Panasonic FP-D250 User Manual page 569

Asynchronous communications A method of transmitting data in which each
transmitted character is sent separately. The character has integral start and finish
start and stop bits so that the character can be sent at an arbitrary time, and separate
from any other character. It is the most rudimentary type of communication as the
originating and receiving machines do not have to be synchronized. Cheap, reliable
and common among PCs and minicomputers, its disadvantage is the large number
of extra bits needed for the data to be interpreted.
ATM (Asynchronous Transfer Mode) A cell- based data transfer technique in which
channel demand determines packet allocation. ATM offers fast packet technology,
real time, demand led switching for efficient use of network resources. It is also the
generic term adopted by ANSI and the ITU-TS to classify cell relay technology within
the realm of broadband WANs, specifically B-ISDN. In ATM, units of data are not
time related to each other and, as part of the B-ISDN standard, is specified for digital
transmission speeds from 34Mbit/s to 622Mbit/s. IBM currently offers ATM at a non
standard 25Mbit/s format. ATM will be the high band width networking standard of
the decade.
Attenuation The weakening of transmitted signals as they travel away from their
point of origin. Amplifiers can recharge the signal up to a point.
Autochanger A device that holds multiple optical discs and one or more disk drives,
and can swap discs in and out of the drives as needed. This may also be referred to
as a jukebox.
AUI (Attachment Unit Interface) The IEEE 802.3 specified cable and connector used
to attach devices to a MAU. Defined in Section 7 of the 802.3 standard.
Automatic Emulation Switching A printer with this feature automatically accepts a
print job (data) in the emulation it is sent in (PCL5e for instance) without requiring the
user to manually set the printer to accept data for this emulation.
Auxiliary Storage External storage devices, such as disk drives, optical drives and
tape recorders.
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