Cisco BPX 8600 Series, Руководство по установке и настройке

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Glossary
16
Cisco BPX 8600 Series Installation and Configuration
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
PCS (Port
Concentrator Shelf)
The PCS is an external shelf that expands the capacity of the FRP card. The PCS is sued with the
FRM-2 (IGX switch) card to 44 frame relay connections. The PCS connects to the FRI-2.X.21
backcard.
PIR (Peak
Information Rate)
The peak level in bits per second allowed for a frame relay connection.
PLCP (Physical Layer
Convergence
Protocol)
A protocol defined for use with Switched Megabit Data Service. Used on DS3 ATM trunks in the BPX
switch.
PLPP (Physical Layer
Protocol Processor)
A custom VLSI processor used in the T3 ATM port interface of the BPX BNI card to handle the coding
and decoding of the PLCP bit structure. Functions handled by the PLPP include header check
sequence generation and checking, DS3 framing, and optional payload scrambling/descrambling.
plesiochronous
network
A network where there is more than one source of network timing. The multiples sources must be
operating at the same frequency but are not phase locked (synchronous) with each other.
PNNI
Private Network-to-Network Interface controller software that runs on the SES hardware platform.
The term PNNI controller and SES may be used interchangeably.
Port
Refers to a signal connection on a data back card that interfaces to a customer circuit or data device.
The number of ports on a card ranges from 1 to 8 depending on the particular card type.
“Port” is synonymous with “Interface.”
The VSI makes no distinction between trunk ports and end-point ports.
PRI (Primary Rate
Interface)
An ISDN interface to primary rate access. Primary rate access consists of a single D channel for
signalling and 23 (T1) or 30 (E1) B (bearer) channels for user data. A PRI is typically carried on T1
or E1 facilities.
privilege level
A level between 1 and 6 that is assigned to each command. Each operator is assigned a privilege level
by the system administrator. The operator may only access and execute commands equal to or lower
than his or her own privilege level. Level 1 is the highest and level 6 is the lowest.
PVCs
Permanent Virtual Connections (circuits). Connections that are assigned but not connected until data
is sent, thereby not using bandwidth when idle.
P