Chapter 2. Industrial IoT Dataflow and Security Architecture

"Ensuring that the devices and systems connected to the internet are secure is a key to ensuring the safety and reliability of industrial operations."

             – Dr. Richard Soley, Executive Director, Industrial Internet Consortium (IIC)

The sheer scale and complexity of IIoT demands a systematic approach to secure the system architecture. When the degree of complexity is high, decomposing the security paradigm into subdomains helps to manage and mitigate risks. This decomposition is particularly useful to use cases involving several technologies, and spanning across multiple organizational boundaries (a common scenario in IIoT).

Industrial systems last for decades. This further necessitates to plan for protecting industrial IoT systems and assets against both current and future threats.

This chapter presents in-depth insights into IIoT (big) data flows and IIoT reference architectures, and introduces the industrial internet security...

Primer on IIoT attacks and countermeasures

Understanding the dynamics involved in industrial IoT attacks is crucial to perform security risk analysis and mitigation. Threat modeling is commonly used as a security countermeasure, and has been discussed later in this chapter. Attack and fault trees are two methodologies useful to develop security threat models and to communicate the risk of an attack.

In the real world, most attacks are highly customized to target specific vulnerabilities in IoT products and connectivity. Many attacks target zero-day vulnerabilities. In the case of zero-day vulnerabilities, an exploit already exists and can be easily proliferated through the internet or corporate networks to create a snowball effect. Since IIoT involves significant investment and skills, most attacks involve nation state threat actors, who are motivated to create a major impact.

Some common types of attacks in the IIoT context are as follows:

• Malware-triggered ransomware
• Wired and wireless scanning...

Trustworthiness of an IIoT system

As already noted in this book, the concept of securing cyber-physical systems is a superset of what we normally understand by cybersecurity and information security.

To properly represent the scope of IIoT security, the term trustworthiness is used (NIST-CPS) (IIC-IISF). A working definition of trustworthiness for CPS, according to NIST-CPS, is:

"Trustworthiness is the demonstrable likelihood that the system performs according to designed behavior under any set of conditions as evidenced by characteristics including, but not limited to, safety, security, privacy, reliability and resilience."

Trustworthiness of an IIoT system is an important stakeholder expectation. To make an IIoT system trustworthy, security characteristics of both IT and OT domains must be combined (IIC-IISF). As shown in Figure 2.6, the key characteristics of a trustworthy IIoT system combine the elements of IT trustworthiness (privacy, security, reliability, and resilience) and OT trustworthiness...

Industrial big data pipeline and architectures

Data is the prime asset in the IIoT value chain. Industrial devices such as sensors, actuators, and controllers generate state and operational data. The information inherent in this industrial big data enables a variety of descriptive, prescriptive, and predictive applications and business insights. This end-to-end flow of data, from the point of ingestion, through information processing using various extract, transform and load (ETL) functions, applying AI and machine learning intelligence, up to the point of data visualization and business application, is collectively referred to as the industrial big data pipeline (shown in Figure 2.7):

Figure 2.7: Schematic illustration of the stages in Industrial Data flows

The preceding diagram is explained as follows:

• On-premise data sources: On-premise data includes usage and activity data – both real-time streaming data (data in motion) and historical/batch data from various data sources. Sensors and controllers...

Industrial IoT security architecture

In 2015, the IIC released the Industrial Internet Reference Architecture (IIRA) for IIoT systems (IIC-IIRA). It uses "ISO/IEC/IEEE 42010:2011 Systems and Software Engineering–Architecture Description" for architectural conventions and common practices. IIRA provides an architectural framework to analyze concerns, views, models, and so on with certain degrees of abstraction. The use of reference architectures helps to incorporate security by design. Architects can build use case-specific IIoT architectures on top of these reference architectures.

In this section, the four viewpoints of IIC's reference architecture are briefly discussed. These viewpoints simplify the understanding and decomposition of IIoT architectures. You can find an in-depth treatment of these viewpoints in (IIC-IIRA).

 Business viewpoint

The business viewpoint of an IIoT architecture helps to analyze and evaluate business-oriented concerns, such as the business objectives of adopting...

Summary

This chapter presented a primer of attacks, countermeasures, and threat modeling, which lays the foundation for effective risk analysis and mitigation. It also provided the readers with insights into the distinguishing characteristics of trustworthiness for IIoT systems and the functional components of the industrial big data pipeline.

IIoT systems are highly complex; this chapter presented IIoT architectural viewpoints and patterns as developed by the IIC to provide you with a crisp understanding of end-to-end IIoT system components. Based on usage, operations, and functional domains, the IIoT security architecture was decomposed into a four-tier security model, which has been further elaborated in the subsequent chapters of the book.