2026年最新のISA ISA-IEC-62443リアル試験問題集PDF [Q48-Q68]

One of the primary goals of providing a framework that addresses secure product development lifecycle requirements is to ensure that security policies and procedures are well-documented. This objective is crucial because it establishes a structured and standardized approach to security that is integrated throughout the development process of software or systems. This framework helps in aligning the development process with security best practices, thereby mitigating risks associated with security vulnerabilities. Documentation of security policies and procedures ensures that security considerations are consistently applied and that compliance with relevant standards, such as ISA/IEC 62443, is maintained. This foundational approach supports the overall security posture by embedding security considerations directly into the lifecycle of product development, rather than addressing security as an afterthought.

Foundational Requirement 6 (FR 6), Timely Response to Events (TRE), as described in ISA/IEC 62443-3-3, requires that the system detect and respond to security-relevant events, including notifying the proper authority or personnel about security violations in a timely manner. This enables rapid incident response, containment, and recovery actions, all of which are critical to minimizing damage.
Reference: ISA/IEC 62443-3-3:2013, Section 4.3.3.6 (FR 6: Timely Response to Events).

One of the trends that has increased the security risks for industrial automation and control systems (IACS) is the integration of these systems with business and enterprise systems, such asenterprise resource planning (ERP), manufacturing execution systems (MES), and supervisory control and data acquisition (SCADA). This integration exposes the IACS to the same threats and vulnerabilities that affect the business and enterprise systems, such as malware, denial-of-service attacks, unauthorized access, and data theft. Moreover, the integration also creates new attack vectors and pathways for adversaries to compromise the IACS, such as through remote access, wireless networks, or third-party devices. Therefore, the integration of IACS with business and enterprise systems is a trend that has caused a significant percentage of security vulnerabilities. References: ISA/IEC 62443 Standards to Secure Your Industrial Control System, page 1-2.

According to the ISA/IEC 62443 standard, the connections between security zones are called conduits. A conduit is defined as a logical or physical grouping of communication channels connecting two or more zones that share common security requirements. A conduit can be used to control and monitor the data flow between zones, and to apply security measures such as encryption, authentication, filtering, or logging. A conduit can also be used to isolate zones from each other in case of a security breach or incident. A conduit can be implemented using various technologies, such as firewalls, routers, switches, cables, or wireless links.
However, these technologies are not synonymous with conduits, as they are only components of a conduit. A firewall, for example, can be used to create multiple conduits between different zones, or to protect a single zone fromexternal threats. Therefore, the other options (firewalls, tunnels, and pathways) are not correct names for the connections between security zones. References:
* ISA/IEC 62443-3-2:2016 – Security for industrial automation and control systems – Part 3-2: Security risk assessment and system design1
* ISA/IEC 62443-3-3:2013 – Security for industrial automation and control systems – Part 3-3: System security requirements and security levels2
* Zones and Conduits | Tofino Industrial Security Solution3
* Key Concepts of ISA/IEC 62443: Zones & Security Levels | Dragos4

MODBUS TCP/IP, a widely used communication protocol in industrial control systems, uses TCP port 502 by default.
“Modbus TCP/IP operates on TCP port 502, and this port should be monitored and protected to prevent unauthorized commands to critical control systems.”
– ISA/IEC 62443-3-3:2013, Annex A – Communication Protocols
This makes port 502 a high-value target for attackers, which is why it must be secured via firewalls and access control.
References:
ISA/IEC 62443-3-3:2013 – Annex A
MODBUS Application Protocol Specification v1.1b

A security policy refers to internal rules that govern how an organization protects critical system resources, such as industrial control systems (ICS). A security policy defines the objectives, scope, roles, responsibilities, and requirements for securing the ICS environment, as well as the procedures and guidelines for implementing, monitoring, and enforcing the security measures. A security policy also establishes the baseline for assessing and managing the security risks to the ICS, and for ensuring compliance with relevant standards, regulations, and best practices. A security policy is a key component of the ICS security program, and it should be documented, communicated, and reviewed regularly.
The other choices are not correct because:
* A. Formal guidance. Formal guidance refers to external sources of information and recommendations that can help an organization improve its ICS security posture, such as standards, frameworks, guidelines, and best practices. Formal guidance is not an internal rule, but rather a reference that can be used to develop, implement, and evaluate the security policy and controls. For example, the ISA/IEC
62443 series of standards provide formal guidance on how to secure ICS from cyber threats1.
* B. Legislation. Legislation refers to external laws and regulations that impose legal obligations and penalties on an organization for its ICS security performance, such as the NERC CIP standards for the electric sector2, or the EU NIS Directive for critical infrastructure operators3. Legislation is not an internal rule, but rather a compliance requirement that must be met by the organization. Legislation may also influence the security policy and controls, as the organization needs to align its security objectives and practices with the legal expectations and consequences.
* D. Code of conduct. A code of conduct refers to a set of ethical principles and values that guide the behavior and decision-making of an organization and its employees, such as honesty, integrity, respect, and accountability. A code of conduct is not an internal rule for protecting critical system resources, but rather a general norm for conducting business and maintaining a positive reputation. A code of conduct may also support the security policy and culture, as it can foster a sense of responsibility and trust among the ICS stakeholders.
References:
1: ISA/IEC 62443 Standards to Secure Your Industrial Control System
2: NERC Critical Infrastructure Protection Standards
3: EU Network and Information Systems Directive

IT systems and IACS have different security priorities, requirements, and challenges. According to the ISA/IEC 62443 standards, the security priority for IT systems is confidentiality, which means protecting the data from unauthorized access or disclosure. The security priority for IACS is integrity, which means ensuring the accuracy and consistency of the data and the functionality of the system. A loss of integrity in an IACS can have severe consequences, such as physical damage, environmental harm, or human injury. Therefore, IACS cybersecurity must address safety issues, which are not typically considered in IT security. Safety is the ability of the system to prevent or mitigate hazardous events that can cause harm to people, property, or the environment. The ISA/IEC 62443 standards provide guidance and best practices for ensuring the safety and security of IACS, as well as the availability and reliability of the system. Availability is the ability of the system to perform its intended function when required, and reliability is the ability of the system to perform its intended function without failure. These properties are also important for IT systems, but they may have different trade-offs and implications for IACS. For example, an IACS may have stricter performance and availability requirements than an IT system, as a delay or disruption in the IACS operation can affect the industrial process and its outcomes. Additionally, an IACS may have longer equipment lifetimes and less frequent maintenance windows than an IT system, which can make patching and updating more difficult and risky. Furthermore, an IACS may use different technologies and architectures than an IT system, such as legacy devices, proprietary protocols, or specialized hardware. These factors can create compatibility and interoperability issues, as well as increase the attack surface and complexity of the IACS. Therefore, IT security solutions and practices may not be sufficient or suitable for IACS, and they may need to be adapted or supplemented by IACS-specific security measures. The ISA/IEC 62443 standards address these differences and provide a comprehensive framework for securing IACS throughout their lifecycle.
References: 1: Security of Industrial Automation and Control Systems – ISAGCA 2: ISA/IEC 62443 Series of Standards – ISA 3: ISA/IEC 62443 Series of Standards | ISAGCA 4: Securing IACS based on ISA/IEC 62443
– Part 1: The Big Picture
* The key differences between IT (Information Technology) systems and IACS (Industrial Automation and Control Systems) are centered on their primary security objectives and operational requirements:
* Option A: The IACS security priority is integrity. This is crucial because any unauthorized modification of data or commands can lead to severe operational disruptions and safety hazards.
* Option C: IACS cybersecurity must address safety issues. Safety is a primary concern in IACS environments where process disruptions or malfunctions can result in harm to human operators or damage to equipment. The primary security priority in traditional IT systems is often confidentiality, not availability as stated in Option B, and routers are commonly used in IACS networks, contrary to Option
D.

Authorization security policy is the primary factor that determines access privileges for user accounts. Authorization security policy is the function of specifying access rights or privileges to resources, which is related to general information security and computer security, and to accesscontrol in particular1.
Authorization security policy defines who can access what resources, under what conditions, and for what purposes. Authorization security policy should be aligned with the business objectives and security requirements of the organization, and should be enforced by appropriate mechanisms and controls. Authorization security policy should also be reviewed and updated regularly to reflect changes in the environment, threats, and risks2. Authorization security policy is an essential part of the ISA/IEC 62443 standard, which provides a framework for securing industrial automation and control systems (IACS). The standard defines four security levels (SL) that represent the degree of protection against threats, and specifies the security capabilities that should be implemented for each SL. The standard also provides guidance on how to conduct a security risk assessment, how to define security zones and conduits, and how to apply security policies and procedures to the IACS environment34 . References:https://bing.com/search?q=authorization+security+policy
https://learn.microsoft.com/en-us/aspnet/core/security/authorization/policies?view=aspnetcore-7.0

IACS stands for “Industrial Automation and Control Systems.” The ISA/IEC 62443 series defines IACS as systems used for industrial automation, process control, and related functions. These include systems such as Distributed Control Systems (DCS), SCADA systems, and PLCs. The term encompasses all electronic systems, networks, and equipment used to automate industrial processes.
Reference: ISA/IEC 62443-1-1:2007, Section 3.2.1 (Definitions and Abbreviations); Glossary entry for
“IACS.”

The OSI model defines 7 layers for standardizing communications in network systems. The Transport Layer is responsible for reliable data transfer between end systems, including flow control, error correction, and segmentation. It sits between the Network Layer and the Session Layer.
The correct OSI model from top to bottom is:
Application
Presentation
Session
Transport # Missing layer
Network
Data Link
Physical
“The transport layer provides transparent transfer of data between end users, ensuring complete data transfer.”
– ISA/IEC 62443-3-3:2013, Annex A – Communications Stack and Layered Security Concepts Understanding the OSI model is crucial when designing secure industrial networks, as ISA/IEC 62443 advocates for layered defense (“defense in depth”) at all levels.
References:
ISA/IEC 62443-3-3:2013 – Annex A
ISA/IEC 62443-1-1:2007 – Section on OSI Reference Model

One of the most frequent mistakes in cybersecurity management-according to ISA/IEC 62443 guidance-is focusing only on technological solutions and neglecting other critical components such as people, process, and culture. Effective cybersecurity management must include policies, training, incident response, and continual improvement, not just technical controls. This holistic approach is emphasized throughout the standards, particularly in the sections describing CSMS program elements and organizational responsibilities.
Reference: ISA/IEC 62443-2-1:2009, Section 4.2.3 (“Cybersecurity is not just a technology problem”); Section 6.2.4 (Organizational awareness and training).

CCSC stands for “Common Component Security Criteria.” In the ISA/IEC 62443 series, specifically in Part 4-
2, CCSC refers to a harmonized set of security criteria applicable to individual components within an IACS, such as embedded devices, network devices, host devices, and software applications. These criteria are used to ensure that each component meets a consistent baseline for cybersecurity, supporting overall system security.
Reference: ISA/IEC 62443-4-2:2019, Section 4.1 (Definition of CCSC); Glossary.

An asymmetric key is a feature of asymmetric cryptography, also known as public-key cryptography, which is a method of encrypting and decrypting data using two different keys: a public key and a private key. The public key can be shared with anyone, while the private key must be kept secret by the owner. The public key and the private key are mathematically related, but it is computationally infeasible to derive one from the other. Asymmetric cryptography can be used for various purposes, such as digital signatures, key exchange, and encryption. For example, if Alice wants to send a message to Bob, she can use Bob’s public key to encrypt the message, and only Bob can decrypt it using his private key. Alternatively, if Bob wants to prove that he is the author of a message, he can use his private key to sign the message, and anyone can verify it using his public key. Asymmetric cryptography has some advantages over symmetric cryptography, which uses the same key for both encryption and decryption. For instance, asymmetric cryptography does not require a secure channel to distribute the keys, and it can provide non-repudiation and authentication.
However, asymmetric cryptography also has some drawbacks, such as higher computational complexity, larger key sizes, and higher network overhead.
References:
ISA/IEC 62443-3-3:2018, Section 4.2.3.6.1, Cryptography1
ISA/IEC 62443-4-2:2019, Section 4.2.3.6.1, Cryptography
ISA/IEC 62443 Cybersecurity Fundamentals Specialist Study Guide, Section 5.3.1, Cryptography ISA/IEC 62443 Cybersecurity Fundamentals Specialist Exam Specification, Section 5.3.1, Cryptography

At layer 4 of the OSI model, also known as the transport layer, the application that will handle a packet inside a host is identified by a TCP/UDP port number. A port number is a 16-bit integer that is assigned to a specific application or service that runs on a host. Port numbers are used to multiplex and demultiplex the data streams that are exchanged between hosts and end systems. Multiplexing is the process of combining multiple data streams into one, while demultiplexing is the process of separating one data stream into multiple ones. Port numbers are part of the header of the transport layer protocol data unit (PDU), which is called a segment for TCP and a datagram for UDP. The header contains the source port number and the destination port number, which indicate the applications that are involved in the communication. For example, if a host sends a packet to another host using the HTTP protocol, which runs on port 80 by default, the source port number would be a random number chosen by the sender, and the destination port number would be 80. The receiver would then use the destination port number to demultiplex the packet and deliver it to the HTTP application.
Port numbers are divided into three ranges: well-known ports (0-1023), registered ports (1024-49151), and dynamic or private ports (49152-65535). Well-known ports are reserved for common and standardized applications and services, such as HTTP (80), FTP (21), and SSH (22). Registered ports are assigned by the Internet Assigned Numbers Authority (IANA) to specific applications and services that request them, such as Skype (49175) and Minecraft (25565). Dynamic or private ports are not assigned by any authority and can be used by any application or service that needs them, such as ephemeral ports that are used for temporary connections.
The other options are not valid identifiers for the application that will handle a packet inside a host at layer 4 of the OSI model. A TCP/UDP application ID is not a term that is used in the OSI model or the TCP/IP model. A TCP/UDP host ID is not a term that is used in the OSI model or the TCP/IP model, and it would be more appropriate for layer 3, which is the network layer, where the host is identified by an IP address. A TCP
/UDP registry number is not a term that is used in the OSI model or the TCP/IP model, and it would be more appropriate for layer 5, which is the session layer, where the registry number is used to identify a session between two hosts.
References:
Transport Layer | Layer 4 | The OSI-Model1
OSI model – Wikipedia2
What is Layer 4 of the OSI Model? | Glossary | A10 Networks3
What Are the 7 Layers of the OSI Model? | Webopedia4

Separation of duties is a security principle that aims to prevent fraud, errors, conflicts of interest, or misuse of resources by dividing critical tasks or functions among different people or teams. It is one of the foundational requirements (FRs) of the ISA/IEC 62443 standards for securing industrial automation and control systems (IACSs). According to the ISA/IEC 62443-2-1 standard, separation of duties includes the following system requirements (SRs):
* SR 2.1: Security management policy
* SR 2.2: Personnel security
* SR 2.3: System development and maintenance
* SR 2.4: Incident response and recovery
* SR 2.5: Compliance and review
Among these SRs, the one that is most related to the example of system development and maintenance is SR
2.3. SR 2.3 requires that the IACS shall provide the capability to ensure that the development and maintenance of the system and its components are performed in a secure manner. This means that the IACS should have a mechanism to control the access and authorization of developers, testers, integrators, and maintainers who work on the system and its components. It also means that the IACS should have a mechanism to verify and validate the quality and security of the system and its components before, during, and after the development and maintenance processes.
Therefore, an example of separation of duties as a part of system development and maintenance is that changes are approved by one party and implemented by another. This ensures that the changes are authorized, documented, and reviewed by someone who is not involved in the implementation. This reduces the risk of introducing errors, vulnerabilities, or malicious code into the system and its components.
References:
ISA/IEC 62443-2-1:2010, Security for industrial automation and control systems – Part 2-1: Establishing an industrial automation and control systems security program1 ISA/IEC 62443 Cybersecurity Fundamentals Specialist Certificate Program2 ISA/IEC 62443 Cybersecurity Library3 Using the ISA/IEC 62443 Standards to Secure Your Control Systems4

Transport Layer Security (TLS) is the standard protocol for securing web communications, including HTTP over TLS (HTTPS) in web browsers. TLS provides encryption, authentication, and data integrity, and has replaced SSL as the primary means of securing browser-based communications.
Reference: ISA/IEC 62443-3-3:2013, Section 4.2.3.7 (“Use of TLS for secure communication”); NIST SP
800-52 Rev. 2.