Аbdourahmane A. Optimization methods of content fragmentation process in peer-to-peer file-sharing networks

Object - file sharing process in decentralized flat overlay networks. The purpose - to increase content transmission quality and validity in file-sharing peer-to-peer networks. Subject - synthesis and analysis of fragmentation process in file-sharing peer-to-peer networks and methods to ensure the quality of service provision. Methods - methods of random process mathematical model; scheduling theory, dynamic programming theory methods; methods of analysis and synthesis of differential content downloading and uploading models. Results - a dynamic discrete-continuous model has been proposed for the first time for processes of downloaded files fragmentation, which allows taking into account significant differences in overlay dynamics, in fragments position, and in their delivery conditions; the task of optimizing the fragmentation process during files downloading using a dynamic discrete-continuous model is defined and solved, which allows ensuring smoothness and continuity of video content playback for the user; productivity analysis of established file replication algorithms was performed and it was demonstrated that the number of steps for a required resource search directly depends on the ratio of the total number of nodes to the total memory capacity available in the network for files storage; a method was developed to analyze peer downloading performance using different strategies in the form of normalized content download and upload speed ratio. Sphere of application - network telecommunication technologies engineering