The principles of information system interoperability extend beyond just architecture planning to include activities such as system acquisition, technical design, implementation, and certification. LISI extends to all of these by considering the increasing levels of sophistication for system-to-system interaction; i.e., the thresholds of capabilities that systems exhibit as they improve their ability to interact with each other. The LISI Reference Model provides an accepted representation of system interoperability, including a common vocabulary that allows agreement on standards for facilitating interoperability in terms of the PAID paradigm. The LISI Reference Model also provides automated methods for conducting interoperability assessments and for deriving performance metrics based on operational testing and evaluation. Finally, the reference model serves as a process that can be used for analyzing and establishing cooperative interoperability agreements within and among communities of interest.
For more information concerning the LISI Reference Model, its use for evaluating architectures,applicability to the acquisition process, and its relationship to the test and evaluation community refer to the Architecture Working Group Final Report