Panasonic FP-D350, Руководство пользователя

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Glossary
of Terms
P
Packet A collection of bits, including the address, data and control, that are switched
and transmitted together. The terms frame and packet are often used synonymously.
Packet Buffer Memory space reserved for storing a packet awaiting transmission or
for storing a received packet.
Packet Switching A method of switching data in a network. Individual packets of a
set size and format are accepted by the network and delivered to their destination.
The sequence of packets is maintained, and destination established, by the exchange
of control information (also contained in the packets) between the sending terminal
and the network before the transmission starts. The network is open to all users, all
the time, with packets from the various nodes being interleaved throughout the
network. The packets can be sent in any order, as the control information sent at the
beginning of the transmission ensures they are interpreted in the correct order at the
receiving end. Because each packet carries its own control instructions, it can use
any route to reach its destination. The link lasts only as long as the transmission. An
ITU-TS standard for packet switched networks information.
Page Buffering The ability to spool an entire image to disk and print continuous.
Parallel The transmission of bits over multiple wires at one time. Accomplished by
devoting a wire for each bit of a byte. Parallel data transmission is a very fast, but
usually happens only over short distances typically under 500 feet because of the
need for huge amounts of cable. Most often used in computer-to-printer, and scanner-
to-computer applications.
Parity Used in error correction. A separate bit the parity bit is added and manipulated
so that the number of 1s is odd for odd parity or even for even parity. If the number
of bits sent donít conform to the parity, the software detects an error.
PDL/PCL Refers to the page description language or printer control languages that
are included as standard. A PDL is computer programming language that describes
text and graphics for use by the printer. Examples of page description languages
include Adobe Systems PostScript Level 1, 2 and 3. Note that if a printer uses
PostScript interpreter or PCL emulation, instead of PostScript will be listed under
emulation's for that printer. Printer control languages such as Hewlett-Packards
PCL are also listed here.