Energy-efficient data transfer: Bits vs. atoms
Ivana Marincic, Ian T Foster · 2016
The availability of 10 Gbps, 100 Gbps, and even faster networks makes it feasible to move large quantities of data over networks (i.e., as bits) rather than by shipping physical media (i.e., as atoms). Previous investigations have compared the efficiency of shipping data as atoms or bits from the perspectives of time and money, providing insights into when a budget-or time-sensitive user should prefer a communication or shipping network, or some combination of the two. Here we consider a different type of cost, namely energy. We develop energy cost models for transferring data via both bits and atoms and study costs in real-world settings. We find that it is often much more energy-efficient to transfer data as atoms rather than as bits. For example, in some cases ground shipping can consume up to 57× less energy than a network transfer. Moreover, compact data storage formats improve the energy efficiency of shipping by orders of magnitude. We also show that minimizing the overall energy cost when choosing between bits vs. atoms can be easily achieved using the classical min-flow problem. Our results suggest that as pressure grows to reduce the energy consumption of information technology, it may become attractive to integrate physical shipping more deeply into our communications infrastructure.