Futurewei Futurewei Nvidia Nokia Reducing mankind's carbon footprint and making technology more sustainable are among the big challenges of our age. While networks are an enabler of applications that help to reduce this footprint, they also contribute to this footprint in no insignificant way themselves. Methods to make networking technology itself "greener" and to manage networks in ways that reduces their carbon footprint without impacting their utility therefore need to be explored. This document outlines a corresponding set of opportunities, along with associated research challenges, for networking technology in general and management technology in particular to become "greener", i.e. more sustainable, with reduced greenhouse gas emissions and carbon footprint.