In spite of its name, the Image Cache is not a storage facility for image files. Rather, it is a system for loading image and template files into interviews directly from a computer in the Interview Tier so that the files do not have to be copied onto the Web Tier. This helps simplify activation because image and template files need only be copied onto the Interviewing servers. This is particularly important in a demilitarized zone (DMZ) where Interview and Web servers may not have network access to each other's file systems. The following diagram shows how the Image Cache is used in a DMZ configuration:

The name of the Image Cache program is ImageCache.aspx and it is normally installed in c:\InetPub\wwwroot\SPSSMR\ImageCache on all computers running the Web, Interview, and Accessories services.