User's Manual Part 3

PERFORMING DOWNLOADS
Omni 3600 Download Differences
72 OMNI 3600 REFERENCE MANUAL
For data files, font files, and any other files that require authentication to meet
the application’s design specification, the application must ensure that these
files successfully authenticate.
While a signature file is being processed, it remains stored in the RAM file
system of the target file group. The target application file may be redirected
immediately on download to RAM or flash.
When the signature file successfully authenticates its target file, it is
automatically moved to same the file system and file group as the target file it
authenticates (that is, if *FA = 1).
The processing routine gives you visible and audible indications of if a specific
signature file successfully authenticates. The file authentication module does
not halt the process if a signature file fails to authenticate, but continues to the
next step: storing the downloaded files in their final locations in the terminal file
system.
6 Certificate files and signature files are retained in the RAM file system until the
file authentication process is complete. These special files are then either
deleted or automatically redirected to another file system or file group, as
previously described.
When an application file is authenticated, the operating system sets the file’s
read-only attribute to protect it from being modified while stored in terminal
memory. This is also true for a signature file retained in terminal memory.
When a signature file is assigned the read-only attribute, it is no longer
detected as a new signature file by the file authentication module on terminal
restart.
7 When all certificates and signature files are processed and special files
deleted or redirected as required, the terminal restarts and the *GO
application executes.
File Group Permissions
Now, consider how file authentication controls who (which business entity) can
store application files in which file groups in the Omni 3600 file system.
By inserting zero-length SETDRIVE.x and SETGROUP.n files into a download
list, you can specify which drive (x = I: RAM or F: flash) and which group (n = 1–
15) to store an application file. In addition to this file redirection protocol, the file
authentication module controls which files are allowed, under the authority of the
signer certificate used to sign them, to be stored in which file groups in the
Omni 3600 file system.
For example, if the terminal owner specifies that a loyalty application in be stored
GID2, the information is encoded in the sponsor and signer certificates issued by
the VeriFone CA for that terminal.