When you use an image catalog, you preload all your media so
that you do not need to handle the physical media when you perform the installation.
You do this by copying the images from the physical media
or
from files received through electronic software delivery to a file in
the integrated file system and then use these preloaded images to install.
The topic
Virtual
optical storage describes
further the concepts and uses of virtual optical media.
Image catalog for a virtual optical device describes
the requirements for using image catalogs.
Note: You cannot use
a virtual tape image catalog to install or upgrade an i5/OS™ release.