Adaptive role switching for fair and efficient battery usage in device-to-device communication

Abstract

By leveraging device-to-device communication, opportunistic networks promise to complement infrastructure-based networks, by enabling communication in remote areas or during disaster and emergency situations, as well as by giving rise to novel applications, such as location-based sharing. Yet, to become feasible in practice and accepted by users, it is crucial that opportunistic communication be energy-efficient. Through extensive and detailed measurements and analysis, we show in this paper, that all of today's device-to-device communication technologies suffer from two grave energy consumption problems: very expensive neighbor discovery and unfair connection maintenance. We consider the two most well-known technologies -- Wi-Fi Direct and Bluetooth, and a third solution based on the WLAN access point mode -- WLAN-Opp. We carefully design a measurement setup which allows us to isolate the energy consumption of individual operations (e.g. CPU sleeping/waking up, scanning/listening for neighbors etc) for thesetechnologies and compare the technologies based on these measurements. Our analysis reveals that neighbor discovery can quickly drain a device's battery, depending on the required scanning frequency. In addition, once a connection is established, the "host" of the connection consumes two to five times the energy needed by a "client". To solve this unfairness problem, we propose a strategy that periodically alternates the hosting role among the peers. Further, we minimize the cost of the role switching operation by using the distribution of the residual connection time of two peers to calculate an adaptive switching period. We examine the trade-off between fairness and switching cost on real-world connection traces and show that our scheme largely outperforms static role switching. Finally, we demonstrate that our fair role switching scheme is also effective when run on real devices.

A Decade of Research in Opportunistic Networks: Challenges, Relevance, and Future Directions

“…To discover communication opportunities without the aid of an infrastructure, the mobile devices need to continuously advertise their presence in the network. With the available technologies, this operation is too power-hungry for the limited battery capacity of modern smartphones [5].…”

DiscoverFriends: secure social network communication in mobile ad hoc networks

“…In its reduced form, DiscoverFriends' model can be simplified as target nodes do not serve as intermediary nodes for other target nodes as shown in Figure 2. However, during prolonged application usage, it may be energy efficient [14,15] to pass group ownership to a target node (i.e., x1) once the secure environment has been set up. This sets the need for an efficient key management scheme specifically designed for MANETs.…”

Energy Modelling and Fairness for Efficient Mobile Communication

“…While Bluetooth is not the main technology used in the thesis, we provide few references to interesting studies [67,84,155,183,242]. These can be used to add Bluetooth models to EnergyBox.…”

“…Mobile device clusters are often formed using WiFi software access points (SoftAP) or other technologies such as Bluetooth, and thus comparing the energy footprint of the different technologies used for D2D is important [155,242]. Improving the energy efficiency of the device that creates the SoftAPs has been studied by researchers [41,94,117,228].…”