I currently have a functioning arduino project that now needs to be connected to the internet for monitoring. I was going to use a gsm shield but it appears that 2g is being phased out by at&t in the USA. At&t is the only serviceable network at this location.
In terms of 3g connections I'm considering either a shield or a 3g router.
The current monitor is reading a 4-20ma loop to monitor water flow rate. It then averages and totalizes the flow since last reset. I will also be adding an ultrasonic range finder to report water tank level. The level sensor will be on top of a 25 foot tall tank. I can either wire it directly to the current PLC and use a 3g shield or connect it through wifi using a 3g modem/router.
One requirement is that the tank level can be displayed on our near the current monitor.
Any suggestions would be greatly appreciated.