All Must-Know IoT Protocols Shaping the Way We Connect

Connecting over 15 billion devices, the Internet of Things (IoT) redefines how we live and work. Yet, the path to seamless connectivity is far from a straight line. Why? The large selection of IoT protocols is one of the main reasons.

Not all Internet of Things protocols suit every deployment or device. That’s why when working on a smart home automation system, industrial automation solutions, or wearable gadgets, you’ll soon realize that choosing the perfect fit is no simple task. Power, security, and compatibility are just a few requirements to consider.

But don’t worry. WebbyLab is here to help. We’ll go through all popular protocols in IoT so you can select one for your unique needs. Drawing on our experience with 2Smart Standalone, 2Smart Cloud, and other Internet of Things projects, we’ll cover connectivity matters in the greatest detail.

 2Smart Cloud platform built by WebbyLab

Types of IoT Protocols

Communication protocols are a set of rules that handle communication between devices. There are many of those, and here’s why.

IoT systems are usually complex solutions that use several protocols at once. For example, here’s a combination you could use for medical IoT:

• BLE to connect wearable health monitors to a patient’s smartphone
• MQTT to transmit real-time patient data to healthcare providers
• HL7 to exchange healthcare data across various systems and devices

These protocols are the different layers of an IoT ecosystem. Now, let’s discuss the Open Systems Interconnection (OSI) model — a valuable framework for understanding those layers.

The OSI model consists of seven layers, following a top-down approach. The layers gradually descend from average user interactions to fundamental components like Ethernet cables. They include the following:

1. The application layer — enables access and management of IoT systems through mobile and web applications
2. The presentation layer — encrypts and transforms IoT data in a readable format at the application layer
3. The session layer — defines when and how devices communicate
4. The transport layer — ensures efficient data transmission
5. The network layer — coordinates data routing, determining where and how it transfers within the system
6. The data link layer — corrects errors and establishes between various devices
7. The physical layer — consists of tangible elements like Ethernet cables and cell towers

The OSI model is just a concept. Though this seven-layer structure works well for IoT, it poses several challenges. In particular, it often appears too complex for IoT devices with limited capabilities and computing powers. 

Luckily, there’s a more IoT-centric and simplified approach, which comprises the following four layers:

1. The application layer in IoT — allows for user interaction with IoT systems and communication session scheduling
2. The transport layer — ensures reliable end-to-end data transfer between IoT devices
3. The network layer — coordinates the packages of data within the IoT network
4. The physical and media access control (MAC) layer — deals with the physical infrastructure of IoT

The OSI model vs. the IoT-centric model.

Top 9  Most Used IoT Protocols

We briefly mentioned the various protocols used in IoT. Now, it’s time to explore the most commonly used iot protocols in greater detail.

IoT Messaging Protocols

• MQTT (Message Queuing Telemetry Transport). It belongs to the lightweight IoT messaging protocols. MQTT uses a publish-subscribe messaging approach and works best in low-bandwidth, high-latency, and unreliable networks. It suits real-time data exchange in IoT applications – a go-to choice for devices with limited processing power.
• AMQP (Advanced Message Queuing Protocol). AMQP is a versatile open-source messaging protocol. Its primary purpose is to facilitate communication within message-oriented middleware (MOM). What sets AMQP apart is its ability to connect various systems, devices, and applications — all without being bound to specific message brokers or platforms. Thus, AMQP is an excellent choice for IoT environments seeking secure and efficient message queuing and routing.
• CoAP (Constrained Application Protocol). This protocol is best for resource-constrained networks. It facilitates data transfer with low overhead, being perfect for applications where power efficiency is critical.
• XMPP (Extensible Messaging and Presence Protocol). Initially developed for instant messaging, XMPP has found its place in IoT. It allows for real-time device communication in scalable systems.

Web-Based IoT Communication Protocols

• HTTP (Hypertext Transfer Protocol). While not exclusive to IoT, HTTP is crucial for web-based IoT applications and is probably the most well-known iot protocol. It bridges IoT devices and web servers, helping with data management through web interfaces. However, this protocol has several drawbacks, like significant power consumption and weight concerns.
• WebSocket. It’s a bidirectional communication protocol that connects IoT devices and servers. Thanks to WebSocket, devices send and receive information simultaneously. It’s best for use cases when real-time communication is necessary. This protocol is also suitable in low-latency environments.

Wireless IoT Protocols

• Bluetooth and BLE (Bluetooth Low Energy). Bluetooth technology and its low-energy variant, BLE, are widely adopted in IoT. In particular, they connect smartphones, tablets, wearables, and smart home devices. Both techs are energy-efficient and easy to implement.
• Zigbee. It’s a mesh network protocol for low-power, short-range (up to 200 meters) connections. It’s common in home automation and industrial environments.

Home and Building Automation Protocol

• KNX (Konnex). This protocol is among the IoT standards for home and building automation. It integrates and manages devices and systems like lighting, IoT solution for HVAC, and security.

Applications of IoT Protocols in Different Industries

IoT protocols resemble versatile tools in a craftsman’s workshop, each suitable for specific tasks. Therefore, some protocols work better than others, depending on the industry and application. Here’s how internet of things protocols empower various niches:

• MQTT — for fast and reliable communication in healthcare
• AMQP — for secure message queuing in healthcare applications
• Zigbee — for connecting smart home devices like lights or thermostats
• Bluetooth/BLE — for linking personal devices like smartphones and wearables
• HTTP — for remote monitoring of industrial equipment, smart home appliances, and other devices through web interfaces
• Modbus — industrial IoT protocols for supervising equipment and collecting data
• CoAP — for low-power communication in various industries like healthcare, industrial automation, and environmental monitoring
• LoRaWAN — for remote monitoring of crops and livestock in agriculture

Trends and Future of IoT Protocols

The Internet of Things is currently a $662 billion market. It’s expanding rapidly, accelerating IoT protocol adoption and usage. Here are the most significant trends to look up to:

• Increased connectivity. IoT devices are expected to almost double from 2020 to 2030, surpassing 29 billion gadgets.
• Enhanced security. The growing number of connected devices raises data safety concerns. That’s why the security market in IoT technology will grow by 28% annually from 2023 to 2028, reaching $59 billion.
• AI integration. Future protocols can leverage Artificial Intelligence (AI) technology, improving data collection and processing. The global market of AI in IoT has reached about $82 billion in value.

WebbyLab Experience in IoT Protocols

WebbyLab experts leverage two approaches to establishing IoT communication. Let’s go through each of them.

The first scenario involves communication through a gateway. Here, the gateway is an intermediary. It communicates with devices and sensors and then transmits the gathered information to the cloud. Conversely, it receives commands from the cloud and sends them to the necessary end devices.

In the second scenario, devices connect to the network independently and directly communicate with cloud-based software (like 2Smart Cloud) or standalone platforms (like 2Smart Standalone).

The different types of IoT protocols and the way they communicate.

It’s a complex process that comprises several stages:

1. Initially, communication occurs between the sensor (or the controlled module) and the module so it can communicate with the cloud.
2. The second stage encompasses communication between the module and the cloud itself.

In both scenarios described above, these modules are essential.

1. In the first scenario, the gateway is the intermediary module for cloud communication.
2. In the second scenario, it’s a module embedded within the device.

This intermediary or gate module communicates with end nodes, implementing the full OSI model with all its layers. It requires built-in software within the gate or module to receive, process, and protect information.

Generally, both architectures (or scenarios) can handle the following three tasks:

Task 1: Data Reception from Sensors and Device Control

It doesn’t matter whether you deal with a gateway-based architecture or another setup. At the physical level, the hardware components responsible for collecting telemetry or controlling devices aren’t smart on their own. An IoT device is a complex solution that incorporates various technologies.

Consider a typical temperature sensor, for instance. It measures temperature and provides this data upon request or autonomously initiates data transmission. Similarly, a relay can respond to received commands, or the sensor can make decisions based on its firmware.

A physical connection is crucial to ensure these operations function seamlessly. It links the module receiving telemetry from the sensor or command between the cloud and the end device or sensor itself. This connection can take the form of wired or wireless technologies.

Popular wired technologies include the following:

• RS-485/232
• Twisted pair
• Ethernet
• CAN-bus
• USB
• I2C
• SPI
• HDMI
• PLI

Meanwhile, here are the most common wireless technologies:

• Wi-Fi
• Bluetooth
• Zigbee
• Z-Wave
• LoRaWan
• NFC
• RFID

With the help of these technologies, data from the end node travels to a module that delivers it to the cloud.

Task 2: Internet Connectivity

Both architectural versions share the ability to communicate with devices from the cloud via network connectivity technologies. These technologies are Wi-Fi, Ethernet, 2G-5G, and more.

First and foremost, every IoT solution hinges on an Internet connection. This connection can take one of two routes:

• Direct connectivity. A specific device, say through Wi-Fi, connects to the network. It establishes a link to an MQTT broker or a REST API hosted on a cloud server.
• Gateway connectivity. A gateway communicates with the cloud and the end devices using different IoT protocols (Zigbee, Z-Wave, LoRa, RS-232, or RS-485). It’s a viable communication option since not all devices can communicate with the cloud over the Internet. And that’s where the gateway steps in.

In essence, an IoT solution will have an end device equipped with a network-access module. For multi-device scenarios, it’s a gateway that handles network connectivity.

Task 3: Data Transfer to the Cloud

Once the gateway establishes an online connection and collects data from sensors, it transmits this data to the cloud application. Alternatively, it may receive a command from the application and send data to the end device. This process aligns with the application layer in the OSI model.

Here are the most typical IoT application layer protocols:

• MQTT
• HTTP/HTTPS
• CoAP
• AMQP
• WebSockets
• DDS
• XMPP
• OPC UA
• JSON-RPC and XML-RPC
• GraphQL
• WebRTC

From this entire IoT protocols list, some cover several levels of the OSI model, including the IoT modification. It’s because their goal is to solve all data transfer process issues. Yet, some protocols serve specific, well-defined tasks.

The connectivity architecture of the 2Smart Standalone automation platform.

Choose Your Perfect IoT Protocol with WebbyLab

As you can see, there are numerous internet of things protocols at your disposal. However, choosing the best ones for your project is sometimes overwhelming. Consider this article as your handbook on IoT’s most common communication means.

If you need help deciding which Internet of Things protocols suit you best, rely on WebbyLab’s expertise. Contact our team to discuss your project and select your perfect connectivity solutions.