Blockchain in IoT and Beyond: Case Studies …
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Survey on Blockchain in IoT and IIoT
Blockchain is now intensively used for IoT and IIoT. Section 2.1 gives an introduction
to IoT and IIoT followed by Sect. 2.2, which gives the survey of blockchain on recent
work and also proof of concepts of Distributed Ledger Technology (DLT) [13].
2.1
IoT and Industrial IoT
The Internet of Things (IoT) is the interconnection of devices and systems used
to connect and communicate over the Internet. Sensors, devices, connectivity, data
processing, and the user interface make the IoT the technology for the future.
Industrial IoT(IIoT) [14] is a subset of IoT. IIoT as the name suggests is generally
used for the industrial sectors and applications. The use of artificial intelligence,
machine learning, big data analytics, distributed system, cyber-physical systems has
made the IIoT technologies [15], a boon with a reduction in human error and labor,
an increase in efficiency, and a reduction of costs.
However, the possibility of cyber-attacks [16] and breach of security and privacy
[17] is common in IoT [18]. This is more devastating in the case of IIoT. There
are challenges in interoperability, [19] privacy, and security. The use of blockchain
technologies may be the solution to overcome this problem in IoT and IIoT.
Figure 1 gives an architectural diagram, and in broad sense, IoT has four-layered
architecture as below:
Sensing Layer: The IoT is basically useful for this layer. This layer consists of
hardware components, which collects real-time data from the environment. These
have hardware like camera, various types of sensors (temperature, motions etc.),
GPS, microphone, and many more.
Network Layer: The data collected by sensors must be transferred to computing
devices. This layer basically uses the existing network to transfer these data.
Data Processing Layer: These are the computers that receive the data and process
it to generate information.
Application Layer: This layer uses the information generated by data processing
layer and represents it to user, for example traffic conditions of a route.
Figure 2 gives the basic architecture of IIOT. IIoT basically consists of IoT, Cloud,
and Edge computing facility for industrial requirements. IIoT consists of data sources
as collected by sensors then these data are processed in edge layer, the next layer
of IIoT. As industry requires a huge collection of data so cloud gateway comes in
the next layer, and finally, execution and integration are being done in industry or
factory using IIoT.