Digital Link DL3800 DS1, Руководство пользователя

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G-16 DL3800 DS1 Inverse Multiplexer User Guide—February 1999
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S
SCR (Serial Clock Receive)
A unipolar clock from the DCE signal. A data port signal.
SCT (Serial Clock Transmit)
A unipolar clock from the DCE signal. A data port signal.
SCTE (Serial Clock Transmit External)
The clock signal is echoed from the DTE for the purpose of timing incoming
data on long cable runs.
scrambler
A device or software program that encodes data for encryption. It distorts a
voice or data conversation so that only another like device can Þgure out the
content of the message.
SD (Send Data)
A signal from DTE to DSU/CSU.
secondary channel
A subchannel derived from the main channel. It does not carry data messages
and is used for diagnostic or supervisory purposes.
serial transmission
A sequential transmission of bits constituting an entity of data over a data
circuit.
SES (Severely Errored Second)
A second during which 320 or more CRC violations or OOF events have
occurred (ESF framing only).
SG (Signal Ground)
A signal from DTE to DSU/CSU.
simplex current
One way transmission used by Telco to provide power to repeaters.
SLIP (Serial Line IP)
A TCP/IP protocol that allows IP packets to be transmitted over a serial link,
such as a dial-up or private telephone line.
SMDS (Switched Multimegabit Data Service)
A fast-packet technology based on the connection-less data networking
capability described in the IEEE 802.6 speciÞcation. The data format for SMDS
is Òcell oriented.Ó SMDS does not support voice.