1. A computer-readable storage medium containing instructions for controlling a computing device to implement an application topology, by a method comprising: discovering the application topology of a network; displaying graphical representations of computers and applications of the network represented by the discovered application topology; receiving from a user selection of graphical representations of computers and applications to be associated with selected computers to define a desired application topology of the network; creating installation packages for the computers specifying the applications to be associated with the computers, the installation packages indicating that different applications are to be installed on different computers; distributing the installation packages to virtual machines that represent the computers wherein the virtual machines are configured in accordance with the installation packages; and after configuration of the virtual machines based on the distributed installation packages, determining whether the desired application topology was implemented correctly by the virtual machines to which the installation packages were distributed by: discovering an application topology as represented by the configuration of the virtual machines; and comparing the discovered application topology as represented by the configuration of the virtual machines to the desired application topology to determine whether the desired application topology was implemented correctly by the virtual machines.