Is your phone draining its battery too quickly? The problem may depend on the different protocols we use to surf the web, and the latest ones are not necessarily the most energy-efficient. This is the conclusion of a study conducted by the University of Pisa and the CNR Institute for Informatics and Telematics, recently published in the journal Pervasive and Mobile Computing.
Specifically, the researchers set out to evaluate the energy consumption of smartphones and Internet of Things (IoT) devices in relation to the various HTTP protocols that underpin data transmission over the Internet.
“In general, when we talk about the different versions of the HTTP protocol, the focus is on ‘performance’, which is the time required to download data and resources over the network,” explains Alessio Vecchio, author of the study and professor at the Department of Information Engineering at the University of Pisa. “Our study, on the other hand, focused on energy consumption, which is particularly relevant in the context of the Internet of Things (IoT), where many devices are battery-powered. In this context, saving energy makes it possible to significantly extend the life of the device, avoiding the need to replace or recharge batteries, with positive consequences in terms of sustainability and usability.”
A photo of the system
The HTTP protocol is one of the most widely used communication protocols in computer networks; suffice it to say that the web is based on it. Communication between IoT devices, such as sensors or home automation systems, is also often based on the HTTP protocol. Currently, the three main versions are HTTP/1.1, HTTP/2 and the newer HTTP/3, which differ significantly in terms of performance. The study found that HTTP/3, which is generally more efficient than the previous versions, can consume up to 30% more in some scenarios. This happens, for example, when there is a lot of data to transfer, while it consumes less than the others when the volume of data is smaller.
“Our study is important for two reasons, one practical and one scientific,” Vecchio points out. ‘From a practical point of view, thanks to the results obtained, those who are interested in building systems that use smartphones and IoT devices can make choices that take into account energy aspects. From a scientific point of view, new research scenarios are opening up, such as the study of intelligent algorithms capable of dynamically selecting the most energy-efficient version of the HTTP protocol depending on the communication scheme, the amount of data to be transferred and the network conditions.”
The research was carried out in the context of the Future-Oriented REsearch LABoratory (FoReLab), a project of the Department of Information Engineering of the University of Pisa, funded by the Ministry of University and Research (MUR) within the framework of the Departments of Excellence programme.
Besides Alessio Vecchio, the study was conducted by Chiara Caiazza, PhD student in Smart Computing (joint PhD programme of the Universities of Florence, Pisa and Siena) and Valerio Luconi, PhD student in Information Engineering at the University of Pisa in 2016 and researcher at the CNR Institute of Informatics and Telematics since 2019.
All three participants in the research group share an interest and concern for environmental issues, in particular energy sustainability. Therefore, the study of the energy implications of network protocols was an excellent start to combine research aspects related to computer science and systems engineering with energy saving issues.