Security Network Architecture and Protocols Flashcards

Which IEC standard specifically addresses security for industrial communication networks and system components in ICS?

Answer: IEC 62443

IEC 62443 is the international series of standards for industrial automation and control system cybersecurity.

What is the function of a data diode in an ICS security architecture?

Answer: One-way hardware-enforced data flow from OT to IT

A data diode enforces hardware-level unidirectional data flow, typically from OT to IT, preventing any return path for attacks.

In ICS environments, what does the term 'conduit' refer to in the context of IEC 62443?

Answer: A communication pathway between two security zones

In IEC 62443, a conduit is a logical grouping of communication channels connecting two or more security zones.

Which network architecture approach places an application-layer proxy between the OT network and external systems to inspect ICS protocol traffic?

Answer: Application-aware firewall or protocol-aware proxy

An application-aware firewall or protocol proxy inspects ICS-specific protocol commands (e.g., Modbus function codes) for anomalies.

What is the primary security risk of using a flat network architecture in an ICS environment?

Answer: Lateral movement allows attackers to reach all devices once inside

A flat network with no segmentation allows an attacker who compromises one device to freely move laterally to all other devices.

Which DNP3 feature was added in DNP3 Secure Authentication v5 to protect against spoofing?

Answer: Challenge-response HMAC authentication

DNP3 Secure Authentication v5 uses HMAC-based challenge-response to verify message origin and integrity.

What type of ICS network topology is most resilient to single-point-of-failure attacks on communication links?

Answer: Mesh topology

Mesh topology provides multiple redundant paths between nodes, so no single link failure isolates any device.