A Survey on Evolution of Cloud Technology and Virtualization

The term cloud is termed as a collection of resources both physical and virtual. The customers across the globe are accessing the services of the cloud. The key elements of the data center formed by the cloud are compute, network, storage, application and DBMS (Database Management System). The services provided by a real machine are imitated by the virtual machines. The services offered are for resources like CPU (Central Processing Unit), NIC (Network Interface Card), memory and hard disk. NIC is used to connect the system to the network. The virtual machines are created by software’s like hypervisor. The hypervisor serves as the Virtual Machine Monitor (VMM). It forms as an intermediate between the physical machine and virtual machine. VMware Workstation Pro, Oracle Virtual Box are the examples of hypervisor. The operating system (OS) of the real machine is called as “host OS”. “Guest OS” is the operating system of the virtual machine formed. The number of virtual machines created depends on the underlying hardware of the physical machine with sophisticated hard disks like SSD (Solid State Drive). A virtualized data center with resources is simulated using CloudSim and the results are interpreted.