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; and 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, and wherein the components model comprises at least one of a system, a sub system and a module of the system architecture model; receive trigger coverage rules; determine system integration test (SIT) coverage requirements for each connection and interface of the system architecture model using the received trigger coverage rules; and select a minimum set of use cases execution scenarios needed to cover and satisfy the SIT coverage requirements.