SNAX/HLS Diagnosis and Support Manual

Glossary
104706 Tandem Computers Incorporated Glossary–9
Systems Network Architecture Communications Services/Extended Facility (SNAX/XF). A
Tandem software product that provides a gateway between Tandem NonStop systems
and SNA systems and devices. With SNAX/XF, Tandem systems can function as fully
integrated components of an SNA network. SNAX/XF allows SNA devices attached
to a NonStop system either directly or through a switched line to use Tandem
applications. SNAX/XF provides device control, session passthrough, and
application–to–application communication.
System Services Control Point (SSCP). The focal point within an SNA network for
managing the configuration, coordinating network–operator and problem-
determination requests, and providing directory support and other session services for
the users of the network. Multiple SSCPs, cooperating as peers, can divide the
network into domains of control, with each SSCP having a hierarchical control
relationship to the PUs and LUs within its domain.
TACL. See Tandem Advanced Command Language.
Tandem Advanced Command Language (TACL). A Tandem product that provides the user
interface to the Tandem NonStop Kernel. The ITI protocol is used by the Tandem
command interpreter TACL.
UCW. Unit control word.
UCB. Unit control block.
VTAM. Virtual telecommunications access method.
X.25. A CCITT recommendation for the interface between data terminal equipment
and packet-switching networks; it is also referred to as Recommendation X.25.
XID. Exchange identification.