1. A method implemented in a computer infrastructure having computer executable code tangibly embodied on a computer readable storage medium having programming instructions operable to: receive a system architecture model of a system using a processor, wherein the receiving the system architecture model comprises: determining whether the system architecture model exists; importing the system architecture model when determined to exist; when the system architecture model is determined to not exist: identifying and capturing a components model of the system architecture model; identifying and capturing a connections model of the system architecture model; and refining the connections model into interface models; annotating the system architecture model; and mapping from the system architecture model to one or more use case models; receive trigger coverage rules; determine system integration test (SIT) coverage for each connection and interface of the system architecture model; and select a set of use cases execution scenarios to satisfy the SIT coverage.