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			- Introduced guild charters for Scanner Deno, PHP, Ruby, Native, WebService, Java, Surface.Env, Surface.FS, Surface.Secrets, Surface.Validation, UI, Zastava Observer, Zastava Webhook, Zastava Core, and Plugin Platform. - Each charter outlines the mission, scope, required reading, and working agreements for the respective guilds. - Created task boards for Surface.Env, Surface.FS, Surface.Secrets, Surface.Validation, and Zastava components to track progress and dependencies. - Ensured all documents emphasize determinism, offline readiness, security, and integration with shared Surface libraries.
		
			
				
	
	
	
		
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Air-Gapped Time Anchors & Staleness Budgets
Audience: AirGap Time/Controller/Policy guilds, DevOps
Purpose: Document how air-gapped installations maintain trusted time anchors, compute staleness windows, and expose drift telemetry.
1. Overview
Air-gapped clusters cannot contact external NTP servers. StellaOps distributes signed time anchor tokens alongside mirror bundles so services can reason about freshness and seal state without external clocks.
Key goals:
- Provide deterministic time anchors signed by the mirror authority.
 - Track drift and staleness budgets for scanner reports, advisories, and runtime evidence.
 - Surface warnings to operators (UI/CLI/Notifier) before anchors expire.
 
2. Components
| Component | Responsibility | 
|---|---|
| AirGap Controller | Stores the active time_anchor token and enforces sealed/unsealed transitions. | 
| AirGap Time service | Parses anchor bundles, validates signatures, records monotonic offsets, and exposes drift metrics. | 
| Scheduler & Policy Engine | Query the time service to gate scheduled runs and evidence evaluation. | 
| UI / Notifier | Display remaining budget and raise alerts when thresholds are crossed. | 
3. Time Anchor Tokens
- Distributed as part of mirror/offline bundles (
airgap/time-anchor.json). - Signed with mirror key; includes issuance time, validity window, and monotonic counter.
 - Validation steps:
- Verify detached signature.
 - Compare bundle counter to previously applied anchors.
 - Persist anchor with checksum for audit.
 
 
4. Staleness Budgets
Each tenant/configuration defines budgets:
- Advisory freshness – maximum age of advisory/VEX data before rescans are required.
 - Scanner evidence – acceptable drift between last scan and current anchor.
 - Runtime posture – tolerated drift before Notifier raises incidents.
 
AirGap Time calculates drift = now(monotonic) - anchor.issued_at and exposes:
/api/v1/time/status– current anchor metadata, drift, remaining budget./api/v1/time/metrics– Prometheus counters (airgap_anchor_drift_seconds,airgap_anchor_expiry_seconds).
5. Operator Workflow
- Import new mirror bundle (includes time anchor).
 - AirGap Time validates and stores the anchor; Controller records audit entry.
 - Services subscribe to change events and recompute drift.
 - UI displays badge (green/amber/red) based on thresholds.
 - Notifier sends alerts when drift exceeds warning or expiry limits.
 
6. Implementation Notes
- Use 
IAirGapTimeStorefor persistence; default implementation relies on Mongo with tenant partitioning. - Ensure deterministic JSON serialization (UTC ISO-8601 timestamps, sorted keys).
 - Test vectors located under 
src/AirGap/StellaOps.AirGap.Time/fixtures/. - For offline testing, simulate monotonic clock via 
ITestClockto avoid system clock drift in CI. 
7. References
docs/airgap/airgap-mode.mdsrc/AirGap/StellaOps.AirGap.Timesrc/AirGap/StellaOps.AirGap.Controllersrc/AirGap/StellaOps.AirGap.Policy