Zero Trust Identity Consolidation: A Governance Framework for Transitional Identity Risk in Hybrid Microsoft Environments

Zero Trust identity architecture and large-scale AD and tenant consolidation are usually planned as separate initiatives, but they are the same problem viewed at different points in time. A consolidation that does not explicitly govern its transitional state (sIDHistory grants, dual-directory legacy protocol support and migration-era standing privilege) can operate for months or years with a larger attack surface than either its pre- or post-migration architecture. The ZTIC framework introduces no new technical controls; its contribution is sequencing and ownership discipline, treating the migration window as a governed state with a named owner, a register of every transitional exception and explicit exit criteria. The principal limitations are that the framework has been illustrated on a single composite rather than validated empirically, that it does not reduce remediation cost, and that it presumes resolvable ownership. Future work should apply ZTIC prospectively across multiple independently tracked organizations and test the maturity model against a broader sample. For practitioners, the immediate step is not a tool purchase but establishing the sIDHistory and standing-privilege register, with an owner independent of the migration team, before the next migration wave begins. As AI agents join the identity estate and act with the access they are given, that discipline becomes a precondition: the transitional state is the access baseline every agent will inherit.

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