JCloudScale: Closing the Gap Between IaaS and PaaS.

Building Infrastructure-as-a-Service (IaaS) applications today is a complex, repetitive, and error-prone endeavor, as IaaS does not provide abstractions on top of virtual machines. This article presents JCloudScale, a Java-based middleware for moving elastic applications to IaaS clouds, with minimal adjustments to the application code. We discuss the architecture and technical features, as well as evaluate our system with regard to user acceptance and performance overhead. Our user study reveals that JCloudScale allows many participants to build IaaS applications more efficiently, compared to industrial Platform-as-a-Service (PaaS) solutions. Additionally, unlike PaaS, JCloudScale does not lead to a control loss and vendor lock-in.