Digital Link DL600E, Руководство пользователя

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Glossary
G-11
U
UA1 (Unframed All 1s)
ÑWhen the
DSU
loses its signal from the
DTE
device,
it generates a
NET UA1
Received Alarm to the E1 network.
V
V.35
Ñ
A CCITT
standard for the trunk interface between a network access
device and a packet network. It deÞnes signaling for data rates greater than
19.2
Kbps.
V.52
Ñ Terminal emulation standard. CCITT standard
(1976)
for various loop-
back tests that can be incorporated into modems for testing the telephone cir-
cuit and isolating transmission problems. Operating modes include local and
remote digital loopback and local and remote analog loopback.
V.54
Ñ
A CCITT
standard for loop test devices in modems. It deÞnes local and
remote loopbacks.
X
X.21
Ñ An interface between data terminal equipment
(DTE)
and data circuit-
equipment
(DCE)
for synchronous operation on public data networks. Also, a
CCITT
standard protocol for a circuit switching network.