Wi-Fi du train sur Mac : le rendre utilisable, ou passer à votre partage de connexion
Train Wi-Fi usually reaches the internet over mobile networks along the track. All the passengers share that connection, so it is often slow.
Symptômes
- The Mac joins and signs in, but pages load slowly or not at all.
- Calls freeze and uploads stop.
- The connection drops in tunnels and between stations, then comes back.
- The sign-in page appears again after some time.
Causes probables
- A shared connection. The train's connection serves all its passengers. A full train leaves little speed for each device.
- Gaps in mobile coverage. Tunnels, cuttings and rural areas interrupt the mobile networks that the train uses.
- Limits from the operator. Some operators limit the speed, the data or the time for each device. Some block streaming.
- The sign-in, a VPN or custom DNS. Train Wi-Fi often has a sign-in page. A VPN or custom DNS can hide it, as on other public networks.
- Background data on the Mac. Sync, backups and updates use the same small connection as your work.
Comment vérifier
In a browser, open http://captive.apple.com. If the operator's page opens, sign in.
Run Apple's speed test. Write down the result.
networkQualityVoyez quels processus utilisent le réseau en ce moment. Appuyez sur q pour arrêter.
nettop -P -dLook at the mobile signal on your phone. Strong signal and few passengers can make the hotspot faster.
Comment corriger
Turn on Low Data Mode for the train network. Choose Apple menu > System Settings > Wi-Fi.
Click Details next to the train network. Turn on Low data mode. Click OK.
Pause sync, backups and updates until you are on a better network.
In calls, turn off your camera. Audio uses much less of the connection.
If the train Wi-Fi is too slow, click the Wi-Fi icon. Choose your iPhone under Personal Hotspot.
Run the same speed test on the hotspot. Keep the faster of the two.
To stop the Mac from going back to the train Wi-Fi, open its Details. Turn off Automatically join this network.
On the hotspot, pause the apps that use data in the background. See Mac uses Personal Hotspot data in the background.
In tunnels and remote areas, the hotspot can drop too. Save your work before them.
Avec Kilobat
Find which part is slow: Wi-Fi, the router, the internet, DNS or the sign-in page.
kilobat diagnoseCheck the sign-in page, and whether the network logged you out after an earlier sign-in.
kilobat portalTest the speed with a limit on the data that the test uses.
kilobat speedtest --budget-mb 10Voyez l’envoi et la réception en direct de chaque app. Appuyez sur q pour arrêter.
kilobat status --watchMark the train network as metered. Kilobat then treats it like a hotspot.
kilobat networks cost meteredFor travel data packs, see Working from anywhere with a Mac: eSIMs, phone hotspots and making data last.
Questions
Is train Wi-Fi or my hotspot faster?
It depends on the route, the time and your carrier. Test both with the same test, then keep the faster one.
Does train Wi-Fi use my phone's data?
No. Train Wi-Fi does not use your data plan. The Personal Hotspot does.
Is train Wi-Fi safe for work?
Pages with https hide their contents from the network. Turn on a VPN after you sign in, if your work needs one.
Sources
- Apple Developer News : How to modernize your captive network (22 juin 2020)
- Assistance Apple : Réglages Wi-Fi sur Mac
- Assistance Apple : se connecter au partage de connexion d’un iPhone ou iPad
- Assistance Apple : Utiliser Partage de connexion instantané pour vous connecter à votre partage de connexion
- Apple Developer : NWPath isExpensive
- networkQuality(8) and nettop(1), man page installed with macOS 27.2
Vérifié le 29 octobre 2026.