ADTRAN Express L128FP, User Manual

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Glossary
Glossary-10 Express L128FP User Manual 61202070L4-20
SPCS
Stored Program Controlled Switch. A digital switch that supports call
control, routing, and supplementary services provision under soft-
ware control. All ISDN switches are SPCSs.
spoofing
Spoofing reduces the required bandwidth by having devices, such as
bridges or routers, answer for the remote devices. This causes the re-
mote LAN to appear as if it is still connected to the LAN device even
though it is not. The spoofing saves the WAN bandwidth, because no
packet is ever sent out on the WAN.
synchronous
(1) The condition occurring when two events happen in a specific time
relationship with each other, both under control of a master clock; (2)
A method of data transmission requiring the transmission of timing
pulses to keep the sender and receiver synchronized in their commu-
nication used to send blocks of information. Synchronous data trans-
mission is used in high speed data circuits because there is less
overhead than asynchronous transmission of characters which con-
tain two extra bits per character to effect timing.
T1
Also T-1. A digital transmission link with a capacity of 1.544 Mbps. T1
uses two pairs of normal twisted wires. T1 normally can handle 24
voice conversations with each conversation being digitized at 64 kbps.
With more advanced digital voice encoding techniques, it can handle
more voice channels. T1 is a standard for digital transmission in
North America.
TA
Terminal Adaptor. A DCE that connects to the ISDN S-Interface and en-
ables non-ISDN terminal equipment to communicate over the ISDN.