Cisco BPX 8600 Series, Руководство по установке и настройке

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4-4
Cisco BPX 8600 Series Installation and Configuration
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
Chapter 4 BNI (Trunk) Cards
Broadband Network Interface Cards (BNI-T3 and BNI-E3)
•
Extracts receive timing from the input framing and makes it available for node timing. Line can
operate in looped timing mode.
• Recovers clock and data from the bipolar B3ZS (T3) or HDB3 (E3) line signal and converts data
to unipolar.
Figure 4-2 Simplified BNI-T3, BNI-E3 Block Diagram
Some of the functions performed by the PLPP in the BNI-3T3 include:
• PLPP— Receiver Side
–
Provides frame sync for either the M23 or C-bit parity frame format.
– Provides alarm detection and accumulates B3ZS code violations, framing errors, parity errors,
C-bit parity errors, and far end bit error (FEBE) events.
– Detects far end alarm channel codes, yellow alarm, and loss of frame.
–
Provides optional cell descrambling, header check sequence (HCS) error detection, and cell
filtering.
– Small receive FIFO buffer for incoming cells.
• PLPP—Transmitter Side
–
Inserts proper frame bit sequence into outgoing bit stream.
– Inserts proper alarm codes to be transmitted to the far end.
– Provides optional ATM cell scrambling, HCS generation and insertion, and programmable null
cell generation.
–
Small transmit FIFO for outgoing cells.
StrataBus backplane
8153
DS3 #1
DS3 #2
DS3 #3
E3 #1
E3 #2
E3 #3
BNI-3E3 only
BNI-3T3 only
Comm.
bus
interface
Control
& admin.
processor
Network
address
table
Queue service
engine #1
DS3 function
block (PLPP)
G.832 framer
E3 xmtr/rcvr
G.832 framer
E3 xmtr/rcvr
G.832 framer
E3 xmtr/rcvr
DS3 function
block (PLPP)
DS3 function
block (PLPP)
Queue service
engine #2
Queue service
engine #3
Serial
interface
module
(SIM)