Laser Inter-Satellite Links

Laser Mesh Network

Live latency

🟠 Ground fiber (NY→SYD)–

🔵 Space laser mesh–

Fiber distance

–

Laser path distance

–

Satellite hops

–

Laser advantage

–

Constellation size

–

Why space lasers can be faster

Light slows down inside glass fiber to about 0.68c because of the fiber's refractive index (~1.47) — every kilometre of undersea cable costs more time than a kilometre of empty space. A laser inter-satellite link (ISL) crosses true vacuum at the full speed of light, c = 299,792 km/s. Route a data packet through a mesh of low-Earth-orbit (LEO) satellites — hop to hop, as real mega-constellations like Starlink's laser-linked shells already do — and the extra straight-line distance through space can still lose to fiber's slower propagation speed on very long, cable-inefficient routes.

t_fiber = (great_circle_km × cable_detour) / (c × 0.68)
t_laser = Σ hop_km / c + hops × switch_delay

Start data transmission — runs Dijkstra's shortest-path search over the current laser mesh graph (each satellite links to its nearest neighbours) from an uplink near New York to a downlink near Sydney, then animates a packet hop by hop while a second packet races along the undersea fiber route.
Compare: fiber vs laser — toggles the ground-fiber route and its packet off/on, isolating the pure laser-mesh path.
Satellite hops — how many ISL relays the packet used; more hops add small optical switching delays (modelled at ~0.5 ms each) but each hop still crosses vacuum at full c.

Real-world relevance: this is the actual argument satellite-network operators make for laser ISLs on transcontinental and intercontinental routes — not lower bandwidth cost, but genuinely lower physical latency, useful for high-frequency trading, remote surgery telemetry and real-time global backhaul.

Satellite (LEO) Laser ISL mesh Ground fiber route Ground station

⚠ Couldn't load the 3D engineThree.js failed to load from the CDN. Check your connection and reload.