SOA Based Design for Migrating Legacy Applications into Multi-Tenant Services

Multi-tenancy is the core concept of design for modern cloud computing services. Multi-tenant applications leverage the optimum usage of the underlying resources which in turn contributes to the high profit margin by decreasing the expenses on infrastructure. Legacy applications have their own blend of resources and infrastructure which are often not shared by other applications even though all applications are owned by a single organization. Therefore, it becomes an imperative to migrate such kind of legacy applications into multi-tenant services in order to seamlessly share the resources and decrease the cost on infrastructure, operations and maintenance. This paper mainly discusses how the legacy applications can be migrated into multi-tenant services by adopting an approach of Service Oriented Architecture (SOA). SOA based design modularizes an application into the loosely coupled services which can be exposed to any third party applications through an interface. Moreover, SOA based solutions foster high level of synergy into legacy applications in terms of shared resources, unified operations and maintenance, faster development and deployment of the new applications/services etc. This paper presents the empirical and practical notes on effective utilization of the SOA based design to migrate the legacy applications into multi-tenant services. The proposed solutions in this paper offer an alternative to outsource the development and operations tasks which in turn reduces the overall cost for long term sustainable businesses.