Cyber-Physical Systems (CPS) vs IoT: What’s the Difference?

What Is the Difference Between CPS and IoT

Cyber-Physical Systems (CPS) and the Internet of Things (IoT) are distinct from one another. Yet, over time, they have come to share attributes that make them seem more similar.

Since its inception, CPS has focused on the integration of the physical world with computer systems to monitor, coordinate, and control physical processes. This integration could occur over the Internet, but it was not necessary.

According to the National Institutes of Health’s National Library of Medicine, the term cyber-physical systems was introduced in 2006 to describe “an orchestration of computers and physical systems” where “embedded computers monitor and control physical processes, usually with feedback loops, where [these] processes affect computations and vice versa.”

In simple terms, CPS combines computer-based algorithms (the “cyber” part) and physical processes or components (the “physical” part) to perform a task or solve a problem in the real world. These systems play a crucial role in improving efficiency, automation, and reliability in the industries of public infrastructure, manufacturing, transportation, and healthcare.

Connected devices, on the other hand, have always emphasized the networking of ‘things’ that exchange data, typically via the internet. Networked physical objects, such as devices, vehicles, appliances, etc., have embedded sensors, software, and connectivity. Together, these elements enable them to collect and exchange data over the internet. Connected devices do not incorporate compute in the way that cyber-physical systems do.

High-Level Convergence

Today, at a high level, the lines between the two realms have blurred, as CPS has moved more into the online world (networking) as connected devices expand into control over the physical.

You can see this blurring of the lines in Gartner’s latest definition of CPS. In February 2025, Gartner noted that it defines CPS as “engineered systems that orchestrate sensing, computation, control, networking and analytics to interact with the physical world (including humans).”ⁱ Simultaneously, intelligent digital systems now manage physical outcomes in ways they never did before. As an example, they can adjust heating and lighting in a ‘smart building’ based on real-time occupancy, reducing energy consumption, and maximizing comfort.

Nevertheless, a few major differences remain.

Differences Between Cyber-Physical Systems and the Internet of Things

Despite their seeming convergence, three main differences remain between cyber-physical systems and the Internet of Things.

First, cyber-physical systems are rarely fully autonomous. Smart device systems are growing increasingly autonomous. With CPS, there is always some level of human intervention. For example, self-driving cars can make navigation decisions through a combination of sensors, cameras, radar, lidar (remote sensing), GPS, and a sophisticated onboard computer system. Yet, they still must be able to communicate with their human passengers. Given the prominent news stories of people crashing their semi-autonomous cars while not paying attention to the road, one can expect these cyber-physical systems to always request human intervention when they encounter scenarios which are challenging or ambiguous.

By contrast, a smart refrigerator can make decisions and take actions on its own. Its thermostat (physical component) interacts with the temperature inside the machine and is also connected to a computer system (cyber component) that processes information and makes decisions based on the data it receives from the thermostat. The computer system can adjust the thermostat settings to either maintain or change to the desired temperatures in the main compartment and the freezer portion.

The second difference is that cyber-physical systems require real-time data processing and analysis as well as closed-loop actions to ensure proper functioning and process performance. Internet-enabled things do not require these things. Moreover, the deployment of CPS in critical industries means that system failure can have significant consequences. Connected devices, on the other hand, have a greater focus on productivity and convenience, not critical physical rigor.

The third difference is that CPS are far more costly to replace due to complexity. Think of an electric grid or other utilities company. With tightly coupled computational elements and physical processes – often with multiple interacting components like sensors, actuators, and complex control systems – they often require technicians to replace the entire system or a significant part of it. Technicians must act carefully to ensure everything is operational and integrated following a replacement. With connected devices, a technician normally replaces just a single faulty device. Not only is the device simpler and the replacement of one device cheaper than replacement of an entire system, but also the technician performing the work needs far less domain expertise, making them a less expensive resource.

Similar Trends Shaping Both System Types

The landscape for both areas is expected to mature and expand in similar ways over the next several years, with three major drivers at the heart of their expansion. These include increased integration of AI and machine learning, enhanced security measures, and the continued rise of cloud and edge computing. Here’s how:

AI and Machine Learning Integration will:

• Enable intelligent algorithms, automation, and data-driven decision-making.
• Automatically analyze data from connected devices to optimize processes, predict potential issues, and personalize user experiences.
• See its most popular use cases for optimizing energy consumption in smart buildings, predicting maintenance needs for industrial equipment, and personalizing healthcare recommendations based on patient data

AI and Machine Learning Integration in CPS will:

• Enhance security by detecting anomalies in system and actuator activity.
• Predict threats via more rigorous data analysis.
• Improve access control by applying proactive threat detection, personalized access policies, and automated responses.

Security will Improve because of:

• Organizations addressing the massive growth in the number of connected devices by making security a top priority for deployments.
• IT teams incorporating stronger encryption protocols, multi-factor authentication, and blockchain-based security solutions.
• Security teams using AI-driven threat detection to help identify and mitigate potential cyberattacks on networks.

Security will improve in CPS because of:

• Security teams responding to the increased security risks brought on by growing interconnectedness of these systems. They will emphasize specialized security protocols for industrial systems, critical infrastructure, and cloud environments.
• Improved cloud security that addresses both multi-cloud and hybrid cloud environments. Specifically, organizations will adopt solutions and strategies for cloud security posture management (CSPM) and security orchestration, automation, and response (SOAR) systems.

Edge Computing will improve both in virtually the exact same way by:

• Enabling organization to process data closer to the source.
• Reducing latency, improve response times, and minimize bandwidth usage, especially in applications requiring real-time decision-making.
• Saving cost by performing computations and analysis locally, reducing the need to send all data to the cloud.
• Enhancing data privacy by processing sensitive information locally.

Unique Trends

Because of their near ubiquity and many systems’ ability to perform under low-power conditions, two additional trends are gaining traction. The first is LPWAN (low-power wide-area network) expansion. LPWAN enables long-range communication and low power consumption. It is ideal for asset tracking in industries like agriculture where a large number of devices with low power requirements are dispersed over extremely wide areas.

The other unique trend is the use of ‘digital twins.’ These virtual replicas of physical objects or systems allow for simulation, analysis, and optimization of processes in a virtual environment. Once proven there, operations teams can implement changes in the real world. Digital twins reduce risk and improve effectiveness for industries like healthcare, manufacturing, and smart cities.

Best Practices in Security

Cyber-physical systems are a subset of operational technology (OT). As such, when Forescout and organizations like CISA and NIST recommend best practices in OT, the practices automatically apply to CPS as well. Thus, in the following section, the references to OT include CPS automatically.

Connected ‘things’ and OT security follow similar practices in their processes to protect assets. However, when they get started, IT and security teams should focus on specific best practices for each separately.

For Connected Device Security, we recommend the following three best practices to start:

1. Discover and classify 100% of IP-connected devices: It’s essential to obtain complete visibility and device context of all endpoints across your network environment. To do this, use a cybersecurity platform that can discover all devices as soon as they enter your network. Since you must discover all devices, the technology you leverage should provide for devices that do not allow for agents. Agentless discovery will ensure that you capture everything.
2. Implement dynamic network segmentation and controls: Proper connected device security requires network segmentation and orchestrated incident response across all domains. To do this, you must be able to:
   • Correlate access with user identities (who is doing what, where, when and why)
   • Provision devices to dynamic network segments based on policies and real-time context
   • Map data flows to design segmentation policies and simulate them for non-disruptive deployment
   • Automate segmentation to reduce security and operational risk
3. Orchestrate security and enforce compliance: Rather than using traditional, expensive, single-purpose security solutions that cannot share knowledge or coordinate incident response, leverage a security solution that can share device context with other IT and security products. This will enable you to automate workflows and policy enforcement across disparate solutions. The benefits of taking this step include:
   • Increase security and overall device compliance
   • Reduce mean time to detect and respond
   • Increase ROI from your existing tools
   • Streamline updates to your configuration management database (CMDB)

For OT Security, we recommend these three best practices to start:

1. Implement access controls and user authentication: It’s crucial to enforce strong access controls and user authentication. This involves assigning unique user accounts and robust passwords. Additionally, employing multi-factor authentication adds an extra layer of security by requiring multiple forms of verification.
2. Implement network segmentation and isolation: Segmenting the OT network into smaller, isolated sections helps contain breaches and limits the spread of attacks within the network. This practice separates critical assets from non-critical ones, minimizing the attack surface and safeguarding sensitive information.
3. Regularly patch and update assets: Consistently updating and patching OT systems is vital to address vulnerabilities and defend against known exploits. Keeping track of vendor updates, security advisories, and specific patches for OT devices and applications is essential. Establishing a patch management process ensures timely deployment of updates while minimizing disruptions to critical operations.

How Forescout Helps

Forescout takes a Zero-Trust approach by combining complete device visibility, proactive network segmentation, and least-privilege access control of all digital assets – devices, users, apps, and workloads. The Forescout 4D Platform™ enables you to effectively manage cybersecurity, operational, and compliance risks across your environment by:

• Providing complete visibility into unmanaged devices as well as all IP-connected systems
• Assessing and identifying assets with factory-default or weak credentials and automating policy actions to enforce strong passwords
• Providing real-time insight into devices’ communication and risky behavior across the extended environment
• Segmenting devices into trusted zones by enforcing least-privilege access by zero trust policy
• Automating unified zero trust policy orchestration across multivendor environments and multiple network domains
• Eliminating security management silos to accelerate response and maximize the value of your investments in other security solutions
• Helping your organization proactively detect and reduce vulnerabilities and granularly enforce segmentation and network access rules, and immediately contain device threats while facilitating remediation

Employing non-disruptive approaches, Forescout extends its visibility from campus and data center networks to virtual servers, the cloud, and the OT environment. This expanded visibility enables organizations to identify devices that require passive monitoring and take proactive measures to secure those capable of supporting additional security controls.

This comprehensive approach ensures that organizations have real-time insights of all assets and can respond proactively to potential security threats.

Learn more about our approach to OT Security and the Forescout 4D Platform™.