Application virtualization reduces system integration and administration costs by maintaining a common software baseline across multiple diverse computers in an organization. Remote applications run on a server. End users view and interact with their applications over a network via a remote display protocol. The remote applications can be completely integrated with the user's desktop so that they appear and behave the same as local applications, through technology known as seamless windows. The server-based operating system instances that run remote applications can be shared with other users through a terminal services desktop, or the application can be running on its own OS instance on the server a VDI desktop. A constant network connection must be maintained in order for a remote application to function. With streaming applications, the virtualized application is executed on the end user's local computer. When an application is requested, components are downloaded to the local computer on demand. Only certain parts of an application are required in order to launch; the remainder can be downloaded in the background as needed. Once completely downloaded, a streamed application can function without a network connection. Various models and degrees of isolation ensure that streaming applications will not interfere with other applications, and that they can be cleanly removed when closed. Application virtualization is layered on top of other virtualization technologies, such as storage virtualization or machine virtualization to allow computing resources to be distributed dynamically in real time. In standard computing, applications install their settings onto the host operating system, hard-coding the entire system to fit that application's needs. With application virtualization, each application brings down its own set of configurations on-demand, and executes in a way so that it sees only its own settings. This leaves the host operating system and existing settings unaltered. Markoni Computing provides services of Application virtualization through the use Microsoft App-v, Vmware Horizon and Citrix Xenapp.