Cisco CCNA Exam Tutorial: A Guide To RAM, ROM, NVRAM, and Flash

CCNA exam success depends on knowing the details,RAM is short for Random-Access Memory. RAM on
and nowhere is this more true than knowing thea Cisco router stores operational information such as
various components of a Cisco router. This is alsorouting tables and the running configuration file. RAM
where you can quickly start drowning in acronyms!contents are lost when the router is powered down or
The terms "RAM" and "ROM" probably aren't new toreloaded.
you, but keeping up with "what goes where" withNVRAM is non-volatile RAM. By "non-volatile", we
RAM, ROM, NVRAM, and Flash Memory can be quitemean that the contents of NVRAM are not lost when
a challenge! In this tutorial, we'll take a look at all four ofthe router is powered down or reloaded. Where RAM
these components and their contents.holds the running configuration file, NVRAM holds the
ROM stands for Read-Only Memory. ROM stores thestartup configuration file. If NVRAM is empty when the
router's bootstrap startup program, operating systemrouter reloads, you will be prompted to enter setup
software, and power-on diagnostic test programs (themode.
POST).Success on the CCNA exam depends on keeping
Flash memory is generally referred to as "flash" Thethese terms straight and knowing their contents. Know
Cisco Internetwork Operating System (IOS) imagesthe contents of each, pay special attention to what is
are held here. Flash is erasable and reprogrammablelost on a reload and what is not, and you're on your
ROM. Flash memory content is retained by the routerway to CCNA exam success!
on power-down or reload.