Legacy to Cloud Migration: Assessing the Cloud Readiness of Legacy Software Systems

The demand for cloud computing services is increasing steadily as more companies realize the benefits that are achievable through this new delivery model for IT services. These benefits come in the form of reduced costs, increased business agility and scalability – which gives companies increased responsiveness to customer needs. Companies consuming cloud services have the unique ability to provision IT resources precisely as they are needed; only paying for what is consumed. Shifting to this utility model for IT services is seen as a solution for the tight budgets that constrain many of today’s IT departments. A major obstacle to reaching the full potential of cloud computing is the myriad of legacy systems still in widespread service today. Legacy systems typically run on unsupported platforms and are written in older programming languages and architectures that cannot take advantage of the full potential of what cloud computing has to offer. These legacy systems often perform mission critical functions and contain within them years of valuable business logic and data that cannot be simply discarded. This master thesis investigates the various approaches available to businesses for handling this legacy problem. It begins by presenting and evaluating the state of the art software modernization options, which are a prerequisite for many legacy systems that need to be moved to a cloud environment, and identifying the most relevant issues that need to be considered for cloud migration projects. The characteristics of the legacy systems, specifically those relevant for cloud adoption, are then identified and organized to determine the ideal migration solution, including both the modernization approach and the resulting cloud service delivery model, for a particular legacy system. The resulting Assessment is designed to facilitate smart decision making among CIO’s and other decision makers in migration projects involving legacy systems that need to be moved to a cloud environment.