OSI/TS SCF Reference Manual

Examples of Command Files
OSI/TS SCF Reference Manual—424832-001
C-15
One TSP Process Supporting Each X25AM Line
Because transport connect requests can arrive on any line at any time, there must be at
least one transport connect attach outstanding on one of the TSP subdevices for each
X25AM line.
The following subsections contain a discussion of the advantages and limitations of this
type of configuration, as well as an example command file.
Advantages
This type of configuration has the following advantages:
•
Fault tolerance. Problems with any one process cannot disrupt the whole
application. Any faulty process can be restarted and the full throughput restored in a
short time.
•
Load distribution. It is possible to balance the load between the TSP processes.
•
Resources. Additional resources can be made available at any time, even online, by
increasing the number of TSP processes.
•
Startup time. The startup time is usually shorter than in the previous configuration
because each process only works with its own portion of the total number of
subdevices.
Limitations
This kind of configuration is more complex to manage. For users of transport class 1 or
class 3, the Transport Layer recovery mechanism can possibly fail when the X.25
Figure C-4. Large Application Configuration: Single TSP for Each X25AM Line
Transport Layer
Network Layer
Data Link Layer
030
$X25A
(X25AM)
$X25B
(X25AM)
$X25C
(X25AM)
$X25D
(X25AM)
$TSP1 $TSP2 $TSP3 $TSP4