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Network Processing Engine and Network Services Engine Installation and Configuration
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Chapter 2 NPE-175 and NPE-225 Overview
NPE-175 and NPE-225 Description and Overview
• Boot ROM for storing sufficient code for booting the Cisco IOS software; the NPE-175 and
NPE-225 have boot ROM
Note Neither the NPE-175 nor the NPE-225 has packet SRAM.
System Management Functions
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 (including recognition and initialization during online insertion and
removal)
Terms and Acronyms
• Cache—Memory with fast access and small capacity used to temporarily store recently accessed
data; found either incorporated into the processor or near it.
• DIMM—dual in-line memory module
• DRAM—dynamic random-access memory
• Instruction and data cache—Instructions to the processor, and data on which the instructions work.
• Integrated cache—Cache that is built into the processor; sometimes referred to as internal cache.
Cache memory physically located outside the processor is not integrated, and is sometimes referred
to as external cache.
• OTP—one time programmable
• Primary, secondary, tertiary cache—Hierarchical cache memory storage based on the proximity of
the cache to the core of the processor. Primary cache is closest to the processor core and has the
fastest access. Secondary cache has slower access than primary cache, but faster access than tertiary
cache.
• RAM—random-access memory
• RISC—reduced instruction set computing
• ROM—read-only memory
• SIMM—single in-line memory module
• SDRAM—synchronous dynamic random-access memory
• SDRAM-fixed—SDRAM of a fixed size or quantity; can be replaced, but not upgraded
• SODIMM—small outline dual in-line memory module