Citation: López Delgado, J.L.;
Álvarez Bermejo, J.A.; López
Ramos, J.A. Homomorphic
Asymmetric Encryption Applied to
the Analysis IoT Communications.
Sensors 2022, 22, 8022. https://
doi.org/10.3390/s22208022
Academic Editors: Daniele Giusto
and Matteo Anedda
Received: 17 September 2022
Accepted: 17 October 2022
Published: 20 October 2022
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Article
Homomorphic Asymmetric Encryption Applied to the Analysis
of IoT Communications
Juan Luis López Delgado
1,†
, José Antonio Álvarez Bermejo
1,†
and Juan Antonio López Ramos
2,
*
,†
1
Department of Informatics, University of Almeria, 04120 Almeria, Spain
2
Department of Mathematics, University of Almeria, 04120 Almeria, Spain
* Correspondence: jlopez@ual.es
† These authors contributed equally to this work.
Abstract:
In this paper, we describe the use of homomorphic encryption techniques in order to not
only ensure the data are transmitted in a confidential way, but also to use the encrypted data to
provide the manager with statistics that allow them to detect the incorrect functioning of a sensor
node or a group of sensors due to either malicious data injection, data transmission, or simply sensor
damage (miscalibration, faulty sensor functioning). Obtaining these statistical values does not need
decryption, so the process is sped up and can be developed in real time. Operating the data in this
way ensures privacy and removes the need to maintain a shared key infrastructure between the
sensor nodes and the manager nodes that are part of the blockchain infrastructure. In this work, we
focus on operations with the sensor nodes that provide data that will be, later, treated as part of the
business logic in the agribusiness sector (for example), hence the importance of having fast checking
mechanisms in terms of data quality. The results obtained on conventional configurations of sensor
nodes encourage the use of this technique in the aforementioned infrastructure.
Keywords: asymmetric encryption; homomorphic encryption; IoT
1. Introduction
Wireless sensor networks constitute an integral part of most Internet of Things (IoT)
devices, and their presence nowadays in our lives is growing exponentially [
1
]. The
application areas of this emerging technology go from the development of autonomous cars
to e-health, defense, or smart cities [
2
]. The transmitted data through the wireless sensor
network is transformed into information, which is used to make decisions. Therefore,
in most cases, a key point is to ensure the security of communications, and this leads to
focusing on security requirements [
3
], which include confidentiality, integrity of the data
transmitted, authentication of the source, and non-repudiation. Achieving these objectives
is of crucial importance [
4
], especially in an environment where no human interaction is
present, as is proposed in the definition of the IoT [
5
] as an interrelated system of devices
with the ability to transfer data over networks. In this way, providing security for IoT
communications presents different challenges The first one is to to find a way to maintain
security with a technology requiring very limited computing resources, data storage, and
even power consumption. The use of lightweight cryptographic algorithms helps to achieve
the security requirements as well as energy savings. A second point to consider is data
processing. It could be that our IoT application interconnects a large number of IoT devices
which generate a huge quantity of data that aim to make decisions in real time; thus, it is
necessary that the architecture uses scales with a wide range of sensors and, at the same
time, provides interoperability since the network could be heterogeneous, where some
devices simply transmit data, whereas there exist others that could perform computations
that help in decision making.
In [
6
], the authors introduce a solution based on blockchain technology that takes into
account all the preceding requirements. The use of blockchain in IoT networks is not new
Sensors 2022, 22, 8022. https://doi.org/10.3390/s22208022 https://www.mdpi.com/journal/sensors
