Configuring Systems for Terminals, Printers, and Other Serial Devices (32022-90057)

Glossary
DCE
Glossary
249
computer network A group of computer systems
connected in such a way that they can exchange
information and share resources.
configuration 1) The way in which computer
equipment is physically interconnected and set up to
operate as a system. 2) The layout of the computer
system, including the MPE table, memory, and
buffer sizes, that tells which peripheral devices are
(or can be) connected to the computer and how they
can be accessed. 3) The process of defining the
characteristics of a network in software.
For MPE/iX-based computers, the operating systems
are configured through use of the SYSGEN utility.
Next, the Datacommunications and Terminal
Subsystem (DTS) link is configured by using
NMMGR (running on the host) and can, in addition,
be configured using the OpenView DTC Manager
software (running on the OpenView Windows
Workstation) depending on the type of network
management you use.
A system that is to run network services
(NS 3000/iX) is configured through use of NMMGR.
Access to X.25 is configured in two parts. The X.25
MPE/iX System Access software is configured on the
host through use of NMMGR. The DTC/X.25
Network Access software residing on the DTC is
configured at the OpenView Windows Workstation
through use of the OpenView DTC Manager.
configuration file The configuration file contains
the information that the network needs in order to
operate. This file also contains information
necessary for link- level and NetIPC logging. The
only file name that the system recognizes is
NMCONFIG.PUB.SYS
control-X echo Three exclamation marks (!!!)
output to the terminal screen when the cancel
character (normally
[CTRL]-X
) is entered.
control-Y trap A user-written procedure to which
control is passed when the subsystem break
character (normally
[CTRL]-Y
) is entered during
execution of a program with subsystem break
enabled.
cross-validate The process of assuring that
information contained in two locations is consistent
where it is imperative that it be consistent. For
example, an automatic cross-validation occurs when
you enter SYSGEN to assure that information
contained in NMCONFIG.PUB.SYS agrees with system
configuration data.
CSMA/CD Carrier Sense Multiple Access with
Collision Detect, transmission access method used
by the IEEE 802.3 LAN standard.
CSN See circuit-switching network.
CTB The cache transfer bus in the backplane of an
HP e3000.
CUG See closed user group.
D
data Basic elements of information that can be
processed or produced by a computer.
Datacommunications and Terminal Controller
See DTC.
datagram A self-contained packet that is
independent of other packets. It does not require an
acknowledgment and it carries information which is
sufficient to route it from one DTE to another DTE
without relying on earlier exchange between the
DTEs.
data overrun Transmitted data that is sent faster
than the receiving equipment can receive it. The
resultant overflow data is lost. See also flow
control.
Datapac The national public PSN of Canada.
Datex-P The national public PSN of West Germany.
D bit Delivery confirmation bit. Used in the X.25
protocol, the setting of the D bit in DATA packets
indicates whether delivery acknowledgment of the
packet is required from the local DCE or from the
remote DTE. It therefore allows the choice between
local and end-to-end acknowledgment.
DCE Data circuit-terminating equipment. The
interfacing equipment required in order to interface
to data terminal equipment (DTE) and its
transmission circuit. Synonyms: data
communications equipment, dataset. A modem is an
example of a DCE.