A queue theory-based approach to staff software maintenance centers

The Internet and WEB pervasivenesses are changing the landscape of several different areas, ranging from information gathering/managing and commerce to software development, maintenance and evolution. Software companies having a geographically distributed structure, or geographically distributed customers, are adopting information communication technologies to cooperate. Communication technologies and infrastructures allow the companies to create a virtual software factory. This paper proposes to adopt queue theory to deal with an economically relevant category of problems: the staffing, the process management and the service level evaluation of massive maintenance projects in a virtual software factory. Data from a massive corrective maintenance intervention were used to simulate and study different service center configurations, in particular, a monolithic configuration and a configuration corresponding to a multi-phase maintenance process where several maintenance centers cooperated. Queue theory allowed effective control of the process supporting project management decisions. The mathematical tool provided a means to assess staffing, evaluate service level and balance the workload between maintenance centers while executing the project.