Caching is gaining popularity in cloud world. It is one of the key technologies which play a major role in bridging the performance gap between memory hierarchies through spatial or temporal localities. In cloud systems, heavy I/O activities are associated with different applications. Due to heavy I/O activities, performance is degrading. If caching is implemented, these applications would be benefited the most. The use of a Cache-as-a-Service (CaaS) model as a cost efficient cache solution to the disk I/O problem.