I am writing this from a train. If you have ever tried to do real work from one, you know the problem. The connection is not slow so much as unstable, and unstable is worse. It drops, it stalls, it comes back, it drops again. Video calls fall apart and pages hang half-loaded.
There are three reasons train connectivity is so hard, and they stack on top of each other. The train is moving, so it is constantly handing between cell towers and losing line of sight. Hundreds of other passengers are hammering the same onboard Wi-Fi and the same local masts at once. And the mix of networks in range changes every few miles, so whatever was working a minute ago may not be working now. No single link stays good for long.
So I stopped relying on any single link.
The setup
The router is a Peplink MAX BR1 Mini 5G, running firmware 8.6.0. Nothing exotic, it is a palm-sized cellular router. What makes the difference is what I asked it to do: take every usable path at once and combine them.
I connected it to the train Wi-Fi twice, once on the 2.4 GHz band and once on 5 GHz, treating each as a separate WAN. Alongside those I ran a multi-network SIM, so the cellular side was free to attach to whichever mobile network was strongest at any point rather than being locked to one. That gave three live links into the router.
All three were then bonded into a single SpeedFusion tunnel back to a hub. SpeedFusion is Peplink's bonding technology: it breaks your traffic across every available link at the packet level and reassembles it at the far end, so the connection your laptop sees is one steady tunnel rather than three flaky WANs. Firmware 8.6.0 adds SpeedFusion Boost, a built-in optimisation inside that tunnel designed to hold throughput steady across lossy, unpredictable links. Which is exactly what a train gives you.
The numbers
Here is the honest state of those links mid-journey. This is not a demo built to look good; it is what the router was reporting while I worked.
| Link | Latency | Packet loss |
|---|---|---|
| Cellular (multi-network SIM, 5G) | ~1,662 ms | 0.0 |
| Train Wi-Fi, 2.4 GHz | ~105 ms | 0.0 |
| Train Wi-Fi, 5 GHz | ~107 ms | 0.0 |
Look at the cellular line. Latency of roughly 1.6 seconds is dreadful; on its own that link would make interactive work almost impossible. Total throughput across the bond was sitting under 300 kbps. That is not a typo. Half a megabit, give or take, on a good moment.
A 1.6 second latency link and sub-megabit throughput should not be a working connection. Bonded, and held steady, it was.
The number I actually care about is the packet loss column: zero across the bond. That is the whole game. Bonding gave the tunnel more than one path to lean on, and SpeedFusion Boost kept what was left of each path working together instead of falling over. The result was not fast. It was stable. And stable is what lets you work.
Not speed. Persistence.
I did not need much. Claude open in a browser, email, a handful of web pages. None of that is bandwidth-hungry. What it needs is a connection that does not die mid-task. On a train, persistence is the hard part, not speed, and persistence is exactly what a bonded, boosted tunnel is built to deliver.
There is a second shift underneath this, and it is the one worth sitting with. When you work with an AI assistant, a lot of the job becomes setting a task running and letting it work while you do something else. I can hand off a piece of work, put the phone down, and pick up the result later. That changes what "enough connectivity" means. You no longer need a fat, low-latency pipe to get a serious result out of a bad location. You need just enough of a connection to stay in the conversation, and something that keeps that connection alive.
Half a megabit of flaky connectivity, plus an assistant that works asynchronously, is enough to get an enterprise-grade result out of a train seat.
Where this actually matters
A train is a stress test, but the pattern is everywhere. Anywhere the connection is poor, shared, or moving, the same approach applies: take several imperfect links, bond them, and let the tunnel absorb the mess.
- Field engineers and surveyors working from a van or a site with no fixed line.
- Broadcast and live events, where a stable uplink from an awkward location matters more than a fast one.
- Maritime and remote sites juggling cellular and satellite that each drop in and out.
- Pop-up and temporary sites that need to be online on day zero, before any fixed circuit exists.
The kit is not the clever part. The clever part is deciding to stop chasing one good signal and design for the reality that no single link is reliable. Do that, and a train seat becomes a workable office.