OSI/FTAM Programming Guide

NonStop FTAM Programming
HP NonStop OSI/FTAM Programming Guide—528612-001
3-3
Subdevices
Control Facility (SCF) allows you to configure or modify a default common name for an
initiator process; this common name must correspond to a specific OSI address
registered in the management information base controlled by the OSI manager
process. For information about the management information base controlled by the
OSI manager, see the OSI/AS Configuration and Management Manual.
The common name does not necessarily refer to a particular initiator. If your FTAM
configuration includes several initiator processes, the APLMGR process assigns
initiators to applications in a round-robin fashion. What the common name does
determine is the application’s outgoing path to the network connection point of your
system; it identifies which of the OSI processes underlying the FTAM application will be
used in the association. As Figure 3-1 on page 3-4 shows, a NonStop FTAM
application can connect with the OSI network through either an X25AM or a TLAM
subnetwork. The NSAP address specified in the common name and the corresponding
network service provider (NSP) process determine the route data communications take
to the OSI network. The NSP process is associated with a particular hardware
controller board and controls a particular physical line into the communications
subnetwork.
Therefore, if your particular system configuration provides for several NSP processes
dedicated to different X25AM or TLAM subnetworks or to both types of subnetworks, it
is essential that you specify the appropriate common name in the local-appl
parameter of the FTM_INITIALIZE_REQ_ procedure call.
Figure 3-1 on page 3-4 provides an example of a configuration with one service
provider for application, presentation, and session services (the TAPS process of
OSI/AS), one transport service provider (the TSP process of OSI/TS), and two NSP
processes (X25AM and TLAM). In this configuration, the common name specified by
the application determines which NSP process will be used in the connection.
For more details on configuring addresses for NonStop FTAM, see the person who
manages your network or refer to the OSI/FTAM Configuration and Management
Manual.
Subdevices
A subdevice (SU) is a logical connection between a process at one OSI layer, such as
the initiator or responder, and the local OSI process, such as TAPS, that provides
services at the next lower layer. One subdevice is created for each association or
(below the Application Layer) each connection.
FTAM subdevices are created as a result of a call to the FTM_INITIALIZE_REQ_
procedure. When the application makes such a call, the FTAM API sends the specified
APLMGR process a register request to establish an FTAM association using an
available initiator. The APLMGR process then dynamically configures a subdevice for
the initiator process it selects. After APLMGR selects the initiator and configures the
subdevice for it, the FTAM API, on behalf of the application, opens the initiator’s
subdevice and sends a message requesting an association through that subdevice.
The common name or OSI address specified in the local-appl parameter then