Card payments and telemetry need connectivity. The right technology depends on where the machine stands.
Machines most often connect through a cellular modem with a SIM card, less often through the building's Wi-Fi or a network cable. Cellular is independent of the building's infrastructure but needs signal. Wi-Fi and cable need the network administrator's approval and cooperation.
Cellular
The most common in vending. All it needs is signal. In basements and thick-walled halls, an external antenna may be needed.
Wi-Fi and cable
Useful where cellular signal is weak. They require arrangements with the building's IT team, including network security.
Before installing
Check signal at the target spot. The page on places for vending machines (publisher's site) has general placement tips.
FAQ
Does a machine work without internet? Yes, but without online payments and telemetry, unless the system supports offline mode.
Who pays for the SIM card? Usually the machine operator or the telemetry provider.