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ADTRAN Express 4100 User Manual

Page 194

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Glossary

Glossary-4

Express 4100/4110 User Manual

61200176L2-1

arrangements and defines a limited set of standard, multipurpose interfaces for equip-

ment vendors, network providers, and customers. Interworking with a public

switched telephone network is retained.

jabber

An error condition in which a network device continually transmits garbage onto the

network. In IEEE 802.3, a data packet whose length exceeds that prescribed in the stan-

dard.

jitter

The slight movement of a transmission signal in time or phase that can introduce errors

and loss of synchronization for high-speed synchronous communications. See phase

jitter.

LATA

Local Access and Transport Area. One of 161 local telephone serving areas in the Unit-

ed States, generally encompassing the largest standard statistical metropolitan 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 (intraLA-

TA) are generally the sole responsibility of the local telephone company, while circuits

that cross outside the LATA (interLATA) 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 issues, such as whether

token passing or contention is used.

message

The Layer 3 information that is passed between the CPE and SPCS for signalling.

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 AppleTalk protocols

to understand user-defined zones and device names by providing and maintaining

translation tables that map these names to corresponding socket addresses.

NAT

Network Address Translation occurs at the borders of stub domains. Its purpose 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.