Specifications

Network Processing Engine Replacement Instructions 5
Network Processing Engine Description
• Cache memory
— The NPE-100, NPE-150, and NPE-200 have unified cache SRAM that functions as the
secondary cache for the microprocessor. (The primary cache is within the microprocessor.)
— The NPE-175 and NPE-225 have two levels of cache: a primary that is internal to the
processor and a secondary, 2-MB external cache that provides additional high-speed storage
for data and instructions.
— The NPE-300 has three levels of cache: a primary and a secondary cache that are internal to
the microprocessor, and a tertiary, 2-MB external cache that provides additional high-speed
storage for data and instructions.
• Two environmental sensors for monitoring the cooling air as it leaves the chassis
• Boot ROM for storing sufficient code for booting the Cisco IOS software; the NPE-175,
NPE-200, NPE-225, and NPE-300 have boot ROM
The network processing engines perform the following system management functions:
• Sending and receiving routing protocol updates
• Managing tables, caches, and buffers
• Monitoring interface and environmental status
• Providing Simple Network Management Protocol (SNMP) management through the console and
Telnet interface
• Accounting for and switching of data traffic
• Booting and reloading images
• Managing port adapters (recognition and initialization during online insertion and removal)
Figure 1 shows the NPE-100, Figure 2 shows the NPE-150, Figure 3 shows the NPE-175, Figure 4
shows the NPE-200, Figure 5 shows the NPE-225, and Figure 6 shows the NPE-300.
Figure 1 NPE-100
H8822
System
controller
Temperature
sensor
Temperature
sensor
Handle
Midplane
connectors
U12
Bank 1
DRAM SIMMs
U4
U25
U18
R4700
microprocessor
Captive
installation
screw
Bank 0
NETWORK PROCESSING ENGINE-100