC degeneration and levodopa responsiveness in PD patients in vivo. Methods: Neuromelanin-sensitive magnetic resonance imaging (NM-MRI), a good indicator of LC and substantia nigra (SN) degeneration, and levodopa challenge tests were conducted in 57 PD patients. Responsiveness to levodopa was evaluated by the rates of change of the Unified Parkinson’s Disease Rating Scale Part III score and somatomotor network synchronization calculated from resting-state functional MRI before and after levodopa administration. Next, we assessed the relationship between the contrast-to-noise ratio of LC (CNRLC) and levodopa responsiveness. Multiple linear regression analysis was conducted to rule out the potential influence of SN degeneration on levodopa responsiveness. Results: A significant positive correlation was found between CNRLC and the motor improvement after levodopa administration (R = 0.421, p = 0.004). CNRLC also correlated with improvement in somatomotor network synchronization (R = –0.323, p = 0.029). Furthermore, the relationship between CNRLC and levodopa responsiveness was independent of SN degeneration. Conclusion: LC degeneration might be an essential factor for levodopa resistance. LC evaluation using NM-MRI might be an alternative tool for predicting levodopa responsiveness and for helping to stratify patients into clinical trials aimed at improving the efficacy of levodopa.