Cisco Systems 7401ASR manual Rear View, System Board

Hardware Overview

Rear View

Figure 1-3 Cisco 7401ASR Router—Rear View

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Chapter 1 Overview and Parts Installation

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Fan vent

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Grounding connector

The rear of the Cisco 7401ASR router has five fan airflow vents and the chassis grounding connector that provides a chassis ground connection for ESD equipment or a two-hole grounding lug. (See Figure 1-3.)

Five internal fans draw cooling air into the chassis and across internal components to maintain an acceptable operating temperature. (See Figure 1-3.) The five fans are located at the rear of the chassis.

System Board

Internally, the system board contains the following components:

•SDRAM memory that is available in three options: 128, 256, or 512 MB DIMM

•Processors

–Reduced instruction set computing (RISC) RM7000 microprocessor that operates at an internal clock speed of 375 MHz. The RM7000 processor maintains and executes the system management functions for the Cisco 7401ASR router. The processor also performs some memory and environmental monitoring functions.

–The Parallel eXpress Forwarding (PXF) processor enables parallel IP multipacket processing functions, working with the Route Processor to provide accelerated packet switching, as well as accelerated IP Layer 3 feature processing.

•System controller

The system controller provides hardware logic to interconnect the processors, SDRAM, and the PCI buses. The Cisco 7401ASR router has one system controller that provides processor access to the two PCI buses. The system controller also allows the port adapter access to SDRAM.

•Cache memory

The processor has three levels of cache: primary and secondary cache that are internal to the microprocessor with secondary unified cache for data and instruction, and tertiary, 2-MB external cache.

•Two environmental sensors for monitoring the internal temperature of the chassis

•Boot ROM for storing sufficient code for booting the Cisco IOS software

Cisco 7401ASR Installation and Configuration Guide

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