Hierarchical Power Management Architecture and Optimal Local Control Policy for Energy Efficient Networks
"Since energy efficiency has become a significant concern
for network infrastructure, next-generation network devices are
expected to have embedded advanced power management capabilities.
However, how to effectively exploit the green capabilities is
still a big challenge, especially given the high heterogeneity of devices
and their internal architectures. In this paper, we introduce a
hierarchical power management architecture (HPMA) which represents
physical components whose power can be monitored and
controlled at various levels of a device as entities. We use energy
aware state (EAS) as the power management setting mode of each
device entity. The power policy controller is capable of getting information
on how many EASes of the entity are manageable inside
a device, and setting a certain EAS configuration for the entity. We
propose the optimal local control policy which aims to minimize
the router power consumption while meeting the performance constraints.
A first-order Markov chain is used to model the statistical
features of the network traffic load. The dynamic EAS configuration
problemis formulated as aMarkov decision process and solved
using a dynamic programming algorithm. In addition, we demonstrate
a reference implementation of the HPMA and EAS concept
in a NetFPGA frequency scaled router which has the ability of toggling
among five operating frequency options and/or turning off
unused Ethernet ports."