This task is usually performed by a z/OS system programmer or DB2 DBA.
The Mainframe HOST DB2 ODBC interface uses a plan named DSNACLI. Part of the DB2 installation process involves binding this plan and its associated packages (see member DSNTIJCL in SDSNSAMP).
For more information, see the DB2 z/OS ODBC Guide and Reference.
The mentioned interface is not the JDBC interface. Some windows DESKTOP software, including many IBM applications use JDBC. Just because your windows software is functional does not mean the mentioned task has been performed correctly.