What is the working memory for a router that stores the running-configuration file, a copy of the IOS, the routing tables, and any associated data required by the routing process?

• A. RAM
• B. ROM
• C. NVRAM
• D. Flash

Answer: (A)

The running state of a router is kept in RAM, because this is the memory the device uses actively while operating. The running-configuration file needs to be writable and immediately accessible, the IOS image that is currently executing is loaded into memory for fast execution, and all routing tables plus the data the routing processes work with are stored there for quick updates and lookups. RAM is volatile, so its contents disappear when power is removed, which is appropriate for data that is refreshed or reloaded on boot. In contrast, ROM contains a basic or minimal IOS and boot code, NVRAM stores the startup-config, and Flash holds the IOS image and other files for long-term storage, not the active runtime state.