best response confirmed by ThereseSolimeno (Microsoft)

@ThereseSolimeno @DwightShrute 


'Analog' devices are perhaps poorly named, what they mean is they are not network devices, they don't connect using tcp/ip and you cant plug them into a switch, router or anything else. They need a simple wire connecting them to a phone line.


Some specific sbc provide these analog ports that you can then wire them straight to your device (maybe through a patch panel, but ultimately its one continuous electrical connection.


So yes, if you want to connect analog devices you'll need an sbc on premises you can wire them upto.