To check your current version, log into your router's admin panel (typically found by entering 192.168.1.1 192.168.0.1 in your browser) and look for the Firmware Version under the status or advanced settings tab. Kaon CG3000 Firmware - vsociety - Vicarius
Updating the firmware on this device is generally an automated background process. You can identify when an update is occurring by looking at the indicator lights on the front panel: kaon cg3000 firmware update