The authors for a long time have investigated the phenomenon of global synchronization. Specifically, the occur- rence of a self-oscillatory regime in a control system was investigated. The model was built for the interaction of the TCP protocol and the active queue management algorithm RED. As a result of the research, the authors identified a set of methods for constructing the model, studying the model structure, calculating parameters of self-oscillations and verifying theoretical results based on a computer simulation. The paper summarizes the main results, obtained by the authors, and gives the description of their approaches.