ADTRAN Express L128T S User Manual page 185

service advertising protocol (SAP)
An IPX protocol through which network resources such as
servers become known to clients.
serving area
Region surrounding a broadcasting station where signal
strength is at or above a stated minimum. The geographic
area handled by a telephone central office facility. Generally
equivalent to a LATA.
SNMP
Simple Network Management Protocol. SNMP provides a
means to monitor and set network configuration and runtime
parameters.
spanning tree
A loop-free subset of the topology of a network.
SPCS
Stored Program Controlled Switch. A digital switch that sup-
ports call control, routing, and supplementary services provi-
sion under software 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 remote 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 spe-
cific 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 re-
ceiver synchronized in their communication used to send
blocks of information. Synchronous data transmission is used
in high speed data circuits because there is less overhead than
asynchronous transmission of characters which contain 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 normal-
ly 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.
61202070L3-20 Express L128T S/T User Manual
Glossary
Glossary-7