The architecture of Star Student Project system encapsulates each application instance inside a virtual machine (VM). The use of VMs is necessary to provide isolation among entrusted users. Both Amazon EC2 and Microsoft Azure use VMs in their cloud computing offering. Each server in Star Student Project system runs the Xen hypervisor which supports a privileged domain 0 and one or more domain. Each domain encapsulates an application instance, which is connected to share network storage.