User's Manual Part 3

PERFORMING DOWNLOADS
Omni 3600 Download Differences
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MNI 3600 REFERENCE MANUAL 75
• Downloaded certificates (receiving terminal) must synchronize with the
certificate data present in the certificate tree. Synchronized means the
following:
• The certificate tree of the receiving terminal can be no more than one
revision out-of-sync with the certificate tree on the sending terminal or the
files on the receiving terminal do not successfully authenticate. In this
case, the term revision refers to any generic change to the current sponsor
and signer certificates stored in the certificate tree of a deployment
terminal.
• When the back-to-back download completes and all certificates and signature
files authenticate, the receiving terminal restarts. If the name of the *GO
application is specified in the Group 1 CONFIG.SYS file of the receiving
terminal, the application executes and the application prompt or logo displays
on the terminal.
Timing Considerations Due to the Authentication Process
The file authentication process takes some time. The total amount of time
required depends on a number of factors, including:
• the number and size of application files,
• the number of certificates and signature files, and
• if you are using the file compression feature of Download Manager to perform
the download.
Here are a few additional considerations that may affect the total elapsed time
required to complete the download operation:
• Because additional processing steps are required, an operating system
download takes longer to complete than an application download (several
minutes as opposed to a few seconds).
• The download order of a batch of certificate files may affect total processing
time. Digital certificates are validated in a looping process where the validation
process cycles as many times as necessary to establish the proper
relationship and position of a given certificate in the certificate tree that exists
in the terminal.
To optimize the authentication process, you can download certificates in a
higher-level-certificates-first order. This way, they process faster than a
random order download.
Optimize Available Memory Space for Successful Downloads
One certificate file or signature file requires approximately 400 bytes of memory
space. The application designer must account for the extra memory required to
download and store these special files.