X25AM Configuration and Management Manual

Glossary
X25AM Configuration and Management Manual—523424-004
Glossary-3
communications line interface processor (CLIP)
communications line interface processor (CLIP). The major programmable device within
the ServerNet wide area network (SWAN) concentrator, providing link-level protocol
and a software interface to the host. The CLIP stores and implements specific
communications protocols.
communications subsystem. Collection of hardware and software that provides a specific
communications function (for example, communications between a NonStop NS-series
or NonStop S-series server and an X.25 network).
CONFTEXT file. On G-series and H-series RVUs, the CONFTEXT file consists of one or
two paragraphs: DEFINES (optional) and ALLPROCESSORS.
conversation mode. Data transmission mode for a terminal. Transmitted data messages
consist of single characters instead of groups of characters.
CUD. See call user data (CUD).
CUG. Closed user group. Optional network facility that restricts calls to members assigned
to a group.
Data Network Identification Code (DNIC). Part of an ITU-T numbering scheme that
provides each network with a unique address. The DNIC contains a three-digit data
country code (DCC) and a one-digit network identification (NI) code. See also X.121.
data packet. Packet that contains data.
DCE. Data circuit-terminating equipment. In the context of the X.25 standard, the network is
identified as a DCE. X25AM can be configured as either DCE or DTE. The term DCE is
also used to refer to a modem.
destination address. See called address.
device. Physical or logical system component. For X25AM, a line is a device defined in the
CONFTEXT file.
DISC. Disconnect. Link-level frame used for call disconnection.
DNIC. See Data Network Identification Code (DNIC).
D-series system. A system running a D-series version of the NonStop Kernel operating
system. A D-series system can have more than 256 concurrent processes in a CPU.
DSR. Data set ready. Signal coming from a modem which usually indicates to the computer
equipment that the modem is powered on.
DTE. Data terminal equipment. The user’s computer system; that is, equipment connected
by data circuit-terminating equipment (DCE) to telephone company lines or data
circuits. A DTE is usually a terminal or a computer. With X.25AM, the
NonStop NS-series or NonStop S-series server can function as either DTE or DCE.