Connectivity
Starlink on a yacht: one dish, four networks
Starlink has changed life on board: video calls at anchor, streaming for guests, remote support for the engineer. What it has not changed is the oldest rule of yacht IT — a fast connection is only as good as the network behind it. Too often that network is one flat segment in which the owner's laptop, the guests' phones, the crew's tablets and the ship's systems can all see each other.
Leeward Private3 min read
Why one flat network is the real risk
Starlink itself is not the problem. The terminal delivers a connection; what happens behind it is decided by the router and the network design. If every device shares one network, a single compromised guest phone or an infected crew laptop can reach everything else: the owner's devices, cameras, media servers — and in the worst case systems that matter for navigation and safety.
Charter makes this sharper. Every week brings new guests with devices nobody on board has seen before. A network that trusts every device by default trusts strangers.
The four zones every yacht needs
A sound design divides the yacht into zones that cannot reach each other unless a rule explicitly allows it:
- Owner — the family's devices, private files and printers, with the strictest access and guaranteed bandwidth.
- Guests — internet only. Guests reach the web and nothing else on board, and guest devices cannot see each other.
- Crew — a separate network for crew devices, with its own bandwidth limit so that streaming in the crew mess does not slow down the owner's video call.
- Ship systems — bridge, engine monitoring and other operational technology, isolated from all user networks and reachable only through controlled, logged maintenance access.
Technically this means VLANs, separate wireless networks and a firewall between the zones. Where a Starlink router is part of the installation, it can be switched to bypass mode so that a dedicated firewall takes over — the usual setup as soon as a yacht needs more than one network.
Bandwidth: who gets what
Starlink throughput varies with position, weather, network load and the service plan. Without rules, whoever starts the largest download decides how the connection feels for everyone else. Quality-of-service rules fix this: the owner's calls and operational traffic come first, the guest network gets a fair share, and crew streaming gets a defined limit.
Clear limits also keep data costs predictable. A single phone that backs up its entire photo library over the open sea should not be the reason the next invoice surprises anyone.
Failover: Starlink must not be a single point of failure
Starlink is remarkably dependable, but no single link is perfect. Masts and superstructure create obstructions, weather and outages happen, and coverage or permissions differ from one cruising area to the next. A yacht that relies on the internet for operations, security cameras or the owner's business needs a second, independent path — typically 4G/5G with a marine antenna near the coast and VSAT or a second terminal on longer passages.
The decisive part is automation: the firewall detects when the primary path fails and switches over without anyone on board touching a cable. Priorities apply on the backup path too — when bandwidth is scarce, operations and the owner come first.
Remote access and the people behind it
Integrators, AV specialists, the management company, sometimes the yard: many parties need remote access to systems on board. Every one of these accesses is a door. It should be personal rather than shared, protected with multi-factor authentication, logged — and closed when the job is done, not left open for years because nobody remembers it exists.
The same applies to the Starlink account itself. Whoever controls it can change settings, pause the service or move the subscription. It belongs to the owner's organisation, secured with a unique password and multi-factor authentication — not to the personal e-mail address of a former crew member.
A checklist for the next season or refit
- List every device on board and the network it is connected to.
- Separate owner, guests, crew and ship systems into their own zones.
- Place a dedicated firewall behind Starlink and define what may pass between zones.
- Set bandwidth priorities and limits for each zone.
- Add an independent second internet path with automatic failover.
- Review every remote access: personal, multi-factor, logged, time-limited.
- Move the Starlink account to the owner's organisation and secure it.
- Test the setup before the season — including a deliberate failover.
This is what the Leeward Link programme delivers: survey, design, supplier-neutral hardware, installation and handover to the crew — from one source, wherever the yacht is.