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Internet of Things (IoT): Concepts, Issues, Challenges and Perspectives

This chapter is an in-depth review of our article published in 2017. We considered some elements to develop concepts based on the IoT. In this chapter, we present: (1) the connected object (CO), (2) a definition of the Internet of Things, (3) steps and technologies in the IoT ecosystem, (4) IoT to the Internet of Everything (IoE), (5) IoT and Big Data, (6) cloud computing applied to Big Data and the IoT, (7) data science and the IoT, (8) issues and challenges of the IoT, (9) opportunities and threats in the IoT ecosystem, (10) security of the IoT, (11) blockchain and the IoT and (12) conclusion, summarizing the perspectives of the IoT.

1.1. Introduction

The Internet in general and the Web in particular have continued to evolve - from the Web of information to the Web of individualized1 Things - via various connected objects thanks to miniaturization and technological development, which make room for a double approach: being connected and communicating consistently without any constraints as regards space and time so as to meet the demands and needs of users in terms of services, communication and information [ROX 17, THE 13].

The Internet is gradually transforming into a HyperNetwork, just like a network consisting of multitudes of connections between artifacts (physical, documentary), actors (biological, algorithmic), scripts and concepts (linked data, metadata, ontologies, folksonomy), called the "Internet of Things (IoT)", connecting billions of people and objects. It has become the most powerful tool ever invented by man to create, modify and share information. This transformation shows the evolution of the Internet: from a computer network to a network of personal computers, then to a nomadic network integrating communication technologies [CHA 12]. Developments in machine-to-machine (M2M) technologies for remote machine control and the first use of IP (Internet Protocol) in the year 2000 on mobile cellular networks have accelerated the evolution from M2M to the IoT [WOO 11].

1.2. The connected object (CO)

Before defining IoT concepts, it is important to define a connected object as being a device whose primary purpose is neither to be a computer system nor to be a Web Access interface. For example, an object such as a coffee machine or a lock was designed without integrating a computer system or Internet connection. Integrating an Internet connection to a CO enriches it in terms of functionality and interaction with its environment. This makes it an Enriched CO (ECO); for example, the integration of an Internet connection to a coffee machine will make it remotely accessible.

A CO can independently interact with the physical world without human intervention. It has several constraints such as memory, bandwidth or energy usage. It must be adapted for a purpose and has some form of intelligence, which is the ability to receive and transmit data with software through embedded sensors [ROX 17]. A CO has value when connected to other objects and software components; for example, a connected watch is only relevant within a health or wellbeing-oriented ecosystem, which goes far beyond knowing the time.

A connected object (CO) has three key elements:

• - generated or received, stored or transmitted data;
• - algorithms to process this data;
• - the ecosystem in which it will react and integrate.

Use properties of a CO [SAL 17] are:

• - ergonomics (usability, workability, etc.);
• - aestheticism (shapes, colors, sounds, sensations, etc.);
• - usage (cultural history, profile, social matrix, etc.);
• - metamorphism (adaptability, customization, modulation, etc.).

Some researchers talk of "hyper objects" [MAV 03] as able to pool their resources to perform everyday tasks as they are linked by "invisible links" within the same ecosystem. In this context, researchers such as [WEI 93] have already considered ubiquitous computing to be where "the most profound technologies are the ones that have become invisible. Those ones which, when tied together, form the fabric of our daily life to the point of becoming inseparable" [WEI 91, p. 94].

Communication between objects is passed through identifications that are known to each other. An object must have one or more IDs (barcodes) to be recognized by another so as to establish connection. The GS1 system has proposed a technology based on RFID tags2 that will uniquely associate the logistical information related to an object with a URL. Google has proposed the Physical Web project to uniquely associate a URL with an object3. The ubiquity of heterogeneous, mobile and fragile objects in our life poses the problem of trust models adapted to this complex and fragile ecosystem [SZO 17]. Behind these technologies is the fight for norms and standards for the IoT between giant Internet companies because each wishes to impose its technologies.

1.3. Internet of Things: definition

Kevin Ahston4, the co-founder of MIT's Auto-ID Center, used the term "Internet Of Things" in 1999. The term IoT was first used during a presentation made by Procter & Gamble (P&G). This term conjures up the world of objects, devices and sensors that are interconnected5 through the Internet.

The CERP-IoT (Cluster of European Research Projects on the Internet of Things) defines the Internet of Things as: "a dynamic infrastructure of a global network. This global network has auto-configuration capabilities based on standards and interoperable communication protocols. In this network, physical and virtual objects have identities, physical attributes, virtual personalities, intelligent interfaces, and are integrated into the network in a transparent way" [SUN 10].

This definition presents the two sides of the IoT: the temporal and spatial sides, which allow people to connect from anywhere at any time through connected objects [CHA 12] (Figure 1.1) (smartphones, tablets, sensors, CCTV cameras, etc.). The Internet of Things must be designed for easy use and secure manipulation to avoid potential threats and risks, while masking the underlying technological complexity.

Figure 1.1. A new dimension for the IoT

(source: ITU 2005 [INT 05, taken from [CHA 12])

The rapid evolution of this "Internet of Things" shifts the balance between computer and everyday products due to two factors: the generalization of computing resources and the ownership of Web services by users [THE 13].

1.3.1. Applications

IoT applications are now practically affecting our day-to-day life such as:

• - health and telemonitoring systems to help people;
• - connected agriculture to optimize the use of water;
• - connected vehicles to help optimize urban traffic management;
• - connected appliances to help optimize the consumption and distribution of electrical energy;
• - digital arts;
• - connected watches for wellbeing and sport.

These examples of applications show that the IoT is integrated into our daily lives and improves people's quality of life [BOU 17a, BOU 17b, NOY 17, AMR 17, GAG 17, CRO 17]. It gives rise to a new market by creating new jobs and trades. It also helps businesses grow, and gives impetus to competitiveness. According to the GSMA [GSM 18], the IoT is a huge growing industry at all hardware and software levels that is expected to provide mobile operators with a comfortable income of about $1200 billion by 2020.

1.4. Steps and technologies in the IoT ecosystem

COs are at the heart of the IoT, but it is necessary to connect all of these objects and enable them to exchange information and interact within the same network. The setting up of the IoT goes through the following steps: identification, sensors setup, object interconnection, integration and network connection. Table 1.1 presents possible steps and protocols [ROX 17].

Table 1.1. Steps and technologies to set up the IoT [ROX 17, p. 73]

1.4.1. IoT architecture

Given the rapid development of the IoT, it became necessary to have a reference architecture that would standardize systems design and promote interoperability6 and communication between the different IoT ecosystems...