Modern network centric information systems implement highly distributed architectures that usually include multiple application servers. Application design is mainly based on the fundamental object-oriented principles and the adopted architecture matches the logical decomposition of applications (into several tiers like presentation, logic and data) to their software and hardware structuring. The provided recovery solutions ensure an at-mostonce service request processing by an existing transaction processing infrastructure. However, in published works performance evaluation of transaction processing aspects is focused on the computational model of database servers. Also, there are no available tools which enable exploring the performance and availability trade-offs that arise when applying different combinations of concurrency control, atomic commit and recovery protocols. This paper introduces ACID Sim Tools, a publicly available tool and at the same time an open source framework for interactive and batch-mode simulation of transaction processing architectures that adopt the basic assumptions of an object-based computational model.