is often proprietary or carrier-specific, you won't usually find a "one-click" universal download. To find the correct link, you should: How to Check Modem Firmware - CenturyLink
Flip the device over. Look for a sticker that includes: mkey router modem v849 link download
: Check the sticker on the back of the modem for the exact hardware version to ensure you download compatible firmware. is often proprietary or carrier-specific, you won't usually