Router Installation Guide

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Cisco XR 12410 Router Installation Guide
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Chapter 1 Cisco XR 12410 Router Overview
Switch Fabric and Alarm Card Overview
Switch Fabric Card
The switch fabric cards augment the traffic capacity of the router. SFCs contain
switch fabric circuitry that can only carry user traffic between line cards or
between the RP and the line cards. SFCs receive all scheduling information and
the system clock signal from the CSCs.
Alarm Cards and Alarm Display
The two alarm cards (in the switch fabric and alarm card cage) provide several
functions:
• Supply +5 VDC to the MBus modules on router components (see AC and DC
Power Subsystems, page 1-5).
• Work in conjunction with the alarm display to monitor the system. The alarm
display (sometimes referred to as the alarm display card) is above the
horizontal cable management bracket (
Figure 1-7).