PTI and Authorization
Authorization determines what an authenticated actor may do — read a resource, invoke an API, or act on behalf of a subject. PTI extends authorization into the trust domain: which contexts a producer may emit, which contexts a consumer may lookup, and what subject data crosses tenant boundaries.
1. What authorization is
Authorization systems enforce access control policies after authentication succeeds. Models include:
- RBAC — role-based permissions (admin, analyst, teller)
- ABAC — attribute-based rules (department, clearance, jurisdiction)
- ReBAC — relationship-based access (owner, delegate, guardian)
- OAuth scopes — coarse-grained API permissions on tokens
- Policy engines — OPA, XACML, custom rule evaluation
Authorization answers: Given this authenticated actor, is this action on this resource permitted?
2. What problem authorization solves
| Problem | Authorization response |
|---|---|
| Over-privileged API access | Scope and role restrictions |
| Cross-tenant data leakage | Tenant isolation, row-level security |
| Regulatory purpose limitation | Purpose-bound consent and policy tags |
| Audit accountability | Decision logs, policy version trails |
Authorization protects resources and operations. It does not define how trust signals are structured, scoped to life areas, or exchanged across institutions.
3. What PTI adds
General authorization
- API endpoint permissions
- Resource-level CRUD control
- Application feature flags
PTI adds
- Context entitlements — producers emit only entitled
context_idvalues - Lookup scopes — consumers request only contracted contexts
- Trust envelope disclosure — minimum necessary intelligence export
- Consent gates — cross-context resolution requires subject consent
PTI's Authorization Model is a trust-specific policy layer. Your existing IAM/OAuth scopes govern application access; PTI entitlements govern trust production and consumption.
4. How they compose together
Integration pattern:
- Institution user authenticates and passes application-level authorization (e.g., "loan officer" role).
- Application calls PTI Trust Lookup API with consumer credentials scoped to
lendingandrisk_compliance. - PTI evaluates contract entitlements — rejecting lookup requests for contexts not in the institution's profile.
- Response returns a trust envelope — structured intelligence without raw partner PII beyond contract.
Institution policy engines may further restrict which staff roles see lookup results — PTI does not replace internal HR authorization.
5. When to use each
| Scenario | Application authorization | PTI authorization |
|---|---|---|
| Teller can view customer account | Required | N/A |
| Lender can run trust lookup for lending context | App role check | Required (context entitlement) |
| Partner emits merchant onboarding events | Partner app auth | Required (merchant context entitlement) |
| Cross-context score fusion without consent | Should deny | MUST deny per RFC-007 |
| API gateway rate limiting | Either layer | Either layer |
Use application authorization for UX and internal workflow; use PTI authorization for trust data boundaries.
6. Related PTI spec/RFC links
- Authorization Model
- RFC-002 — Trust Contexts
- RFC-007 — Governance
- RFC-009 — Privacy
- Privacy specification