A network-oriented power management architecture

This paper presents the proposal and implementation of a power management architecture for local area network environments. Our main goal is to contribute to more efficient use of electricity, reducing energy waste by facilitating the configuration of power policies and providing a means to automate their execution. The architecture we propose is based on the SNMP (Simple Network Management Protocol) framework. The management process is coordinated by a central element, which applies configurable power policies to computers and other electronic devices connected to the network, either in accordance to consumption preferences defined by the network administrator, or in response to changes in the supply of electricity, detected through monitoring of UPS (Uninterruptible Power Supply) devices. In the latter case, applying the preconfigured power policies allows the UPS to sustain power to essential parts of the network (e.g. servers) for a longer period of time. Alternatively, the definition of power policies can be based exclusively on administrative preferences, in which case the goal is to minimize consumption of electricity during non-business hours by shutting down inactive equipment or putting it in low-power modes. We have measured UPS autonomy during utility power outages and found that it can increase by a factor of 7 in a small network setup, by using the management system to automatically power off 90% of the computers. Potential economy resulting from the decrease in consumption during nonbusiness hours alone is estimated to be as high as US$ 36 per computer during the period of a year.