IT Explained

IT Explained:


What is IIoT?

IIoT stands for the Industrial Internet of Things and refers to a network of connected devices in the industrial sector. It is a subset of the Internet of Things (IoT). The defining characteristic of connected devices on IIoT networks is that they transfer data without human-to-human or human-to-computer interaction. Connected devices communicate through gateways, which are physical servers that filter data, and transmit it to other devices and software applications.

The terms IIoT and IoT refer to proprietary, standalone networks, as well as broader, global networks.

What is an IoT device?

The first connected device (circa 1982) was a Coca-Cola vending machine at Carnegie Mellon University in Pittsburgh, Pennsylvania. The machine was programmed to control operating temperature and to track the number of bottles in stock. A cable was run between sensors attached to the vending machine and the computer science department’s main computer. The computer was connected to the Advanced Research Projects Agency Network (ARPANET), the forerunner of today’s internet. Information about the vending machine stock was accessible to anyone connected to the ARPANET and who had access to Carnegie’s local ethernet.

The term IoT was not introduced until 1999, by Kevin Ashton, a technology researcher.

An IoT device connects to another device through an IoT gateway service, for example a wearable device that connects to a smartphone, which is the physical gateway to the device’s software functionality. This is an example of a standalone IoT system. In the broader IoT ecosystem, devices communicate via cloud-based gateways, for example remote sensors that transmit weather conditions to a weather bureau.

In the home, commercial, and industrial environments, IoT technologies include wearables, appliances, utility grids, security monitoring systems, weather prediction services, traffic and crowd control systems, vehicles, and lighting and heating applications.

The IIoT unpacked

In an IIoT system, sensors for temperature, movement, light, and pressure, for example, feed data to a Programmable Logic Controller (PLC), industrial control system (ICS), or Supervisory Control and Data Acquisition (SCADA) system. These systems deliver the information to an IIoT process. Then a function in the IIoT process delivers information to a device, for example a heater, security camera, light fitting, or pressure balancer.

Examples of IIoT devices in an IIoT network include sensors, computers, and machines used in manufacturing, agriculture, and mission-critical applications, for example nuclear and energy management systems.

Examples of IIoT applications include alerts about equipment malfunctions in a factory, remote monitoring of computer-chipped livestock on a commercial farm, and management of utility systems, for example transportation grids.

IIoT sensor data is used to provide actionable insights into physical events and the environment. In mission-critical systems, IIoT technologies may provide early warning alerts about the environment, for example excessive carbon monoxide levels in a factory.

Most IoT applications operate in the public cloud. Proprietary IIoT systems operate mainly in private clouds developed for commercial, government, and industrial organizations.

What is OT?

OT stands for operational technology. OT refers to the operational processes, hardware, and software used to monitor, control, and alter the behavior of devices and systems, for example the temperature in a room or a rail network. One goal is to automate these processes. 

Examples of OT devices include sensors, control valves, machines, transmitters, actuators, cameras, electronic locks, engines, thermostats, factory and plant equipment, embedded systems, Human-Machine Interfaces (HMI), and robots. OT systems communicate mainly over point-to-point networks. 

OT applications include telecommunications, electronics, chemical processing, paper manufacturing, power and nuclear plant management, waste management, mining, water treatment, building management industry, and oil and gas processing. 

OT-IIoT convergence

The term OT-IIoT describes the evolution of OT systems to remotely manage physical devices and systems, using IoT and IIoT technologies. OT systems use specialized software standards and protocols, for example Distributed Network Protocol 3, Modbus, EnOcean, and LonWorks. These protocols are designed to integrate with traditional IoT and IIoT protocols. 

Traditionally, the biggest challenge for OT systems was that components were often designed without built-in IT security. In OT systems, hard-wired control systems performed safety and security functions. The IIoT is changing the way OT devices are secured, using cloud-based security applications. 

For example, these days OT increasingly makes use of digital twin devices, which are the equivalent of development sandboxes or virtual environments, to test applications. Twin devices are digital representations of real systems and devices. In the manufacturing and industrial sectors, digital twin devices are used to test new operations on critical assets without affecting the “real” asset. Updates, repairs, and new functionality can be made on physical devices and their impact can be analyzed before deploying software or hardware changes. Twinning is also used to run simulations using different data inputs. The goal is to observe and optimize the behavior of systems and devices in different scenarios. 

What is the difference between IIoT and OT?

Traditionally, OT focused on the operational management of physical devices, mainly in the industrial sector.

The lines between IoT, IIoT, and OT systems are blurring. Modern OT applications utilize IIoT networks to monitor and manage physical devices and operational applications. One example is the aggregation of data in OT systems from multiple sources, including physical sensors, databases, and remote gateways. Analyzing this data in OT systems used to be primarily a manual process but now IIoT software is used to automate data collection and analysis. 

Where are IIoT systems used?

Utility companies and mission-critical systems use the IIoT to manage outages or to identify heavy demands on resources, for example electricity grids and nuclear plants. IIoT technology can improve the reliability of resource distribution. IIoT-analytic software detects faults, alerts businesses about outages, and suggests repairs.

Fleet management businesses use IIoT applications to track vehicles, supplies, drivers, and workflow efficiency. IIoT tracking enhances operational efficiency and enables the remote support of offsite workers.

In the agriculture industry, the analytic and predictive capabilities of IIoT help farmers to make informed decisions about when to harvest. IIoT sensors gather data about soil and weather conditions and suggest optimum fertilizing and irrigating schedules. Embedded computer chips monitor the health and location of livestock.

In the manufacturing industry, IIoT is used for asset and supply chain management. It enables the centralized management of assets, and supports real-time communication between suppliers, manufacturers, storage facilities, delivery companies, and customers. IIoT applications monitor maintenance programs across the supply chain and enable remote communication. IIoT minimizes human error in inventory management. IIoT asset management requires less human labor and reduces the costs of goods and services.

Uses for IIoT technologies

IoT technologies used for industrial applications can increase productivity. For example, using specialized software on mobile devices enables remote workers to stay in touch with their head offices, to track tasks, and to access information they need to do their jobs. Repetitive tasks can be automated.

IIoT endpoint security can provide automated alerts about breach attempts. Automated alerts enable cost-effective 24/7 security monitoring.

Organizations can use applications like Shodan to check whether their connected devices are vulnerable to cybercriminals.

Predictive maintenance processes can lower costs. Smart sensors that monitor equipment and products can identify mechanical breakdowns and system failures, and mitigate downtime.

Smart networks can increase hardware efficiency. For example, “listeners” on Low-Power Wide-Area Networks (LPWANs) can extend battery life for devices that use batteries by listening for new messages at staggered intervals instead of being constantly powered on. 

How do IIoT technologies work?

IIoT protocols and standards

The IIoT, focused on industrial applications, is a subset of the IoT. The IIoT and IoT adopt similar basic standards and protocols. IIoT standards and protocols are specific to industrial application.

A network has three main layers: the physical layer that includes sensors and physical devices, the network layer that connects devices and that is the IoT or IIoT gateway, and the application layer that delivers the data. Components in these layers are managed by specialized protocols and standards, for example regarding infrastructure (IPv4/IPv6, RPL, QUIC), communications (Wi-Fi, Bluetooth, LPWAN, NFC, Zigbee, DigiMesh), data (MQTT, CoAP, AMQP, SMCP, XMPP, LLAP, REST, SOAP), devices (TR-069, OMA-DM, OMA LwM2M), and security (OTrP, X.509).

The five main types of communication and connectivity protocols used by networks are cellular, Wi-Fi, LoRaWAN (Long Range Wide Area Network), Zigbee, and Bluetooth.

The range for communication signals can vary a lot. The range variation depends mainly on whether there are obstructions between a signal and a device, and the protocol used. The IEEE 802.11x standard defines the speed and range of signals transmitted between wireless clients.

The range for cellular technologies (GSM 3G/4G/5G) is 20-125 miles but its wide application range comes at a high price. Wi-Fi provides fast data transfers over shorter distances between 150-300 feet. Zigbee is used mainly for industrial applications. It is a low-power, low-data-transmission network with a range between 30–350 feet.

Bluetooth uses the Bluetooth Low-Energy (BLE), or Bluetooth Smart protocol for IoT applications. Bluetooth devices are divided into three classes. The range for Bluetooth connections is between 3-330 feet. Class 1 Bluetooth devices may transmit a signal up to 330 feet. A Class 3 Bluetooth device may only transmit a signal about 3 feet.  Wearables commonly use Bluetooth protocols for connections.

LoRaWAN can support millions of low-power connected devices, for example in a smart city system. Its range is 2-15km. But, in a 2017 experiment by Dutch Telco KPN, a LoRaWAN signal from a hot air balloon covered 436 miles.

On IIoT networks, Message Queue Telemetry Transport (MQTT) is a common standard that manages the data flow between sensors and applications. Data Distribution Service (DDS) is a standard that supports high-performance machine-to-machine (M2M) connections, which are the point-to-point connections between devices. 

Device management

Basic IIoT device management tasks includes verifying the authenticity of enrolled devices, resetting decommissioned devices, reconfiguring new devices, diagnosing software bugs and operational anomalies, updating software, suggesting maintenance schedules, and monitoring data usage and uptime.

The latest trend in device management is to include context-aware functionalities in traditional device management solutions. Context-aware recommender systems (CARS) help users to make decisions about how their devices operate based on various scenarios. Context-aware rules of operation can help to define how a device is used in the real world. A device that is used in a particular context, for example remotely or in a building, can be configured to send an alert under adverse conditions specific to its state. One example is a connected vehicle being driven in inclement weather, something that would not affect a driverless truck used on a production line in a factory. Another example is when a device requires location information to operate. When a device is unable to use GPS, its predefined state – in this case, one that requires GPS functionality – will alert users that it is unable to operate as expected. 

Connectivity and networking

Some of the functions of device connectivity and network management include limiting data usage, throttling data where necessary, providing usage measurements and alerts, customizing content, securing content, limiting access to business-critical information, and allowing custom features based on roles.

IoT devices, IIoT devices, and sensors communicate through a gateway that allows them to share data over a network, either device-to-device or device-to-cloud. A smartphone, wearable, factory robot, and heart pacemaker all communicate differently. The gateway enables communication between devices that use different types of protocols. A gateway also reduces the range over which a sensor needs to communicate because it can forward sensor data directly to a device that is out of a sensor’s immediate range.

The concept of edge computing is central to IoT and IIoT gateways. IIoT systems process large amounts of data from many sources across remote locations. Using edge data modeling, critical data in an IIoT system is pre-processed and filtered at the gateway. This helps to prevent bottlenecks.    


The IIoT Safety and Security Protocol developed by the World Economic Forum is aimed at addressing IIoT security issues. The North American Electric Reliability Corporation (NERC) establishes cybersecurity standards for power systems and suppliers in the U.S. and the National Institute of Standards and Technology (NIST) provides guidelines for securing industrial control systems. The Chemical Facility Anti-Terrorism Standards (CFATS) defines security regulations for high-risk IIoT systems, for example at chemical factories and refineries. 

What are the most common IIoT connectivity options?

Networks are usually categorized according to the coverage they provide. Near Field Communication (NFC) is a low-speed network with a range of a few inches. It is commonly used in contactless payment systems. Wide area networks (WAN) cover large geographical areas and incorporate smaller networks, for example local area networks (LAN). A LAN typically covers a building, for example an office block. A vehicle area network (VAN) connects emergency response vehicles to cameras, radar, and GPS systems.

Networks can also be categorized according to the way they are configured, for example in a mesh, line, bus, star, or tree configuration. Mesh networks are popular for IoT systems because they are flexible and allow nodes to connect to other nodes without strict hierarchical rules.

IIoT challenges for organizations

The same vulnerabilities that affect computer hardware and software outside of IIoT systems affect the IIoT as well. Hardware defects, firmware and software bugs, lack of maintenance, faulty parts, and the use of devices in extreme conditions can contribute to device failures.

Despite efforts to combat cybercrime, the number of cyberattacks increases daily. Critics argue that the IoT and IIoT are particularly vulnerable to criminals. One reason for this is that smart devices are accessed, operated, and managed remotely.

For workers, widespread automation may result in a loss of jobs in some industries.

Cynical observers suggest that vendors will take advantage of the IIoT to build and sell redundant security applications to business owners who are not technology literate.


Experts suggest the IIoT will outstrip the IoT in terms of adoption. This is because manufacturing businesses have a strong incentive to improve their financial bottom line and return on investment, cut labor costs, and increase productivity. To do this, organizations need to invest in software to manage and monitor their networks.


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