NS3000/iX NMMGR Screens Reference Manual - Edition 9 (36922-90040)

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network.
topology The physical arrangement of
nodes in a network. Some common
topologies are bus, star, and ring.
Transpac The national public PSN of
France.
Transmission Control Protocol TCP. A
network protocol that establishes and
maintains connections between nodes. TCP
regulates the flow of data, breaks messages
into smaller fragments if necessary (and
reassembles the fragments at the
destination), detects errors, and
retransmits messages if errors have been
detected.
transparent mode A data transfer
scheme in which only a limited number of
special characters retain their meaning
and are acted on by the system. All other
characters are considered to be data and
are passed through with no control actions
being taken.
transport, network Software that
corresponds to layers 4 and 3 of the OSI
network architecture model. It sends data
out over the communications link, receives
incoming data, and routes incoming or
outgoing data to the appropriate
destination node.
TTUTIL Also known as the Workstation
Configurator. A program, TTUTIL.PUB.SYS,
on the HP e3000 that is used to create and
modify terminal and printer type files.
Tymnet A proprietary public datanetwork
in the USA.
typeahead A facility that allows terminal
users to enter data before a read is actually
posted to the terminal.
U
UPS See uninterruptible power
supply.
unacknowledged frame number (K)
The number of frames that can be
transmitted without receiving an
acknowledgment from the destination
address. When this number (K) frame is
reached, the same K frames are
retransmitted.
unedited mode See transparent mode.
uninterruptible power supply A
hardware device that protects equipment
from power failures and contains an
internal storage battery to supply reserve
power.
V
V.24 The CCITT recommendation that
defines the function of the interchange
circuits between a DTE and a DCE.
validation The process of ascertaining
whether the network transport
configuration file has been correctly
configured. In guided NMMGR, you do this
by pressing the Validate Netxport key.
VAN Value-Added Network. A data
communication network that uses and pays
for facilities belonging to another carrier.
The value-added package is then sold to a
user.
VC See virtual circuit.
virtual circuit A logical association
between two physically separate DTEs.
virtual terminal A network service that
allows a user to establish interactive
sessions on a node.