Cabletron Systems Netlink FRX8000, Руководство пользователя

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glo-8 FRX8000 3. 0 User G uide, Rev 02
P
Packet
is a group of data and control signals transmitted as a composite whole across a
packet-switching network.
Packet Switching
is the breaking up of data into smaller pieces and the transmission of these pieces over
a network via X.25.
PAD
stands for “packet assembler/disassembler,” which allows a non-X.25 device to access
an FRX8000 or N74/7500 node, by converting its protocol to the X.25 packet mode
protocol, and vice versa. Cabletron offers integral async, SNA, and BSC PADs in the
FRX8000. (BSC is not supported in the N74/7500.)
PDN
stands for “public data network,” which is a network operated by common carriers or
telecommunications administrations for the purpose of providing data transmission
capabilities to the public.
Physical DCE/DTE
see “DCE” and “DTE.”
Port
is an entry or exit point for node and NMP data transmission. Each FRX8000 LP (line
processor) has four or eight physical ports, depending on the number of attached Line
Interface Cards. Additionally, each physical X.25 or frame relay port supports up to
56 logical ports. (Each logical port on a physical port uses a different logical channel,
or LCN.)
The AST LP supports four physical ports, with an additional four async ports available
by attaching a daughter card.
LAN adapter cards support one port each.
Protocol
is an agreement on format, meaning, and relative timing of information exchanged
between two communications devices.
Prompt
is a word or words, displayed on the screen, that require a response from the operator
before anything else will happen in the operation that is being performed.
Public Data Network
see “PDN.”
PVC
stands for “permanent virtual circuit,” which is a permanent logical connection
between two subscribers, analogous to a leased line. Transmission of packets on a
PVC needs no call setup or call clearing.