Variability as a Service: Outsourcing Variability Management in Multi-tenant SaaS Applications

  • Ali Ghaddar
  • Dalila Tamzalit
  • Ali Assaf
  • Abdalla Bitar
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7328)


In order to reduce the overall application expenses and time to market, SaaS (Software as a Service) providers tend to outsource several parts of their IT resources to other services providers. Such outsourcing helps SaaS providers in reducing costs and concentrating on their core competences: software domain expertises, business-processes modeling, implementation technologies and frameworks etc. However, when a SaaS provider offers a single application instance for multiple customers following the multi-tenant model, these customers (or tenants) requirements may differ, generating an important variability management concern. We believe that variability management should also be outsourced and considered as a service. The novelty of our work is to introduce the new concept of Variability as a Service (VaaS) model. It induces the appearance of VaaS providers. The objective is to relieve the SaaS providers looking forward to adopt such attractive multi-tenant solution, from developing a completely new and expensive variability solution beforehand. We present in this paper the first stage of our work: the VaaS meta-model and the VariaS component.


SaaS multi-tenant variability 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Ali Ghaddar
    • 1
    • 2
  • Dalila Tamzalit
    • 2
  • Ali Assaf
    • 1
  • Abdalla Bitar
    • 1
  1. 1.BITASOFTNantesFrance
  2. 2.LINAUniversité de NantesFrance

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