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The Ships layer provides real-time vessel tracking and maritime domain awareness through AIS (Automatic Identification System) data, monitoring critical chokepoints, detecting anomalous vessel behavior, and streaming position updates over WebSocket connections.

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Chokepoint Monitoring

The system monitors 13 strategic waterways where disruptions could impact global trade, powered by three data sources: IMF PortWatch (weekly vessel transit counts), AISStream (real-time 24h crossing counter), and CorridorRisk (risk intelligence).
ChokepointStrategic Importance
Strait of Hormuz20% of global oil transits; Iran control
Suez CanalEurope-Asia shipping; single point of failure
Strait of MalaccaPrimary Asia-Pacific oil route
Bab el-MandebRed Sea access; Yemen/Houthi activity
Panama CanalAmericas east-west transit
Taiwan StraitSemiconductor supply chain; PLA activity
Cape of Good HopeSuez bypass route for VLCCs
Strait of GibraltarAtlantic-Mediterranean gateway; NATO chokepoint
Bosporus StraitBlack Sea access; includes Dardanelles corridor; Montreux Convention
Korea StraitJapan-Korea trade; busiest East Asia corridor
Dover StraitWorld’s busiest shipping lane
Kerch StraitRussia-controlled; Ukraine grain via Azov restricted
Lombok StraitMalacca bypass for large tankers
Each chokepoint card shows real-time transit counts (tanker vs cargo), week-over-week change, and an expandable 180-day time-series chart rendered with TradingView lightweight-charts.

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Density Analysis

Vessel positions are aggregated into a 2-degree grid to calculate traffic density. Each cell tracks:
  • Current vessel count
  • Historical baseline (30-minute rolling window)
  • Change percentage from baseline
Density changes of +/-30% trigger alerts, indicating potential congestion, diversions, or blockades.

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Dark Ship Detection

The system monitors for AIS gaps, vessels that stop transmitting their position. An AIS gap exceeding 60 minutes in monitored regions may indicate:
  • Sanctions evasion (ship-to-ship transfers)
  • Illegal fishing
  • Military activity
  • Equipment failure
Vessels reappearing after gaps are flagged for the duration of the session.

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WebSocket Architecture

AIS data flows through a WebSocket relay for real-time updates without polling: 
AISStream -> WebSocket Relay -> Browser
              (ws://relay)
The connection automatically reconnects on disconnection with a 30-second backoff. When the Ships layer is disabled, the WebSocket disconnects to conserve resources.

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Railway Relay Architecture

Some APIs block requests from cloud providers (Vercel, AWS, Cloudflare Workers). A Railway relay server provides authenticated access: 
Browser -> Railway Relay -> External APIs
           (Node.js)      (AIS, OpenSky, RSS)
Relay Functions:
EndpointPurposeAuthentication
/ (WebSocket)AIS vessel streamAISStream API key
/openskyMilitary aircraftOAuth2 Bearer token
/rssBlocked RSS feedsNone (user-agent spoofing)
/healthStatus checkNone
Environment Variables (Railway):
  • AISSTREAM_API_KEY - AIS data access
  • OPENSKY_CLIENT_ID - OAuth2 client ID
  • OPENSKY_CLIENT_SECRET - OAuth2 client secret
Why Railway?
  • Residential IP ranges (not blocked like cloud providers)
  • WebSocket support for persistent connections
  • Global edge deployment for low latency
  • Free tier sufficient for moderate traffic
The relay is stateless; it simply authenticates and proxies requests. All caching and processing happens client-side or in Vercel Edge Functions. See also Finance Data - Chokepoints for disruption scoring methodology.