In the JES2 networking environment, each job entry subsystem must have a unique name by which it is defined to VTAM®. You use the APPLID parameter on the $T LOGON(n) command to identify JES2 as an application to VTAM. The $T LOGON(n) command also allows you to assign or delete a password for the JES2/VTAM interface and diagnose SNA problems by monitoring the interface and recording all SNA events on the console with master level authority. You use the $S, $P, and $E LOGON(n) commands respectively to start, stop, and restart the JES2/VTAM interface.