Evaluation and optimization of energy consumption in ad hoc networks

Motivation

Ad hoc networks are characterized by the ability to autoconfigure and establish links without the requirement of a central coordinating station. According to the decentralized nature, network management is done in a distributed way among the participating nodes. Especially, when the target device of the data is outside the range of coverage of the transmitting node. Ad hoc networks are especially attractive in scenarios where costs and complexity are a constraint to the deployment of telecommunications infrastructures.

Regarding their applications, beyond the initial conception focused on military applications or the support of communication to emergency events, today they represent a viable option for the implementation of new scenarios, such as the concept of opportunistic communication, motivated by the exponential growth of mobile computing [1]. In addition, the joint operation of specialized ad hoc networks (VANET’s, WSN, WMN, etc.) is a promising technological option for the design of Smart Cities-oriented services as well as for the implementation of applications based on Internet of Things [2. 3].

However, one of the main challenges to be faced is the limited autonomy of operation because nodes usually use batteries as a source of energy. In this sense, the optimization of consumption is paramount for practical purposes of application. In particular, the design of routing mechanisms considering energy constraints on devices represents an active field of investigation [4].

Overview

Devices with the greatest energy depletion in an ad hoc network are potential elements for link breakdown, increased packet loss as well as partial or total disconnection of the network. The task of the optimization mechanisms is to extend the life of the nodes through a balance in the expenditure. However, achieving a balance between the availability of the network and maintaining guarantees for the provision of services with quality levels required by users (QoE), is a task of great complexity.

With respect to the factors that contribute to the increase in energy demand in an ad hoc network, one aspect to consider is the popularity in the broadcast of multimedia contents, as well as the improvements obtained through recent wireless standards (IEEE 802.11n / ac). This causes a considerable increase of data traffic and, consequently, a greater consumption. On the other hand, the shared nature of the wireless medium and the operating principle of the radio interface are key factors in understanding the energy depletion at the nodes. In particular, the zones of interference are susceptible to an unnecessary increase of the operation in reception mode as well as to the greater number of attempts derived from the intense contest by the access to the channel. In particular, the overhead generated by envelope detection, generally called an overhearing effect, represents a considerable percentage of the energy demanded by the radio interface and is especially critical as the density of nodes in a scenario increases. In order to achieve greater equity in the consumption of energy resources, expenditure planning should be carried out considering not only the alternation of routes for the distribution of traffic flows, but also the interference conditions in the nodes that make a trajectory. Therefore, the analysis of the overhearing effect as well as the balance in the conformation of the routes, represent key aspects to optimize the energy consumption in an ad hoc network. In this sense, considering the current pragmatic approach in the field of ad hoc networks [4], the research group applies an experimental methodology based on simulation tools as well as testbed through development platforms (Single Board Computer) for the implementation and deployment of ad hoc nodes (Figure 1). The methodology adopted has allowed the study and development of optimization solutions of energy expenditure in real operating environments, as described in studies published by the research group available in [5] – [12].

Figure 1. Implementation and deployment in ad hoc networks

References

[1] M. C. and S. Giordano, “Mobile ad hoc networking: milestones, challenges, and new research directions,” IEEE Commun. Mag., vol. 52, no. 1, pp. 85–96, 2014.
[2] B. Rashid and M. H. Rehmani, “Applications of wireless sensor networks for urban areas: A survey,” J. Netw. Comput. Appl., vol. 60, pp. 192–219, 2016.
[3] T. Qiu, N. Chen, K. Li, D. Qiao, and Z. Fu, “Heterogeneous ad hoc networks: Architectures, advances and challenges,” Ad Hoc Networks, vol. 0, pp. 1–10, 2016.
[4] M. Fotino and F. De Rango, “Energy Issues and Energy aware Routing in Wireless Ad-hoc Networks,” in Mobile Ad-Hoc Networks: Protocol Design, Ed. InTech, pp. 281-293, 2011.

Related publications

[5] S. González, P. Arce, and J. C. Guerri, “Implementación de un banco de pruebas para redes inalámbricas ad hoc empleando plataformas Rasperry Pi y Node.js,” in Proc. of the Simposium Nacional de la Unión Científica Internacional de Radio (URSI), Madrid (Spain), Sep. 2016, article S3.2.2.
[6] S. González, T. R. Vargas, P. Arce, and J. C. Guerri, “Energy optimization for video monitoring system in agricultural areas using single board computer nodes and wireless ad hoc networks,” in Proc. of the Symposium on Signal Processing, Images and Artificial Vision (STSIVA), Bucaramanga (Colombia), Aug. 2016.
[7] S. González, P. Arce, and J. C. Guerri, “Simulation and testbed evaluation for optimizing energy consumption in ad hoc networks based on OLSR protocol,” in Proc. of the International Joint Conference on e-Business and Telecommunications (ICETE), Conference on Wireless Networks and Mobile Systems (WINSYS), Lisbon (Portugal), Jul. 2016, pp. 129-136.
[8] S. González, W. Castellanos, P. Guzmán, P. Arce, and J. C. Guerri, “Simulation and Experimental Testbed for adaptive video streaming in ad hoc networks,” in Ad Hoc networks,  available online, doi: 10.1016/j.adhoc.2016.07.007, 2016.
[9] S. González, P. Arce, and J. C. Guerri, “Técnica de buffering para la optimización del consumo de energía en la transmisión de tráfico multimedia en redes ad-hoc,” IEEE Latin America Transactions, vol. 13, no. 1, pp. 250-258, 2015.
[10] P. Arce, I. de Fez, F. Fraile, S. González, P. Guzmán, and J. C. Guerri “QoE en redes adhoc, descarga adaptativa de contenidos y vídeo 3D,” in Proc. of Jornadas de Ingeniería Telemática (JITEL), Palma de Mallorca (Spain), Oct. 2015, pp. 339-346.
[11] P. Arce, S. González, and J. C. Guerri, “Altruistic Networks: where every node matters,” Recent Advances in Ad Hoc Networks Research, Ed. Nova Science Publishers, pp. 41-68, 2014.
[12] S. González, P. Arce, and J. C. Guerri “Nodos estratégicos: una propuesta para mejorar la eficiencia energética en redes inalámbricas Ad-Hoc,” in Proc. of the Simposium Nacional de la Unión Científica Internacional de Radio (URSI), Valencia (Spain), Sep. 2014, article no. 203.