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CiscoXR 12406 Router Installation Guide
OL-13831-01
Chapter1 Cisco XR 12406 Router Overview
Physical and Functional Description
The Cisco PRP-2 delivers all these functions with enhanced performance and
capabilities. It also delivers the following feature enhancements (depending on
the software version running):
•Gigabit Ethernet management port
•Hard-drive support (optional part)
•BITS input ports
•1 GB compact image Flash memory support (optional part)
•Memory scalability up to 4 GB
The PRP-2 communicates with the line cards either through the switch fabric or
through the MBus. The switch fabric connection is the main data path for routing
table distribution as well as for packets that are sent between the line cards and
the PRP-2. The MBus connection allows the PRP-2 to download a system
bootstrap image, collect or load diagnostic information, and perform general,
internal system maintenance operations.
The PRP-2 can be designated as either the Designated System Controller (DSC)
or the Secure Domain router (SDR).
The Designated System Controller (DSC) performs the following funct ions:
•Implements control plane operations for the chassis
•Monitors temperature and voltage
•Monitors line cards
•On boot up, the first card to become active is designated as the DSC.
The Secure Domain Router (SDR) controls domain security features independent
of any other SDRs on the network.