SNAX/HLS Diagnosis and Support Manual

Glossary
Glossary–2 104706 Tandem Computers Incorporated
communication interface unit (CIU ). A hardware unit that, together with the SNAXLink
software and the CAU, provides a direct channel link between a Tandem system and
an IBM system. The CIU controller attaches directly to the Tandem processor through
a standard I/O card slot.
Communications Management Interface (CMI). A Tandem subsystem that is used for
configuring and controlling communications subsystems such as SNAX/XF. See also
Subsystem Control Facility.
configuration. The definition or alteration of characteristics of an object.
CONTROLLERS paragraph. A paragraph within the SYSGEN configuration file that is
used to describe the I/O controllers required to support SNAX/XF lines and to define
the pseudocontrollers required by the SNAX/XF Service Manager.
CRT. Cathode ray tube.
CRT protocol. One of the SNAX/XF and SNAX/CDF high-level 3270 protocols. The
CRT protocol supports block-mode communications with display terminals and
printers. The CRT protocol allows the calling process to communicate with a device as
if it were an ordinary file. See also PRT protocol and interactive terminal interface
(ITI) protocol.
CSW. See channel status word.
data definition language (DDL). A Tandem product for defining data objects in Enscribe
files and translating object definitions into source code for languages and other
products in NonStop systems.
data–terminal equipment (DTE). That part of a data station that serves as a data source,
data link, or both, and provides for the data communications control function,
according to protocols.
device control. A SNAX/XF feature that provides programmatic interfaces by which
application processes executing in Tandem systems can control SNA devices residing
throughout an Expand network, without an SNA host system present.
DFC. Data flow control. This is one of the layers of the SNA protocol. It is part of the
half session.
dial–in. A SNAX/XF switched-line feature that allows the SNAX/XF line to condition
its hardware to receive incoming calls.
Distributed System Management (DSM). Tandem’s utility software designed to manage
distributed systems. It includes interfaces for subsystems as well as error message
handling. See also event management service. See also subsystem programmatic
interface.
domain. In SNA, a system services control point (SSCP) and the PUs, LUs, links, and
associated resources that the SSCP has the ability to control by means of activation
requests and deactivation requests.
DSM. See distributed system management. See also event management service. See
also subsystem programmatic interface.