> Surely a pager message isn't transmitted from every tower everywhere.
They generally are!
Some systems required the sender to select a geographic region to increase bandwidth efficiency, or alternatively the pager owner to update their coarse-scale location with the operator after moving significant distances.
The latter is what the old Iridium satellite pagers did (do?), for example. (Not sure how the new GDB-based ones work.)
> The new Iridium pagers are two-way as far as I've heard.
Apparently that's optional:
> Iridium Burst-enabled devices can be configured as receive-only so that no transmissions are made, a feature valued highly by some customer segments.
(from https://www.iridium.com/services/iridium-burst/)
> I think the service is finally being decommissioned due to the Iridium Next satellites not supporting it anymore.
If that's the case, it would have been inoperable since 2017 – they deorbited the old satellites immediately after confirming deployment of the new ones.
The new Iridium pagers are two-way as far as I've heard. Only the old ones were one-way.
I think the service is finally being decommissioned due to the Iridium Next satellites not supporting it anymore. It has been supported for more than a decade without onboarding new customers though.