A hotel network, in two minutes

Print this page or keep it open. The app and the laptop tool run these steps in this order, and each step has its own time limit. The whole run is at most two minutes. It reports what it saw and what it could not see; it does not tell you the room is fine.

The order

1. Wi-Fi mode (up to 1 s). It is instant, and it tells you whether the join is open at all.
2. Sign-in page check (up to 5 s). Everything after may be blocked until you sign in, so a sign-in page is looked for first.
3. DNS answers (up to 10 s). It needs the internet, so it runs before the local work: a failed internet must not look like a result about the building.
4. Router admin page (up to 5 s). It is one device, the router.
5. Network cameras (up to 45 s). The long step: the sweep, mDNS, UPnP and the ONVIF probe, with Tuya announcements heard while it runs.
6. Can other guests reach me (no extra time). Worked out from the sweep, no extra time.
7. Smart-home exposure (up to 5 s). Worked out from the sweep plus one UPnP search.
8. ARP spoof signal (up to 20 s). Laptop tool only; it runs alongside the sweep.

Time budgets add up to 91 s; the arp step runs alongside the sweep on a laptop.

What you can do with no app at all

• Look at the Wi-Fi mode. Your phone's Wi-Fi settings show the security type of the network you are on. An open network encrypts nothing at the Wi-Fi level.
• Ask the front desk for the exact network name before you join, and join that one. A network with a similar name can be a copy.
• If a sign-in page appears, check the name with the front desk first and do not type a password you use anywhere else.
• For banking or email, use mobile data rather than the hotel Wi-Fi.
• Use a VPN or Private DNS if you have one; it blunts a network that answers DNS dishonestly.

If it finds a camera-shaped device

Airbnb does not allow cameras inside listings. A device that behaves like a camera is a reason to read the listing and ask the host. The check cannot tell a doorbell from something else, and it never accuses anyone.

What none of this can see

A camera that records to a memory card, one on its own network or on mobile data, and one that talks only to its maker's cloud are invisible to a network check. Read the whole list. More about the network check.