For ultimate security you can just turn off the NION's web interface. This will cause the NION to cease to respond to requests on port 80. It will still work fine for Kiosk2Go purposes.
The only issue with doing this is that to turn the NION's web interface back on, you will need to use the front panel of the NION on the n6, n3, and nX models. You will need to open the unit and connect a front panel board on the nE models.
Otherwise, you can use the web interface's User Accounts page to neuter the superuser account and instantiate your own user accounts with access. However, one shortcoming of this is that it does not stop someone from halting or erasing the role in the NION.
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