Modeling and Automating Analysis of Server Duty and Client Obligation for High Assurance

In today´s distributed service system which is often composed of heterogeneous servers and clients, the assurance of continuous operation of such system relies heavily on two things: the server continues to faithfully fulfill its duties, and the client continues to faithfully fulfill its obligations. However, as the complexity of distributed service system grows, it becomes much harder to correctly identify who is accountable for a service interruption or discontinuation when it occurs. In this paper, we propose an object-oriented approach to model and automate the analysis of server duty and client obligation for achieving high assurance of continuous service. With the formal model of server duty-client obligation interaction string and the use of an Accountability Analysis Engine, the proposed approach can effectively identify the party at fault in either online or offline mode when service interruption or discontinuation occurs.