Wise TSW200E1, Руководство пользователя

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TSW200E1
LAN ( Local Area Networks )
A computer network that spans a relatively small area. Most LANs are confined to a single
building or group of buildings. However, one LAN can be connected to other LANs over any
distance via telephone lines and radio waves. A system of LANs connected in this way is called a
wide-area network (WAN).
Link
Connection between two devices.
LOF ( Loss Of Frame )
FAS loss. This term is used at the ITU-T Recommendations G.826 and M.2100.
LOS ( Loss Of Signal )
This term is used at the ITU-T Recommendations G.826 and M.2100.
Modem
Contraction of the words Mod ulator and Dem odulator. It indicates a class of devices that
allow digital data to be transmitted over normal telephone lines, modulating the signal at the
transmit side and demodulating it at the receive side.
Synchronous/Asynchronous Mode
For the synchronous mode, data are transmitted according to a separate clock signal, which
is used at the reception to identify the data. In this case, the transmitter and receiver must be in sync.
For the asynchronous mode, there is no separate clock signal: the characters of any data are
preceded by start bits and followed by stop bits, which provide synchronism at the receive end.
ms
Millisecond; equivalent to a thousandth (10
-3
) of a second.
MFAS ( MultiFrame Alignment Signal)
Used at timeslot 16 for frame 0 for the 2 Mbps frames.
NFAS ( Non-Frame Alignment Signal)
These are the odd frames (for timeslot 0) that do not have the frame alignment signal for the
2 Mbps frames.
NMFAS ( Non MultiFrame Alignment Signal)
It does not posses the multiframe alignment signal for the 2 Mbps frames and it is associated
to the MFAS word (bits 5 to 8 of timeslot 16, frame 0). This word is only used for the PCM30 and
PCM30C standards.
PCM ( Pulse Code Modulation )
Short for p ulse c ode m odulation, a sampling technique for digitising analogue signals,
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