BCoT: Introduction to Blockchain-Based Internet …

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Fig. 5 Illustration of IoT layered architecture

Sensing and perception layer: This layer comprises many IoT devices, including

sensors, actuators, controllers, RFID tags, smart meters, and wearable devices. The

variety of devices deployed for data acquisitions are collectively called edge devices.

These edge devices interface with the environment to collect data. Some specific

nodes, equipped with actuators and controllers, classify the data, make decisions,

and perform suitable actions according to the environment.

Communication Sub-layer: IoT gateways, Wi-Fi access points, and Base

Stations (BS) build up the communication sub-layer of the IoT architecture. The edge

devices connect with the nodes in the communication sub-layer by diverse commu-

nication protocols like Bluetooth, Near-Field Communication (NFC), Low-power

Wireless Personal Area Networks (6LoWPAN), Wireless Highway Addressable

Remote Transducer (Wireless HART) [51], and Low-Power Wide Area Networks

(LoPWAN) technologies including Sigfox, LoRa, narrowband IoT (NB-IoT), and

industrial Ethernet [52]. Different devices are equipped with varying communication

technologies, producing a heterogeneous wireless network demanding specialized