Panasonic FP-D250 User Manual page 597

LAN Network Manager IBM's network management software for Token Ring
networks.
LAN Segment A part of a LAN that is separated from the rest by one or more bridges.
LAN Server IBM version of IBM LAN Manager.
LAP (Link Access Protocol) The Data Link or OSI Layer Two protocol specified by
the ITU-TS for the X.25 interface standard.
LAP-B: A link set-up routine to establish and maintain links between DCE and DTE.
Lap-D: The Layer Two protocol for an ISDN D-channel specified in the ITU-TS
recommendation Q.921. It is a framed, bit-oriented protocol similar to Lap and Lap-
B protocols specified for X.25 circuits. Lap-M: A variation of Lap-B used in the V.42
modem error control standard.
Laser A focused beam of light that is used in many imaging systems. Laser is an
acronym that stands for Light Amplification by Stimulated Emission of Radiation.
Latent Image A latent image is an image that is present but not yet visible. For
example, a latent image exists on exposed film that hasnít been processed. In
electrophotography, the latent image is composed of static charge present on the
photoconductive drum. The image only becomes visible after toner is applied.
Line driver A signal converter that conditions the digital signal transmitted by an
RS232 interface to extend reliable communication beyond the 50ft RS232 limit up to
several miles. It is a baseband transmission device.
Line turnaround The interval on a transmission link between the time one block of
data was sent and received and the time the next one can be sent.
Line signal standards In the US: T1 carries data at 1.544Mbit/s and has 24 voice
circuits; T1C 3.152 Mbit/s with 48 voice circuits; T2 6.312Mit/s with 96 voice circuits,
and T3, 44.736Mbit/s. In Europe, the standards are of the form En. E1 line speed is
2.048Mbit/s with 3C voice circuits; E2 is 8.448Mit/s with 120 voice channels. E3 is
34.368Mbit/s with 480 voice circuits. In the UK, E1 is often referred to as MegaStream,
a BT label for its 2Mbit/s leased circuits.
7-31