Do not have consistent masking using FDM with Oracle vs Mainframe masking DB2

Document ID : KB000007867
Last Modified Date : 14/02/2018
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Issue:

My masking is resulting in issues with inconsistent results between FDM Oracle and Mainframe DB2.  The resulting mask from FDM does not match the same input data's masking from a DB2 Mainframe masking.  The RL_RN code is rendered as two different values, thus producing two different masking results from the same input and same seedlist.

Environment:
TDM 4.1 GA with ORACLE DatabaseMainframe with DB2 and 5.4 TDM Mainframe release.
Cause:

Masking Names/Addresses in Oracle and DB2 results in different values.  The RL_RN hashcode is different.   How does the TDM MF masking program mask the DB2 names RL_RN = 2027 as oppose to 2765? Why not use the same FDM RL_RN value? 

TDM FDM masking function HASHLOV hashes on column RL_RN = 2765 (mask to NAME = BRIAN FRIEND) 
TDM MF masking function HASHLOV hashes on column RL_RN = 2027 (mask to NAME = KAREN COVINO) 

Note: We are using DB2 Seedlists to mask consistently for both Oracle and DB2

Resolution:

The issue is in the setup.  

First, in the PARMCD input to the mainframe masking program, set - 

HASHTYPE=JAVA 

In addition, if the column containing the ssn is a string type which may have leading/trailing blanks set - 
TRIMMEDHASHLOV=Y 

It is important to note that the HASHTYPE=JAVA on the Mainframe parameter side is what ultimately resolved this issue.