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Plexus 9000 Planning and Engineering Guide
Quad OC12 Network Access Module
Section 130-120-750
Issue 2, May 28, 2004
Telica, Inc.
5-179
5.16.3 Theory
of
Operation
Each Quad ATM Network Access module has on-board circuitry for
connection to SONET ATM networks. These interfaces can run at
622Mbps, and carry ATM data. The module can be provisioned for OC-3,
OC-12, STM-1 or STM-4 depending upon the hardware version of the
module. Refer to
for a block diagram of the Quad ATM
Network Access module.
The Network Access modules must be installed in I/O-8 and I/O-10
(physical slots 8 and 14) because these slots contain four OC-12 midplane
ports and also buses between them that are necessary for fault event
switchover.
SERDES
to/from
SF-A
APC
PHAZIT
NACSTER
M
I
D
P
L
A
N
E
P480-AA
03-14-02
APC
APC
APC
SERDES
to/from
SF-B
CLOCK
CIRCUITRY
MEM BUS
CONTROLLER
PROCESSOR
and
MEMORY
AAL5
SAR
MEMORY
FRAMER
OPTICAL
XCVR
CLOCK
RECOVERY
OPTICAL
XCVR
CLOCK
RECOVERY
PHAZIT
Figure 5.16-2. Quad ATM Network Access Module Block Diagram
5.16.3.1
Optical Transceivers and Clock Recovery and Framer Circuitry
The Network Access module has four optical transceivers capable of 622
Mbps and four clock recovery units (CRUs). The transceivers are industry
standard 1310nm wavelength, Intermediate-Reach, Single-Mode, with
SC-type connectors.