Software maintenance and operations hybrid model: An IT services industry architecture simulation model approach

Since its beginnings in the late 1960s, the IT services industry has signed long-term (10 to 20 year) contracts to maintain software and operate a system for a fixed decreasing price. The motivation for this paper stems from forty years of watching software maintenance artifacts and operations artifacts continue to diverge down two separate paths filled with duplication and unused information. Occasionally, a well-annotated simulation model has been used effectively to bring these two artifact-paths together and efficiently maintain the software and operate the system within contracted performance goals, called service level agreements. This paper proposes an architecture simulation model hybrid, built from existing software development artifacts and operations artifacts, which can endure for the operational life of a system (an average of eighteen years). In order to show the relevance of the hybrid approach, the complete development and maintenance lifecycle of a large-scale customer order system case is studied. The services industry case high-lights the gaps contained in current simulation models and presents modeling extensions to fill the breaches.