Frank,

I know nothing about VSE, but anyway I would like to comment on DB2/LUW
authentication.

When you are connecting to DB2/LUW database you have to specify user
and password, eg. CONNECT TO dbonluw USER dbuser USING password.
Sometimes the user is different from the user that runs application, so
in your case the dbuser/password should be stored within a batch
script. On z/OS you can configure Communications Database to store
users and passwords when connecting z/OS client to DB2/LUW database (as
described in: "Understanding DB2(R): Learning Visually with
Examples", Appendix E),but I don't know how it differs from DB2 for
VSE.

How DB2/LUW authenticates depends on DB2 instance configuration. With
default configuration it is based on operating system users and
passwords on DB2 server. But also you can write your authentication
plugin (GSS-API), which for example positively authenticate only users
who are connecting from certain application. The same users might not
be authenticated, when connecting from CLP. There is set of articles on
ibm.com/developerworks describing DB2/LUW authentication.
Authentications plugins are used in special cases, so probably not in
your case.

-- Artur Wronski