A controlled interface must have interconnections among DoD information systems operating between DoD and non-DoD systems or networks.

The configuration of an AD trust relationship is one of the steps used to allow users in one domain to access resources in another domain, forest, or Kerberos realm. When a trust is defined between a DoD organization and a non-DoD organization, the security posture of the two organizations might be significantly different. If the non-DoD organization maintained a less secure environment and that environment were compromised, the presence of the AD trust might allow the DoD environment to be compromised also.