Cisco XR 12404 - Manual (Page 18)

Chapter 1 Cisco XR 12404 Router Overview
Route Processor
1-4
Cisco XR 12404 Router Installation Guide
OL-13830-02
Route Processor
The route processor for the Cisco XR 12404 router is the Performance Route
Processor (PRP-2). For detailed information about the PRP-2, refer to the Cisco
document, Performance Route Processor Installation and Configuration Guide.
The PRP-2 and PRP-3 performs the following primary functions:
• Executes routing protocol stacks
• Performs all protocol communications with other routers
• Builds and distributes forwarding information to all line cards
• Uploads the operating system software images to all installed line cards
during power-on
• Provides out-of-band system console and auxiliary ports and an Ethernet port
for router configuration and maintenance
• Monitors and manages the power and temperature of system components
such as line cards, power supplies, and fans
The Cisco PRP-2 and PRP-3 delivers all these functions with enhanced
performance and capabilities. It also delivers the following feature enhancements
(depending on the software version running):
• 2 Ethernet management ports
• Hard-drive support (optional part)
• BITS input ports
• 1 GB compact image Flash memory support (optional part)
• Memory scalability up to 4 GB with PRP-2 and up to 8 GB with PRP-3.
The PRP-2 and PRP-3 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. The MBus connection allows the PRP-2 and PRP-3 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).
todd.book Page 4 Monday, March 16, 2009 2:47 PM