Why Hybrid Identity?
Most enterprises still run on-premises Active Directory (AD) but are moving workloads to Azure. Hybrid identity lets you bridge these environments so users have a single identity for both on-prem and cloud resources.
The goal: One username, one password, everywhere.
Options for Hybrid Identity
1. Azure AD Connect (Password Hash Sync)
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Most common method.
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Syncs user accounts and password hashes from on-prem AD to Entra ID.
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Passwords are verified in Azure, not on-prem.
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Provides single sign-on with Microsoft 365 and Azure apps.
Best for: Most organizations that want simplicity and minimal infrastructure.
2. Pass-Through Authentication (PTA)
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Passwords are not stored in Azure.
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Authentication request goes to an on-prem agent for verification.
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Users keep the same password for on-prem and cloud.
Best for: Organizations that require on-premises policies like smartcards or custom logon restrictions.
3. Federation (ADFS)
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Uses Active Directory Federation Services (ADFS).
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Provides single sign-on with advanced policies.
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Authentication happens entirely on-premises.
Best for: Enterprises with complex identity requirements, regulatory needs, or existing ADFS infrastructure.
4. Cloud Sync
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Lightweight sync option using cloud agents.
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Easier to deploy and maintain compared to full Azure AD Connect.
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Still evolving but good for distributed environments.
Confusion Buster
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Azure AD Connect with Password Hash Sync = easiest, most common.
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PTA = passwords validated on-prem, not stored in cloud.
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ADFS = most complex, least common now, but required in some regulated industries.
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Cloud Sync = simplified sync, newer approach.
Example Enterprise Scenario
A global law firm wants:
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Seamless sign-in for Microsoft 365.
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Ability to apply complex login policies (geo-location restrictions).
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Minimal password exposure in the cloud.
Correct design: Federation with ADFS → because they need highly customized login policies.
Exam Tips
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“Which solution syncs passwords into the cloud?” → Azure AD Connect (Password Hash Sync).
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“Which solution verifies passwords on-prem only?” → Pass-Through Authentication.
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“Which is simplest for most organizations?” → Password Hash Sync.
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“Which is required for advanced/custom login rules?” → ADFS.
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“Which lightweight option can replace AD Connect?” → Cloud Sync.
What to Expect in the Exam
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A case study where you must choose the best hybrid identity approach based on business requirements.
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Expect 1–2 scenario-based questions specifically around Azure AD Connect vs PTA vs ADFS.
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Trick questions where two answers look right — always align the choice with the requirement (simplicity, compliance, customization).