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Version: 2.2.1-preview

AD-SUB-09 - Distinct first two octets (/16 networks) count should be retrievable

Michael SouleMerill Fernando
Contributed by Michael Soule with Merill FernandoAll contributors →

Overview​

Understanding /16 network distribution helps:

  • Network planning: Identify how many major network blocks are in use
  • Segmentation analysis: Understand logical network boundaries
  • Capacity assessment: Determine available /16 networks
  • Documentation: Support network architecture documentation

Each /16 represents a major network segment (65,534 hosts).

Security Recommendation​

  • Document the purpose of each /16 network block
  • Plan /16 allocation to support organizational structure
  • Reserve /16 blocks for future expansion
  • Review /16 utilization during network planning

How the Test Works​

This test extracts the first two octets from all IPv4 subnets and counts the distinct /16 networks.

  • Test-MtAdSubnetFirstOctetCount - Analyzes first octets
  • Test-MtAdSubnetFirstThreeOctetsCount - Analyzes /24 networks
  • Test-MtAdSubnetTotalCount - Counts total subnets

Test Metadata​

FieldValue
Test IDAD-SUB-09
SeverityInfo
SuiteActive Directory
CategoryAD.Site
PowerShell testTest-MtAdSubnetFirstTwoOctetsCount
TagsAD, AD-SUB-09, AD.Site

Source​

  • Pester test: tests/ad/site/Test-MtAdSubnetFirstTwoOctetsCount.Tests.ps1
  • PowerShell source: powershell/public/ad/site/Test-MtAdSubnetFirstTwoOctetsCount.ps1