In the past, definitely. I'm not sure what the current system is.
Realistically, might as well read https://en.wikipedia.org/wiki/Pager as it knows a lot more than I do. I had a pager for several years and have done network programming, that's about it... i have an insulin pump that people often mistake for a pager though, ha. It makes me look pretty cool.
My guess is Iranian Republicans thought of this scheme. I mean, Iranians have a lot better things to think about right now.