The user key CSA was available for all up to z/OS 2.3 for ISVs. It has been used for data sharing between STC’s and programs, but with z/OS 2.5 it is not available anymore.
We are currently busy upgrading to z/OS 2.5 but need to fix this before we can go to z/OS 2.5.
CSA will be removed with z/OS 2.4 and onwards.
Release : 14.0
Component : Spool