OSI/TS Configuration and Management Manual

Configuring the OSI/TS Subsystem
OSI/TS Configuration and Management Manual—424831-001
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One TSP Process Supporting Each X25AM Line
Advantages
This type of configuration has the following advantages:
Limitations
Due to the greater number of processes, this kind of configuration is more complex to
manage.
In addition, for users of transport class 1 or class 3, the Transport Layer recovery
mechanism can possibly fail when the X.25 network is not very reliable and generates
many network disconnections. This can occur when a remote Transport Layer entity
resynchronizes a transport connection, which causes a new network connection to be
established. This new network connection does not necessarily arrive at the same TSP
process that is participating in the resynchronizing process. However, this situation does
not usually develop because network resets are more likely to occur than disconnections
and are handled by the TSP process without difficulty.
This anomaly in this type of configuration does not occur with class 2.
Command File for a Single TSP Process Supporting Each X25AM
Line
In this example command file, four TSP processes support four X25AM lines. Each line
is configured for three subdevices. (In reality, the number of TSP subdevices for each
line would be much larger.)
The source code file for this example is provided as part of the OSI/TS software. It
resides (by default) in the volume and subvolume $SYSTEM.ZOSITS. The source code
for this example is provided in the file EXCFG7, as follows:
=============================================================
== File: EXCFG7
==
== Example command file for configuring and starting
== processes and subdevices for large applications in which
== a separate TSP process supports each X.25 line
== (X25AM). Each line is configured for three
== subdevices. SCF must be running before you use the
== OBEY command to invoke this file.
==
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.