Abstract: A method uses circuitry in a data interface that provides telephony service over a high-speed network to detect the presence of a secondary source of VBH battery voltage on a tip-ring system. If a detected source other than the data interface is impressing battery voltage on the tip-ring system, the circuitry disconnects the data interface's battery source and produces a message that another source is VBH. The determination that another source is present may be based on a threshold value to account for noise.

Abstract: A software routine that writes downloaded updated operating system software over existing application code to flash memory of a cable modem in an inverted arrangement. If the download process is interrupted before the update can be verified, a pointer still points to the existing code to facilitate update-interruption recovery. After verifying a successful update, a new pointer is generated that points to the updated operating system. Then, updated application code can be downloaded and stored in the flash memory over the old operating system code.