My WiFi is an Android cell phone acting as a hotspot. It's probably offering a lot of protocol options that didn't exist twenty years ago. My laptop connects to it using IPv4. The connection is password protected, and WiFi security has changed a lot over the years.
I'll poke around on the phone and see what configuration options I can control.
Just knowing what the numeric error code means is really helpful. Where would I look to decode that (and others I might encounter)? I'm hardly a Mac expert, I've been running Linux for nearly 30 years now....
Thanks for the quick help!