An application definition is described using one application descriptor with a number of nested sub-descriptors (and sub-sub descriptors). The descriptors correspond to Slice types in the IceGrid registry interfaces, and to XML element in an IceGrid XML representation.
IceGrid Admin maps these descriptors to nodes on a tree representation:
Page url: http://www.zeroc.com/doc/Ice-3.4.2/IceGridAdmin/index.html?app_descriptors.htm