Carrier Access Network Device Axxius 800, Руководство пользователя

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Axxius 800 - Release 2.2 Glossary - 3
Glossary
bipolar
bipolar
The predominant signaling method used for digital transmission
services, such as DDS and T1. The signal carrying the binary value
alternates between positive and negative. Zero and one values are
represented by the signal amplitude at either polarity, while no-value
"spaces" are at zero amplitude.
Bipolar
Violation (BPV)
The presence of two consecutive "one" bits of the same polarity on the T
carrier line.
bit
Contraction of the words "binary" and "digit".
Bit Error Rate
Test (BERT)
A test that reflects the ratio of errored bits to the total number transmitted.
Usually shown in exponential form (10^-6) to indicate that one out of a
certain number of bits are in error.
bit robbing
Telephony coined phrase to describe a transmission process. The
technique in T1 multiplexing in which the least significant bit (bit 8) of
each byte in selected frames is "robbed" from being used to carry
message information, and instead is used to carry signaling information.
bps
Bits per second
BPV
Bipolar Violation.
BRI
Basic Rate Interface (2b+d) in ISDN.
bridge
A bridge is any hardware device that connects two physically distinct
network segments, usually at a lower network layer than would a router,
however the two terms are often interchanged. A device that connects
two local-area networks (LANs), or two segments of the same LAN. The
two LANs being connected can be alike or dissimilar. Unlike routers,
bridges are protocol independent. They simply forward packets without
analyzing and re-routing messages. Consequently, they’re faster than
routers, but also less versatile.