Standard IEEE 1394-1995, High Performance Serial Bus, has been ratified as a standard via the IEEE balloting process. An examination of the IEEE 1394-1995 standard by members of the personal computer industry has concluded IEEE 1394-1995 does not provide adequate guidance for how power is to be provided, used, or managed.

A supplement to IEEE 1394-1995 has been developed (Draft Revision 2.0 IEEE 1394a-2000) in which a more comprehensive definition of power distribution and management has been provided.

This document, "Power Specification, Part 1: Cable Power Distribution," is intended to provide further enhancement by providing specific implementation guidelines and more detailed clarification of the enhancements found in IEEE 1394a-2000 supplement.

This document (part 1 of a three part power specification) deals with distribution of power within a network of 1394 nodes. It defines the power and voltage levels expected from compliant power providers, places restrictions on the use of 1394 power and the quantity and type of 1394 connectors a node implementation may have.

Part 2 of this specification Suspend/Resume Mechanisms deals with the capabilities and implementation of low power bus states in IEEE 1394a-2000 compliant nodes (standby/resume/suspend).

Part 3 of this specification, Power State Management deals with the management of changing the various power states of the individual components which make up an IEEE 1394a-2000 node - specifically the controls and mechanisms to move between various power states, the selection of power providers and routing (distribution) of power.

Part 4 of this specification, Power Distribution Management deals with the management of delivering power to cable powered devices - specifically, how much power exists on the network, which nodes are consuming power and what is the power budget for newly connected devices that need power.