Application of the timed automata abstraction to the performance evaluation of the architecture of a bank on- line transaction processing system

Timed automata is an abstraction that can provide a way of expressing timing delays when the behavior of a real time system is modeled. Then, for the verification of specifications and properties of the system model checking techniques can be used. In this work an attempt is made to model an on-line transaction processing system with timed automata. We describe a bank that has multiple branches with multiple tellers at each branch. The transactions represent the deposit or the withdrawal that a customer makes. Basically, it is the database management system of the bank information system that is modeled and its time response to various different scenarios of customer arrival rates at each teller machine is assessed as well as the transactions throughput that can be served at specific timing windows. Scenarios are based on dynamically increasing and decreasing of the on-going transactions per branch at a specified period of time. The operation of the considered information system generates different types of concurrent processes which are modeled by forming a multitude of timed automata communicating and synchronized between each other with channel variables. The system is modeled and verified using the real time model checker UPPAAL that provides the possibility to check our model for atomicity, consistency and durability. The results of this analysis and the experience in developing, simulating and verifying this model are presented and thoroughly discussed. M. Kourkouli, G. Hassapis, "Application of the timed automata abstraction to the performance evaluation of the architecture of a bank on-line transaction processing system", Proceedings of the 2nd South-East European Workshop on Formal Methods (SEEFM05), Ohrid, 18-19 Nov 2005, pp. 142-153. 142