Protocols and Communication

Bryan Kibet
7 min readDec 1, 2022

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A gentle introduction to the Internet of Things (IoT)

TL; DR? How Does IoT Work?

First, it acquires information with respect to basic resources (addresses and names) and related attributes through sensors, RFID tags and all other uniquely identifiable objects, “things” using a central hub like a mobile phone.

It then integrates the object related information into the communication network and then intelligently indexes the information gathered by the many objects.

Finally, utilizing a combination of technologies such as semantic analysis, data mining and cloud computing, it analyses and processes the information from the objects to realize an intelligent decision and control in the physical world.

How Does IoT Work?

A really gentle introduction?

Internet of Things (IoT) is a connection of physical devices, “things”, over the internet such that they can communicate with each other and perform tasks autonomously (that’s where the name smart devices came from). To enable such capabilities, the devices are equipped with embedded sensors, processors, transceivers and actuators. The power of IoT lies in its large size of device connections. As of 2021, about 12.2 billion devices were actively connected around the globe and this is projected to reach 14.4 billion by year end 2022.

Well, if my hand dryer senses my hand and turns on, is that IoT? Obviously, it is not. Yes, it has sensors and actuators, but beyond that, it is not really connected to anything else. The power of IoT lies in its connectivity (the internet and other protocols, but mostly using the internet protocol).

… if my hand dryer senses my hand and turns on, is that IoT?

Figure 1: A real life application of IoT

Internet of Things (IoT) is a connection of physical devices, “things”, over the internet such that they can communicate with each other and perform tasks autonomously

The most commonly used networking technologies in IoT are cellular, Wi-Fi, Ethernet, Low Power WAN (LPWAN), Radio Frequency Identification (RFID), Near Field Communication (NFC), Bluetooth Low Energy (BLE), Narrow Band-IoT (NB-IoT), Sigfox, ZigBee, Wi-Fi and Long-range Radio Wide Area Network (LoRaWAN). These connectivity options have varying range and speed to suit different deployment needs.

No truth is more apt to IoT than: IoT cannot exist in a void. A lone sensor is useless. A bunch of them is good, but they have to be connected to one another and to platforms generating data for further use. This wide network of connected devices and technologies applied toward a specific goal is an IoT ecosystem. The four basic elements of an IoT ecosystem are sensors (the “things” of the system. They collect data from its surroundings) processors, gateways (such as LAN and WAN.They route the processed data and send it to proper location) and applications (such as home automation apps, security systems). In the simplest of terms, a device in the ecosystem collects data and then sends it across the network to a platform. The platform then aggregates the data and makes it available for use.

No truth is more apt to IoT than: IoT cannot exist in a void. A lone sensor is useless. A bunch of them is good, but they have to be connected to one another and to platforms generating data for further use.

Figure 2: The four basic elements of an IoT ecosystem are sensors, processors, gateways and applications

Communication Protocols used in IoT

A communication protocol is a set of rules governing how data is exchanged securely among devices, processing units or data centres. Without these protocols, hardware would be useless. It is important to note that there is no one-size-fits-all IoT protocol. The protocols used depend mostly on the industry and the specific application. The protocols are decided based on cost, data transmission rate, bandwidth, security, intermittent connectivity, power consumption and range. For a particular application, for instance smart agriculture, the wireless communication protocols are optimised for efficient data transmission between components depending on the application of the system.

Figure 3: IoT Smart home platform

Without these protocols, hardware would be useless

Against the wider IoT protocols landscape, the communication protocols (transport, connectivity, link and session) form the base of the landscape. Above them are the data processing, storage (such as Mongo DB) and application layers (such as machine vision and asset management) as illustrated in figure 4. These various parts have to be configured correctly and in their compatibility with the standard hardware verified so as to ensure a functional and efficient connectivity.

Figure 4: IoT protocols landscape from device to applications. The list is non-exhaustive and some technologies overlap over some protocols.

Another perspective of viewing Figure 4 is that IoT technology consists of three stacks: IoT devices, IoT protocols and connectivity and IoT platforms. IoT devices include actuators (effect a change in the environment such as the temperature controller of an air conditioner), embedded systems (manage specific functions within a larger system using on board microprocessor or microcontroller), Intelligent devices (have compute ability), sensors (detect changes in the environment), transducers, Microcontroller Units (MCUs) and Microprocessor Units (MPUs).

IoT technology consists of three stacks: IoT devices, IoT protocols and connectivity and IoT platforms.

Figure 5: From device to Network. Gateways facilitate the indispensable device-to-device and device-to-network connection

The IoT protocols and connectivity stack deals with the way devices connect and communicate with each other. The communication can be through gateways or built-in functionality. IoT gateways are usually used for device-to-device communication or connection to the network for devices that are not IP based. Connection of devices to the IoT network is categorized as long-range and short-range depending on their capabilities for transmission over some distance. The low-power short-range protocols such as ZigBee, Bluetooth, NFC and Wi-Fi are capable of short-range transmission. The key low-power, wide-area networks (LPWAN) are LoRaWAN, Sigfox, NB-IoT and 5G IoT. Table 1 gives a comprehensive presentation of the key features of the connectivity protocols used in wireless communication in IoT.

Table 1: A comparison of the key wireless communication technologies used in IoT applications — standard, bandwidth, latency and topology

Networks are built as a “stack” of technologies. Bluetooth LE technology for instance is at the bottom of the stack. A technology such as IPv6 (used for network traffic routing and logical device addressing) is further up the stack because it is used by applications running on top of such layers. From this basic principle arises the various architectures for implementing communication protocols in IoT. The simplest one is the three layer architecture comprising of the Perception layer, Network layer and Application layer.

Networks are built as a “stack” of technologies. Bluetooth LE technology for instance is at the bottom of the stack. A technology such as IPv6 (used for network traffic routing and logical device addressing) is further up the stack because it is used by applications running on top of such layers. From this basic principle arises various architectures for implementing communication protocols in IoT.

Figure 6: The three layer architecture comprising of the Perception layer, Network layer and Application layer.

This architecture is however considered too simplistic for some use cases. The four layer Transmission Control Protocol/Internet Protocol (TCP/IP) network architecture is the one that is most commonly used for implementing communication protocols in IoT. It is a modification of the seven protocol layer Open Systems Interconnection (OSI. The result of the OSI model modification is that we get Network Access and physical layer, Internet layer, Transport layer and application layer as in figure 4.

Figure 7: The general OSI model, the TCP/IP model and IoT network technology used in the TCP/IP model layers. The list is non-exhaustive.

The IoT platform stack generally occupies the top most layer of the IoT protocol landscape. They are the binders of the IoT ecosystem. IoT platforms simplify the building, deploying, launching, managing and monitoring of IoT projects. They act like administrators and provide a single service that manages the devices, data and deployment. They take care of the device life cycle. Choosing the right IoT platform is very important. The right IoT device management platform should be scalable, versatile, secure and adaptable.

Figure 8: IoT platforms simplify the building, deploying, launching, managing and monitoring of IoT projects

Through the platform stack, the user/developer can operate and maintain their IoT ecosystem. IoT platforms support integration with almost any connected device and blend in with third-party applications used by the device. This allows a single IoT platform to manage any kind of connected device. IoT platforms also provide components for frontend and analytics, on-device data processing, and cloud-based deployment and can also handle end-to-end IoT solution implementation from the ground up. Some examples of IoT platforms are ThingWorx, Google Cloud Platform, IBM Watson IoT, Microsoft Azure IoT Suite, and AWS IoT core.

Figure 9: Google Cloud Platform

Instead of a conclusion

We come back full circle. How Does IoT really Work?

First, it acquires information with respect to basic resources (addresses and names) and related attributes through sensors, RFID tags and all other uniquely identifiable objects, “things” using a central hub like a mobile phone.

It then integrates the object related information into the communication network and then intelligently indexes the information gathered by the many objects.

Finally, utilizing a combination of technologies such as semantic analysis, data mining and cloud computing, it analyses and processes the information from the objects to realize an intelligent decision and control in the physical world.

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