OSI/AS SCF Reference Manual

OSI/AS Trace Facility
OSI/AS SCF Reference Manual—424121-001
3-5
How Trace Records Cross the OSI Layers
Figure 3-3 shows how output from one service layer becomes the input to the service
layer below.
General Considerations for the Trace Facility
•
An APS user can make a connection to any of the three service layer modules. If the
connection is made to ACSE, the trace file will contain ACSE, presentation, and
session records. If the connection is made to presentation, the trace file will contain
only presentation and session records.
•
A trace file will typically contain records of several concurrent connections. Each
connection is identified by a unique subdevice name in the trace record.
•
You can limit the number of trace records that you collect by the options provided in
the OSI/AS SCF TRACE command. After collecting trace information with the
TRACE command, you can limit the information you format by the options
provided in the PTrace SELECT and FILTER commands.
Figure 3-3. How Trace Records Cross the OSI Layers
025CDT .CDD
ACSE
ACSE User
ACSE Provider
State Machine
and Error
Presentation
Presentation User
Presentation Provider
State Machine
and Error
Session
Session User
Session Provider
State Machine
and Error