What distinguishes a scan of interest from a sequential port scan?

A scan of interest is specifically designed to target particular Industrial Control System (ICS) ports that are crucial for the integrity and security of the infrastructure. This focus allows organizations to concentrate their scanning efforts on the ports most relevant to their systems rather than performing a broad sweep that may cover less critical areas. By honing in on these key ports, a scan of interest can yield more actionable insights and help in identifying vulnerabilities or threats directly associated with the functionality of the ICS.

In contrast, a sequential port scan generally involves scanning ports in a specific order, which may not necessarily target those most relevant to the specific security needs of ICS. Sequential scans can be less efficient as they may include a multitude of non-essential ports, leading to longer scan times without delivering targeted insights. The nature of sequential scans also means they can sometimes allow adversaries to predict the scan behavior and potentially evade detection or response.

The other options touch on aspects of scanning practices but do not accurately represent the distinguishing features of a scan of interest compared to sequential scans. For instance, the specific targeting of essential ports sets a scan of interest apart, providing a strategic advantage in the monitoring and securing of critical infrastructure.