Lucent Technologies Release 8.2 manual Lap-D

LAN Glossary

L

LAN

See local area network.

LAN emulation (LANE)

A technique that lets ATM networks communicate with Ethernet LAN cards. ATM service is not widely available at the desktop and ATM interface cards are expensive, so ATM networks usually emulate LANs when communicating with user terminals. Typically, a LAN-emulation configuration server (LECS) keeps track of the relationships between ATM-network addresses and IP addresses on the LAN. Each ATM card is then treated as a client of a LAN-emulation server, which connects the ATM cards to the LAN cards on the user terminals.

LAP-D

See link-access procedure on the D-channel (LAPD).

LECS (LAN-emulation configuration server)

See LAN emulation (LANE).

LES (LAN-emulation server)

See LAN emulation (LANE).

line coding

Line coding is the data format that lets either end of a communications channel correctly interpret messages from the other. Line coding systems specify the voltage levels and patterns that represent binary digits (1s and 0s), based on the requirements of the transmission network. The AT&T network has two: it demands that the net voltage on the line equal 0 volts DC and it demands a minimum Open System Interconnect (OSI) Model. The T-carrier system meets the first requirement by using a bipolar line-coding scheme called Alternate Mark Inversion (AMI). It meets the second with one of several supplementary coding schemes, including ZCS, Bipolar 8 Zero Substitution (B8ZS), and High Density Bipolar 3-Bit Substitution (HDB3).

line compensation

An allowance for pulse distortions in the cable that connects the MMCX server to the first channel service unit (CSU) on the PRI span. It is proportional to the length of the cable. T1 circuit packs adjust the outgoing signal so that it arrives at the far end without distortion.

link

A transmitter-receiver channel that connects two systems.

		Administration for Network Connectivity
478	CID: 77730	555-233-504 — Issue 1 — April 2000