Document-Level Access Control Advanced

In enterprise environments, not every user should see every document. RAG access control ensures that retrieval respects existing document permissions, preventing data leakage through AI-generated responses.

Access Control Models

• ACL-based: Each document has an access control list specifying which users or groups can access it. Flexible but complex at scale.
• Role-based (RBAC): Documents are tagged with required roles. Users are assigned roles that determine document visibility.
• Attribute-based (ABAC): Access decisions based on user attributes, document attributes, and environmental conditions. Most flexible, most complex.

Implementation Strategies

• Pre-filtering: Apply access control filters before vector search. Efficient but may reduce retrieval quality if the filtered corpus is too small.
• Post-filtering: Retrieve more results than needed, filter by access rights, return top-k authorized results. Better quality but higher compute cost.
• Hybrid: Pre-filter by broad categories (department, classification level), post-filter by specific user permissions. Balances quality and efficiency.

Integration with Identity Providers

• Sync document permissions from existing systems: SharePoint, Google Drive, Confluence, file servers. Map source permissions to RAG access control.
• Integrate with LDAP/Active Directory for user group membership and role assignments.
• Handle permission changes in near-real-time. When document access is revoked, update the RAG index promptly.

Audit & Verification

• Log every retrieval with: user identity, query, retrieved documents, and access decision for each document.
• Implement periodic access control verification: compare RAG permissions against source system permissions to detect drift.
• Red-team your access control by testing with users who should NOT see certain documents and verifying they cannot retrieve them.