OSI/AS Configuration and Management Manual

Installing and Configuring the Subsystem
OSI/AS Configuration and Management Manual—424119-001
4-7
TLAM Considerations
Deleting X25AM Subdevices
During the connection-release phase, the TSP process determines whether to retain the
network connection used by the transport connection or to discard it, based on the
following criteria:
•
Value of the MULTIPLEX attribute
•
Network connection ownership
If an X25AM subdevice is not reused by either local or remote transport entities, actual
deletion of an X25AM subdevice occurs after the timeout of the
X25DISCONNECTDELAY timer.
Addressing Standards
Network Layer addressing in the 1980 X.25 standard is different from that in the 1984
X.25 standard. You must, therefore, specify to OSI/AS which standard your network
implements. If you are using a network that implements the 1980 X.25 standard, you
must configure your NSAP ENTRY objects using ADD or ALTER commands that
include the clause NETADDR-MODE X25-1980. If your network implements the 1984
standard, you can optionally specify NETADDR-MODE NORMAL (the default).
X25AM PTP Protocol
The OSI/AS subsystem uses the PTP (process to process) interface of X25AM.
Therefore, when using SYSGEN to install each X25AM line to be used by OSI/AS, you
must do either one of the following:
•
Leave the L4PROTOCOL modifiers unspecified.
•
Specify the appropriate value for the L4^PTP^PROTOCOL attribute.
Maximum TPDU Size
The maximum TPDU size to be used for Transport Layer connections over X25AM is
limited to the maximum I/O size supported by X25AM, as specified by the
MAXIOSIZE SYSGEN modifier; the MAXIOSIZE default is 4096. Ordinarily, the
OSI/TS subsystem automatically determines each X25AM line’s maximum I/O size.
However, if your configuration requires a TPDU size of 8192, you must set the X25AM
MAXIOSIZE attribute to 8192—otherwise, the 8192 TPDU size does not take effect.
TLAM Considerations
TLAM is a system I/O process that provides local-area, connectionless-mode
subnetwork service over standard 802.3 and 802.4 networks. It has an application
interface and an interface to an intelligent controller that runs the data-link protocols
(logical link control and CSMA/CD).