ADTRAN Express L1.5, User Manual

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Glosssary
61202192L1-1 Express L768/L1.5 User Manual 113
jitter
The slight movement of a transmission signal in time or phase that can intro-
duce errors and loss of synchronization for high-speed synchronous commu-
nications. See phase jitter.
LATA
Local Access and Transport Area. One of 161 local telephone serving areas in
the United States, generally encompassing the largest standard statistical met-
ropolitan areas. Subdivisions established as a result of the AT&T divestiture
that now distinguish local from long distance service. Circuits with both end-
points within the LATA (intraLATA) are generally the sole responsibility of
the local telephone company, while circuits that cross outside the LATA (in-
terLATA) are passed on to an interexchange carrier.
loopback
A diagnostic procedure where data is sent to the device being tested, and the
output of the device is fed directly back to its input, looped around, and the
returning data is checked against that which was sent.
Media Access Control (MAC)
As defined by the IEEE, the lower of the two sublayers of the OSI reference
model data link layer. The MAC sublayer is concerned with media access is-
sues, such as whether token passing or contention is used.
message
The Layer 3 information that is passed between the CPE and SPCS for signal-
ling.
multipoint line
A communications line having multiple cable access points.
Name Binding Protocol (NBP)
The AppleTalk transport-level protocol that translates a character string name
into the internet address of the corresponding socket client; NBP enables Ap-
pleTalk protocols to understand user-defined zones and device names by pro-
viding and maintaining translation tables that map these names to
corresponding socket addresses.
NAT
Network Address Translation occurs at the borders of stub domains. Its pur-
pose is to translate the IP address of passing packets by changing all references
of one IP address to another. Translation is performed as per RFC 1631.