I've been dabbling with VoIP carriers which offer SMS with relatively mixed results when trying to use VoIP numbers to receive 2FA messages.
My goal was to have a dedicated DID/number which I don't publish publicly that receives SMS messages, such that socially engineering access to my primary mobile phone number won't grant an attacker access to my 2FA SMS.
(And yes, I would rather use TOTP. Sadly, some vendors only offer SMS, and won't SMS to a VoIP number)
How do online services determine if a number is VoIP or a true mobile provider? If I port a Canadian VoIP number to a mobile carrier will I be able to receive such messages or will I permanently limit my options by continuing to use this number?