Expand Management Programming Manual

MANAGEMENT PROGRAMMING FOR THE EXPAND SUBSYSTEM
restart terminals on that remote system. As another example,
if your EXPAND network contains an X.25 virtual circuit, you
could write an application that monitors the events reported by
the X25AM subsystem as well as those reported by the EXPAND
subsystem. This application could also send requests to both the
X25AM subsystem and the EXPAND subsystem to manage the network.
HOW APPLICATIONS FIT INTO THE ARCHITECTURE
An application uses the control-and-inquiry interface to the
EXPAND subsystem by sending requests (commands) to and receiving
responses from SCP. SCP passes some commands to the Network
Control Process (NCP), some to the Network Utility Process
($ZNUP), and some to the line handlers; these processes, in turn,
perform the specified actions. An application uses the Event
Management Service (EMS) to retrieve event messages generated
by the EXPAND subsystem by sending commands to and receiving
responses from an EMS distributor process.
Figure 2-1 illustrates how an application fits into the architec-
ture of the EXPAND subsystem.
2-2