Sure, you can connect the towers to the carrier however you want, and this is why certain carriers can sometimes hack in better quality protocols within-network (see the discussion on voLTE further down the page). Carrier-to-carrier connections, however, still have to use POTS&#x2F;PSTN (since, if you send a voice call to another carrier&#x27;s network, you can&#x27;t <i>a priori</i> know it&#x27;s a smartphone vs. a landline vs. something else right now, and PSTN is the only standard they all agree on). I agree, it&#x27;s dumb.<p>Also see <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Public_switched_telephone_network" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Public_switched_telephone_netw...</a> regarding the 64kbit&#x2F;s limitation.