Been wanting to integrate SMS authentication for a while... read a lot 
about SMS gateways in linux/rpi, but finding an actual modem that 
supports SMS with US carriers has been the harder part, and really 
didn't want to pay what could be larger fees to Twilio for logins.
So after much consternation, I ordered one of these... hoping that it 
works, will update if it does. Looks like tello has a $5/mo plan w/ no 
data, 100 minutes (won't be using) and free texts.
modem:
https://www.aliexpress.com/item/2251832653392990.html
-- 
Michael J. Ryan - 
tracker1@roughneckbbs.com
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