Zanzibar (Google's Authorization System)
Google's global authorization system described in their 2019 paper. Uses relationship tuples and namespace configuration for ReBAC at planetary scale with single-digit millisecond latency.
Zanzibar is Google's global authorization system, described in their 2019 paper "Zanzibar: Google's Consistent, Global Authorization System." It is the canonical implementation of relationship-based access control at planetary scale — serving billions of users with single-digit millisecond latency.
Key concepts from the Zanzibar paper
- Namespaces: typed configuration for objects and relations
- Relationship tuples: (object, relation, subject) — the core data model
- Check API: resolves whether a subject has a relation to an object through graph traversal
- Expand API: reveals why a subject has access — the relationship chain
- Zookies: consistency tokens for staleness-bounded reads
Building vs buying Zanzibar
Implementing Zanzibar is a 6-18 month engineering project requiring distributed systems expertise. Multiple companies have open-sourced their implementations (Ory Keto, SpiceDB). WardenAuth provides managed ReBAC without requiring a dedicated infrastructure team. Read the full comparison.
Related terms
Role-Based Access Control (RBAC) grants permissions via roles. Attribute-Based Access Control (ABAC) evaluates arbitrary attributes (user, resource, environment) against policy rules.
Authorization model based on relationships between subjects and objects (e.g., owner, editor, viewer). Popularized by Google's Zanzibar paper. Access is resolved through graph traversal.