SNAX/APC Management Programming Manual

Comparing DSM Applications and SCF
Introduction to SNAX/APC
111813 Tandem Computers Incorporated 1–3
Comparing DSM
Applications and SCF
SCF provides an interface to SNAX/APC that allows you to control SNAX/APC
interactively. The programmatic interface provided by DSM—including the
Subsystem Programmatic Interface (SPI) and EMS—offers the following advantages:
Programs can handle many routine SNAX/APC management tasks, which frees
operators and other network-management personnel to do work that requires
judgment and creativity.
Information acquired from interactive interfaces often requires modification or
interpretation before it can be used by a programmatic application; this increases
the potential for error. Information obtained through the DSM programmatic
interface, on the other hand, can be used directly by an application to control its
actions, produce reports, and so forth.
Applications that use the DSM programmatic interface can perform tasks that once
required the use of two or three interactive interfaces. Such an application can
communicate with multiple subsystems.
Applications can be tailored to the needs and configuration of your network.
You could write an application that uses the SPI interface to issue equivalent Change
Number of Sessions (CNOS) verbs. For example, your CNOS application could detect
the failure of a CNOS conversation, and generate the EMS event APC-EVT-CNOS-
CONV-FAIL. Your application could also monitor the events occurring in the
SNAX/APC subsystem and react appropriately.
Your applications also can communicate with subsystems other than SNAX/APC. For
example, you could write an application that configures and starts the SNAX/CDF
subsystem, and then configures and starts SNAX/APC.
As another example, you could write an application that monitors the events reported
by the Expand subsystem, as well as those reported by the SNAX/APC subsystem.
This application could also send requests to both the Expand subsystem and the
SNAX/APC subsystem to manage the network.
Note This manual includes information that is specific only to the SNAX/APC programmatic interface. If you are
writing a management application for SNAX/APC, you will also need to use the manuals listed in the
preface to this book.
Figure 1-2 illustrates how SNAX/APC fits into the DSM architecture. The following
subsection, “Management Programming for SNAX/APC,” discusses the
programmatic elements and considerations.