Cisco 7206VXR - VPN Bundle Router, Руководство по установке

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Cisco 7206 Installation and Configuration Guide
OL-5102-02
Chapter 1 Product Overview
Field-Replaceable Units
•
Reduced instruction set computing (RISC) microprocessor
– The NPE-100 and NPE-150 have an R4700 microprocessor that operates at an internal clock
speed of 150 MHz.
–
The NPE-175 has an RM5270 microprocessor that operates at an internal clock speed of
200 MHz.
– The NPE-200 has an R5000 microprocessor that operates at an internal clock speed of
200 MHz.
–
The NPE-225 has an RM5271 microprocessor that operates at an internal clock speed of
262 MHz.
• System controller
–
The NPE-100, NPE-150, and NPE-200 have a system controller that uses direct memory access
(DMA) to transfer data between DRAM and packet SRAM on the network processing engine.
– The NPE-175 and NPE-225 have one system controller that provides processor access to the two
midplane and single I/O controller PCI buses. The system controller also allows port adapters
on either of the two midplane PCI buses to access SDRAM.
•
Upgradable memory modules
– The NPE-100, NPE-150, and NPE-200 use DRAM for storing routing tables, network
accounting applications, packets of information in preparation for process switching, and
packet buffering for SRAM overflow (except in the NPE-100, which contains no packet
SRAM). The standard configuration is 32 MB, with up to 128 MB available through single
in-line memory module (SIMM) upgrades.
–
The NPE-175 and NPE-225 use SDRAM for providing code, data, and packet storage.
• Packet SRAM for storing packets of information in preparation for fast switching
–
The NPE-100 does not have packet SRAM.
– The NPE-150 has 1 MB of SRAM.
–
The NPE-175 does not have packet SRAM.
– The NPE-200 has 4 MB of SRAM.
–
The NPE-225 does not have packet SRAM.
• 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.
•
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,
and NPE-225 have a boot ROM