The paper introduces a system model called the probabilistic asynchronous model which characterises the context in which many practical and the Internet-based applications are built. Specifically, the model regards that basic services and system components (e.g., network services) offer Quality of Service (QoS) guarantees that are probabilistic in nature, admitting that the guarantees may not be met on odd occasions within the remit of the stated probabilities. The model provides a basis for designing and reasoning about systems that adaptively meet QoS obligations to end users; eventual correctness need not be compromised when components fail in their QoS obligations.
Paul D. Ezhilchelvan, Santosh K. Shrivastava