Greening the NetFPGA Reference Router

Feng Guo,Martin Collier,Mei Song,Xiaojun Wang,Olga Ormond,Yifei Wei

doi:10.3390/en9070500

Feng Guo, Martin Collier + Show 4 more

Open Access

https://doi.org/10.3390/en9070500

Copy DOI

Abstract

Energy efficiency is an important criterion in the design of next generation networks for both economic and environmental concerns. This paper presents an energy-efficient router that is able to dynamically adapt its routing capability in response to real-time traffic load, achieving energy proportional routing. The NetFPGA reference router, which operates at one of two frequencies (125 MHz or 62.5 MHz), requires a board reset to switch frequencies. We have modified the reference router to allow dynamic switching among five operating frequencies. Experiments with real traces indicate that, compared to the reference router, a 10% power reduction can be achieved through dynamic frequency scaling. When the router is further modified to support green traffic engineering and Ethernet port shut-down, power consumption can be reduced by 46% while maintaining the required quality of service. This allows the router to meet the instantaneous performance requirements while minimizing power dissipation. Similar results can be expected when these general power-saving principles are applied in future commercial routers.

Highlights

In information and communications technology (ICT) networks, the traditional design of network devices tends to primarily emphasize performance in terms of working speed
For a given NetFPGA board, Pq, C and V are fixed values, and A is affected by the number of active ports, the instantaneous traffic bit rate and the forwarding packet size
The 3.3-V and 5-V pins of the Peripheral Component Interconnect (PCI) bus extender are used to measure the overall current drawn by the 3.3-V and 5-V powered components on the NetFPGA board mounted on the PCI bus extender

Summary

Introduction

In information and communications technology (ICT) networks, the traditional design of network devices tends to primarily emphasize performance in terms of working speed. The network devices were designed to translate improvements in digital circuits and operating frequency into performance, such as maximizing the router capacity at the cost of the highest and constant power consumption regardless of the traffic load. A detailed report [3] estimated that a huge increase in overall network power consumption is predicted for European ISPs from around 21.4 terawatt-hours (TWh) in 2010 to around 35.8 TWh in 2020, if no green technologies are adopted. Such a huge increase in power consumption could result in billions in energy costs. In 2010, a study [5] indicated that the ICT industry contributed about 2% of global CO2 emissions, which is equivalent to the entire airline industry

Methods

Results

Conclusion