Public networks vs. Private networks data link

Hello to all;

Analyzing the possible different methods or ways to transmit and receive data for tele-control and tele-supervision of devices, equipment or plant sectors. It is of my interest to know different opinions regarding the advantages and disadvantages of using public networks as GSM, CDMA, 3G, etc. instead of private networks like UHF or VHF spread spectrum. Naturally understanding that both methods are equally possible to use in the same application and place.

I will appreciate any kind of comments.

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