Summary of ETO implementation

The following figure illustrates the ETO concepts and shows an overall view of an ETO implementation.

Figure 1. Summary of ETO implementation

•  1  The system-defined descriptors that are built during system definition are stored in IMS.PROCLIB as member DFSDSCMx.
•  2  Your user-defined descriptors that are written to override the system definition defaults are stored in IMS.PROCLIB as member DFSDSCTy. MFS descriptors that are processed by the MFS Device Characteristics Table utility (DFSUTB00) are stored in the device characteristics table.
•  3  Logon, user, and MSC descriptors are loaded at IMS initialization using the input from IMS.PROCLIB.
•  4  The Logon and Logoff exit routines are called during logon and logoff.
•  5  The Signon and Signoff exit routines are called during signon and signoff.
•  6  Output is delivered to the destination specified in the Destination Creation exit routine, unless the user is created during signon.
•  7  If IMS is unable to determine where output should be delivered, the messages are added to the dead-letter queue. Messages might not be delivered because:
  • The user name is not a valid user ID.
  • The user signon is rejected.
  • A physical-to-logical relationship does not exist between the device and the LTERM.
•  8  RACF® (or an equivalent product) manages security in the ETO environment.