SQL Encryption with Instead of Triggers

To Whom it may concern;
We have been tasked to encrypt several fields in a data file the AS400.
I have been researching on the best approach with the least impact, which has brought my attention to SQL encryption using Instead of Triggers.
Does anyone have any insight with this method? It seems somewhat straight forward using insert, delete and update. Do I need to use API's in order to read this data? Is there a "Read' trigger? What type of Master key. The data file remains static once we have it on our disk, just need to retrieve it upon request.
Any insight on encrypting data fields in a file on the IBM AS400 would be much appreciated. We are currently at 6.1.
Thank You
Darlene
Darlene Wright
Programmer/Supervisor
CrossCheck, Inc.
707.665.2100
707.793.5799 Fax
darlenew@xxxxxxxxxxxxxxx<mailto:darlenew@xxxxxxxxxxxxxxx>
www.cross-check.com<http://www.cross-check.com>

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