A computing system includes a physical server having a single instance of
an operating system; and a plurality of virtual environments running on
the physical server and directly supported by the single instance of the
operating system. Each virtual environment responds to requests from
users and appears to the users as a stand-alone server having its own
instance of the operating system. Each virtual environment has a
plurality of objects associated with it and supported by the operating
system. Some of the objects are private and other objects are shared
between multiple virtual environments. One virtual environment cannot
access private objects of another virtual environment.