How does a facility get associated or assigned to a remote connection? Is the facility specified in the connection request? Or is a remote connection implicitly associated with the APPC facility?
The APPC facility is documented in the IBM z/OS MVS Planning: APPC/MVS Management manual.
Advanced Program-to-Program Communication (APPC) is an implementation
of the Systems Network Architecture (SNA) LU 6.2 protocol on a given system.
APPC allows interconnected systems to communicate and share the processing of programs.
So for example with DB2 DDF, needs APPC to come up so you can then use TCP/IP for clients to connect.
RACROUTE REQUEST=VERIFY,ENVIR=CREATE (signon) call from DDF.
Anytime there is a VERIFY=CREATE call Top Secret will check for access to the appropriate
FACILITY (Top Secret terminology). The signon is occurring under APPC and so
the APPC facility is being checked.
Even when the user is not using APPC to connect to DB2, we still check to see if they have access to APPC facility class.