Service-Oriented Architectures (SOAs) have widely been accepted as the standard way of building large-scale, heterogeneous enterprise IT systems. In this paper, we explore the current limitations of testing contemporary SOAs, which are typically assemblies of various components, including services, message buses, business processes, and support components. We argue that, currently, SOA testing is too much concerned with testing single services or business processes, while there is little scientific literature on holistic testing of contemporary SOAs that includes all critical components and their mutual dependencies and interactions. In this paper, we detail the architecture of contemporary SOA, thoroughly assess the current state of research in respect of their testing, and introduce the notion of SOA criticality metrics as indicators for an individual component's criticality for the SOA as a whole. We enumerate an initial metric set for various component types and interactions, as well as discuss how these metrics can be used for testing contemporary SOA.
