OSI/AS Management Programming Manual

C-Series and D-Series Compatibility
Introduction
056785 Tandem Computers Incorporated 1–21
OSI/AS Running in Mixed
C-Series and D-Series
Expand Networks
The following subsections contain OSI/AS-specific information for communicating
with processes having various combinations of version levels. In all cases, the version
compatibility rules described earlier apply between any two processes, regardless of
whether the processes are running in the same system or on different systems in an
Expand network.
For example, an application and a OSI/AS process can both be running in D-series
systems. When a connection is established, the application and the OSI/AS process
can run at either a high or a low PIN. The OSI/TS process for that same connection
may also be running in a D-series system, and can, therefore, run at either a high or
low PIN. However, that same connection may also use an X25AM process that is
running in a C-series system. Because the X25AM process requires a low PIN, the
OSI/TS process for that connection (which directly interfaces with the X25AM process)
must also run at a low PIN. The OSI/AS process is able to run at at high PIN because
it interfaces with an OSI/TS process running in a D-series system (even though it is
running a low PIN). Therefore, the connection might look like the following;
Application Process OSI/AS Process OSI/TS Process X25AM Process
D-series system:
HIGH PIN
D-series system:
HIGH PIN
D-series system:
LOW PIN
C-series system:
LOW PIN
In a different example, an application in a C-series system might establish a connection
with an OSI/AS process also running in a C-series system (either C21, or C30 or
higher), but the OSI/TS process and the TLAM process might be both running in
D-series systems. In this case, the TLAM process can run at a high PIN because it is
running in a D-series system and is interfacing to another D-series process. The
OSI/TS process must run at a low PIN (even though it is running in a D-series system)
because it directly communicates with a C-series process. The connection might look
like the following:
Application Process OSI/AS Process OSI/TS Process TLAM Process
C-series system:
LOW PIN
C-series system:
LOW PIN
D-series system:
LOW PIN
D-series system:
HIGH PIN
Note In Expand networks with mixed C-series and D-series systems, TAPS and TSP processes must adhere to
the C-series system file naming rules.
Managing C30 OSI/AS (in a D-Series System) Using C21 SCF or SCP (in a C-Series System)
New DSM functionality provided by the C30 version of OSI/AS is available only with
C30 or later versions of SCF and SCP. This means that new information fields
provided by OSI/AS are not accessible to nor displayed by C21 SCF.