Patent ID: 7013399

Claim:
A network device including: a first input voltage and one or more of second input voltages derived from an AC mains, at least one of said second input voltages providing power while said mains AC is present and having a loss of mains power signaling value when said mains AC is not present, whereby after the removal of said mains AC, said at least one second input voltage is at said loss of mains power signaling value while said first input is maintained for a holdup time thereafter; a primary communications interface powered by said first input voltage; one or more secondary communications interfaces, at least one said secondary communications interface powered by said one or more second input voltages providing power; a CPU powered by said first input voltage and coupled to said primary communications interface and forming messages which are sent over said primary communications interface, said CPU having a power fail input and sending a power fail message over said primary communications interface when said power fail signal input is asserted; where said power fail input is asserted when one or more of said secondary input voltages is at said loss of mains power signaling level.