Router Memory
Cisco 1700 Router Hardware Installation Guide
1-8
Router Memory
This section describes the types of memory stored in the router and how to find out how
much of each type of memory is stored in the router.
For instruction on how to upgrade memory in the router, refer to the “Installing and
Upgrading RouterMemory” appendix later in this guide.

Types of Memory

The Cisco1700 router has the following types of memory:
•Dynamic random-access memory (DRAM)—This is the main storage memory for the
router. DRAM is also called working storage and contains the dynamic configuration
information. The Cisco 1700 router stores a working copy of CiscoIOS software,
dynamic configuration information, and routing table information in DRAM.
•Nonvolatile random-access memory (NVRAM)—This type of memory contains a
backup copy of your configuration. If the power is lost or the router is turned off, this
backup copy enables the router to return to operation without reconfiguration.
•Flashmemory—This special kind of erasable, programmable memory contains a copy
ofthe Cisco IOS software. The Flash memory structure can store multiple copies of the
CiscoIOS software. You can load a new level of the operating system in everyrouter in
yournetwork and then, when convenient, upgrade the whole network to the new level.
The Flash memory on the Cisco 1700 router is stored on mini-Flash modules.