One other level of classification that is missing here is &quot;Free, but requires a local phone number.&quot;<p>Oftentimes, the operator will send you an SMS with a one-time password, but they require a local phone number to send it to.  Or they use your phone number to de-anonymize you, so it must be a phone number from their local country.<p>When traveling, this makes these &quot;open&quot; access points effectively useless, unless you decide to spoof another person&#x27;s MAC address.