Submarine Cable Tools: Calculator, Monitor, Research

Type any two cities, IP addresses, or domain names. GeoCables will find the nearest cable landing points and calculate the actual route.

Press Calculate to get cable distance, estimated latency, and a visual route on the map.

Straight-line is the geometric shortest path. Cable route is the real distance your data travels — cables follow the ocean floor, avoid seismic zones, and stop at intermediate landing points. Always longer.

Round-trip time: how long a packet takes there and back. Light travels through glass fiber at ~200,000 km/s. The initial estimate uses a distance multiplier for the route type. For precise results, click Smart Route — it calculates the actual path through real cables and landing points.

The main feature: builds a full hop-by-hop route using Dijkstra's algorithm over a real graph of 1,900+ landing points, 500+ submarine cables, and overland backbone hubs. Shows each segment — submarine or land — with named cables, distances, and estimated RTT. Always more accurate than the quick estimate above.

London to Tokyo: two real-world paths exist. The overland route runs through Scandinavia, Russia, and China (~10,600 km, ~80ms RTT) — carried by fiber providers like RETN and Cogent. The submarine route goes via the Mediterranean, Suez Canal, Indian Ocean, and Southeast Asia (~26,000 km, ~130ms). Smart Route finds the shortest path and shows you every cable and landing point along the way. Try it: geocables.com/?from=London&to=Tokyo

New York to Sao Paulo: ~7,800 km via the Seabras-1 submarine cable — a direct fiber link from Wall Township, NJ to Praia Grande, Brazil. Straight-line distance: ~7,700 km. Alternative cables: BRUSA, SAm-1, Monet, EllaLink (via Portugal). Smart Route finds the optimal path. Try it: geocables.com/?from=New+York&to=Sao+Paulo

The status bar shows how many cables are actively monitored and when the last measurement was taken. Each cable is checked every 2-3 hours from the nearest probe.

Green = normal, yellow = degraded, red = critical or down, grey = unmonitored. Click any cable to highlight it and see its current RTT, hops, and baseline comparison.

The Alerts tab shows active anomalies and elevated routes. The Checks tab shows all recent measurements — RTT, hop count, ratio vs baseline, and confidence level.

The system compares current RTT against a rolling baseline for each cable. Three levels: Normal (below 2×), Elevated (2×–4×, yellow), and Anomaly (above 4×, red). All status indicators — badge, map, alerts, checks, and email notifications — are driven by a single source: the cable_alerts table.

Enable "Cable anomaly alerts" in your profile settings to receive email notifications when anomalies or elevated routes are detected.

The Event Log at /health/events shows the full chronological history of all detected incidents — spikes, confirmed anomalies, alert escalations, and resolutions. You can get there from the Health Monitor page by clicking "Event Log" in the navigation bar, or from any alert card via the "View full event log" link. The page features: search by cable name or city, filters by event type (spikes, alerts, all) and severity, time range selection (7/30/90 days), and pagination. Events are grouped by incident — related spikes, confirmations, and resolutions for the same cable appear together. The top bar shows real-time counters: Active Now (current open incidents), total Incidents, Spikes, and Resolved in the selected period.

Every 2 hours, GeoCables creates RIPE Atlas ping and traceroute measurements to both ends of each cable from the nearest available probe. Results are collected every 30 minutes, compared against rolling baselines (average of last 20 measurements), and anomalies are detected automatically. Over 1,200 measurements are processed every 48 hours across 695 cable systems.

Layer 1 (Cable level): compares RTT against cable-specific baselines. Ratio >= 4x = Anomaly (red), 2x-4x = Elevated (yellow). A single measurement above 4x immediately flags the cable. Layer 2 (Network level): analyzes hop-by-hop traceroute data across 750+ cities and thousands of IP addresses. Detects degraded links between specific operators — for example, 'Level 3 to Arelion in Sofia: 6x above normal'. Layer 3 (Hop level): tracks individual IP-to-IP links with rolling baselines from 30,000+ link pairs. Detects micro-anomalies invisible at cable level.

Each cable has a dedicated page with technical specs, landing points, length, owners, and current health status from our monitoring system.

Each landing point shows which cables connect there, the city and country, and links to related routes and monitoring data.

Our research section features in-depth analyses of submarine cable routes, anomalies, and infrastructure — written by our engineering team.

Anonymous users can make up to 10 calculations per day. Sign up with your email to get 50 calculations/day, save favorite routes, track calculation history, and receive cable anomaly alerts. Verify your email to unlock API access.

Save frequently used routes by clicking the star icon in calculator results. Access them anytime from your profile.

Generate a personal API key from your profile to integrate GeoCables data into your own applications and monitoring systems.

Toggle "Cable anomaly alerts" in Settings to receive email digests when submarine cable anomalies or elevated latency is detected.

On the Health Dashboard, click the "Network" toggle in the top-left corner of the map. This switches from the submarine cable view to the network intelligence layer showing routing nodes worldwide.

Each dot represents a city where our probes have detected routing nodes. Colors indicate status: green = normal, yellow = elevated or warning, red = critical anomaly (latency spike above baseline), grey = stale (no data for 48+ hours). Critical and warning markers pulse to draw attention.

Curved lines show actual traceroute paths through anomalous cities. Red lines pass through critical nodes, orange through warning nodes. The more severe the anomaly, the more curved the line. Click any city marker to reveal all routes passing through it (highlighted in yellow for 15 seconds).

Click a city marker to see its status, average RTT, number of tracked IPs, total measurement samples, top network (ASN), and a 24-hour RTT sparkline chart. The popup loads detailed data including the top 5 IPs by sample count and all routes passing through that city.

In Network mode, the sidebar displays a ranked list of all anomalous cities with their spike ratio, RTT, IP count, and top network. Click any entry to fly to that city on the map. Cities are sorted by severity — critical first, then warning, then elevated.

A subtle blue heatmap layer shows measurement intensity — areas with more probe traffic glow brighter. This reveals the density of our monitoring coverage across different regions.

When you click a city with elevated or warning status, the popup shows not just general stats but specific degraded links — operator-to-operator connections currently running above normal. For example: 'Level 3 (Sofia) to TATA Communications (Paris): 2.9x +136ms'. This tells you exactly which transit provider is having issues and on which segment. Data comes from real-time analysis of 30,000+ hop-to-hop links with historical baselines.

GeoCables uses RIPE Atlas — a global network of 12,000+ hardware probes hosted by volunteers worldwide. Each probe performs network measurements (ping, traceroute, DNS) on demand. We schedule measurements from probes nearest to cable landing points, ensuring we test the actual submarine segments rather than just terrestrial paths.

The system runs continuously: cable_monitor selects 30 cables per cycle (prioritizing those not checked recently or showing anomalies), creates RIPE Atlas measurements, and logs them. Every 30 minutes, the collector fetches results from the RIPE API, saves RTT and traceroute hops, calculates ratios against baselines, and triggers alerts when thresholds are exceeded. The entire pipeline processes over 600 measurements per day.

Each traceroute reveals the hop-by-hop path your data takes — every router, every city, every network it crosses. GeoCables geolocates each hop IP, identifies the operator (AS number), and tracks RTT differences between consecutive hops. A sudden RTT jump of 150ms between two hops suggests a long submarine cable segment. We use this to detect which specific cable carried the traffic and to identify bottlenecks.

Baselines are not static thresholds — they adapt over time. For each cable route, we maintain a rolling average of the last 20 successful measurements. This means seasonal variations (cable maintenance windows, traffic pattern changes) are absorbed naturally. When current RTT deviates significantly from this adaptive baseline, that is a real signal, not noise.

GeoCables currently monitors 695 submarine cable systems connecting 1,900+ landing points across 150+ countries. The database tracks thousands of unique IP addresses across 750+ cities, with 30,000+ hop-to-hop link pairs analyzed for anomalies. Over 10,000 health checks are generated per week, each including RTT measurements and full traceroute paths.

GeoCables operates measurement probes in 4 locations: Almaty (Kazakhstan), Minsk (Belarus), Tbilisi (Georgia), and Jerusalem (Israel). These are the same servers that run our RIPE Atlas measurements and health checks. With a one-click VPN connection, you route your traffic through any of these probes — and experience the internet as if you were physically in that city.

From the Health Monitor page, click "VPN" on any cable card or use the VPN button in the toolbar. Select a probe location, and the system generates a temporary WireGuard configuration with a QR code. Scan the QR with the WireGuard app on your phone, or download the config file for your desktop. The tunnel activates instantly — no registration required.

We use WireGuard — the fastest and most modern VPN protocol. Unlike OpenVPN or IPSec, WireGuard adds minimal overhead (typically under 5ms latency). The entire protocol is ~4,000 lines of code (vs 100,000+ for OpenVPN), making it simple, auditable, and extremely fast. Keys are generated on-the-fly and are ephemeral — each connection gets a unique cryptographic keypair.

Test cable routes yourself: connect to our Almaty probe and traceroute to Tokyo — you will see the same hops our monitoring system detects. Verify anomalies: if GeoCables shows elevated latency on a cable, connect via VPN and run your own ping tests. Geographic perspective: see how the internet looks from Central Asia, Eastern Europe, the Caucasus, or the Middle East. Each probe sees different routing paths, different transit providers, different submarine cables.

Each VPN key is valid for 24 hours and limited to 10 GB of traffic. One active tunnel per user at a time. Keys are automatically cleaned up after expiration. No logs are kept beyond the technical minimum needed for key management. The VPN is designed for testing and research — not as a permanent proxy service.