Hiya,
I am using 'neon shadow client' to establish the connection with DB2 (located in mainframe env).
Qs:
1) Is it mandatory to stick with Neon (appln connect to db2 mainframe)?
2) If there are alternate way for Neon (DB2 client), which type of DB2 driver is advisable?
3) Any other dependencies or issues do I need to take care whilst neon to DB2 Client JDBC connection?

Pls suggest.
Cheers.

Neon is a third party client performing the same function as IBM's DB2 Connect. There are others, but Neon is one of the better known. All (including DB2 Connect) are extra cost items.

You have to have some version of mainframe client, except for the case of Type 4 drivers, which can access the mainframe without any extra software.
However, Type 4 drivers are only available with the newer versions. You did not state your version, so we cannot give a complete answer.