The Cybersecurity and Infrastructure Security Agency has issued the first part of its latest guide that provides an overview of microsegmentation as part of CISA’s efforts to help federal civilian executive branch agencies implement zero trust architectures.

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What Is the Purpose of CISA’s Zero Trust Microsegmentation Guidance?
CISA said Tuesday the document titled “Microsegmentation in Zero Trust, Part One: Introduction and Planning” is part of its Journey to Zero Trust series and covers key concepts associated with microsegmentation, which seeks to reduce the attack surface, limit lateral movement and boost visibility.
“So many organizations, both on the federal side and in the private sector, we saw make early investments in zero trust network access tools, or SASE tools – secure access service edge –as part of their early implementation,” Shelly Hartsook, an acting associate director within CISA’s cybersecurity division, told Federal News Network in an interview.
“And there is a value in those bringing those tools into the toolbox and initially implementing them. This guidance can help organizations make the most of those technology investments and how they’re configured and really used across the enterprise,” Hartsook added.
The document also offers recommended actions to advance zero trust principles and modernize network security.
The agency intends to launch a subsequent technical guide to provide implementatation teams with technical considerations and detailed implementation scenarios.
Phased Approach to Microsegmentation
The document provides agencies with a phased approach when transitioning portions of their enterprise to microsegmentation.
The phased approach includes identifying candidate resources for segmentation; identifying dependencies for selected candidate resources; determining appropriate segmentation policies; and deploying updated segmentation policies.
Hartsook noted that implementing microsegmentation requires organizations to do careful planning from the start.
“So really understanding how to apply it and having a deliberate strategy architecture and planning is critical to doing this in a way that achieves the cybersecurity intent without mucking up your just normal business with your organization,” she told FNN.