OSI/FTAM Programming Guide

NonStop FTAM Programming
HP NonStop OSI/FTAM Programming Guide—528612-001
3-5
How an Association Is Established
Although your application might never use subdevice names, those names can be
useful in debugging. For example, you need to supply a subdevice name as input to
the SCF STATUS SU command, which provides you with useful information about the
association. (For an explanation of the information this command returns for initiator
subdevices, see Section 6, FTAM Application Management.) To obtain the subdevice
name programmatically, use the APS_STATUS_ procedure, which returns the
subdevice name in its device-name parameter.
How an Association Is Established
This subsection enumerates the tasks performed in establishing an FTAM association
through an initiator and the OSI layers providing the underlying services. Some of the
steps described below use information you provide in the FTM_INITIALIZE_REQ_
procedure call; most of the steps, however, represent tasks internal to the relevant
processes, which are performed without application intervention. This complete
description is provided as background information on the establishment of an
association.
Figure 3-2 on page 3-6 illustrates the actions taken after an application makes a call to
the FTM_INITIALIZE_REQ_ procedure. The numbers on the figure refer to the list of
steps below. These steps assume that the NonStop FTAM subsystem has been
started. For information on setting up and starting the NonStop FTAM subsystem, see
the OSI/FTAM Configuration and Management Manual.
These steps take place when an application makes a call to the
FTM_INITIALIZE_REQ_ procedure:
1. On behalf of the application, the FTAM API sends the APLMGR process specified
in the aplmgr-name parameter a register request to establish an FTAM
association using an available initiator.
2. The APLMGR process selects an initiator, chooses an initiator subdevice (SU)
name, and sends a request to the initiator to add a subdevice.
3. The initiator adds the subdevice and responds to the APLMGR process.
4. The APLMGR returns the subdevice name to the FTAM API.
5. On behalf of the application, the FTAM API opens the initiator’s subdevice and
sends a message to request an association through that subdevice. This message
includes the local common name, or OSI address if specified, and the remote
common name or OSI address of the responder with which the application wants
to establish communication. The local-appl and remote-appl parameters of
the FTM_INITIALIZE_REQ_ call provide this information.
6. If the FTM_INITIALIZE_REQ_ call was made in nowait mode, the FTAM API
returns to the application a connection endpoint identifier (CEPI) in the cepi
output parameter of the FTM_INITIALIZE_REQ_ procedure.
7. The initiator sends a register request to the configured OSI manager process to
establish an association with the TAPS process. The register request includes local