1. A system, comprising: a host server with one or more memory locations configured to store one or more isolated environments and one or more host server update-caches, wherein the isolated environments comprise at least one or more applications, and files and executables for said one or more applications; one or more clients comprising one or more memory locations configured to store one or more isolated environments, an update-cache for each isolated environment, and a client operating system, wherein said one or more isolated environments comprise at least one or more applications, and files and executables for said one or more applications; and a client policy manager configured to perform one or more of store client credentials for the one or more clients, authenticate the one or more clients, and enumerate available isolated environments for the one or more clients; one or more data communication links between the one or more clients and the host server; wherein one or more of said isolated environments on the host server are streamed to the one or more clients over the one or more data communication links, and said one or more host server update-caches are configured to identify which files in said streamed isolated environments have changed since last being streamed to said one or more clients.