Natural disaster can kill almost all forms of phone communication.

>Agreed. It's bad enough that you can have local internet failure, but when you talk medical needs you need to look at other possibilities like disaster communications or massive internet outage (cyberwarfare, etc).
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>Phones may still work in these cases (although cyberwarfare has the possibility of taking out phone carriers as well).
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>Aside from courier, radio, or carrier pidgeon, phone/modem is a viable option.