Towards Flexible and Reusable SaaS for Multi-tenancy To design, implement and bind multi-functional variability for Rich-Variant services

Software-as-a-Service (SaaS) is a new delivery model, that involves providing applications to the customer on demand over the Internet. SaaS promotes multi-tenancy as a tool to exploit economies of scale. However, the flexibility of an application to be adapted to individual tenant's needs is a major requirement. Thus, we initiate in this paper to an approach proposing a more flexible and reusable SaaS system for multitenancy. This approach consist on integrating a functional variability using Rich-Variant Components with a deployment variability enabling the customers to choose with which others tenants they want or don't want to share instances. The approach presented enables exploiting the economies of scale while avoiding the problem of customers' hesitation about sharing with other tenants.