My understanding has been that generally, if the cellular network signal was above a certain threshold, phones won't even attempt to use wifi calling. Some carriers used to let you flip a switch to force the phone to prefer wifi over cellular, but some have removed that. ( Verizon for example. )
In my experience some years ago in a similar environment, that cellular threshold to switch was set so low that it was useless. I could be standing in a spot with barely tickling the bottom bar, and nothing. If I flipped to airplane mode, was able to wifi call instantly. On Fri, Aug 2, 2024 at 11:11 AM <chuckchu...@gmail.com> wrote: > Hey all, > > > > Question if anyone knows about cell phone wi-fi calling in > US. Googling isn’t finding what I’m looking for. We have a corporate site > in US where users have BYOD capability, and use their phones with wi-fi > calling enabled. Site uses a single NAT address (IPv4) for BYOD access. > Recently the site reported wi-fi calling had stopped working for all user > phones, Apple and Android, all about the same time. The guest network did > have some bandwidth limitation applied and they had overuse. That was > since resolved, we upped the bandwidth. But the phones all still avoided > wi-fi calling. It’s a manufacturing site with known cell signal issues, so > most users had no signal via carrier. I did not get a packet capture yet > to see what could be going on, we’re 99% sure we’re not blocking traffic. > I’m wondering if the phones have an algorithm to test wi-fi signal, and > perhaps the carriers will blacklist public IPs with known wi-fi calling > issues to avoid cases where an emergency call can’t be made because of > intermittent bad performance? It seems odd that even when no bandwidth > issues exist, it’s not attempted. > > > > Thoughts? > > > > Thanks, > > > > Chuck Church >
