Introduction to WANS

Introduction to routers in a WAN

 

NVRAM has the following characteristics and functions:

Provides storage for the startup configuration file

Retains content when a router is powered down or restarted

 

Flash memory has the following characteristics and functions:

Holds the IOS image

Allows software to be updated without removing and replacing chips on the processor

Retains content when a router is powered down or restarted

Can store multiple versions of IOS software

Is a type of electrically erasable programmable read-only memory (EEPROM)

 

ROM has the following characteristics and functions:

Maintains instructions for power-on self test (POST) diagnostics

Stores bootstrap program and basic operating system software

Requires replacing pluggable chips on the motherboard for software upgrades

 

Interfaces have the following characteristics and functions:

Connect routers to a network for packet entry and exit

Can be on the motherboard or on a separate module