Specifications

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Cisco MGX 8800/8900 Series Software Configuration Guide
Release 5.1, Part Number OL-6482-01, Rev. A0, January 25, 2005
Chapter 2 Configuring General Switch Features
Configuring Clock Sources
Note When NCDP is enabled, your manual configuration is disabled, and vice versa. When you disable NCDP,
your node reverts back to any manual clock configuration that was previously done on the node. If you
re-enable NCDP after disabling it, your switch will remember your last NCDP configuration and use that
unless you change it.
Both clock source options can use built-in hardware ports designed for Building Integrated Timing System
(BITS) clock sources. Figure 2-3 shows how BITS clock sources connect to the PXM45 UI-S3 back
card. Figure 2-4 shows how BITS clock sources connect to the PXM1E UI-S3/B back card.
The clock source ports on the UI-S3 and PXM-UI-S3/B cards can be used to receive clock signals from
either T1 or E1 lines; the card does not support both line types simultaneously. These clock ports support
stratum levels 1 to 3.
Note The PXM45 and PXM1E cards support T1 data (1.544Mbps) and E1 data (2.048Mbps) clock sources,
and the PXM1/B supports both T1 and E1 data types and an E1 sync (2.048MHz) line as a clock input.
The E1 sync line is not supported on switches with PXM45 and PXM1E cards.
Figure 2-3 BITS Clock Source Ports on PXM-UI-S3 Back Card
PXM
UI-S3
C
P
M
P
A
L
1
N
L
2
N
A
L
A
A
R
M
46143
c
L
K
1
c
L
K
2
port 35
port 36