ANALYSIS OF SaaS MULTI-TENANT DATABASE IN A CLOUD ENVIRONMENT

Recently, cloud computing became a dominant field in the information technology world. It prevails over both academia and industry. Cloud Service Providers (CSP) provide many services such as storage, platform and applications. However, security is the most critical concern that impedes the dominance of cloud usage. Since Software as a Service (SaaS) security issues are under the end-user’s control, it became more common than other cloud service models. In addition, its popularity comes from its remote delivery for the application functions over the Internet to subscribed users. Multi-tenancy is the main property of SaaS, it allows vendors to provide multiple requests and configurations through a single instance of the application. In this context, a customer is known as a "tenant". In the same way, a single database is shared amongst customers to store all tenants ’ data: this is known as "multi-tenant database". This reduces operational and maintenance costs; offers more reliability. On the other hand, the occurrence of a problem affects all customers. The risk of leaking information is the most undesirable situation in this architecture. In addition, multi-tenant databases are the most suitable architecture for data mining: this may increase the income of CSPs. From tenants’ perspective, this approach lacks flexibility. This paper explores the different implementation approaches used in multi-tenant databases. It also provides an analytical study on each of the presented approaches