Field Level security functionality NEW in A9.3!
Field Level Security is an enhancement for A9.3.1 that utilizes DB2 column level encryption first delivered in i7.1. This feature uses a database level IBM i7.1 operating system database-level convention called Field Procedure (Fieldproc). Implementation of this feature allows masking of values contained in the display file. Whether or not a particular field is "masked" is determined by security authorization for the user. This feature also determines if a user is authorized to modify the field.
For more information, please refer to Doc ID 1460223.1 "A9.3 Security Setup".
Working with Field Level Masking
http://docs.oracle.com/cd/E26228_01/doc.93/e21958/ch_ww_security_field.htm