Cisco BPX 8650, Руководство по установке и настройке

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Glossary
GL-16
Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
PBX
private branch exchange.
Digital or analog telephone switchboard, classified as customer premise equipment (CPE), used to
connect private and public telephone networks.
PCM
pulse code modulation.
The system for transmitting telephone signals digitally. Voice is sampled 8000 times per second and
converted to an 8-bit digital word.
PCR
peak cell rate.
The maximum rate for an ATM connection at which cells are allowed into the network.
PCS
port concentrator shelf.
The PCS is an external shelf that expands the capacity of the FRM card. The PCS is used with the
FRM-2 (IGX switch) card to 44 frame relay connections. The PCS connects to the FRI-2.X.21 back
card.
peak cell rate
See PCR.
peak information
rate
See PIR.
permanent virtual
connection or circuit
See PVC.
physical layer
convergence
protocol
See PLCP.
physical layer
protocol processor
See PLPP.
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.
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.
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.
PNNI
private network-to-network interface.
Private Network-to-Network Interface controller software that runs on the SES hardware platform.
The term PNNI controller and SES may be used interchangeably.