The article analyses the possibilities and techniques of modeling global cyber-attacks on an internetwork of small countries. The authors study the Distributed Denial of Service (DDoS) attack against Estonian internetwork, which took place in 2007, in an open-source Nessi2 simulator environment, as DDoS appears to be the most common type of informational attack on resources used todeay. Such a modeling can be replicated with a certain degree of accuracy because the most of powerful attacks have been relatively well-documented. The article covers the most lifelike attack scenarios accomplished by sophisticated modeling of underlying traffic cases. Conclusions drawn from the simulation show that even large-scale DDoS attacks can be successfully modeled using limited resources only. Future research directions, motivated by the research, underlying this article, are highlighted at the end.