Moving to SaaS: Building a Migration Strategy from Concept to Deployment

Synopsis

The chapter presented here starts with an introduction of the topic and a presentation of the current approaches to migrate legacy applications to SaaS, including the distinction of SOA and SaaS concepts. The authors present which challenges that are facing the companies that wish to migrate to the cloud delivery model. The main body of the chapter is devoted to the technical outline of the proposed solution starting with the establishment of the basis for the migration strategy (analysis of the initial and the target situation and a technical and business feasibility analysis) and proposing a set of methods and technologies for the performance of the migration as well as the provision of the final service.

The chapter rounds off with the presentation of the stated approach validation in eight companies in Spain and a detailed explanation of a real use case extracted from one of those companies. The chapter concludes with the considerations arisen from these first implementations of the solution.

General Objectives and Perspective of the Chapter

The transition from a traditional software development and delivery model to the SaaS world is proving to be not trivial and therefore many changes are needed to be performed in order to accomplish the technical, application and business requirements of SaaS. This triple migration is complicated and an overall systematic and standardized approach is, for the time being, not publicly available. Thus, companies humbly face the decision of which existing technology to migrate to and via which distribution channels to make it available but in any case, without risking the sustainability of their business. This decision requires not only from a method but also from tools that provide meaningful figures that can be used in this decision making process. These tools shall at least cover the calculation of the running costs for SaaS solutions as well as the calculation of the income expected from such offers, while considering also additional and numerous factors, which can be levied only based on the choice of a specific platform.

The innovative aspect of the approach presented in this chapter is that it will lead companies in this re-engineering and architecture modernization effort, by analyzing the source code (i.e. searching for clones, degree of coupling, etc.) as well as the architectural patterns in the application-to-be-migrated. This approach will also provide an analysis on

• 1.

  Where the current architecture does not address SaaS architectural requirements,

• 2.

  Specific changes needed, as well as

• 3.

  Suggestions of existing software components and services.

Interplaying with that, other factors will be taking into account such as business goals and models, costs, effort, impact, ROI, and payback.