Recently, the internet of things (IoT) has gained popularity as an enabling technology for wireless connectivity of mobile and/or stationary devices providing useful services for the general public in a collaborative manner. Mobile ad-hoc networks (MANETs) are regarded as a legacy enabling technology for various IoT applications. Vehicular ad-hoc networks (VANETs) and flying ad-hoc networks (FANETs) are specific extensions of MANETs that are drivers of IoT applications. However, IoT is prone to diverse attacks, being branded as the weakest link in the networking chain requiring effective solutions for achieving an acceptable level of security. Blockchain (BC) technology has been identified as an efficient method to remedy IoT security concerns. Therefore, this chapter classifies the attacks targeting IoT, VANETs, and FANETs systems based on their vulnerabilities. This chapter explores a selection of blockchain-based solutions for securing IoT, VANETs, and FANETs and presents open research directions compiled out of the presented solutions as useful guidelines for the readers.
TopIntroduction
Nowadays, Internet of Things (IoT) (Stoyanova et al.2020) has experienced tremendous opportunities and potential interest from various applications allowing a seamless connection of multiple and diverse devices to the internet in order to exchange efficiently collected data.
With the growth of IoT applications, a rise of Mobile Ad Hoc Networks (MANETs) (Tripathy et al.2020), Vehicular Ad Hoc Networks (VANETs) (Hamdi et al.2020) and Flying Ad Hoc Networks (Mukherjee et al.2018) applications is recognized. MANETs is a network of mobile nodes that are connected wirelessly and characterized by a dynamic network topology. FANET is another class of ad-hoc networks that is a subcategory of VANETs which is a sub form of MANET as illustrated in figure 1.
Figure 1. MANET, VANET, FANET and IoT
At present, IoT systems are often dependent upon a centralized architecture where information is sent from the connected devices and equipment to a proprietary cloud where the data is processed using analytics and then sent back to those tiny IoT devices to coordinate them as with all centralized systems. All devices are identified, authenticated and connected through cloud servers and the data collected by the devices is stored in the cloud for further processing (Ali et al.2018).
This centralized network architecture cannot be able to respond to the growing needs of the huge IoT ecosystems with the growth of connected devices that will be approximately 75.44 billion, as announced in (Alam2018). This gathered data, stored in centralized servers, can be tampered and consequently lacks traceability. Furthermore, through the current architecture, users have limited control over their data and are made to trust the cloud and have no choice but to rely on their promises of security. Accordingly, IoT security efforts mostly focus on securing point-to-point communication and fall short in addressing security during the lifecycle of data by thinking about this problem of trust. IoT devices need to confidently exchange data without having to rely on an intermediary which adds friction and costs reconciliation problems and all sorts of transactional challenges.
In this context, Blockchain (BC) (Lu2019) is a tailored technology for such problems. It has attracted a tremendous interest from various IoT applications thanks to its distributed nature that implies no single entity controls the ledger, but rather the participating peers together validate the authenticity of records. These records are organized in blocks which are linked together using cryptographic hashes (Ferrag et al.2018). All the BC peers have to validate each record to get added to a block (Reyna et al.2018) in order to be uploaded to the BC. This agreement is achieved through consensus algorithms such as Proof of Work (PoW), Proof of Stake (PoS), Delegated Proof-of-Stake (DPoS), and Proof-of-Authority (PoA). Accordingly, BC keeps track through the data records and achieves a sort of distributed trust that can drastically reduce the cost of verification and bootstrap IoT platform without assigning a lot of market power or much control to one single entity.
Due to this distribution of computing power of resources or IoT devices with BC and its high traceability and trust level, the system designed with BC is much more resilient to attackers.
This technology is currently revolutionizing several IoT applications but still in its early stage of research with VANETs and FANETs.
Several surveys (Wang et al.2020) (Wang et al.2019b) (Fernández-Caramés and Fraga-Lamas2018) (Ferrag et al.2018) have been already proposed to present the IoT security challenges and to explain the integration of BC technology. However, to the best of our knowledge, there is no work on efficient handling of security vulnerabilities of various IoT, VANET and FANET applications by leveraging the benefits offered by BC technology, that has been discussed recently in the literature. In addition, there is no relevant work highlighting the taxonomy of security threats and their BC-based solutions. Hence, our chapter is presenting a synthesis of several BC-based solutions proposed for securing the IoT, VANET and FANET systems considering the inclusion of Edge, Fog and Cloud computing layers in their overall proposed architectures.