Applying Queuing Models for Assessing Network Services Dependability Parameters in Modern Information Systems

Due to the continuous growth of Internet users, computer systems become more powerful to follow still rising needs. Modern structures so-called Information Systems encompass not only more reliable hardware, but first of all multifunctional and thus highly compound software. On one hand, this gives great opportunity to realize very complex tasks through a network, even such as commercial business services. On the other hand, this introduces many issues with dependability of such systems that management and control of these infrastructures becomes extremely hard. Adapting well-studied knowledge on systems dependability to the new circumstances, we emphasize role of performance as one of dependability properties. Our response for requirements of efficient means for optimization and forecasting of Information Systems is to revitalize queuing models concept and combine them with computer simulation techniques in order to obtain scalable, fast and detailed enough analysis methodology.