User-in-the-loop: spatial and temporal demand shaping for sustainable wireless networks

The demand for wireless access data rates is growing exponentially at a pace where supply cannot keep up with. Wireless resources (spectrum, time, space) are limited and shared, and transmission rates cannot be improved anymore solely with physical layer innovations. On the consumer side, flat rate type tariffs have established unnecessarily high expectations and often wasteful consumption. Dealing with congestion is unavoidable as a consequence of operating in a regime where demand is close to, equal to, or exceeding the supply. We can no longer assume that the current over-provisioning approach continues to be feasible. Complementary to the engineering for the growth of the supply side, this article focuses on the engineering for the control of the demand side. An approach referred to as the “user-in-the-loop” (UIL) is therefore motivated here. This article proposes spatial control, in which the user is encouraged to move to a less congested location, and temporal control, in which incentives (e.g., dynamic pricing) ensure that the user reduces (or postpones) his current data demand in case the network is congested. Results from a survey, which measures how willing a user is to respond to such control, are also presented. As users are modeled by a system-theoretic box in a closed-loop (control) system, they feature an input handle for incentives and an output handle for the reaction. Incentives can be progressive tariffs, reward programs, higher access rates, or even environmental (green) indicators. Incentives are tailored to the major Quality-of-Service (QoS) classes and help to shape the demand at the application layer-7 as well as at the user (“layer-8”). UIL can safely be applied in addition to other technologies, which are mainly for increasing the supplied capacity.