In software engineering, service virtualization or service virtualisation is a method to emulate the behavior of specific components in heterogeneous component-based applications such as API-driven applications, cloud-based applications and service-oriented architectures.It is used to provide software development and QA/testing teams access to dependent system components that are needed to exercise an application under test (AUT), but are unavailable or difficult-to-access for development and testing purposes. With the behavior of the dependent components "virtualized", testing and development can proceed without accessing the actual live components.Service virtualization is recognized by vendors, industry analysts, and industry publications as being different than mocking. See here for a